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TECHNOLOGICAL UNIVERSITY OF THE PHILIPPINES VISAYAS
Capt. Sabi St., City of Talisay, Negros Occidental
College of Engineering
Office of the Program Coordinator
LEARNING MODULE
ME 324 A: Materials
Engineering for ME
DEPARTMENT: MECHANICAL ENGINEERING
COMPILED BY:
Engr. Sheila May L. Escobar
2020
This module is a property of Technological University of the Philippines Visayas and intended
for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
1
VISION
The Technological University of the Philippines shall be the premier state university
with recognized excellence in engineering and technology at par with leading universities in
the ASEAN region.
MISSION
The University shall provide higher and advanced vocational, technical, industrial,
technological and professional education and training in industries and technology, and in
practical arts leading to certificates, diplomas and degrees.
It shall provide progressive leadership in applied research, developmental studies in
technical, industrial, and technological fields and production using indigenous materials; effect
technology transfer in the countryside; and assist in the development of small-and-medium
scale industries in identified growth center. (Reference: P.D. No. 1518, Section 2)
QUALITY POLICY
The Technological University of the Philippines shall commit to provide quality higher
and advanced technological education; conduct relevant research and extension projects;
continually improve its value to customers through enhancement of personnel competence and
effective quality management system compliant to statutory and regulatory requirements; and
adhere to its core values.
CORE VALUES
T - Transparent and participatory governance
U - Unity in the pursuit of TUP mission, goals, and objectives
P - Professionalism in the discharge of quality service
I - Integrity and commitment to maintain the good name of the University
A - Accountability for individual and organizational quality performance
N - Nationalism through tangible contribution to the rapid economic growth of the
country
S - Shared responsibility, hard work, and resourcefulness in compliance to the mandates
of the university
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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TABLE OF CONTENTS
Page Numbers
TUP Vision, Mission, Quality Policy, and Core Values………………………1
Table of Contents………………………………………………………………..2
Course Description……………………………………………………….3
Learning Outcomes…………………………………………………………
General Guidelines/Class Rules……………………………………………
Grading System……………………………………………………………
Learning Guide (Week No. 1) …………………………………………….
Topic/s………………………………………………………………
Expected Competencies…………………………………………………
Content/Technical Information………………………………………
Progress Check…… ………………………………………………..
References…………………………………………………………
Learning Guide (Week No. 2) ……………………………………………
Topic/s………………………………………………………………
Expected Competencies…………………………………………………
Content/Technical Information ……………………………………
Progress Check…… ………………………………………………..
References…………………………………………………………
Learning Guide (Week No. 3)………………………………………………
Topic/s………………………………………………………………
Expected Competencies……………………………………………………
Content/Technical Information……………………………………
Progress Check…… ………………………………………………..
References…………………………………………………………
Learning Guide (Week No. 4) ……………………………………………
Topic/s………………………………………………………………
Expected Competencies………………………………………………
Content/Technical Information……………………………………
Progress Check…… ………………………………………………..
References…………………………………………………………
List of References………………………………………………
About the Author/s……………………………………………………………..
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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COURSE DESCRIPTION
The course deals with the properties of engineering materials including mechanical, acoustical,
magnetic, chemical, optical and thermal properties; laboratory experiments using equipment include:
tension, compression, bending shear, torsion and impact tests.
LEARNING OUTCOMES
1. Understand the types, nature properties, behavior and characteristics of engineering materials
2. Identify the different and appropriate usage/applications of different materials
3: Perform material testing, compute, analyse and interpret data.
GENERAL GUIDELINES/CLASS RULES
GRADING SYSTEM
The student will be graded according to the following:
Average of examinations
Average of weekly assessment
Midterm Grade
(MTE x .0.30)
End term Grade
(ETE x .0.30)
Final Grade
- 30%
- 70%
: (Average of Weekly Assessments from Week 1 to 6)
X 0.70 +
: (Average of Weekly Assessments from Week 8 to 13) X 0.70 +
: (Midterm Grade + End term Grade) / 2
The passing grade for this course is 5.0.
This module is a property of Technological University of the Philippines Visayas and intended
for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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LEARNING GUIDE
Week No.: __1__
TOPIC/S
Introduction to Materials Science and Engineering and its Applications
Properties and Characteristics of Materials
EXPECTED COMPETENCIES
1: Ability to understand materials engineering, its application and
importance.
2. Ability to identify the different properties and characteristic of
engineering materials.
CONTENT/TECHNICAL INFORMATION
Introduction
From transportation, housing, clothing, communication, recreation, and food
production are that evidences every segment of our everyday lives is influenced to one
degree or another by materials.
Definition
What is Materials Science and Engineering
According to Callister, “materials science” involves investigating the
relationships that exist between the structures and properties of materials. In contrast,
“materials engineering” is, on the basis of these structure–property correlations,
designing or engineering the structure of a material to produce a predetermined set of
properties. From a functional perspective, the role of a materials scientist is to develop
or synthesize new materials, whereas a materials engineer is called upon to create new
products or systems using existing materials, and/or to develop techniques for
processing materials.
“Structure” is at this point a nebulous term that deserves some explanation. In
brief, the structure of a material usually relates to the arrangement of its internal
components. Subatomic structure involves electrons within the individual atoms and
interactions with their nuclei. On an atomic level, structure encompasses the
This module is a property of Technological University of the Philippines Visayas and intended
for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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organization of atoms or molecules relative to one another. The next larger structural
realm, which contains large groups of atoms that are normally agglomerated together,
is termed “microscopic,” meaning that which is subject to direct observation using some
type of microscope. Finally, structural elements that may be viewed with the naked eye
are termed “macroscopic.” The notion of “property” deserves elaboration. While in
service use, all materials are exposed to external stimuli that evoke some type of
response. For example, a specimen subjected to forces will experience deformation, or
a polished metal surface will reflect light. A property is a material trait in terms of the
kind and magnitude of response to a specific imposed stimulus. Generally, definitions
of properties are made independent of material shape and size
Historical Perspective
According to Callister, materials are probably more deep-seated in our culture
more than we know. Historically, the development and advancement of societies have
been intimately tied to the members’ ability to produce and manipulate materials to fill
their needs. In fact, early civilizations have been designated by the level of their
materials development (Stone Age, Bronze Age, Iron Age).1
The earliest humans had access to only a very limited number of materials, those
that occur naturally: stone, wood, clay, skins, and so on.With time they discovered
techniques for producing materials that had properties superior to those
of the natural ones; these new materials included pottery and various metals.
Furthermore,it was discovered that the properties of a material could be altered by
heat treatments and by the addition of other substances. At this point, materials
utilization was totally a selection process that involved deciding from a given, rather
limited set of materials the one best suited for an application by virtue of its
characteristics.
It was not until relatively recent times that scientists came to understand the
relationships between the structural elements of materials and their properties. This
knowledge, acquired over approximately the past 100 years, has empowered them to
fashion, to a large degree, the characteristics of materials. Thus, tens of thousands of
different materials have evolved with rather specialized characteristics that meet the
needs of our modern and complex society; these include metals, plastics,
glasses, and fibers.
The development of many technologies that make our existence so comfortable
has been intimately associated with the accessibility of suitable materials. An
advancement in the understanding of a material type is often the forerunner to the
stepwise progression of a technology. For example, automobiles would not have been
possible without the availability of inexpensive steel or some other comparable
substitute. In our contemporary era, sophisticated electronic devices rely on
components that are made from what are called semiconducting materials.
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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IMPORTANCE ND APPLICATION
:
1. Materials Selection
2. Design
Material Design
Structural design
Technological design
Product Design
.
.
3. Economic Considerations / Cost Benefit Trade Offs
4. Process Improvement
5. Product Development
7. Research
8. Improvement of condition of living
9. Health Care System
10. Communication and Information transmission
11. Consumer Goods
12. Transport
13. Computational Material Science
14. Synthesis and Processing
15. Advancement
Study in materials advances can drive the creation of new products or even new
industries, and could contribute to make incremental improvements and troubleshoot
issues with currently used materials. Industrial applications of materials science
include materials design, cost-benefit tradeoffs in industrial production of materials,
processing methods.
15.1. Smart or intelligent materials form a group of new materials now being
developed that will have a significant influence on many of our technologies.
15.2 Nanotechnology 1) Nano-medicine for disease detection and treatment
15.3 Nano-engineered materials for improved agriculture 3) Nanotechnology
for energy 4) Nano porous materials for water filtration
15.4 Biomaterials science had found vast applications in the fields
of medicine, biology, chemistry, tissue engineering, and materials science. They
are often intended or adapted for medical applications, such as biomedical
devices which perform, augment, or replace a natural function. Biomaterials
are also used every day in dental applications, surgery, and drug delivery.
15.5 Semiconductors, metals, and ceramics are used today to form highly
complex systems, such as integrated electronic circuits, optoelectronic devices,
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and magnetic and optical mass storage media. These materials form the basis of
our modern computing world, and hence, study of materials is of vital
importance.
PROPERTIES OF MATERIALS
A property is a material trait in terms of the kind and magnitude of response to a specific
imposed stimulus. Generally, definitions of properties are made independent of material shape
and size. The properties of engineering materials can be classified into two main groups
(a) physical
(b) Chemical.
Virtually all important properties of solid materials may be grouped into six different
categories:
1) Mechanical properties relate deformation to an applied load or force; examples include:
elastic modulus or Young's modulus and strength; tensile and shear strengths, hardness,
toughness, ductility, deformation and fracture behaviours, fatigue and creep strengths, wear
resistance, etc. The important mechanical properties affecting the selection of a material are:
a) Tensile Strength:
This enables the material to resist the application of a tensile force. To withstand the tensile
force, the internal structure of the material provides the internal resistance.
b) Hardness: It is the degree of resistance to indentation or scratching, abrasion and
wear. Alloying techniques and heat treatment help to achieve the same.
c) Ductility: This is the property of a metal by virtue of which it can be drawn into
wires or elongated before rupture takes place. It depends upon the grain size of the metal
crystals.
d) Impact Strength: It is the energy required per unit crosssectional area to fracture a
specimen, i.e., it is a measure of the response of a material to shock loading.
e) Wear Resistance: The ability of a material to resist friction wear under particular
conditions, i.e. to maintain its physical dimensions when in sliding or rolling contact with a
second member.
f) Corrosion Resistance: Those metals and alloys which can withstand the corrosive
action of a medium, i.e. corrosion processes proceed in them at a relatively low rate are
termed corrosion-resistant.
g) Density: This is an important factor of a material where weight and thus, the mass
is critical, i.e. aircraft components.
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2) Thermal properties of solids can be represented in terms of heat capacity and thermal
conductivity; the characteristics of a material, which are functions of the temperature, are
termed its thermal properties. One can predict the performance of machine components
during normal operation, if he has the knowledge of thermal properties. Specific heat, latent
heat, thermal conductivity, thermal expansion, thermal stresses, thermal fatigue, etc., are few
important thermal properties of materials. These properties play a vital role in selection of
material for engineering applications, e.g. when materials are considered for high temperature
service. Now, we briefly discuss few of these properties:
a)Specific Heat: It is the heat capacity of a unit mass of a homogeneous substance.
For a homogeneous body, c = C/M, where C is the heat capacity and M is the mass of the
body. One can also define it as the quantity of heat required to raise the temperature of a unit
mass of the substance through 1°C. Its units are cal/g/°C.
b)Thermal Conductivity (K): This represents the amount of heat conducted per unit
time through a unit area perpendicular to the direction of heat conduction when the
temperature gradient across the heat conducting element is one unit. Truly speaking the
capability of the material to transmit heat through it is termed as the thermal conductivity.
The higher the value of thermal conductivity, the greater is the rate at which heat will be
transferred through a piece of given size. Copper and aluminum are good conductors of heat
and therefore, extensively used whenever transfer of heat is desired. Bakelite is a poor
conductor of heat and hence used as heat insulator. The heat flow through an area A which is
perpendicular to the direction of flow is directly proportional to the area (A) and thermal
gradient (dt/dx).
c)Thermal Expansion: All solids expand on heating and contract on cooling. Thermal
expansion may take place as linear, circumferential or cubical. A solid which expands equally
in three mutually orthogonal directions is termed as thermally isotropic. The increase in any
linear dimension of a solid, e.g. length, width, height on heating is termed as linear
expansion. The coefficient of linear expansion is the increase in length per unit length per
degree rise in temperature. The increase in volume of a solid on heating is called cubical
expansion. The thermal expansion of solids has its origin in the lattice vibration and lattice
vibrations increases with the rise in temperature. Obviously, the thermal conductivity (K) and
electrical conductivity (σ) vary in the same fashion from one material to another.
d)Thermal Resistance (RT): It is the resistance offered by the conductor when heat
flow due to temperature difference between two points of a conductor. It is given by: where
H _ rate of heat flow and ᶿ1 and ᶿ2 are temperatures at two points (°C).
e)Thermal Diffusivity (h): It is given by: A material having high heat requirement per
unit volume possesses a low thermal diffusivity because, more heat must be added to or
removed from the material for effecting a temperature change.
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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f) Thermal Fatigue: This is the mechanical effect of repeated thermal stresses caused
by repeated heating and cooling. The thermal stresses can be very large, involving
considerable plastic flow. We can see that fatigue failures can occur after relatively few
cycles. The effect of the high part of the temperature cycle on the strength of material plays
an important factor in reducing its life under thermal fatigue.
3) Magnetic properties demonstrate the response of a material to the application of a
magnetic field. Materials in which a state of magnetism can be induced are termed magnetic
materials. There are five classes into which magnetic materials may be grouped:
(i) diamagnetic
(ii) paramagnetic
(iii) ferromagnetic
(iv) antiferromagnetic
(v) ferrimagnetic. Iron, Cobalt, Nickel and some of their alloys and compounds
possess spontaneous magnetisation. Magnetic oxides like ferrites and garnets could be used at
high frequencies.
Due to their excellent magnetic properties along with their high electrical resistivity
these materials today, find use in a variety of applications like magnetic recording tapes,
inductors and transformers, memory elements, microwave devices, bubble domain devices,
recording hard cores, etc. Hysteresis, permeability and coercive forces are some of the
magnetic properties of magnetic substances which are to be considered for the manufacture of
transformers and other electronic components.
4) Electrical Properties- Electrical conductivity, resistivity, dielectric strength, the
stimulus is an electric field are few important electrical properties of a material. A material
which offers little resistance to the passage of an electric current is said to be a good conductor
of electricity. The electrical resistance of a material depends on its dimensions and is given by:
Usually resistivity of a material is quoted in the literature. Unit of resistivity is Ohm-metre. On
the basis of electrical resistivity materials are divided as:
a) Conductors
b) Semiconductors
c) Insulators. In general metals are good conductors. Insulators have very high
resistivity. Ceramic insulators are most common examples and are used on automobile spark
plugs, Bakelite handles for electric iron, plastic coverings on cables in domestic wiring.
5) Optical properties - The optical properties of materials, e.g. refractive index,
reflectivity and absorption coefficient etc. affect the light reflection and transmission the
stimulus is electromagnetic or light radiation.
6) Chemical Properties -These properties includes atomic weight, molecular weight,
atomic number, valency, chemical composition, acidity, alkalinity, etc. These properties
govern the selection of materials particularly in Chemical plant. Deteriorative characteristics
relate to the chemical reactivity of materials. In addition to structure and properties, two other
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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important components are involved in the science and engineering of materials— namely,
―processingǁ ―performance. With regard to the relationships of these four components, the
structure of a material will depend on how it is processed. Furthermore, a material’s
performance will be a function of its properties.
.
PROGRESS CHECK
1. Define Materials science and engineering
2. Differentiate Materials science and materials engineering
3. Give at least 5 importance/application
4. Give at least 10 properties and explain each.
REFERENCES
References:
Text book/s : An Introduction to Materials Science and Engineering 4th Edition by
William D. Callister Jr.
Engineering Materials: Properties and Selection by Kenneth Budinski
LEARNING GUIDE
Week No.: __2__
TOPIC/S
Classification of Materials
Non Metals (Natural Materials)
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EXPECTED COMPETENCIES
1: Ability to classify engineering materials.
2. Ability to understand natural materials, its importance, applications,
properties and characteristics.
3. Ability to identify the different types of natural materials.
4. Ability to explain process flow of any least 10 natural materials.
CONTENT/TECHNICAL INFORMATION
CLASSIFICATION OF ENGINEERING MATERIAL
The traditional method is to classify them according to their nature into
metals, ceramics, polymers and composites. The factors which form the basis of
various systems of classifications of materials in material science and engineering are:
1. The chemical composition of the material,
2. The mode of the occurrence of the material in the nature,
3. The refining and the manufacturing process to which the material is subjected to
prior to acquiring the required properties,
4. The atomic and crystalline structure of material and
5. The industrial and technical use of the material.
Common engineering materials that fall within the scope of material science and
engineering may be classified into one of the following groups:
1. Metals (ferrous and non-ferrous) and alloys
2. Non-Metals (Natural Materials, Natural Gasses,
3.Ceramics
4. Organic Polymers
5. Composites including Wood materials
6. Semi-conductors
7. Biomaterials/Nano Materials
8. Advanced Materials
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Figure 1. classification of engineering materials.
1. METALS
1.1 FERROUS METALS
These are metals and alloys containing a high proportion of the element iron.
They are the strongest materials available and are used for applications where high
strength is required at relatively low cost and where weight is not of primary
importance.
 As an example of ferrous metals such as : bridge building, the structure of large
buildings, railway lines, locomotives and rolling stock and the bodies and highly
stressed engine parts of road vehicles.
 The ferrous metals themselves can also be classified into "families',


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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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Figure 2. Classification of ferrous metals.
1.2 NON – FERROUS METALS



These materials refer to the remaining metals known to mankind. The pure metals
are rarely used as structural materials as they lack mechanical strength.
They are used where their special properties such as corrosion resistance, electrical
conductivity and thermal conductivity are required. Copper and aluminum are used
as electrical conductors and, together with sheet zinc and sheet lead, are use as
roofing materials.
They are mainly used with other metals to improve their strength. Some widely
used non-ferrous metals and alloys are classified as shown in figure 3.
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Figure 3. Classification of non-ferrous metals and alloys.
2. NON – METALLIC MATERIALS
2.1 NON – METALLIC
(SYNTHETIC MATERIALS )
These are non – metallic materials that do not exist in nature, although they are
manufactured from natural substances such as oil, coal and clay. Some typical
examples are classified as shown in figure 4.
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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

They combine good corrosion resistance with ease of manufacture by moulding to
shape and relatively low cost.
Synthetic adhesives are also being used for the joining of metallic components even
in highly stressed applications.
Figure 4. classification of synthetic materials.
2.2 NON – METALLIC
NATURAL MATERIALS
Such materials are so diverse that only a few can be listed here to give a basic introduction to
some typical applications








Wood
Rubber
Glass
Emery
Ceramic
Diamonds
Oils
Silicon
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Figure 5. Classification of natural materials.
COMPOSITE MATERIALS (COMPOSITES)
These are materials made up from, or composed of, a combination of different
materials to take overall advantage of their different properties. In man-made
composites, the advantages of deliberately combining materials in order to obtain
improved or modified properties was understood by ancient civilizations. An example
of this was the reinforcement of air-dried bricks by mixing the clay with straw. This
helped to reduce cracking caused by shrinkage stresses as the clay dried out. In more
recent times, horse hair was used to reinforce the plaster used on the walls and ceiling
of buildings. Again this was to reduce the onset of drying cracks. Nowadays, especially
with the growth of the plastics industry and the development of high-strength fibers, a
vast range combinations of materials is available for use in composites. For example,
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carbon fiber reinforced frames for tennis rackets and shafts for golf clubs have
revolutionized these sports.
CERAMICS
Ceramics are inorganic materials consisting of both metallic and non-metallic elements
bonded together chemically. Ceramics can be crystalline, non-crystalline or a mixture of both.
Generally, they have high melting points and high chemical stabilities. They also have high
hardness and high temperature strength but tend to be brittle. Ceramics are usually poor
electrical conductors.
POLYMERS
Polymers are organic materials which consist of long molecular chains or networks
containing carbon. Most polymers are non-crystalline, but some consist of mixtures of both
crystalline and non-crystalline regions. They typically have low densities and are mechanically
flexible. Their mechanical properties may vary considerably. Most polymers are poor electric
conductors due to the nature of the atomic bonding.
SEMI-CONNDUCTORS
These are the materials which have electrical properties that are intermediate between
the electrical conductors and insulators. The electrical characteristics of semi-conductors are
extremely sensitive to the presence of minute concentrations of impurity atoms; these
concentrations may be controlled over very small spatial regions. Semi-conductors form the
backbone of electronic industry. The semi-conductors have made possible the advent of
integrated circuitry that has totally revolutionized the electronics and computer industries. They
affect all walks of life whether it is communications, computers, biomedical, power, aviation,
defence, entertainment, etc. The field of semi-conductors is rapidly changing and expected to
continue in the next decade. Organic semi-conductors are expected to play prominent role
during this decade. Diamond as semiconductor will also be important. Optoelectronic devices
will provide three dimensional integration of circuits, and optical computing.
Advanced Materials
The materials that are utilised in high-technology (or hightech) applications are sometimes
called advanced materials. By high technology we mean a device or product that operates or
functions using relatively intricate and sophisticated principles; for example, electronic
equipment (VCRs, CD players, etc.), computers, fiber optic systems, spacecraft, aircraft and
military rocketry. These advanced materials are typically either traditional materials whose
properties have been enhanced or newly developed high performance materials. Furthermore,
advanced materials may be of all material types (e.g., metals, ceramics, and polymers) and
are normally relatively expensive. In subsequent chapters are discussed the properties and
applications of a good number of advanced materials—for example, materials that are used
for lasers, ICs, magnetic information storage, liquid crystal displays (LCDs), fiber optics, and
the thermal projection system for the space shuttle orbiter.
4.4 Smart Materials (Materials of the Future)
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Smart or intelligent materials form a group of new materials now being developed
that will have a significant influence on many of our technologies. In addition, the concept of
smart materials is being extended to rather sophisticated systems that consist of both smart
and traditional materials. The field of smart materials attempts to combine the sensor,
actuator and the control circuit on as one integrated unit. Actuators may be called upon to
change shape, position, natural frequency, or mechanical characteristics in response to
changes in temperature, electric fields, and magnetic fields. The combined system of sensor,
actuator and control circuit on as one IC unit, emulates a biological system. These are known
as smart sensors, microsystem technology (MST) or microelectromechanical systems
(MEMS). Materials/devices employed as sensors include optical fibers, piezoelectric
materials, and MEMS. MEMS devices are small in size, light weight, low cost, reliable with
large batch fabrication technology. They generally consist of sensors that gather
environmental information such as pressure, temperature, acceleration etc., integrated
electronics to process the data collected and actuators to influence and control the
environment in the desired manner. The MEMS technology involves a large number of
materials. Silicon forms the backbone of these systems also due to its excellent mechanical
properties as well as mature micro-fabrication technology including lithography, etching, and
bonding. Other materials having piezoelectric, piezoresistive, ferroelectric and other
properties are widely used for sensing and actuating functions in conjunction with silicon.
4.5 Nano-Structured Materials and Nanotechnology
Nanotechnology is a field that deals with control of structures and devices at atomic, molecular and
supermolecular levels as well as the efficient use and manufacture of these devices. Key areas in
Nanotechnology are: 1) Nano-medicine for disease detection and treatment 2) Nano-engineered
materials for improved agriculture 3) Nanotechnology for energy 4) Nano porous materials for water
filtration
NATURAL MATERIALS
NATURAL MATERIALS
Such materials are so diverse that only a few can be listed here to give a basic introduction to
some typical applications

Wood: This is naturally occurring fibrous composite material used for the manufacture
of casting patterns.
Rubber
This is used for hydraulic and compressed air hoses and oil seals. Naturally
occurring latex is too soft for most engineering uses but it is used widely for vehicle
tyres when it is compounded with carbon black.

Glass

This is a hardwearing, abrasion-resistant material with excellent weathering
properties. It is used for electrical insulators, laboratory equipment, optical components
in measuring instruments etaand, in the form of fibers, is used to reinforce plastics. It
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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is made by melting together the naturally occurring materials : silica (sand), limestone
(calcium carbonate ) and soda (sodium carbonate).

Emery
This is a widely used abrasive and is a naturally occurring aluminum oxide.
Nowadays it is produced synthetically to maintain uniform quality and performance.

Ceramic
These are produced by baking naturally occurring clays at high temperatures
after moulding to shape. They are used for high – voltage insulators and high –
temperature – resistant cutting tool tips.

Diamonds
These can be used for cutting tools for operation at high speeds for metal
finishing where surface finish is greater importance. For example, internal combustion
engine pistons and bearings. They are also used for dressing grinding wheels.

Oils
Used as bearing lubricants, cutting fluids and fuels.

Silicon
This is used as an alloying element and also for the manufacture of
semiconductor devices. These and other natural, non-metallic materials can be
classified as shown in figure
PROGRESS CHECK
1. Identify the classification of engineering materials.
2. State at least 5 importance/ applications of natural materials
3. Give at least 10 types of natural materials.
4. Explain process flow of any least 10 natural materials.
REFERENCES
References:
Text book/s
: An Introduction to Materials Science and Engineering 4th Edition by
William D. Callister Jr.
Engineering Materials: Properties and Selection by Kenneth Budinski
Engineering Materials by Msc. Shaymaa Mahmood
This module is a property of Technological University of the Philippines Visayas and intended
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Paper ID: ART20171428 435 International Journal of Science and Research
(IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2015): 78.96 | Impact
Factor (2015): 6.391 Volume 6 Issue 3, March 2017 www.ijsr.net Licensed Under
Creative Commons Attribution CC BY
LEARNING GUIDE
Week No.: __3__
TOPIC/S
Natural Gasses
EXPECTED COMPETENCIES
1: Ability to define natural gasses and identify its importance and
applications,
2. Ability to identify the different types of natural gas and natural gas
deposits.
3. Ability to explain how natural gas is formed.
CONTENT/TECHNICAL INFORMATION
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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What Is Natural Gas?
Natural gas is a mixture of gases which are rich in hydrocarbons. All these gases (methane,
nitrogen, carbon dioxide etc) are naturally found in atmosphere.Natural gas is the earth's
cleanest fossil fuel and is colorless and odorless in its natural state. It is composed of four
hydrocarbon atoms and one carbon atom (CH4 or methane).
Origins
Natural gas reserves are deep inside the earth near other solid & liquid hydrocarbons beds
like coal and crude oil.
Much of the natural gas we find and use today began as microscopic plants and animals
living in shallow marine environments millions of years ago. As living organisms, they
absorbed energy from the sun, which was stored as carbon molecules in their bodies. When
they died, they sank to the bottom of the sea and were covered by layer after layer of
sediment. As this organic feedstock became buried deeper in the earth, heat, combined with
the pressure of compaction, converted some of the biomaterial into natural gas.
Migration
Once natural gas has been generated in nature, it tends to migrate within the sediments and
rocks in which it was created, using the pore space, fractures and fissures that occur naturally
in the subsurface. Some natural gas actually makes it to the surface and shows up in seeps,
while other gas molecules travel until they are trapped or impeded by impermeable layers of
rock, shale, salt or clay. These trapped deposits are the reservoirs where we find natural gas
today.
The Earth's Cleanest Fossil Fuel
Natural gas is composed of four hydrogen atoms and one carbon atom (CH4 or methane).
Colorless and odorless in its natural state, natural gas is the cleanest burning fossil fuel. When
it burns, natural gas produces mostly carbon dioxide, water vapor and small amounts of
nitrogen oxides.
History of Many Uses
The first use of gas energy in the United States occurred in 1816, when gaslights illuminated
the streets of Baltimore, Md. By 1900, natural gas had been discovered in 17 states. During
the years following World War II, expansion of the extensive interstate pipeline network
occurred, bringing natural gas service to customers all over the country.
Today, natural gas is used extensively in residential,
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Home heating through natural gas furnaces
Warming water in hot water heaters
Cooking food on barbecues and gas-burning stoves
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Commercial and industrial applications.
Increasingly, natural gas is being used for electric power generation as well.
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petroleum refining,
food processing,
metal, plastic and
glass industries, and the
pulp and paper industry
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Operating gas fired fireplaces
It is used as fuel for boilers and air conditioners worldwide.
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Natural gas in compressed form is used as fuel for vehicles which is known as CNG.
This is used for making fertilizers also, mainly ammonia.
Almost every building (ranging from corporate offices to restaurants and even pools)
in developed cities utilized natural gas during construction and rely on it for utility
heating
A growing use for natural gas is the natural gas vehicle (NGV), which has
lower emissions than diesel engines or gasoline engines.
As the demand for natural gas rises around the world, so does the need to transport it overseas.
One method of transporting natural gas is in it's liquefied form, or LNG, and this is done using
large ships.
What is Natural Gas used for?
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Natural Gas was used mainly for street and household lighting in the 19th and
20th century.
Now, it has a lot more uses in the homes and industrial applications.
It is used to turn turbines for wind and solar energy generation.
This fossil fuel is used for the production of ammonia which itself is used for making
fertilizers.
It is a domestic fuel as well. It fires stoves in our houses and also runs heaters, ovens,
boilers, etc.
Compressed Natural Gas or CNG, that is gas stored at high pressure, is also used in
some households for heating and cooking purposes.
CNG is also a cheap and environment friendly alternative for a transportation fuel
used in low load vehicles requiring high fuel efficiency.
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Liquefied Natural Gas or LNG is used to power vehicles such as off-road trucks and
trains.
What are the advantages of Natural Gas?
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Natural Gas is a cleaner fuel. It is less harmful to the environment than coal, petrol or
diesel as it has less carbon dioxide emissions.
It can be easily stored and transferred through pipelines.
It is relatively more abundant than other fossil fuels i.e. coal and petroleum.
It is also a safer fuel, as it is lighter than air and dissipates rather than exploding.
It provides instant energy, which is why it is used in oven cooking, as it does not
require pre-heating.
Natural gas can be contained in a variety of different types of deposits that must be accessed
if the natural gas is to be used. While a little over 15% of that natural gas has been recovered,
the rest is contained in four types of deposits: conventional, and the so called unconventional
deposits: Shale gas deposit, Tight gas deposit, and coal bed methane.
Natural gas has been extracted from conventional natural gas deposits for a long time, the
unconventional resources are resources that are being extracted using substantially new
techniques. Please see conventional vs unconventional resources.
Conventional natural gas deposits
Conventional resources are "pockets" of gas contained within relatively porous rock, and they
are the most easily mined. While hydraulic fracturing has allowed for more expansive access
to these deposits, they can be mined without its use.
Coal bed methane
Coal bed methane is natural gas consisting mostly of methane, which is trapped inside coal
seams. This is extracted while the coal is being mined, as diminishing the pressure in the coal
seam allows the gas to flow out of the seam and into a wellbore, where it is extracted.[1]
Shale gas
Shale gas is natural gas found inside a fine-grained sedimentary rock called shale. Shale is
porous (there are lots of tiny spaces inside it), but it is non-permeable, which means the gas
cannot flow through it. Shale gas requires the use of hydraulic fracturing for extraction.
Tight gas
Tight gas is similar to shale gas in that it is trapped inside a porous, non-permeable reservoir
rock. The only differentiation between the two is that the term tight gas includes natural gas
trapped inside reservoir rocks that are not shale.
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TYPES OF NATURAL GASS ENERGY
Methane
Natural gas is stripped down to methane before being used by consumers. It is the most
abundant component of pure natural gas, is highly combustible and can be used for a wide
range of energy purposes. Before methane can be burned, it first has to be stripped from the
natural gas that’s found in oil wells, gas wells and condensate wells. Once processed from
the natural gas, it is used for generating electricity through gas and steam turbines. It is also
sent to homes through pipelines where it’s used for cooking, heating, air conditioning and
other important home activities.
Ethane
Ethane is the next most abundant component of energy found in natural gas. It is a
hydrocarbon and a byproduct of petroleum refining. With a higher heating value than
methane, it is used in several ways after being isolated from natural gas. Once separated
from natural gas, ethane is often used to produce ethylene and polyethylene products. In
turn those are used to produce packaging, trash liners, insulation, wire and other consumer
products.
Propane
Propane is an abundant energy source found in natural gas and is processed in gas or liquid
form. Often found in pipeline gas, propane can be used for a variety of purposes.
Frequently, it is used for fueling engines, cooking with stoves and for central heating within
the home or larger buildings. Propane is also used for many barbecue grills due to its highenergy output and portability. Some buses and larger vehicles are fueled on propane, and
many homes also use the gas for fueling the furnace, water heaters and other essentials.
Butane
Found in natural gas, butane is not as abundant as other hydrocarbons, but it is still a viable
energy source and can be used for a variety of purposes. Isolated during natural gas
processing, butane makes up around 20 percent of natural gas composition. It is often a
component in automobile gas. Refrigeration units and lighters also use a large amount of
butane as fuel. Aerosol cans use butane as a propellant, but this has been flagged as harmful
to the environment.
Like oil, natural gas is a product of decomposed organic matter, typically from ancient
marine microorganisms, deposited over the past 550 million years.
This organic material mixed with mud, silt, and sand on the sea floor, gradually becoming
buried over time. Sealed off in an oxygen-free environment and exposed to increasing
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amounts of heat and pressure, the organic matter underwent a thermal breakdown process that
converted it into hydrocarbons.
The lightest of these hydrocarbons exist in the gaseous state under normal conditions and are
known collectively as natural gas. In its pure form, natural gas is a colorless, odorless gas
composed primarily of methane. Methane, the simplest and lightest hydrocarbon, is a highly
flammable compound consisting of one carbon atom surrounded by four hydrogen atoms
(chemical formula: CH4).
Natural Gas 101
How Natural Gas Is Formed
Shale Gas and Other Unconventional Sources of Natural Gas
Natural Gas Flaring, Processing, and Transportation
Uses of Natural Gas
Environmental Impacts of Natural Gas
The Future of Natural Gas
Once natural gas forms, its fate depends on two critical characteristics of the surrounding
rock: porosity and permeability. Porosity refers to the amount of empty space contained
within the grains of a rock. Highly porous rocks, such as sandstones, typically have porosities
of 5 percent to 25 percent, giving them large amounts of space to store fluids such as oil,
water, and gas. Permeability is a measure of the degree to which the pore spaces in a rock are
interconnected. A highly permeable rock will permit gas and liquids to flow easily through
the rock, while a low-permeability rock will not allow fluids to pass through.
After natural gas forms, it will tend to rise towards the surface through pore spaces in the
rock because of its low density compared to the surrounding rock. Most of the natural gas
deposits we find today occur where the gas happened to migrate into a highly porous and
permeable rock underneath an impervious cap rock layer, thus becoming trapped before it
could reach the surface and escape into the atmosphere.
Diagram showing where natural gas comes from
There are two general categories of natural gas deposits: conventional and unconventional.
Conventional natural gas deposits are commonly found in association with oil reservoirs,
with the gas either mixed with the oil or buoyantly floating on top, while unconventional
deposits include sources like shale gas, tight gas sandstone, and coalbed methane.
US natural gas resources and reserves
The United States is endowed with substantial natural gas resources, and new discoveries and
advances in drilling techniques have revised estimates of their size sharply upward in the past
few years. In 2009, the U.S. Energy Information Administration (EIA) estimated that the U.S.
possesses 2,203 trillion cubic feet of natural gas that could be recovered using current
technology.
Conventional resources represent 46 percent (1,009 trillion cubic feet) of the total resource
base, while the rest includes unconventional natural gas resources, such as tight gas, shale
gas, and coalbed methane. Of the total U.S. gas resource, 273 trillion cubic feet of gas are
classified as “reserves,” which can be extracted under current economic and operational
conditions [1].
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As of 2012, the largest known gas reserves in the world are found in Russia, which has five
times the reserves of the United States [2]. Iran and Qatar have four and three times as much
gas as the U.S., respectively, and significant reserves are also present in Saudi Arabia,
Turkmenistan, United Arab Emirates, Nigeria, and Venezuela. Total world reserves of natural
gas are estimated at 6,707 trillion cubic feet [3].
Exploration and production of conventional natural gas resources
Potential natural gas deposits can be located with seismic testing methods similar to those
used for petroleum exploration. In such tests, gas prospectors use seismic trucks or more
advanced three-dimensional tools that involve setting off a series of small charges near the
Earth’s surface to generate seismic waves thousands of feet below ground in underlying rock
formations.
By measuring the travel times of these waves through the Earth at acoustic receivers known
as "geophones," geophysicists can construct a picture of the subsurface structure and identify
potential gas deposits. However, to verify whether the rock formation actually contains
economically recoverable quantities of natural gas or other hydrocarbons, an exploratory well
must be drilled.
Once the viability of a site is determined, vertical wells are drilled to penetrate the overlying
impermeable cap rock and reach the reservoir. Natural buoyancy then brings the gas to the
surface, where it can be processed and sent to homes.
Figure 1 : How Natural Gas is form
References:
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.
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[1] Energy Information Administration. 2012. Annual Energy Review. Table 4.1 Technically
Recoverable Crude Oil and Natural Gas Resource Estimates, 2009.
[2, 3] Energy Information Administration. 2012. International Energy Statistics. Proved
Reserves of Natural Gas.
PROGRESS CHECK
1: Define natural gas
2. Give at least 5 applications of natural gas.
2. Enumerate different types of natural gas and natural gas deposits.
3. Explain how natural gas is form.
REFERENCES
References:
Text book/s
: An Introduction to Materials Science and Engineering 4th Edition by
William D. Callister Jr.
Engineering Materials: Properties and Selection by Kenneth Budinski
https://energyeducation.ca/encyclopedia/Natural_gas
1. CAPP 2012 Upstream Dialogue: The Facts on Natural Gas
Authors and Editors
Ellen Lloyd, Kandi Wong, James Jenden, Braden Heffernan, Jordan Hanania, Kailyn
Stenhouse, Jason Donev
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LEARNING GUIDE
Week No.: __4__
TOPIC/S
POLYMERS/PLASTICS
EXPECTED COMPETENCIES
1: Ability to understand polymers/plastics, its importance, applications,
properties and characteristics.
2. Ability to identify the different types of polymer/plastics.
CONTENT/TECHNICAL INFORMATION
INTRODUCTION
Plastics and natural materials such as rubber or cellulose are composed of very large
molecules called polymers. Polymers are constructed from relatively small molecular
fragments known as monomers that are joined together.
Wool, cotton, silk, wood and leather are examples of natural polymers that have been
known and used since ancient times. This group includes biopolymers such as proteins and
carbohydrates that are constituents of all living organisms.
IMPORTANCE AND APPLICATION
Synthetic polymers, which includes the large group known as plastics, came into
prominence in the early twentieth century. Various studies had been conducted to engineer
them to yield a desired set of properties (strength, stiffness, density, heat resistance, electrical
conductivity) has greatly expanded the many roles they play in the modern industrial
economy.
PROPERTIES AND CHARACTERISTICS
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We will examine a flexible, transparent plastic bags: polyethylene. It is also one of the
simplest polymers, consisting of random-length (but generally very long) chains made up of
two-carbon units.
Figure 1 Monomer and Polymer
Lines at the ends of the long structure indicate that the same pattern extends indefinitely.
The more compact notation on the right shows the minimal repeating unit enclosed is used to
determine polymer structures.
POLYMERS AND PURE SUBSTANCE
A "pure substance" has a definite structure, molar mass, and properties. It turns out,
however, that few polymeric substances are uniform in this way. This is especially the case
with synthetic polymers, whose molecular weights cover a range of values, as may the
sequence, orientation, and connectivity of the individual monomers. So most synthetic
polymers are really mixtures rather than pure substances
However Free rotation around C—C bonds allows long polymer molecules to curl up
and and tangle Thus polymers generally form amorphous solids. There are, however, ways in
which certain polymers can be partially oriented.
CLASSIFICATION OF POLYMERS
Polymers can be classified in ways that reflect their chemical makeup, or perhaps more
importantly, their properties and applications. Many of these factors are strongly
interdependent, and most are discussed in much more detail in subsequent sections of this page.
According to Structure
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Nature of the monomeric units
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Average chain length and molecular weight
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Homopolymers (one kind of monomeric unit) or copolymers;
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Chain topology: how the monomeric units are connected
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Presence or absence of cross-branching
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Method of polymerization
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According to Properties
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Density
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Thermal properties — can they soften or melt when heated?
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Degree of crystallinity
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Physical properties such as hardness, strength, machineability.
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Solubility, permeability to gases
According to Classification
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molded and formed objects ("plastics")
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sheets and films
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elastomers (i.e., elastic polymers such as rubber)
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adhesives
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coatings, paints, inks
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fibres and yarns
Physical properties of polymers
The physical properties of a polymer such as its strength and flexibility depend on:
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chain length - in general, the longer the chains the stronger the polymer;
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side groups - polar side groups (including those that lead to hydrogen bonding) give
stronger attraction between polymer chains, making the polymer stronger;
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branching - straight, unbranched chains can pack together more closely than highly
branched chains, giving polymers that have higher density, are more crystalline and
therefore stronger;
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cross-linking - if polymer chains are linked together extensively by covalent bonds, the
polymer is harder and more difficult to melt.
CLASSIFICATIONS OF POLYMER
1. According to Degree of Crystallinity
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The crystalline parts of this polymer are shown as semi straight lines. The wavy
entanglements of polymer molecules tend to produce amorphous solids, but it often happens
that some parts can become sufficiently aligned to produce a region exhibiting crystal-like
order, so it is not uncommon for some polymeric solids to consist of a random mixture of
amorphous and crystalline regions. As might be expected, shorter and less-branched polymer
chains can more easily organize themselves into ordered layers than can long chains.
Hydrogen-bonding between adjacent chains also helps, and is very important in fiber-forming
polymers both synthetic (Nylon 6.6) and natural (cotton cellulose).
Figure 2: Crystalline and Amorphous Regions
2. According to Thermal Properties : Thermoplastics and Thermosets
Pure crystalline solids have definite melting points, but polymers, if they melt at all,
exhibit a more complex behavior. At low temperatures, the tangled polymer chains tend to
behave as rigid glasses. For example, the natural polymer that we call rubber becomes hard
and brittle when cooled to liquid nitrogen temperature.
The melting of a crystalline compound corresponds to a sudden loss of long-range
order; this is the fundamental reason that such solids exhibit definite melting points, and it is
why there is no intermediate form between the liquid and the solid states. In amorphous solids
there is no long-range order, so there is no melting point in the usual sense. Such solids simply
become less and less viscous as the temperature is raised.
PLASTICS
According to plastic book, he word plastic itself comes from the Greek word plasticos,
which means to be able to be shaped or moulded by heat. As we will see, shaping plastics by
using heat is a basic part of nearly all plastics manufacturing processes.
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CATEGORIES OF PLASTICS
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Natural plastics - these are naturally occurring materials that can be said to be
plastics because they can be shaped and moulded by heat. An example of thisis amber,
which is a form of fossilised pine tree resin and is often used in jewellery manufacture.
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Semi synthetic plastics
these are made from naturally occurring materials that have been modified or changed
but mixing other materials with them. An example of this is cellulose acetate, which is
a reaction of cellulose fibre and acetic acid and is used to make cinema film.
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Synthetic plastics
these are materials that are derived from breaking down,or ’cracking’ carbon
based materials, usually crude oil, coal or gas, so that their molecular structure
changes. This is generally done in petrochemical refineries under heat and
pressure, and is the first of the manufacturing processes that is required to
produce most of our present day, commonly occurring plastics. Synthetic and
semi synthetic plastics can be further divided into two other categories. These
two categories are defined by the ways in which different plastics react when
heated.
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Thermoplastics (classification under thermal properties)
these are plastics that can be softened and formed using heat, and when cool,
will take up the shape that they have been formed into. But if heat is reapplied
they will soften again. Examples of thermoplastics are acrylic and styrene,
probably the most common plastics found in school workshops.
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Thermosetting plastics (Classification under thermal properties)
these are plastics that soften when heated, and can be moulded when soft, and
when cool they will set into the moulded shape. But if heat is reapplied they will
not soften again, they are permanently in the shape that they have been moulded
into. Why this happens we will look at later. Examples of thermosetting plastics
are polyester resins used in glass reinforced plastics work, and melamine
formaldehyde used in the manufacture of Formica for kitchen work surfaces.
CLASSIFICATION OF PLASTICS
a. Thermoplastics
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Thermoplastics have definite softening point and is observed when the thermal
kinetic energy becomes high enough to allow internal rotation to occur within the bonds
and to allow the individual molecules to slide independently of their neighbors, thus
rendering them more flexible and deformable. This defines the glass transition
temperature tg .Depending on the degree of crystallinity, there will be a higher
temperature, the melting point tm , at which the crystalline regions come apart and the
material becomes a viscous liquid. Such liquids can easily be injected into molds to
manufacture objects of various shapes, or extruded into sheets or fibers.
b. Thermoset
Generally highly cross-linked and doesn;t melt at all. They are to be made into molded
objects, the polymerization reaction must take place within the molds — a far more
complicated process.
TYPES OF PLASTICS
1. COMMON PLASTICS
This category includes both commodity plastics, or standard plastics, and engineering
plastics.
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Polyamides (PA) or (nylons) – fibers, toothbrush bristles, tubing, fishing line and lowstrength machine parts such as engine parts or gun frames
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Polycarbonate (PC) – compact discs, eyeglasses, riot shields, security windows, traffic
lights and lenses
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Polyester (PES) – fibers and textiles
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Polyethylene (PE) – a wide range of inexpensive uses including supermarket bags and
plastic bottles
o High-density polyethylene (HDPE) – detergent bottles, milk jugs and molded plastic
cases
o Low-density polyethylene (LDPE) – outdoor furniture, siding, floor tiles, shower
curtains and clamshell packaging
o Polyethylene terephthalate (PET) – carbonated drinks bottles, peanut butter jars,
plastic film and microwavable packaging
Polypropylene (PP) – bottle caps, drinking straws, yogurt containers, appliances, car
fenders (bumpers) and plastic pressure pipe systems
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Polystyrene (PS) – foam peanuts, food containers, plastic tableware, disposable cups,
plates, cutlery, compact-disc (CD) and cassette boxes
o High impact polystyrene (HIPS) – refrigerator liners, food packaging and vending
cups
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Polyurethanes (PU) – cushioning foams, thermal insulation foams, surface coatings and
printing rollers: currently the sixth or seventh most commonly-used plastic, for instance
the most commonly used plastic in cars
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Polyvinyl chloride (PVC) – plumbing pipes and guttering, electrical wire/cable
insulation, shower curtains, window frames and flooring
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Polyvinylidene chloride (PVDC) – food packaging, such as: Saran
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Acrylonitrile butadiene styrene (ABS) – electronic equipment cases (e.g. computer
monitors, printers, keyboards) and drainage pipe
o Polycarbonate+Acrylonitrile Butadiene Styrene (PC+ABS) – a blend of PC and ABS
that creates a stronger plastic used in car interior and exterior parts, and mobile phone
bodies
o Polyethylene+Acrylonitrile Butadiene Styrene (PE+ABS) – a slippery blend of PE
and ABS used in low-duty dry bearings
2. SPECIALIST PLASTICS
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Polyepoxide (epoxy) – used as an adhesive, potting agent for electrical components, and
matrix for composite materials with hardeners including amine, amide, and boron
trifluoride
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Polymethyl methacrylate (PMMA) (acrylic) – contact lenses (of the original "hard"
variety), glazing (best known in this form by its various trade names around the world;
e.g. Perspex, Plexiglas, Oroglas), aglets, fluorescent light diffusers, rear light covers for
vehicles. It forms the basis of artistic and commercial acrylic paints when suspended in
water with the use of other agents.
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Polytetrafluoroethylene (PTFE), or Teflon – heat-resistant, low-friction coatings, used in
things like non-stick surfaces for frying pans, plumber's tape and water slides
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Phenolics or phenol formaldehyde (PF) – high modulus, relatively heat resistant, and
excellent fire resistant polymer. Used for insulating parts in electrical fixtures, paper
laminated products (e.g. Formica), thermally insulation foams. It is a thermosetting
plastic, with the familiar trade name Bakelite, that can be molded by heat and pressure
when mixed with a filler-like wood flour or can be cast in its unfilled liquid form or cast
as foam (e.g. Oasis). Problems include the probability of moldings naturally being dark
colors (red, green, brown), and as thermoset it is difficult to recycle.
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Melamine formaldehyde (MF) – one of the aminoplasts, used as a multi-colorable
alternative to phenolics, for instance in moldings (e.g. break-resistance alternatives to
ceramic cups, plates and bowls for children) and the decorated top surface layer of the
paper laminates (e.g. Formica)
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Urea-formaldehyde (UF) – one of the aminoplasts, used as a multi-colorable alternative
to phenolics: used as a wood adhesive (for plywood, chipboard, hardboard) and electrical
switch housings.
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Polyetheretherketone (PEEK) – strong, chemical- and heat-resistant
thermoplastic, biocompatibility allows for use in medical implant applications, aerospace
moldings. One of the most expensive commercial polymers.
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Maleimide/bismaleimide – used in high temperature composite materials
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Polyetherimide (PEI) (Ultem) – a high temperature, chemically stable polymer that does
not crystallize
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Polyimide – a high temperature plastic used in materials such as Kapton tape
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Plastarch material – biodegradable and heat-resistant thermoplastic composed
of modified corn starch
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
Polylactic acid (PLA) – a biodegradable, thermoplastic found converted into a variety of
aliphatic polyesters derived from lactic acid, which in turn can be made by fermentation of
various agricultural products such as cornstarch, once made from dairy products

Furan – resin based on furfuryl alcohol used in foundry sands and biologically derived
composites
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Silicone poly (diketoenamine heat resistant resin used mainly as a sealant but also used for
high temperature cooking utensils and as a base resin for industrial paints

Polysulfone – high temperature melt processable resin used in membranes, filtration media,
water heater dip tubes and other high temperature applications

Polydiketoenamine (PDK) – a new type of plastic that can be dunked in acid and reshaped
endlessly, currently being lab tested.
4 Gallery of common synthetic polymers
Thermoplastics gallery
Note: the left panels below show the polymer name and synonyms, structural formula, glass
transition temperature, melting point/decomposition temperature, and (where applicable)
the resin identification symbol used to facilitate recycling.
Polycarbonate (Lexan®)
Tg = 145°C, Tm = 225°C.
This polymer was discovered
independently in Germany
and the U.S. in 1953. Lexan is
exceptionally hard and strong;
we see it most commonly in
the form of compact disks. It was once
widely used in water bottles, but concerns
about leaching of unreacted monomer
(bisphenol-A, an endocrine disrupter) has
largely suppressed this market.
Thin and very strong films of this material
are made by drawing out the molten
Polyethylene terephthalate (PET, Mylar) polymer in both directions, thus orienting
the molecules into a highly crystalline state
that becomes "locked-in" on cooling. Its
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Tg = 76°C, Tm = 250°C.
Nylon (a polyamide)
Tg = 50°C, Tm = 255°C.
Make your own Nylon at home
Nylon Stocking History (Smithsonian)
many applications include food packaging
(in foil-laminated drink containers and
microwaveable frozen-food containers),
overhead-projector film, weather balloons,
and as aluminum-coated reflective material
in spacecraft and other applications.
Nylon has a fascinating
history, both scientific
and cultural. It was invented
by DuPont chemist Wallace
Carothers (1896-1937). The
common form Nylon 6.6 has
six carbon atoms in both parts
of its chain; there are several
other kinds. Notice that the
two copolymer sub-units are held together
by peptide bonds, the same kinds that join
amino acids into proteins.
Nylon 6.6 has good abrasion resistance and
is self-lubricating, which makes it a good
engineering material. It is also widely used
as a fiber in carpeting, clothing, and tire
cord.
For an interesting account of the
development of Nylon, see Enough for One
Liftetime: Wallace Carothers, Inventor of
Nylon by Ann Gaines (1971)
Polyacrylonitrile (Orlon, Acrilan,
"acrylic" fiber)
Tg = 85°C, Tm = 318°C.
Polyethylene
Tg = –78°C, Tm = 100°C.
Used in the form of fibers in rugs, blankets,
and clothing, especially cashmere-like
sweaters. The fabric is very soft, but tends
to "pill" — i.e., produce fuzz-like blobs.
Owing to its low glass transition
temperature, it requires careful treatment in
cleaning and ironing.
Control of polymerization by means of
catalysts and additives has led to a large
variety of materials based on polyethylene
that exhibit differences in densities, degrees
of chain branching and crystallinity, and
cross-linking. Some major types are low-
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density (LDPE), linear low density
(LLDPE), high-density (HDPE).
LDPE was the first
commercial form (1933)
and is used mostly for
ordinary "plastic bags", but
also for food containers
and in six-pack soda can
rings. Its low density is due
to long-chain branching
that inhibits close packing. LLDPE has less
branching; its greater toughness allows its
use in those annoyingly-thin plastic bags
often found in food markets.
LDPE
HDPE
A "very low density" form (VLDPE) with
extensive short-chain branching is now
used for plastic stretch wrap (replacing the
original component of Saran Wrap) and in
flexible tubing.
HDPE has mostly straight
chains and is therefore
stronger. It is widely used
in milk jugs and similar
containers, garbage
containers, and as an
"engineering plastic" for
machine parts.
Polymethylmethacrylate (Plexiglass,
Lucite, Perspex)
Tg = 114°C, Tm = 130-140°C.
This clear, colorless
polymer is widely used in
place of glass, where its
greater impact resistance,
lighter weight, and
machineability are
advantages. It is normally copolymerized
with other substances to improve its
properties. Aircraft windows, plastic signs,
and lighting panels are very common
applications. Its compatibility with human
tissues has led to various medical
applications, such as replacement lenses for
cataract patients. Wikipedia article
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Polypropylene
Tg = –10°C, Tm = 173°C.
PP
Polypropylene is used
alone or as a
copyolymer, usually with
with ethylene. These
polymers have an
exceptionally wide range
of uses — rope, binder
covers, plastic bottles, staple yarns, nonwoven fabrics, electric kettles. When
uncolored, it is translucent but not
transparent. Its resistance to fatigue makes
it useful for food containers and their lids,
and flip-top lids on bottled products such as
ketchup.
Wikipedia article
polystyrene
Polystyrene is transparent but rather brittle,
and yellows under uv light.
Tg = 95°C, Tm = 240°C.
Widely used for inexpensive
packaging materials and
"take-out trays", foam
"packaging peanuts", CD
cases, foam-walled drink
cups, and other thin-walled and moldable
parts. Wikipedia article
PS
polyvinyl acetate
PVA is too soft and low-melting to be used
by itself; it is commonly employed as a
water-based emulsion in paints, wood glue
and other adhesives.
Tg = 30°C
polyvinyl chloride ("vinyl", "PVC")
Tg = 85°C, Tm = 240°C.
PVC
This is one of the world's
most widely used polymers.
By itself it is quite rigid and
used in construction materials
such as pipes, house siding,
flooring. Addition of
plasticizers make it soft and
flexible for use in upholstery,
electrical insulation, shower curtains and
waterproof fabrics. There is some effort
being made to phase out this polymer
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owing to environmental concerns (see
below).
Synthetic rubbers
Neoprene (polychloroprene)
Tg = –70°C
Polybutadiene Tg < –90°C
Neoprene, invented in 1930, was the first
mass-produced synthetic rubber. It is used
for such things as roofing membranes and
wet suits.
Polybutadiene substitutes a hydrogen for
the chlorine; it is the major component
(usually admixed with other rubbers) of
tires. Synthetic rubbers played a crucial role
in World War II: more
SBS (styrene-butadiene-styrene) rubber is a
block copolymer whose special durability
makes it valued for tire treads.
Polytetrafluroethylene (Teflon, PTFE)
Decomposes above 350°C.
Polyaramid (Kevlar)
Sublimation temperature 450°C.
This highly-crystalline
fluorocarbon is
exceptionally inert to
chemicals and solvents.
Water and oils do not
wet it, which accounts for its use in cooking
ware and other anti-stick applications,
including personal care products. It is also
employed in Gore-Tex fabric for rainwear.
These properties — non-adhesion to other
materials, non-wetability, and very low
coefficient of friction ("slipperyness") —
have their origin in the highly
electronegative nature of fluorine whose
atoms partly shield the carbon chain.
Fluorine's outer electrons are so strongly
attracted to its nucleus that they are less
available to participate in London
(dispersion force) interactions. Wikipedia
has informative pages on fluorocarbons and
on Teflon.
Kevlar is known for its ability to be spun
into fibres that have five times the tensile
strength of steel. It was first used in the
1970s to replace steel tire cords. Bulletproof vests are one of it more colorful uses,
but other applications include boat hulls,
drum heads, sports equipment, and as a
replacement for asbestos in brake pads. It is
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often combined with carbon or glass fibers
in composite materials.
The high tensile strength is due in part to
the extensive hydrogen bonding between
adjacent chains.
Kevlar also has the distinction of having
been invented by a woman
chemist, Stephanie Kwolek.
Thermoset plastics
The thermoplastic materials described above are chains based on relatively simple
monomeric units having varying degrees of polymerization, branching, bending, crosslinking and crystallinity, but with each molecular chain being a discrete unit. In thermosets,
the concept of an individual molecular unit is largely lost; the material becomes more like a
gigantic extended molecule of its own — hence the lack of anything like a glass transition
temperature or a melting point.
These properties have their origins in the nature of the monomers used to produce them. The
most important feature is the presence of multiple reactive sites that are able to form what
amount to cross-links at every center.
The phenolic resins, typified by the reaction of phenol with formaldehyde, illustrate the
multiplicity of linkages that can be built.
Phenolic resins
These are made by condensing one or more types of phenols
(hydroxy-substituted benzene rings) with formaldehyde, as
illustrated above. This was the first commercialized synthetic
molding plastic. It was developed in 1907-1909 by the Belgian
chemist Leo Baekeland, hence the common name bakelite.
The brown material (usually bulked up with wood powder)
was valued for its electrical insulating properties (light
fixtures, outlets and other wiring devices) as well as for
consumer items prior to the mid-century. Since that time, more recently developed
polymers have largely displaced these uses. Phenolics are still extensively used as
adhesives in plywood manufacture, and for making paints and varnishes.
Urea resins
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Condensation of formaldehyde with urea yields lighter-colored and
less expensive materials than phenolics. The major use if ureaformaldehyde resins is in bonding wood particles into particle board.
Other uses are as baked-on enamel coatings for kitchen appliances
and to coat cotton and rayon fibers to impart wrinkle- water-, and stain-resistance to
the finished fabrics.
Melamine resins
Melamine, with even more amino (–NH2) groups than urea,
reacts with formaldehyde to form colorless solids that are
harder then urea resins. They are most widely encountered in
dinner-ware (plastic plates, cups and serving bowls) and in
plastic laminates such as Formica.
Alkyd-polyester resins
An ester is the product of the reaction of an organic
acid with an alcohol, so polyesters result when
multifunctional acids such as phthalic acid react with
polyhydric alcohols such as glycerol. The
term alkyd derives from the two words alcohol
and acid.
Alkyd resins were first made by Berzelius in 1847, and they were first
commercialized as Glyptal (glycerine + phthalic acid) varnishes for the paint industry
in 1902.
The later development of other polyesters greatly expanded their uses into a wide
variety of fibers and molded products, ranging from clothing fabrics and pillow
fillings to glass-reinforced plastics (Fiberglass).
Epoxy resins
This large and industrially-important group of
resins typically starts by condensing bisphenol-A
with epichlorohydrin in the presence of a catalyst.
(The -epi prefix refers to the epoxide group in
which an oxygen atom that bridges two carbons.)
These resins are usually combined with others to
produce the desired properties. Epoxies are
especially valued as glues and adhesives, as their
setting does not depend on evaporation and the
setting time can be varied over a wide range. In the two-part resins commonly sold
for home use, the unpolymerized mixture and the hardener catalyst are packaged
separately for mixing just prior to use. In some formulations the polymerization is
initiated by heat ("heat curing"). Epoxy dental fillings are cured by irradiation with uv
light.
Polyurethanes
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Organic isocyanates R–NCO react with multifunctional alcohols to
form polymeric carbamates, commonly referred to as polyurethanes.
Their major use is in plastic foams for thermal insulation and
upholstery, but a very large number of other applications, including
paints and varnishes and plastic wheels used in fork-lift trucks, shopping carts and
skateboards.
Silicones
Polysiloxanes (–Si–O–Si-) are the most important of the small class inorganic
polymers. The commercial silicone polymers usually contained attached organic side
groups that aid to cross-linking. Silicones can be made in a wide variety of forms;
those having lower molecular weights are liquids, while the more highly polymerized
materials are rubbery solids. These polymers have a similarly wide variety of
applications: lubricants, caulking materials and sealants, medical implants, non-stick
cookware coatings, hair-conditioners and other personal-care products.
5 Some important natural polymers
Polymers derived from plants have been essential components of human existence for
thousands of years. In this survey we will look at only those that have major industrial uses,
so we will not be discussing the very important biopolymers proteins and nucleic acids.
Polysaccharides
Polysaccharides are polymers of sugars; they play essential roles in energy storage,
signalling, and as structural components in all living organisms. The only ones we will be
concerned with here are those composed of glucose, the most important of the sixcarbon hexoses. Glucose serves as the primary fuel of most organisms.
Glucose, however, is highly soluble and cannot be easily stored,
so organisms make polymeric forms of glucose to set aside
as reserve storage, from which glucose molecules can be
withdrawn as needed.
Glycogen
In humans and higher animals, the reserve
storage polymer is glycogen. It consists of
roughly 60,000 glucose units in a highly
branched configuration. Glycogen is made
mostly in the liver under the influence of the
hormone insulin which triggers a process in
which digested glucose is polymerized and
stored mostly in that organ. A few hours after a
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meal, the glucose content of the blood begins to fall, and glycogen begins to be broken down
in order to maintain the body's required glucose level.
Starch
In plants, these glucose-polymer reserves are known as starch. Starch granules are stored in
seeds or tubers to provide glucose for the energy needs of newly-germinated plants, and in
the twigs of deciduous plants to tide them over during the winter when photosynthesis (the
process in which glucose is synthesizd from CO2 and H2O) does not take place. The starches
in food grains such as rice and wheat, and in tubers such as potatoes, are a major nutritional
source for humans.
Plant starches are mixtures of two principal forms, amylose and amylopectin. Amylose is a
largely-unbranched polymer of 500 to 20,000 glucose molecules that curls up into a helical
form that is stabilized by internal hydrogen bonding. Amylopectin is a much larger polymer
having up to two million glucose residues arranged into branches of 20 to 30 units. For more
on these two variants of starch, see here.
Cellulose and its derivatives
Cellulose is the most abundant organic compound on the earth. Extensive hydrogen
bonding between the chains causes native celluose to be abut 70% crystalline. It also raises
the melting point (>280°C) to above its combustion temperature.
The structures of starch and cellulose appear to be very similar; in the latter, every other
glucose molecule is "upside-down". But the consequences of this are far-reaching; starch can
dissolve in water and can be digested by higher animals including humans, whereas cellulose
is insoluble and undigestible. Cellulose serves as the principal structural component of green
plants and (along with lignin) in wood.
Cotton is one of the purest forms of cellulose and has been cultivated
since ancient times. Its ability to absorb water (which increases its
strength) makes cotton fabrics especially useful for clothing in very warm
climates.
Cotton also serves (along with treated wood pulp) as the source the
industrial production of cellulose-derived materials which were the first
"plastic" materials of commercial importance.

Nitrocellulose was developed in the latter part of the 19th Century. It is prepared by
treating cotton with nitric acid, which reacts with the hydroxyl groups in the cellulose
chain. It was first used to make molded objects the first material used for a photograpic
film base by Eastman Kodak. Its extreme flammability posed considerable danger in movie
theatres, and its spontaneous slow decomposition over time had seriously degraded many
early films before they were transferred to more stable media. Nitrocellulose was also used
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as an explosive and propellent, for which applications it is known as guncotton. Under the
name celluloid, it was used to make molded objects such as billiard balls. It still has a
number of commercial applications, mainly in specialty coatings.

Cellulose acetate was developed in the early 1900s and became the first artificial fiber that
was woven into fabrics that became prized for their lustrous appearance and wearing
comfort. Kodak developed it as a "safety film" base in the 1930's to replace nitrocellulose,
but it did not come into wide use for this purpose until 1948. A few years later, is became
the base material for magnetic recording tape.

Viscose is the general term for "regenerated" forms of cellulose
made from solutions of the polymer in certain strong solvents.
When extruded into a thin film it becomes cellophane which has
been used as a food wrapping since 1912 and is the base for
transparent adhesive tapes such as Scotch Tape. Viscose solutions
extruded through a spinneret produce fibers known as
rayon. Rayon (right) was the first "artificial silk" and has been used
for tire cord, apparel, and carpets. It was popular for womens' stockings before Nylon
became available for this purpose.
a name="502">
Rubber
A variety of plants produce a sap consisting of a colloidal dispersion of cispolyisoprene. This milky fluid is especially abundant in the rubber tree
(Hevea), from which it drips when the bark is wounded. After collection,
the latex is coagulated to obtain the solid rubber. Natural rubber is
thermoplastic, with a glass transition temperature of –70°C.
cis-polyisoprene
Raw natural rubber tends to be sticky when warm and brittle when cold, so it was little more
than a novelty material when first introduced to Europe around 1770. It did not become
generally useful until the mid-nineteenth century when Charles Goodyear found that heating
it with sulfur — a process he called vulcanization — could greatly improve its properties.
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Why does a rubber band heat up when it is stretched, and why does it spontaneously snap
back? It all has to do with entropy; see here for a concise explanation.
Vulcanization creates disulfide cross-links that prevent the polyisoprene chains from sliding
over each other. The degree of cross-linking can be controlled to produce a rubber having the
desired elasticity and hardness. More recently, other kinds of chemical treatment (such as
epoxidation) have been developed to produce rubbers for special purposes.
Allergic reactions to some of the proteins and chemical additives in natural rubber are not
uncommon.
Natural rubber continues to have a large market despite the many forms of synthetic rubber
available, including synthetic polyisoprene ("synthetic natural rubber"). A sizeable industry is
devoted to developing combinations of these rubbers and butadiene copolymers to suit
special applications.
The largest single use of rubber is the production of vehicle tires. Tires are highly
engineered products that use different kinds of rubber in different parts. For example, the
outer tread surface of tires intended for winter use may employ a special formulation
designed to improve low-temperature flexibility.
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Of course, tires are made of much more than rubber materials. Especially surprising to many
is the high proportion of carbon black (amorphous carbon soot) in tires. This material serves
as a binding and reinforcing agent, a pigment, and it also improves the thermal conductivity
— important for preventing localized overheating.
DIFFERENT TYPES OF PLASTICS AND THEIR CLASSIFICATION
The Society of the Plastics Industry (SPI) established a classification system in 1988 to allow
consumers and recyclers to identify different types of plastic. Manufacturers place an SPI
code, or number, on each plastic product, usually moulded into the bottom. This guide
provides a basic outline of the different plastic types associated with each code number.
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Polyethylene Terephthalate sometimes absorbs odours and
flavours from foods and drinks that are stored in them. Items
made from this plastic are commonly recycled. PET(E)
plastic is used to make many common household items like
beverage bottles, medicine jars, rope, clothing and carpet
fibre.
High-Density Polyethylene products are very safe and are
not known to transmit any chemicals into foods or drinks.
HDPE products are commonly recycled. Items made from
this plastic include containers for milk, motor oil, shampoos
and conditioners, soap bottles, detergents, and bleaches. It is
NEVER safe to reuse
an HDPE bottle as a food or drink container if it didn’t
originally contain food or drink.
Polyvinyl Chloride is sometimes recycled. PVC is used for
all kinds of pipes and tiles, but is most commonly found in
plumbing pipes. This kind of plastic should not come in
contact with food items as it can be harmful if ingested.
Low-Density Polyethylene is sometimes recycled. It is a
very healthy plastic that tends to be both durable and
flexible. Items such as cling-film, sandwich bags,
squeezable bottles, and plastic grocery bags are made from
LDPE.Polypropylene is occasionally recycled.
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Polypropylene is occasionally recycled. PP is strong and can
usually withstand higher temperatures. It is used to make
lunch boxes, margarine containers, yogurt pots, syrup
bottles, prescription bottles. Plastic bottle caps are often
made from PP.
Polystyrene is commonly recycled, but is difficult to do.
Items such as disposable coffee cups, plastic food boxes,
plastic cutlery and packing foam are made from PS.
Code 7 is used to designate miscellaneous types of plastic
not defined by the other six codes. Polycarbonate and
Polylactide are included in this category. These types of
plastics are difficult to recycle. Polycarbonate (PC) is used
in baby bottles, compact discs, and medical storage
containers.
Table 1 : Different Types of Plastics and their Csssification according ot The Society of
Plastic Industry
PROGRESS CHECK
1: Enumerate properties of polymers and plastics.
2. Identify the different types of polymer/plastics.
REFERENCES
References:
Text book/s
: An Introduction to Materials Science and Engineering 4th Edition by
William D. Callister Jr.
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Engineering Materials: Properties and Selection by Kenneth Budinski
LIST OF REFERENCES
Text book/s
: An Introduction to Materials Science and Engineering 4th Edition by
William D. Callister Jr.
Engineering Materials: Properties and Selection by Kenneth Budinski
Engineering Materials: Properties and Selection by Kenneth Budinski
https://energyeducation.ca/encyclopedia/Natural_gas
CAPP 2012 Upstream Dialogue: The Facts on Natural Gas
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ABOUT THE AUTHOR/S
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for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.