Introduction to Plastics
Chapter 1
Professor Joe Greene
CSU, CHICO
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MFGT 041
August 25, 1999
Chapter 1: Introduction to Plastics
• Objectives
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Definition of Plastics
Uses of Plastics and Composites
History of Plastics
Raw Material Supply and Pricing
Strategic Materials
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Automotive Applications of
Plastics and Composites
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Composite Intensive Vehicles
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Automotive Plastics and Composites Use
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Automotive Plastics and Composites Use
• Exterior
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doors (Saturn, Camaro, Viper, Corvette)
hoods (Viper, Corvette, Ford trucks, Heavy duty trucks)
fenders (Saturn, Corvette, Viper)
bumper covers (all cars have soft fascia)
• Interior
– instrument panels, door trim, seats, consoles
• Engine
– valve covers, intake manifolds, fluid containers, etc.
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Recreational Plastics and Composites Use
• Snow Equipment
– skis, snow boards, snow mobiles, etc.
• Water Sports Equipment
– water skis, water crafts, snorkel equipment, fishing gear
– diving equipment and clothes
– drinking containers
• Land Sports Equipment
– shoes, roller blades, skate boards, tennis, golf, etc.
• Air Sports Equipment
– plane kits, sky diving clothing and equipment
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Medical Plastics and Composites Use
• Containers
– bottles, blister packages
• Medical drug delivery systems
– IV bags, time release coatings for drugs
– tubing and cathoders for surgery
• Medical Equipment
– Clothing, needle containers, etc.
• The use of plastic materials in the medical field is
constantly increasing and is estimate to reach 4
billion dollars by 2000 (only in the US).
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Commercial Plastics Usage
• Packaging
– Wrapping, bags, bottles, blister packages, shrink wrap.
• Textiles
– Clothing, carpets, fabrics, diapers, netting for sports
• Furniture, Appliances, Housewares
– Telephones and other communication equipment,
computer housings and cabinets, luggage, seating,
components for washers, dryers, etc.
– Musical instruments, CDs, VCRs, TVs, cases
• Construction
– Moldings, counter tops, sinks, flooring, cups, paints,8 etc.
Definition of Plastics
• Plastics come from the Greek plastikos, which
means to form or mold.
– Plastics are solids that flow (as liquid, molden, or soften
state) when heat is applied to material.
• Polymers are organic materials that come from
repeating molecules or macromolecules
– Polymer materials are made up of “many” (poly)
repeating “units”(mers).
– Polymers are mostly based in carbon, oxygen, and
hydrogen. Some have Si, F, Cl, S
– Polymers are considered a bowl of spaghetti or a bag of
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worms in constant motion.
Definition of Plastics
All Materials
Simple
Liquids
Gases
Metals
Ceramics
Solids
Polymers
(polymeric molecules)
Thermoplastics
Heat Forming
Thermosets
Heat Setting
Elastomers
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History
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Natural Plastics
Early Modified Natural Materials
Early Synthetic Plastics
Commercial Synthetic Plastics
Petroleum Basis
Chronology of Polymer Science and Technology
World Production and Per Capita Consumption
Growth Comparison, Plastics and Gross National
Product
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Natural Plastics
• Horn
– Applications- Spoons, combs, and lantern windows
– Properties- strong, did not rust, no bad odor or residue, good
impact, some-what ductile
– History
• (2000 B.C.) Pharaohs of Egypt. Craftsmen softened tortoise shells in oil,
pressed into shape, trimmed, sanded, and polished.
• (1700s England) Boil horns in water or alkaline solutions and then pressed.
• (1700s America) Horners made combs and buttons.
– Issues
• Lack of flowability of horn and nonuniformity in size and flexibility.
• Lack of decorative buttons and moldable material
• Strong odor and waste products from horns, hooves, and other horn
materials
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Natural Plastics
• Shellac
– History
• Insect material from small lac bug (Asia and India)
• Female lives off of sap from tree and is covered in sap.
• The harden excretion is Shellac (shell of a lac)
– Applications
• Protective coating for furniture
• Moldable plastic (US in 1852) for cases, buttons, knobs,
electrical insulation, phonograph ecords (till 1930s)
– Issues
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Volume and quality of material
Arduous cleaning process
Moisture absorption
Inconsistent color
Aging
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Natural Plastics
• Gutta percha
– History
• Palaquium gutta trees from the Malay peninsula
• (1843) Gutta percha was used to make knife handles
– Properties
• Softened in hot water and then pressed into desired shape
• Solid at room temperature and is ductile and strong
• At higher temperature it can be drawn out into strips with no recoil like
rubber
• Highly inert and resists vulcaization
– Applications
• Excellent insulator for Transatlantic Cables (Used until the 1930s)
– Issues
• Inconsistent properties and supply volumes
• Contamination
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Early Modified Natural Materials
• Natural Rubber (gum rubber_ natural latex)
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Little industrial significance compared to gutta percha
Melted in hot temperatures and cracked in cold temperatures
Vulcanization of rubber with sulfer (1839) by Goodyear
Small amounts of sulfer = rubber; Large amounts = ebonite (hard)
Civil War required large amounts of rubber
Today- Rubber is a multi Billion $ business
• Celluloid (substitute for horn, ivory, tortoise shell)
– Conversion of cotton into nitrocellulose (sulfuric acid and nitric
acid): highly nitrated is explosive, moderately nitrated is useful
– Pyroxylin is soluble in several solvents, used as a finish.
– Solid Pyroxylin called celluloid (powdered Pyroxylinwith
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pulverized gum camphor) heated and molded for Billiard balls.
Early Synthetic Plastics
• Phenolics (named Bakelite by Leo Bakeland)
– Phenol and formaldehyde reaction after heat
– Resin could be shaped and hardened with heat
– Replacement for celluloid for billiard balls (1909)
• Phenolics used for telephone equipment (1912)
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Phenolics used for automotive electrical (1916)
Used for handles for cooking pans and electrical switches
Excellent thermal and electrical insulator
Coatings for paper and wood (Formica) and adhesive for
particle board.
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– In 1991 US Plastics industry used 165 millions pounds
Commercial Synthetic Plastics
• Several Polymers found by mixing simple gases under
extreme conditions (high heat and pressure)
– Ethylene gas to form polyethylene using addition polymerization.
– Modifications to ethylene gas to form PVC, polystyrene,
polypropylene, and polymethyl methacrylate.
– Nylon discovered by Dr. Carothers (Harvard) and a new method
called condensation polymerization in 1930s with DuPont.
– Polyesters, PBT and PET, produced via condensation.
• Post WWII boom in plastics
– PTFE, synthetic rubber, polyesters, ABS, polycarbonates,
polyurethanes, etc.
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Petroleum Basis
• Plastics are made from small molecules (monomers)
that are usually derived from crude oil.
– Exception is ethylene which about 50% comes from
natural gas and 50% from crude oil
– Exception is some plastics can be derived from coal,
corn, oats, tree sap, fish oil, and other natural oils.
• U.S. Petroleum Consumption in 1998
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62% Transportation
25% Industrial (excluding plastics)
11% Residential and Commercial
2% Plastics
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Growth Comparison, US Plastics
US Plastics Sales Growth
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Metric Tons (K)
• From 1984 to 1994
growth of 5%
annually
• In 1991, Plastics
account for 11% of
all Shipments in US
• In 1991, Plastics.
account for 3% of
US workforce.
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Series1
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0
1980
1985
1990
1995
2000
Year
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Current Status of the Plastics Industry
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Major Plastic Materials
Recycling of Plastics
Disposal by Incineration or Degradation
Organizations in the Plastics Industry
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Major Plastic Materials (1995)
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LDPE ($0.38/lb)
HDPE ($0.29/lb)
PVC ($0.26/lb)
PP ($0.28/lb)
PS ($0.38/lb)
PU ($0.94/lb)
PET ($0.53/lb)
Phenolic ($0.75/lb)
Total
• Nylon ($1.40/lb)
• PTFE ($6.50/lb)
• PEEK ($36.00/lb)
6.4 M metric tons (1000 kg)
5.3 M metric tons
5.1 M metric tons
4.4 M metric tons
2.7 M metric tons
1.7 M metric tons
1.6 M metric tons
1.5 M metric tons
28.6 M metric tons (82% of market)
0.4 M metric tons
<0.1 M metric tons
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<0.05 M metric tons
Price Volume Relationship of Materials
• Figure 1.4
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Recycling of Plastics
• State and Federal Legislation
• PET bottle recycling
• Codes for plastics
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PET
HDPE
Vinyl/PVC
LDPE
PP
PS
Other
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Disposal by Incineration or
Degradation
• Landfill
• Incineration
• Pyrolysis
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Organizations in the Plastics Industry
• SPE: Society of Plastics Engineers, http://www.4spe.org/
• SPI: Society of the Plastics Industry, http://www.socplas.org/
• SAMPE: Society for the Advancement of Material and
Process Engineering, http://www.sampe.org/
• CFA: Composites Fabricators Association,
http://www.cfa-hq.org/
• CFECA: California Film Extruders & Converters
Association, http://www.cfeca.org/
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