Research Title:
A Proposal to create an Alternative A-Grade Plywood out of recycled High-Density
Polyethylene (rHDPE) Plastic: Basis for Plastic Waste Reduction
Leader:
Rentoza, Mary Angela C. 9-Bohr
Members:
Baleda, Jasmine Paula 9-Cavendish
Fetalvero, Mary Nicole F. 9-Kelvin
Jabat, Jan Christina Olivia O. 9-Cavendish
Macawile, Janine Marie S. 9-Bohr
Torrendon, Kathleen Claire L. 9-Ptolemy
RELATED LITERATURE AND STUDIES
A. Foreign
1. A&C Plastics, Inc. (n.d.). What is High Density Polyethylene Sheet (HDPE Sheet)?..
https://www.acplasticsinc.com/informationcenter/r/what-is-hdpe-sheet
High density polyethylene plastic is most commonly known and referred to
as HDPE sheet plastic. This thermoplastic is made from a string of ethylene
molecules (hence, the poly part of polyethylene), and is known for being both
lightweight and strong. With more and more companies embracing sustainability
initiatives, HDPE sheet popularity has skyrocketed as it can cut down on the
material used to produce and package products due to its weight and strength.
2. AAA Polymer. (n.d.). All About HDPE Recycling: What Is HDPE, Benefits, How to
Recycle & More. https://www.aaapolymer.com/hdpe-recycling/
Recycling your HDPE containers not only keeps non-biodegradable waste out of our landfills, it saves
energy. Lots of energy! As a matter of fact, HDPE recycling can save up to twice as much energy that is
used in the creation of virgin plastics. According to the EPA, recycling 10 plastic bottles saves enough
energy to power a laptop computer for over 24 hours. Can you imagine how much energy your facility
can save by engaging in HDPE recycling? The energy required to create products from recycled plastics
like HDPE is much, much less than the energy required to create products from virgin materials. This
practice also helps mitigate the need for the use of fossil fuels.
3. Plastics Makes it Possible. (2018). High Density Polyethylene (HDPE): So Popular.
https://www.plasticsmakeitpossible.com/about-plastics/types-ofplastics/professor-plastics-high-density-polyethylene-hdpe-so-popular/
Yes, I love polypropylene and polyester and silicones and all sorts of other plastics. But highdensity polyethylene (or HDPE) plastic has been courting my favor recently. Not only is it one
of the most versatile of plastics—used in everything from hard hats to house wraps—it’s also
widely recycled, in both its rigid form (e.g., containers) and flexible form (e.g., bags).
Like many other plastics, HDPE often replaces heavier materials, in part because our society
and many companies are pursuing sustainability goals, such as reducing the amount of
material used in packaging and products. “Lightweight and strong” can translate into “less
impact on the environment.” For example, a recent study of six types of packaging found that
plastics can deliver more food with significantly less waste, energy use, and global warming
potential than alternatives.
4. Scranton Products. (n.d.). How Is HDPE Made?.
https://www.scrantonproducts.com/how-is-hdpe-made/
HDPE is made under controlled conditions by applying intense heat to petroleum. This
process, also known as “cracking,” helps create ethylene gas. During its production, the gas
molecules will attach to form polymers, which then produce polyethylene.
After this process, the polyethylene will have a sludgy appearance, but after it’s put through a
series of molds, it forms into granules. Once the molding process is complete, you’ll have a
strong polymer material that can have a variety of uses and applications in your home or
facility.
5. Instructables. (n.d.). How to Recycle HDPE (milk Bottles and Caps) Into Usable
Sheet Material. https://www.instructables.com/How-to-recycle-HDPE-milkbottles-and-caps-into-u/
Source material can be found in the form of plastic milk bottles (also some bottles from household
cleaning supplies, toiletries). Some bottle caps are also HDPE.Briefly, the process comprises:
Cut the bottles and caps up into small pieces - about 1cm square or smaller is good.
Preheat the sandwich toaster (mine goes to 180 Celsius, which is perfect, as this will melt HDPE to a
sticky, toffee-like consistency without burning or producing any noxious fumes).
Place a reusable nonstick baking sheet on the bottom plate of the toaster, then add a heap of HDPE
fragments. Place another nonstick sheet on top and press the toaster closed.
After a few minutes, the plastic will melt together into a rough sheet - take this out (don't attempt
anything without the gloves), peel off the top layer of nonstick and fold in the edges of the melted
plastic, then replace the nonstick sheet and put it all back in the toaster.Repeat until you have a solid
blob of melted plastic between the two nonstick sheets - then clamp this between two flat boards to
cool.Once cooled, the plastic will be very tough and rigid - and can be cut and shaped with hand tools,
or machined.
6. Trenchlesspedia.
(2017).
High
Density
Polyethylene
(HDPE).
https://www.trenchlesspedia.com/definition/2788/high-density-polyethylenehdpe-pipe
High density polyethylene (HDPE) is an extremely versatile plastic which offers a
wide variety of benefits. It is one of the most commonly used plastics in the
United States, found in everything from milk containers to shopping carts. HDPE
is the material of choice for trenchless construction as It’s resistant to mold,
mildew, rotting and insects which makes it a great material for underground
pipes.
7. Omnexus. (n.d.). Polyethylene (PE) Plastic: Properties, Uses, & Application.
https://omnexus.specialchem.com/selection-guide/polyethylene-plastic
Polyethylene is a lightweight, durable thermoplastic with variable crystalline structure. It is
one of the most widely produced plastics in the world (tens of millions of tons are produced
worldwide each year). Polyethylene is used in applications ranging for films, tubes, plastic
parts, laminates, etc. in several markets (packaging, automotive, electrical, etc.).Polyethylene
is made from the polymerization of ethylene (or ethene) monomer. Polyethylene chemical
formula is (C2H4)n.
8. Seaman, G. (2012, May 2). Plastics by the Numbers. Eartheasy: Guides & Articles.
https://learn.eartheasy.com/articles/plastics-by-the-numbers/
Understanding the seven plastic codes will make it easier to choose plastics
and to know which plastics to recycle. For example, water bottles that
display a three or a five cannot be recycled in most jurisdictions in the US. A
three indicates that the water bottle has been made from polyvinyl chloride,
a five means that it’s been made of polypropylene, two materials that are
not accepted by most public recycling centers.
9. Satapathy, S., Kothapalli, R.V.S. (2018). Mechanical, Dynamic Mechanical and
Thermal Properties of Banana Fiber/Recycled High Density Polyethylene
Biocomposites Filled with Flyash Cenospheres. J Polym Environ 26, 200–213.
https://doi.org/10.1007/s10924-017-0938-0
This study presents the preparation of Natural fiber-reinforced biocomposites
based on Recycled High Density Polyethylene (RHDPE)/Banana Fiber (BF)/Fly ash
Cenospheres (FACS) and aims to increase the economic value of these waste
materials. Maleic anhydride grafted HDPE (MA-g-HDPE) was used as a
compatibilizer to increase the dispersion of fibers into the polymer matrix as well
as to increase the compatibility between the matrix and fillers.
10. Mentzer, A. P. (2018, October 22). What is HDPE Plastic?. Sciencing.
https://sciencing.com/hdpe-plastic-5839257.html
Plastics are a type of resin that can be easily molded and are often
used as a cheap, durable packaging material. There are six major
varieties of plastics commonly in use. Some plastic items are made of
a mixture of different resins. High-density polyethylene, also known
as HDPE, is a strong plastic used to make jugs and bottles for shortterm storage. To determine if a container is made form HDPE, look
for a number 2 inside the three-arrow recycling symbol.
11. Tap Plastics. (n.d.). HDPE Smooth.
https://www.tapplastics.com/product/plastics/cut_to_size_plastic/hdpe_sheets/
529
High-density polyethylene (HDPE) is a versatile thermoplastic that is made
from petroleum. This multipurpose material offers excellent chemical
resistance to suit a wide variety of applications at a competitive price. Our
selection of HDPE sheets includes a wide range of sizes, colors,
thicknesses, and customization options to choose from. Polyethylene
sheets are resistant to impact, moisture, and chemicals, making it ideal for
machined parts, industrial cutting boards, wear strips, tank linings, livestock
containment,
material
handling
systems,
and
Businesses, schools, and other organizations choose
other
applications.
12. BFP: British Plastic Federation. (n.d.). Polyethylene (High Density) HDPE.
https://www.bpf.co.uk/plastipedia/polymers/hdpe.aspx
Polyethylene (Polythene) is one of the world’s most popular plastics. It is an enormously
versatile polymer which is suited to a wide range of applications from heavy-duty damp
proof membranes for new buildings to light, flexible bags and films.
Two major types of PE are in use in the films and flexible packaging sector – LDPE (Low
Density) used generally for trays and heavier duty films such as long-life bags and sacks,
poly tunnels, protective sheeting, food bags etc and HDPE (High Density) which is used
for most thin gauge carrier bags, fresh produce bags and some bottles and caps.
13. Thermo Fisher Scientific. (n.d.). High Density Polyethylene (HDPE) Labware.
https://www.thermofisher.com/ph/en/home/life-science/lab-plasticware-supplies/plasticmaterial-selection/high-density-polyethylene-hdpe-labware.html
To truly understand Low-Density Polyethylene and High-Density Polyethylene, we
have to understand their origins. Both materials derive from polyethylene (PE), which
is the most popular plastic in the world, used in everything from supermarket bags to
bullet-proof vests. PE is a thermoplastic created by polymerising ethylene. This can
be done in different ways that produce LDPE and HDPE. In other words, these
polymers have different properties because of the structure of their molecules.
14. Dynalon Labware. (n.d.). Plastic Properties of High Density Polyethylene (HDPE).
https://www.dynalon.com/PublicStore/pages/HDPE_Properties.aspx
HDPE plastics are built to withstand extreme situations. Their strong and durable
nature does not, however, convert easily into inert biomass through the process
of biodegradation*. These plastics can persist for hundreds of years, sometimes
indefinitely, which contributes to the growing problem of plastic pollution.
Bio-Tec Environmental, LLC offers a low-cost, end-of-life solution to help HDPE
become more biodegradable* once in a biologically-active environment, such as
a landfill. EcoPure® additives can be used in manufacturing a wide variety of
HDPE products.
15. Curbell Plastics. (n.d.). HDPE Plastic Material & Properties.
https://www.curbellplastics.com/Research-Solutions/Materials/HDPE
HDPE is also available in a variety of additional grades for applications including
FDA compliant for cutting boards, UV stabilized and woodgrain textured for outdoor
environments, orthotic and prosthetic for addition support, and antimicrobial for
medical facilities. These materials are easy to fabricate using standard machining
methods and common woodworking tools.
16. Cal Recycle. (n.d.). High Density Polyethylene (HDPE, #2).
https://www.calrecycle.ca.gov/plastics/markets/hdpeprofile
Used in nonstructural applications including rigid plastic packaging containers and a variety
of molded products. Examples include milk jugs, juice bottles, film (trash bags, agricultural
film, T-shirts, bags), trash cans, and toys. (American Plastics Council, adapted from Modern
Plastics Encyclopedia, 1995)
This resin is well suited to packaging products, such as milk, with short shelf lives. Pigmented
HDPE bottles generally have better stress crack and chemical resistance than bottles made
with unpigmented HDPE. These properties are needed for packaging such items as household
chemicals and detergents, which have a longer shelf life. Injection-molded HDPE is resistant
to warpage and distortion. It is used for products such as margarine tubs and yogurt
containers. ("Plastic Packaging Opportunities and Challenges," American Plastics Council,
February 1992).
17. Britannica, T. Editors of Encyclopaedia (2020, June 15). High-density
polyethylene. Encyclopedia Britannica. https://www.britannica.com/science/highdensity-polyethylene
HDPE is manufactured at low temperatures and pressures,
using Ziegler-Natta and metallocene catalysts or activated chromium
oxide (known as a Phillips catalyst). The lack of branches in its
structure allows the polymer chains to pack closely together, resulting
in a dense, highly crystalline material of high strength and moderate
stiffness.
18. Perkins, S. (2014, May 21). Better than plywood. Science news for Students.
https://www.sciencenewsforstudents.org/article/better-plywood
HDPE
(short for high-density polyethylene)A strong, dense plastic made from petroleum. It
is commonly used to make milk jugs as well as bottles for shampoo, hair conditioner and
detergent. Its recycling code number is “2”.
19. James, T. (2019, November 14). Common Uses, Advantages and Disadvantages, and
FAQs about HDPE Plastic Packaging. Parkway Plastic Inc.
https://parkwayjars.com/blog-1/common-uses-advantages-and-disadvantages-and-faqsabout-hdpe-plastic-packaging/
HDPE is recyclable and "great for blow-molding applications, particularly food and beverage
containers because it won't leach into the bottles' contents.
High-density polyethylene or HDPE is a commonly used petroleum thermoplastic and the most used of
the three polyethylenes for a wide range of applications. If you look at this plastic under a microscope,
you would see that it has a linear structure with few branches lending to its optimal strength/density
ratio. As a result of its molecular makeup, this polymer shines brightest in applications where moisture
resistance and cost-effectiveness are needed.
20. Bekhta, P., & Sedliačik, J. (2019). Environmentally-Friendly High-Density PolyethyleneBonded Plywood Panels. Polymers, 11(7), 1166. https://doi.org/10.3390/polym11071166
Thermoplastic films exhibit good potential to be used as adhesives for the production of veneer-based composites.
This work presents the first effort to develop and evaluate composites based on alder veneers and high-density
polyethylene (HDPE) film. The effects of hot-pressing temperature (140, 160, and 180 °C), hot-pressing pressure
(0.8, 1.2, and 1.6 MPa), hot-pressing time (1, 2, 3, and 5 min), and type of adhesives on the physical and mechanical
properties of alder plywood panels were investigated. The effects of these variables on the core-layer temperature
during the hot pressing of multiplywood panels using various adhesives were also studied.
21. PlasticEurope. (n.d.). Pyloeffins. https://www.plasticseurope.org/en/about-plastics/whatare-plastics/large-family/polyolefins
HDPE (high-density polyethylene): HDPE is known for its large strength-to-density ratio.
The density of HDPE can range from 0.93 to 0.97 g/cm3 or 970 kg/m3. Although the density
of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little
branching, giving it stronger intermolecular forces and tensile strength than LDPE. It is also
harder and more opaque and can withstand somewhat higher temperatures (120 °C for
short periods).
22. Family Handyman. (n.d.). Understanding Plywood Grades.
https://www.familyhandyman.com/project/understanding-plywood-grades/
“A” Grade. Sanded smooth, paintable. Though some neatly made manufacturer repairs are
acceptable, you should have little trouble finding A-grades that are free of repairs and knots.
23. Goldsberry, C. (2018, January 14). Scientific tests prove HDPE can be recycled at least 10
times. Plastics Today. https://www.plasticstoday.com/packaging/scientific-tests-provehdpe-can-be-recycled-least-10-times
Considering that PET (#1) and HDPE (#2) comprise 97% of all plastic bottles on the market in North
America and are the easiest materials to recycle, the recycling industry often questions why their rate
of recycling is not higher. According to a report from the Association of Plastic Recyclers (APR) and
American Chemistry Council (ACC) released this past November, the total pounds of plastic bottles
collected decreased by 71 million pounds in 2016 compared with 2015, with decreases for both PET
and HDPE.
24. Bear Board. (n.d.). What is HDPE?. https://bearboardlumber.com/bearboard-plasticadvantage/what-is-hdpe.html
High-density polyethylene (HDPE) is one of the most commonly used plastics in the United States.
Labeled as #2 plastic, it is typically found in milk jugs, plastic bags and refillable plastic bottles. In
addition to plastic lumber and recycled plastic furniture, recycled HDPE is used to manufacture lawn and
garden products, buckets, crates, office products and automobile parts.
25. Impact resistance of high-density polyethylene against falling penetrator with different
potential energy https://www.matecconferences.org/articles/matecconf/pdf/2017/39/matecconf_cscc2017_02050.pdf
Polymers in comparison with small molecules have rare properties that are very often difficult to
predict. For dealing with polymeric materials it is desirable to have some knowledge background of the
physical chemistry of polymers. For the industrial practice it is important to know the properties such as
heat capacity or melt viscosity for establishing polymerization and processing conditions. Polymers are
omnipresent and they are used in a huge number of the applications, from consumer products to hightemperature industrial use to medical devices under a wide-range of conditions. Multilayer films,
nanomaterials, electronic devices and electrooptical are being developed in modern polymer science for
end-use performance evaluation
26. High‐density polyethylene (HDPE)‐degrading potential bacteria from marine ecosystem of
Gulf of Mannar, India CiteSeerX — Preparation and Properties of Recycled HDPE/Clay
Hybrids (psu.edu)
High‐density polyethylene (HDPE) is a polyethylene thermoplastic, prepared by a
catalytic process, containing carbon and hydrogen as backbone elements and has
little branching, giving it stronger intermolecular forces and tensile strength (4550 psi
approx.) greater than low‐density polyethylene (LDPE). Generally, it was believed
that higher the density greater the stability because of shortened bond length and
tight packaging. Physically, HDPE is harder, more opaque and can withstand
somewhat higher temperatures (120°C). HDPE is also used in many products and
packaging such as carry bags, milk jugs, detergent bottles, margarine tubs, garbage
containers and water pipes. Thus, they have wide industrial and day‐to‐day
application. The extensive usage of HDPE poses severe environmental threats to
terrestrial and marine ecosystem, as they are hardly degradable and voluminously
dumped after usage.
27. Biodegradation of HDPE by Aspergillus spp. from marine ecosystem of Gulf of Mannar, India
Biodegradation of HDPE by Aspergillus spp. from marine ecosystem of Gulf of Mannar, India
- PubMed (nih.gov)
High density polyethylene (HDPE) is the most commonly found non-degradable solid waste
among the polyethylene. In this present study, HDPE degrading various fungal strains were
isolated from the polyethylene waste dumped marine coastal area and screened under in vitro
condition. Based on weight loss and FT-IR Spectrophotometric analysis, two fungal strains
designated as VRKPT1 and VRKPT2 were found to be efficient in HDPE degradation. Through the
sequence analysis of ITS region homology, the isolated fungi were identified as Aspergillus
tubingensis VRKPT1 and Aspergillus flavus VRKPT2. The biofilm formation observed under
epifluorescent microscope had shown the viability of fungal strains even after one month of
incubation. The biodegradation of HDPE film nature was further investigated through SEM
analysis. HDPE poses severe environmental threats and hence the ability of fungal isolates was
proved to utilize virgin polyethylene as the carbon source without any pre-treatment and prooxidant additives.
28. Andrady, A. L., & Neal, M. A. (2009). Applications and societal benefits of plastics. Phil.
Trans. R. Soc. B3641977–1984
https://royalsocietypublishing.org/doi/full/10.1098/rstb.2008.0304
This article explains the history, from 1600 BC to 2008, of materials that are today
termed ‘plastics’. It includes production volumes and current consumption patterns of
five main commodity plastics: polypropylene, polyethylene, polyvinyl chloride,
polystyrene and polyethylene terephthalate. The use of additives to modify the
properties of these plastics and any associated safety, in use, issues for the resulting
polymeric materials are described. A comparison is made with the thermal and
barrier properties of other materials to demonstrate the versatility of plastics. Societal
benefits for health, safety, energy saving and material conservation are described,
and the particular advantages of plastics in society are outlined. Concerns relating to
littering and trends in recycling of plastics are also described. Finally, we give
predictions for some of the potential applications of plastic over the next 20 years
29. Mizera, A., Manas, M., Manas, D., & Stoklasek, P. (2018). Impact Resistance Study of HighDensity Polyethylene through Drop-Weight and Tensile Impact Tests.
10.4028/www.scientific.net/MSF.919.246
This study deals with high-density polyethylene (HDPE) which was put to the drop weight
and tensile impact tests. HDPE is a semicrystalline thermoplastic polymer which is used
in common applications such as packaging, consumer goods and car tanks. The
injection moulded HDPE samples were subjected the drop weight impact test at different
potential energies and the results were subsequently evaluated and discussed. The
second test was performed on pendulum test machine where impact resistance in tensile
was studied. It was found out that HDPE is a low-cost material with high-performance
properties in the field of the impact resistance which was evaluated in penetration and
tensile test where the plastic
30. Marine board plastic vs plywood for hulls Marine board plastic vs plywood for hulls Glen-L.com (glen-l.com)
Has anyone tried marine board plastic for hulls instead of marine plywood The material is a high
density polyethylene (HDPE) sheet that is specially formulated to withstand harsh outdoor marine
environments. It is manufactured as a continuous extrusion so delamination cannot occur. It is UV
stabilized to prevent degradation from sunlight and retain its beauty. The material will not splinter,
crack, rot, swell or absorb water, is stain resistant and never needs painting, is machinable with standard
woodworking tools, and easily forms for curves and bends. Since it is extruded it may eliminate the need
to scarf or butt joint. There are several sites that have this material but they don't seem to want to
respond to a individual potential customer.
On one site it claimed that it is cheaper and lighter than marine plywood but when I asked for pricing
and technical comparisons with marine plywood they never responded; I even sent a picture of the boat
I want to build so they could see what it would be used for. Not responding is no different than the
marine plywood suppliers as they don't respond either, other than to say that they don't have 4' x 10
foot lengths (my plans call for some). You would think they would at least quote the 4' x 8 ft pieces.
If the cost of marine board plastic is the same or less than marine plywood I think it would be worth
trying and would certainly increase the value of the boat when trying to sell since buyers of used boats
shy away from plywood even though it is covered with fiberglass.
31. HDPE Sheet HDPE Sheet | High Density Polyethylene | Supply Services
HDPE sheet (High Density Polyethylene) is a thermoplastic that offers great properties such as abrasion
and chemical resistance, high impact strength and a low coefficient of friction. HDPE sheet is also
moisture, stain and odour resistant. It is one of the most versatile and durable plastic products available.
Some grades of HDPE sheet are FDA approved for the food processing industry. It is widely recycled, and
for a standard engineering material it has an amazingly high tensile strength.
These properties make HDPE sheet a durable, lightweight and easily fabricated material. Typically an
extruded sheet product, our range of HDPE sheet is available with either a smooth glossy mirror-like
finish or an embossed textured surface. We can also supply planed, compression moulded sheets.
Take a look now at our online properties chart to compare to other engineering plastic materials
32.Facts and Figures about Materials, Waste and Recycling
https://www.epa.gov/facts-and-figures-about-materials-waste-andrecycling/plastics-material-specific-data
Plastics are a rapidly growing segment of municipal solid waste (MSW). While plastics
are found in all major MSW categories, the containers and packaging category had the
most plastic tonnage at over 14.5 million tons in 2018. This category includes bags,
sacks and wraps; other packaging; polyethylene terephthalate (PET) bottles and jars;
high-density polyethylene (HDPE) natural bottles; and other containers.
Manufacturers also use plastic in durable goods, such as appliances, furniture, casings
of lead-acid batteries and other products. EPA does not include plastics in
transportation products, other than lead-acid batteries, in this analysis.
33. POLYETHYLENE SHEETS https://www.lundellplastics.com/specialty-customplastics/polyethylene-sheets.asp
Products made from high-quality plastic have applications across a variety of industries, thanks
to their durability and ability to withstand repeated use in tough environments. We have a variety
of raw poly sheets available for purchase, from high-density polyethylene (HDPE) sheets to rolls
of high-molecular weight polyethylene (HMWPE). Choose from HDPE or UHMW plastic in full or
partial sheets to meet your specific needs.
From HDPE, or high-density polyethylene (HDPE) sheets, to high-molecular-weight
polyethylene rolls, we have the material and size of plastic you need, including:
•
•
•
•
•
•
•
HDPE Poly Sheeting
UHMW
Acrylic (Clear)
Polycarbonate (Clear)
Corrugated HDPE (Black or White)
Black Repro HDPE Sheeting
HMWPE Roll
34. Plywood Guide: Grades and Uses https://austim.com.au/blog/plywood-guidegrades-and-uses/
Plywood is a thin wooden sheet of material consisting of two or more layers
of timber bonded with heat, pressure, and strong resins with the direction of the grain
alternating to create a robust composite material.
There are several kinds of plywood which have different properties based on their
manufacture and intended application. Here we will outline the defining factors in each
grade, the finish and treatments that determine the different grades.
Cross-lamination of veneer layers restricts the movement across the grain due to moisture
and temperature changes. Most structural plywood has more strength in the direction of the
grain, and its recommended that the face grain of structural plywood should run parallel to
the span.
35. Environmentally-Friendly High-Density Polyethylene-Bonded Plywood Panels
https://www.mdpi.com/2073-4360/11/7/1166
Thermoplastic films exhibit good potential to be used as adhesives for the production of veneer-based
composites. This work presents the first effort to develop and evaluate composites based on alder
veneers and high-density polyethylene (HDPE) film. The effects of hot-pressing temperature (140, 160,
and 180 °C), hot-pressing pressure (0.8, 1.2, and 1.6 MPa), hot-pressing time (1, 2, 3, and 5 min), and
type of adhesives on the physical and mechanical properties of alder plywood panels were investigated.
The effects of these variables on the core-layer temperature during the hot pressing of multiplywood
panels using various adhesives were also studied. Three types of adhesives were used: urea–
formaldehyde (UF), phenol–formaldehyde (PF), and HDPE film. UF and PF adhesives were used for
the comparison. The findings of this work indicate that formaldehyde-free HDPE film adhesive gave
values of mechanical properties of alder plywood panels that are comparable to those obtained with
traditional UF and PF adhesives, even though the adhesive dosage and pressing pressure were lower
than when UF and PF adhesives were used. The obtained bonding strength values of HDPE-bonded
alder plywood panels ranged from 0.74 to 2.38 MPa and met the European Standard EN 314-2 for
Class 1 plywood.
36. Melt processing and mechanical property characterization of multi-walled carbon
nanotube/high density polyethylene (MWNT/HDPE) composite films
https://www.sciencedirect.com/science/article/abs/pii/S0008622303003877
High density polyethylene (HDPE) was used as the matrix
material for a carbon nanotube (CNT) polymer composites. This
combination of composite constituents has not been previously
reported in the literature. Multi-wall carbon nanotube
(MWNT)/HDPE composite films were fabricated using the melt
processing method. The composite films with 0, 1, 3 and 5%
nanotube content by weight were analyzed under SEM and TEM to
observe nanotube dispersion. The mechanical properties of the films
were measured by small punch test. Results show increases in the
stiffness, peak load and work to failure for the composite films with
increasing MWNT content.
37. Dimensional stability and mechanical behaviour of wood–plastic composites based on
recycled and virgin high-density polyethylene (HDPE)
https://www.sciencedirect.com/science/article/abs/pii/S135983680700145X
This paper investigated the stability, mechanical properties, and the microstructure
of wood–plastic composites, which were made using either recycled or virgin highdensity polyethylene (HDPE) with wood flour (Pinus radiata) as filler. The post-consumer
HDPE was collected from plastics recycling plant and sawdust was obtained from a local
sawmill. Composite panels were made from recycled HDPE through hot-press moulding
exhibited excellent dimensional stability as compared to that made from virgin HDPE. The
tensile and flexural properties of the composites based on recycled HDPE were equivalent to
those based on virgin HDPE. Adding maleated polypropylene (MAPP) by 3–5 wt% in the
composite formulation significantly improved both the stability and mechanical
properties. Microstructure analysis of the fractured surfaces of MAPP modified composites
confirmed improved interfacial bonding. Dimensional stability and strength properties of
the composites can be improved by increasing the polymer content or by addition of
coupling agent. This project has shown that the composites treated with coupling agents will
be desirable as building materials due to their improved stability and strength properties.
38. What Are the Different Grades of Plywood? https://forestplywood.com/blog/aboutplywood/what-are-the-different-grades-of-plywood/
A-grade plywood: A-grade plywood is the highest quality and is the
most expensive, as most sheets will be free of flaws. If you’re looking for
plywood that is smooth and can be easily painted, this is a great option.
If you’re searching for the right type of plywood for your project, you’ve
probably seen that there are several different grades to choose from.
The variety can be daunting, and the labels can make the process even
more confusing.
39. The different faces of plywood sheets https://www.usply.net/news/the-differentfaces-plywood-sheets/
Grade A plywood sheets are top quality. It’s sanded smooth and is easily
paintable.
This grade may have minor defects, but they should be inconspicuous to the
naked eye. You can sometimes find Grade AA plywood. This is the absolute
highest grade and is used to make furniture, cabinetry, architectural paneling
or molding, making it more expensive and difficult to find.
40. Types of Plywood, Grades, and Sizes https://www.mtcopeland.com/blog/types-of-plywoodgrades-and-sizes
While it was invented in England, plywood was enthusiastically embraced in the
United States beginning in the 19th century. To this day it remains a
primary material in construction and home improvement projects—by one
estimate, more than 680 million cubic feet of plywood are produced each year.
With many houses, plywood forms the walls and floors. It is what keeps a house
standing and the elements outside. After a frame is constructed, it’s necessary to
fill in the spaces between those supports with weather resistant material.
B. Local
41. Plastic Cellphone case using recycled high-density polyethylene
(Rhdpe) Plastic Waste
Over the years, consumption of plastic all round the globe continues to rise.
The unahating increase of populace causes a higher demand of plastic
production, endangering the world with larger amounts of plastic
debris.Roughly 10 percent of the wastes we produce are due to our escalating
production of plastics and its durability (Thompson et al., 2009)