ABS is a family of thermoplastics based on acrylonitrile, butadiene and styrene combined by a variety of methods involving polymerization, graft copolymerization, physical mixtures and combinations thereof. The three constituents provide a balance of properties: the butadiene units imparting good impact strength, the acrylonitrile units affording heat resistance, and the styrene units giving the copolymer its rigidity. ABS can be injection-molded, blow-molded, or extruded.

ABS was patented in 1948 and introduced to commercial markets by the Borg-Warner Corporation in 1954. It is regarded as a good engineering plastic (that is, a substitute for metals in structural parts) and is widely used in appliance housings, luggage, pipe fittings, and automotive interior parts.

Sources:
J. A. Brydson, Plastics Materials, 4th ed., 402-407.
Whittington’s Dictionary of Plastics, 2nd ed., 2.

Commonly known as Acetal, polyoxymethylene (POM) is a thermoplastic produced by the addition polymerization of aldehydes through the carbonyl function, yielding unbranched polyoxymethylene chains of great length. It is commonly produced as both a homopolymer and a copolymer. The material is characterized by good fatigue endurance, resilience, low moisture sensitivity, high solvent and chemical resistance, and good electrical properties.

Acetal is often used for precision automobile and consumer electronic parts that require high stiffness, low friction and excellent dimensional stability. POM is commonly extruded as continuous lengths of round or rectangular section which can be cut and sold as bar or sheet stock for machining. POM is also processed through injection molded and blow-molding techniques.

In 1959, DuPont became the first company to market acetal under the trade name Delrin. The Celanese Corporation quickly followed suit, producing an acetal copolymer known commercially as Celcon in 1962. The Celanese Corporation partnered with other ventures to produce similar products in other countries.  For example, they partnered with Farbwerke Hoechst in Germany to manufacture Hostaform.

 
See also POM Copolymer and POM Homopolymer.

 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 476, 487.
Whittington’s Dictionary of Plastics, 2nd ed., 3.

Acrylic or Polymethyl Methacrylate is a transparent thermoplastic often used as a lightweight or shatter-resistant alternative to glass. Chemically, it is the synthetic polymer of methyl methacrylate. It has outstanding optical clarity and resistance to weathering. PMMA powders can be processed through injection molding, extrusion or compression molding or cast into rods, sheets, or optical lenses. One of the most important early uses for the material was airplane canopies. The material was developed in 1928 in various laboratories, and was first brought to market in the mid-1930s by the Röhm and Haas Company, under the trademark Plexiglas. It has since been sold under many different names, including Lucite and Perspex.

Sources:
J. A. Brydson, Plastics Materials, 4th ed., 362-373.
Jeffrey Meikle, American Plastic: A Cultural History, 85-88.
Whittington’s Dictionary of Plastics, 2nd ed., 251.

The term amino plastic covers a range of resinous polymers produced by the interaction of amines or amides with aldehydes. The two most important variations are Melamine Formaldehyde (MF) and Urea Formaldehyde (UF). The basic resins are clear syrups or white powdered materials which can be dispersed in water to form colorless syrups. Melamine- and Urea- Formaldehyde molding powders are processed on conventional compression and transfer molding equipment. Amino plastics are commonly used as adhesives, surface coatings and in the manufacture of tableware.
 

See also Melamine Formaldehyde (MF) and Urea Formaldehyde (UF).

Sources:
J. A. Brydson, Plastics Materials, 4th ed., 601-617.
Whittington’s Dictionary of Plastics, 2nd ed., 16.

Bakelite is the most famous trade name for a group of plastics known as phenolics, created by condensing phenol with formaldehyde. Bakelite was developed by Dr. Leo H. Baekeland and patented in 1907. It was the first plastic that held its shape after being heated and, as a result, was used for a variety of applications, including ashtrays, saucepan handles, radios, telephones, and electrical insulators.

See also Phenolic
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 601-617.
Whittington’s Dictionary of Plastics, 2nd ed., 25, 231.

See Thiourea Formaldehyde.

Casein is a natural thermosetting material, the result of an acid or the rennet enzyme acting on skim milk. The curds are cleaned and dried into a powder that is mixed with water into dough, which is then then extruded. Formaldehyde is used to harden the material into a bonelike substance. The earliest objects made of casein imitated traditional items made of horn or ivory. Casein was widely used through the 1950's for small hard items such as buttons, buckles, beads, game counters, toys, poker chips, fountain pens, cigarette holders, umbrella and bag handles, novelty items as wells as knitting needles and various adhesives.

Casein has been used as glue since antiquity, but the first patents for the modern materials are from 1885 and 1886 in Germany, with German patents released in America at the same time. The patent for ‘Galalith’  was filed in 1897 by Adolph Spitteler and W. Krische in Upper Bavaria, followed by a patent in Britain in 1889. In England casein was known as ‘Erinoid,’ the trade name of a company that manufactured casein from milk from Ireland in 1913-14. Commercial production began in the United States in 1919.  

Sources:
Sylvia Katz, Plastics: Designs and Materials (London: Studio Vista, 1978), 20-21.
Dominick V. Rosato, Rosato’s Plastics Encyclopedia and Dictionary. (Munich, Vienna, New York, Barcelona: Hanser Publishers, 1993), 91.
Whittington’s Dictionary of Plastics, 2nd ed., 315.

Celluloid is the name commonly applied to material made from Cellulose Nitrate compounded with a plasticizer, usually camphor.
 
See also Cellulose Nitrate.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 52.

Cellulose is derived from stems of plants and trees, especially cotton, and is used in the production of cellulosic plastics.  It is a carbohydrate polymer of high molecular weight comprised of long chains of D-glucose units joined together by beta-1,4-glucosidic bonds.

Cellulose Acetate is a cellulose ester (a derivative of cellulose in which elements of the cellulose chain have been replaced wholly or in part by acidic groups such as nitrate or acetate). It is obtained by the action of acetic acid and acetic anhydride on purified cellulose, most often obtained from cotton linters. For more than a century, cellulose acetate has been the most widely used plastic derived from renewable resources. It is a tough thermoplastic available in a wide range of colors, including transparent, and has been used in the manufacture of films, molding and extrusion compounds, adhesives, fibers and lacquers.
 
Cellulose acetate was first prepared by the French chemist Paul Schützenberger in 1865. In 1904, American chemist George W. Miles developed an acetone-soluble polymer that was used for photographic film. The introduction of injection molding in 1934 transformed cellulose acetate into one of the industry’s leading materials for a variety of inexpensive, brightly-colored consumer items including toys, combs, costume jewelry, buttons, kitchen utensils, golf tees, and radio dials. In the 1940's cellulose acetate was used extensively in the war effort to create airplane windows and non-combatant gas mask eyepieces, since it was a less expensive material than the newly developed acrylic. Post-war production introduced cellulose acetate thread, the first widely-used plastic fiber which came to be known as Rayon.
 
Historically, the major manufacturers of cellulose acetate in the United States have been the Bakelite Corporation, Celanese Celluloid Corporation (under the trade name Lumarith), the Monsanto Chemical Company (Fibestos), Nixon Nitration Works (Nixonite), E. I. Du Pont de Nemours and Company, Inc. (Plastacele), the TennesSEE ALSO Eastman Corporation. (Tenite), and the Hercules Powder Company.
 
See also Cellulosics.
 
Sources:
"Cellulose Acetate," at The Plastics Historical Society (accessed May 14, 2012).
J. A. Brydson, Plastics Materials, 4th ed., 553.
J. Harry DuBois, Plastics. (Chicago: American Technical Society, 1943), 71-78.
Whittington’s Dictionary of Plastics, 2nd ed., 53.

Cellulose Acetate Butyrate (CAB) is an ester of cellulose made by the action of acetic and butyric acids and their anhydrides on purified cellulose. It is used in the manufacture of thermoplastics that are similar in general properties to cellulose acetate but are tougher and have better moisture resistance and dimensional stability.
 
See also Cellulosics.
 
Source:
Dominick V. Rosato, Rosato’s Plastics Encyclopedia and Dictionary. (Munich, Vienna, New York, Barcelona: Hanser Publishers, 1993), 95.

An ester of cellulose made by the action of propionic and acetic acid and anhydrides on purified cellulose. Similar to cellulose acetate butyrate, CAP is compatible with more plasticizers and requires less of them. CAP is commonly processed through extrusion and injection molding.  This tough flexible material is used for products such as eyeglasses frames and goggles, toothbrush handles, pens, flashlight housings, cosmetic containers, and fuel filters.
 
See also Cellulosics.
 
Source:
Dominick V. Rosato, Rosato’s Plastics Encyclopedia and Dictionary. (Munich, Vienna, New York, Barcelona: Hanser Publishers, 1993).

The oldest synthetic plastic, Cellulose Nitrate was first prepared in 1833 by the French chemist Henri Bracconet, who mixed cellulose in the form of sawdust and linen with nitric acid. In 1855 Christian Schonbein repeated the experiment with ordinary paper made from wood cellulose treated with nitric acid. He named the resulting highly-flammable, transparent material cellulose nitrate and patented it as an explosive. John Wesley Hyatt and his brother patented the use of the material as a solid mass in 1869, forming the basis of the plastics molding industry. Often referred to as Celluloid, the plastic was used for items as diverse as billiard balls and hair combs. These products are tough, but flammable, and subject to discoloration in sunlight.
 
See also Cellulosics.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 53.

A family of thermoplastics made by substituting various chemical groups for the hydroxyl groups in the cellulose molecules of cotton linters or wood pulp. Cellulose makes up the cell walls of many plants, but is obtained mostly from wood pulp or cotton for industrial purposes. The most common cellulosics include Cellulose Acetate, Cellulose Acetate Butyrate, Cellulose Acetate Propionate, Cellulose Nitrate and Ethyl Cellulose.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 546-547.
Whittington’s Dictionary of Plastics, 2nd ed., 54.

One of a family of resins obtained by polymerizing the gas ethylene. The first patent on the chlorination of polyethylene was taken out by Imperial Chemical Industries (ICI) in 1938. The introduction of chlorine atoms onto the polyethylene backbone reduces the ability of the polymer to crystallize. The material becomes rubbery at a chlorine level of about 20%, providing the distribution of the chlorine is random. The polymer becomes stiff and then brittle as more chlorine is added. Thermoplastic chlorinated polyethylenes are most often used in blends with other polymers, particularly polyvinyl chloride (PVC).
 
See also Polyethylene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 219-220.
Whittington’s Dictionary of Plastics, 2nd ed., 247-248.

A composite is any article or substance containing or made up of two or more different substances.  In the nineteenth century especially, chemists and product designers experimented with many material combinations and used compression molding and other techniques to create composite billiard balls, children’s’ building blocks and many other consumer items.  Plastic composites usually refer to resinous binders that are used to reinforce various materials including particulate, fibers, flakes and skeletal matrices.  Many plastic objects that are referred to by the resin, such as phenol-formaldehyde, are also composites.

One of a family of resins obtained by polymerizing the gas ethylene. Cross-linking refers to a process in which chemical links are set up between the molecular chains of a plastic. When fully cross-linked by irradiation or by the use of chemical additives, polyethylene is no longer a thermoplastic. If cured during or after molding, it becomes a true thermoset with good tensile strength, electrical properties and impact strength over a wide range of temperatures. Cross-linked PE possesses properties typical of a rubber material, including enhanced heat resistance, and as a result, is often used in the cable industry as a dielectric or sheathing material.
 
See also Polyethylene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 218.
Whittington’s Dictionary of Plastics, 2nd ed., 75, 247-248.

Diallyl Phthalate (DAP) is a thermoset of the allyl family used as a cross-linking monomer for unsaturated polyesters, and as a primary plasticizer for many resins. It polymerizes easily, increasing in viscosity until it finally becomes a clear, infusible solid. The designation DAP is used for both the monomeric and polymeric forms. In the partially polymerized form, DAP is used in the production of thermosetting molding powders, casting resins and laminates.
 
DAP is widely used for critical, high-performance military and commercial electrical components where long-term reliability is demanded and cost is not an overriding factor. DAP compounds resist dimensional change in high-heat soldering environments where competitive materials can warp. DAP products are also highly resistant to solvents, acids, alkalies, fuels, hydraulic fluids, plating chemicals and sterilizing solutions and are inert to fungus growth.

A family of thermosetting resins possessing more than one epoxy group per molecule. Epoxy resins are most often made by condensing epichlorohydrin and bisphenol A. In the early stages of their development, epoxy resins were used almost exclusively for surface coatings, but depending on molecular weight, the resins range from liquids to solid resins. Epoxy resins adhere well to glass fibers and are often used for reinforced plastics. These resins are also useful in electrical composites because their thermal expansion can be tailored to match that of copper.  

 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 666-667.
Whittington’s Dictionary of Plastics, 2nd ed., 117-118.

An ethyl ether formed by reacting cellulose steeped in alkali with ethyl chloride. In the resulting compound, ethyl groups replace the hydrogens in the hydroxyl groups of the cellulose. It is chemically different from other cellulosics, which are esters. Ethyl Cellulose can be injection-molded, extruded, cast into film or used as a coating material. A formulation of ethyl cellulose and oil or plasticizers makes a sort of ethyl rubber, which has a greater resistance to abrasion, ozone and gasoline than natural rubber but less resilience, elongation and resistance to permanent deformation.

See also Cellulosics.

 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 121.

Colorless liquid with mild odor; used as a solvent for resins, lacquers, and nitrocellulose.

Copolymers of large amounts of ethylene with small amounts of vinyl acetate. These copolymers retain many of the properties of polyethylene but have considerably increased flexibility, elongation and impact resistance. They resemble elastomers in many ways but can be processed like thermoplastics.

Source:
Whittington’s Dictionary of Plastics, 2nd ed., 123.

A member of the fluorocarbon family of plastics.  Ethylene-Tetrafluoroethylene (ETFE) is an alternating copolymer of ethylene and tetrafluoroethylene with excellent chemical resistance to acis and organic solvents.  ETFE was first commercialized by DuPont in 1972.

This is a general term for a plastic that is reinforced with cloth, mat, strands, or any other fiber form.

See Glass-Reinforced Plastic

See Fiberglas (Tradename)

A member of the fluorocarbon family of plastics. Fluorinated Ethylene-Propylene (FEP) is a copolymer of tetrafluoroethylene and hexafluoropropylene.

A family of plastics which possess a backbone of carbon and fluorine, including Ethylene-Tetrafluoroethylene (ETFE), Fluorinated Ethylene-Propylene (FEP), Perfluoroalkoxy (PFA), Polytetrafluoroethylene (PTFE) (Teflon), Polyvinylidene Fluoride (PVDF).

Glass Reinforced plastic GRP (also known as fiberglass) is a fiber reinforced polymer made of a plastic matrix reinforced by fine fibers of glass.  GRP is lightweight, extremely strong, and robust. Strength properties are somewhat lower than carbon fiber and it is less stiff, GRP is typically far less brittle, and  much less expensive to produce. The plastic matrix may be epoxy, a thermosetting plastic (most often polyester or vinylester) or thermoplastic.

GRP is commonly used for boats, automobiles, baths, hot tubs, water tanks, roofing, pipes, cladding, casts and external door skins. It's bulk strength and weight properties are also very favorable when compared to metals, and it can be easily formed using molding processes.

Fiber-reinforced plastic for commercial use was extensively researched in the 1930's, especially in the aviation industry.  In 1932, mass production of glass strands was accidentally discovered when a researcher at the Owens-Illinois accidentally directed a jet of compressed air at a stream of molten glass and produced fibers. Owens joined up with the Corning company in 1935 and the method was adapted by Owens Corning to produce its patented "Fiberglas" (one "s").  In 1936, DuPont developed a suitable resin for combining the "Fiberglas" with a plastic. The first ancestor of modern polyester resins is Cyanamid's of 1942.  Peroxide curing systems were used by then.

During World War II GRP it was developed as a replacement for the molded plywood used in aircraft radomes.   Its first main civilian application was for building of boats and sports car bodies, where it gained acceptance in the 1950's. 

See also: "Fiberglass" at Wikipedia (accessed May 5, 2023)

One of a family of resins obtained by polymerizing the gas ethylene. Polymers with densities ranging from about .941 to .965 are called high density polyethylene. The high density types are polymerized at relatively low temperatures and pressures. Whereas the molecules in low density polyethylene are branched and linked in random fashion, those in High Density Polyethylene (HDPE) are linked in longer chains with fewer side branches, resulting in more rigid materials with greater strength, hardness, chemical resistance and higher softening temperature. HDPE is generally used for injection or blow molding. Common products manufactured from HDPE include pipes, milk bottles, seating, wastebaskets, outdoor furniture, luggage, disposable syringes, pallets, shipping pails and containers.
 
See also Polyethylene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 188, 222.
Whittington’s Dictionary of Plastics, 2nd ed., 160-161, 247.

Horn is not a plastic, but it has plastic qualities. It can be formed, shaped and worked into various products, and some of these same manufacturing  techniques were incorporated by the early plastics industry. In the United States horn from western longhorn cattle was most favored for working into combs, utensils and many other products that in time would be replaced first by Celluloid and other cellulose-based plastics, and later by a wide variety of injection molded polymers. The great cattle horns, which were often as much as five feet in spread, were prepared by being cut into sections about six inches long that were then split and boiled in oil.  These cylindrical casings were then pressed flat in hydraulic or manually-operated presses.  The resulting sheets of stock were stamped into comb and hairpin and other blanks.  The blanks were then beveled and rounded on specialized machinery and the resulting products were then scoured with a mild abrasive such as wood ash before distribution and sale.  The entire production cycle was dirty and foul-smelling.

Modified polymers obtained by heating and pressing certain polymers containing carboxylic groups in the presence of metallic ions. Such ionomer resins have low density, high transparency, toughness, resilience, and resistance to greases and solvents. Ionomer resins can be processed by extrusion, blow molding, injection molding, and rotational molding. These resins are commonly used in the fields of skin and blister packaging, bottles, golf ball covers, shoe soles, auto bumper guards, and laminated bags for food and drug items.
 

Source:
Whittington’s Dictionary of Plastics, 2nd ed., 175.

An alloy of aluminum and zinc used for the construction of molds, such as blow molds.  It imparts a high degree of heat conductivity to the mold. Handling and working with kirksite is relatively simple. [Rosato]

One of a family of resins obtained by polymerizing the gas ethylene. Polymers with densities ranging from about .910 to .925 are called low density polyethylene. The low density types are polymerized at very high pressures and temperatures, and the high density types at relatively low temperatures and pressures. The linear low density polyethylenes are intermediate in proprieties and structure to the high pressure and low pressure variants. Like low density polyethylene, Linear Low Density Polyethylene (LLDPE) is used for film applications including trash bags, grocery bags and food packaging. Manufacturing costs for LLDPE are lower than for low density polyethylene due to reduced energy requirements and maintenance costs.
 
See also Polyethylene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 188, 222.
Whittington’s Dictionary of Plastics, 2nd ed., 247.

A relatively unique class of partially crystalline aromatic polyesters based on p-hydroxybenzoic acid and related monomers. Liquid crystal polymers are capable of forming regions of highly ordered structure while in the liquid phase. However, the degree of order is somewhat less than that of a regular solid crystal. Typically LCPs have outstanding mechanical properties at high temperatures, excellent chemical resistance, inherent flame retardancy and good weatherability. Liquid crystal polymers come in a variety of forms from sinterable high temperature to injection moldable compounds.
 
A number of liquid crystal polymers (LCPs) were produced in the 1970s which displayed order in the melt (liquid) phase analogous to that exhibited by non-polymeric liquid crystals. However, the commercial introduction of liquid crystal polymer resins did not occur until 1984, at that time liquid crystal polymers could not be injection molded. Today, liquid crystal polymers can be melt processed on conventional equipment at fast speeds with excellent replication of mold details and efficient use of regrind.
 
Source:
plastics.ides.com/generics/17/liquid-crystal-polymer-lcp

One of a family of resins obtained by polymerizing the gas ethylene. Polymers with densities ranging from about .910 to .925 are called low density polyethylene. The low density types are polymerized at very high pressures and temperatures. In Low Density Polyethylene (LDPE), the ethylene molecules are linked in random fashion, with the main chains having side branches. This branching prevents the formation of a closely knit pattern, resulting in a material that is relatively soft, flexible and tough, and which will withstand moderate heat. Most LDPE is used for film applications such as trash bags, grocery bags and food packaging.
 
See also Polyethylene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 188.
Whittington’s Dictionary of Plastics, 2nd ed., 189, 247.

Melamine Formaldehyde resins are thermosetting resins of the Amino Plastics family made by reacting melamine with formaldehyde. The lower molecular weight uncured melamine resins are water soluble syrups, used for impregnating paper, laminating, etc. The higher molecular weight resins are powders, widely used for plastic tableware.

See also Amino Plastics

Source:
Whittington’s Dictionary of Plastics, 2nd ed., 195.

Nylon is the generic name for all long-chain polyamides that have recurring amide groups (-CO-NH-) as an integral part of the main polymer chain. There are various different types of nylon depending on the nature of those chains. Nylons are identified by numbers denoting the number of carbon atoms in the polymer chain derived from specific constituents, those from the diamine being given first. The second number, if used, denotes the number of carbon atoms derived from a diacid. Nylon 6/6 and Nylon 6 are the most popular, followed by Nylon 11 and Nylon 12.

The first polyamide was discovered by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station in 1935. Nylon was first used commercially for toothbrush bristles in 1938 and then to produce silk-like stockings in 1940. Polyamides replaced silk in many products during World War II, including parachutes and flak vests. It was also used in vehicle tires. In the 1950's inventor and harpist Melville Clarke, working with DuPont engineers, designed the first nylon strings of instruments. Today, nylon fibers are used in fabrics, bridal veils, carpets, musical strings, and rope. Solid nylon is used for mechanical parts including machine screws, gears and other low-to medium-stress components previously cast in metal. It is also commonly used for everyday items such as hair combs and sunglass frames. Engineering-grade nylon is processed by extrusion, casting, and injection molding. Nylon has outstanding wear resistance and low frictional properties. It also has very good temperature, chemical and impact properties. Its one weakness is a propensity to absorb moisture and thus have poor dimensional stability.
 
Sources:
"Nylons" at Polymer Science Learning Center, Department of Polymer Science, The University of Southern Mississippi.
Whittington’s Dictionary of Plastics, 2nd ed., 215.

Nylon is the generic name for all long-chain polyamides that have recurring amide groups (-CO-NH-) as an integral part of the main polymer chain. Nylon 11 is produced by condensation polymerization of the monomer 11-amino-undecanoic acid, a derivative of castor oil. It is available in the form of fine powders for rotation molding and other powder processes and in the form of pellets for extrusion or molding. Like Nylon 12, it has properties intermediate between those of Nylon 6 and polyethylene: good impact strength, hardness and abrasion resistance.

See also Nylon.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 216.

Nylon is the generic name for all long-chain polyamides that have recurring amide groups (-CO-NH-) as an integral part of the main polymer chain. Nylon 12 is produced by the polymerization of lauric lactam or cyclododecalactam, with 11 methylene units between the linking groups in the polymer chain. Like Nylon 11, it has properties intermediate between those of Nylon 6 and polyethylene: good impact strength, hardness and abrasion resistance.
 
See also Nylon.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 216.

Nylon is the generic name for all long-chain polyamides that have recurring amide groups (-CO-NH-) as an integral part of the main polymer chain. Nylon 6 (polycaprolactam) is a semicrystalline polyamide formed by ring-opening polymerization of caprolactam and is not a condensation polymer. Nylon 6  was developed by Paul Schlack at IG Farben to reproduce the properties of Nylon 6/6 without violating the patent on its production. It was given the trademark Perlon in 1952. Nylon 6 is especially used in fiber, thread and string applications such as toothbrushes, sutures, strings for acoustical musical instruments, ropes, filaments, nets, and tire cords. Competition between Nylon 6 and Nylon 6/6 has shaped the economics of the synthetic fiber industry.
 
See also Nylon.
 
Sources:
"Nylons" at Polymer Science Learning Center, Department of Polymer Science , The University of Southern Mississippi.
Whittington’s Dictionary of Plastics, 2nd ed., 215-216.

Nylon is the generic name for all long-chain polyamides that have recurring amide groups (-CO-NH-) as an integral part of the main polymer chain. Nylon 6/6 was first prepared by Wallace Carothers in 1936 and is made by condensing hexamethlyenediamine with adipic acid. Nylon 6/6 is the strongest of the nylons over the widest range of temperature and moisture. As a result, it is the most widely used nylon variety, especially for fibers.
 
See also Nylon.
 
Sources:
"Nylons" at Polymer Science Learning Center, Department of Polymer Science , The University of Southern Mississippi.
Whittington’s Dictionary of Plastics, 2nd ed., 216.

A member of the fluorocarbon family of plastics, in which perfluoroaklyl side chains are connected to the carbon-fluorine backbone of the polymer through flexible oxygen linkages. PFA was introduced by Du Pont in 1972. These resins can be easily processed by extrusion and injection molding.
 
See also Fluorocarbons.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 229.

See Polyethylene Terephthalate (PET)

Phenol-furfural is produced by reacting furfural, a distillation of oat hulls, corn cobs and other organic waste, with formaldehyde, to make a resin suitable for compression and transfer molding into electrical items such as thermostats and magneto heads for aircraft.  In 1923 Durite Plastics, Inc. began production of the phenol-furfural Durite, which was also widely used for paints.

Source:
Katz, Sylvia, Plastics: Designs and Materials (London: Studio Vista, 1978), 23.

Phenolics are a family of thermosetting resins made by reacting a phenol with an aldehyde, most commonly formaldehyde. The resulting plastics are hard, brittle, opaque, and have good electrical and heat resistance. In the uncured and semi-cured condition, phenolic resins are used as adhesives, casting resins, potting compounds and laminating resins. Through compression molding and transfer molding, phenol formaldehyde thermoset plastics are formed into a large variety of products such as ashtrays, lamp holders, bottle caps, saucepan handles, electrical plugs and switches and electrical iron parts. Bakelite is the most famous trade name for phenolics and the terms are often used interchangeably.
 
See also Bakelite
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 231.

A thermoplastic resin made by the polymerization of an acrylic compound such as methyl methacrylate.

Source:
Whittington’s Dictionary of Plastics, 2nd ed., 240.

A family of polymers based on the combination of trimellitic anhydride with aromatic diamines. These resins are used for laminating, prepregs and electrical components. Molding resins that behave as thermoplastics can be produced by thermally curing and modifying these polymers.  These molding resins can be processed by compression, extrusion or injection molding.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 241.

A group of crystalline polymers based on butene-1, which were first developed in 1965. Their properties are similar to those of polypropylene and linear polyethylene, with superior toughness, creep resistance and flexibility. Early applications were in the areas of pipes, wire coating, gaskets and heavy-duty packaging films.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 243.

Polybutylene terephthalate (PBT) is a thermoplastic polyester produced by the polycondensation of dimethyl terephthalate and butanediol whose main features are stability under load, low surface friction, low water absorption, and good electrical properties. It is used in a wide range of applications including electrical and automotive components due to its good insulation properties and its resistance to automotive fluids and other chemicals, such as ethers, alcohols, and weak acids and bases.

PBT products are mostly injection molded, but they can also be extruded or blow molded. PBT has a high rate of mold shrinkage (2%) but this can be reduced by adding glass filler, though glass fibers can also cause uneven shrinkage. Uniform wall thickness is recommended to avoid warping, and corners should be rounded because PBT is notch sensitive. Parts molded in PBT can be joined by ultrasonic welding, spin welding, and adhesives. 
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 243.

Polymers derived from the direct reaction between aromatic and aliphatic dihydroxy compounds with phosgene, or by the ester exchange reaction with phosgene-derived precursors. When the aromatic dihydroxy is bisphenol-A, the resulting polycarbonate is thermoplastic – the most commonly used form. Such polycarbonates have high impact strength, good heat resistance, low water absorption and good electrical properties. They are transparent, and may be injection molded, extruded, thermoformed or blow molded. Applications include optical purposes, dentures, stain-resistant dinnerware, packages for foodstuffs, electrical components and precision parts for instruments and household appliances.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 243-244.

Generic name for a manufactured fiber in which the fiber-forming substance is any long chain of synthetic polymer composed of at least 85% by weight of an ester of a dihydric alcohol and terephthalic acid.

Polyester is a general term encompassing all polymers in which the main polymer backbones are formed by the esterification condensation of polyfunctional alcohols and acids. Thermoplastic polyesters become pliable above a specific temperature and return to a solid state upon cooling. Common examples include Polybutylene Terephthalate (PBT) and Polyethylene Terephthalate (PET).

See Polyester Thermoplastic--Polyethylene Terephthalate (PET) 

See also Polyester Thermoset.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 244-245.

Polyester is general term encompassing all polymers in which the main polymer backbones are formed by the esterification condensation of polyfunctional alcohols and acids. Thermoset polyesters form irreversible chemical bonds during the curing process.
 
See also Polyester Thermoplastic.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 244-245.

Polyetheretherketone (PEEK) is a high-strength, radiation-resistant engineering plastic whose structure combines both ether and ketone groups. PEEK is thermally stable and highly resistant to chemicals. Principal uses are in machine parts, nuclear power-plant equipment, automobile parts, aerospace components, cable insulation, and pump parts.

Source:
"Major Industrial Polymers," Britannica Academic Edition

Polyetherimide (PEI) is a strong, high-temperature, amorphous, thermoplastic material characterized by having both ether links and imide groups in its molecule. PEI was first commercialized in 1982 by General Electric (now Sabic Innovative Plastics), and known by its trade name, Ultem.
 
Source:
Handbook of Plastics Materials & Technology, 1st ed., 263.
Whittington's Dictionary of Plastics, 3rd ed., 378.

A high-temperature engineering thermoplastic consisting of repeating phenyl groups linked by thermally stable ether and sulfone groups. The material has good transparency and flame resistance. Both polymer and reinforced grades are available in granule form for extrusion and injection molding.  Unreinforced grades are used in high temperature electrical applications, bakery oven windows and medical components. Reinforced grades are used for radomes, structural aircraft and aerospace components, and auto parts.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 246.

Polyethylenes are a family of resins obtained by polymerizing ethylene gas, creating a thermoplastic polymer consisting of long hydrocarbon chains. Polyethylene is made in different grades. By varying the catalysts and methods of polymerization, properties such as density, melt index, crystallinity, degree of branching and cross-linking, and molecular weight distribution can be regulated over wide ranges. Low molecular weight polymers of ethylene are fluids used as lubricants; medium weight polymers are waxes miscible with paraffin; and the high molecular weight polymers are the familiar, rough, leathery resins used in the plastics industry in the highest volume of all plastics. When fully cross-linked by irradiation or by the use of chemical additives, polyethylene is no longer a thermoplastic. When cured during or after molding, it becomes a true thermoset with good tensile strength, electrical properties and impact strength over a wide range of temperatures.
 
Many iconic plastic products, such as Tupperware, are made of polyethylene. Since the 1940's, polyethylene has been most visible in packaging, especially as plastic bags and plastic film. Polyethylene foam is used in packaging, vibration damping and insulation, as a barrier or buoyancy component, or as material for cushioning.
 
Polyethylene was first synthesized by the German chemist Hans von Pechmann who prepared it by accident in 1898 while heating diazomethane. His colleagues Eugen Bamberger and Friedrich Tschirner characterized the white, waxy, substance and recognized that it contained long -CH2- chains and termed it polymethylene. The first industrially practical polyethylene synthesis was discovered (again by accident) in 1933 by Eric Fawcett and Reginald Gibson at the Imperial Chemical Industries (ICI) works in Northwich, England.

See also Chlorinated PE (CPE), Cross-linked PE (XLPE), High Density PE (HDPE), Linear Low Density PE (LLDPE), Low Density PE (LDPE), and Ultra High Molecular Weight PE (UHMWPE).
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 187-189.
Whittington’s Dictionary of Plastics, 2nd ed., 247-248.

Polyethylene Terephthalate (PET) is a thermoplastic polyester produced by condensing ethylene glycol and terephthalic acid.  The resulting molten, viscous mass can be spun directly into fibers or solidified for later processing. It can be blow-molded into disposable beverage bottles or extruded into photographic film and magnetic recording tape. PET is extremely hard, wear-resistant, dimensionally stable, resistant to chemicals and has good dielectric properties.
 
J. Rex Whinfield and James T. Dickson of the Calico Printers Association in England first prepared PET in the course of a study of phthalic acid begun in 1940.  Because of restrictions during World War II, patent specifications for the new material were not immediately published.  By 1945 DuPont had independently developed a practical preparation process from terephthalic acid, and in 1953 the company began to produce Dacron fiber. PET soon became the most widely produced synthetic fiber in the world. In the 1970's, improved stretch-molding procedures were devised that allowed PET to be made into durable crystal-clear beverage bottles—an application that soon became second in importance only to fiber production. PET is also the most widely recycled plastic.
 
Sources:
Britannica Academic Edition.
Whittington’s Dictionary of Plastics, 2nd ed., 248.

In 1963, DuPont developed the first polyimides which were condensation polymers derived from pyromellitic dianhydride and aromatic diamines. Due to rings of four carbon atoms bound tightly together, the material is said to possess a greater resistance to heat than any other unfilled organic material. Thermoplastic polyimide filled with glass, boron, or graphite fibers can be molded into high-strength structural components.  Solutions of thermoplastic polyimide are used as laminating varnish to produce radomes, printed circuit boards and other components requiring fire resistance, good electrical properties and strength at high temperatures.  
 
Sources:
Whittington’s Dictionary of Plastics, 2nd ed., 249

A polyolefin first reported by G. Natta in 1955 but not introduced commercially until 1966 when Imperial Chemical Industries (ICI) marketed the resin under the tradename TPX. Polymethyl Pentene (PMP) is available both as a monomer and a polymer. The polymers are supplied as free-flowing powders or as compounded granules and can be process by injection molding, extrusion or blow molding. Properties of the resins are very low density, high light transmission, melting point over 460°F, rigidity and tensile properties similar to polypropylene, good electrical properties, and high chemical resistance. PMP is used for hospital and laboratory ware, extrusion-coated paper, high intensity internal lighting fixtures, car body and radiator plugs, textile bobbins, sight glasses and high frequency electrical components.
 
Sources:
Whittington’s Dictionary of Plastics, 2nd ed., 251.

See Acrylic

See Acrylic (Polymethyl Methacrylate) (PMMA)

See Acetal (Polyoxymethylene) (POM)

Polyphenylene Ether (PPE) was developed in response to marketplace demands for a second source for General Electric’s Polyphenylene Oxide (PPO) (Noryl) The basic polymerization, properties, and application for PPE are similar to PPO. Borg Warner Chemicals introduced PPE in 1982 but their plastics business was purchased by General  Electric in 1988. As a result, the PPE material, known as Prevex, faded from the market.
 
Source:
Handbook of Plastic Materials & Technology, 1st ed., 395.
Glenn Beall

A thermoplastic, linear, non-crystalline polyether obtained by the oxidative polycondensation of 2,6 dimethylphenol in the presence of a copper-amine complex catalyst. These resins have a useful temperature range from less than -275°F to 375°F (with intermittent use up to 400°F), excellent electrical properties, unusual resistance to acids and bases. Polyphenylene Oxide (PPO) can be processed through extrusion or injection molding. PPO was discovered in 1956 by John Hay and introduced in 1965-1966 by General Electric (now Sabic Innovative Plastics) under the tradename Noryl.
 
Sources:
Handbook of Plastic Materials & Technology, 1st ed., 409.
Whittington’s Dictionary of Plastics, 2nd ed., 253.

A crystalline polymer having a symmetrical, rigid backbone chain consisting of recurring para-substituted benzene rings and sulfur atoms. A variety of different grades suitable for slurry coating, fluidized bed coating, electrostatic spraying as well as injection and compression molding are offered by Phillips Petroleum Co. under the trade mark Ryton. The polymers exhibit outstanding chemical resistance, thermal stability and fire resistance. The extreme inertness to organic solvents, inorganic slats and bases make for outstanding performance as a corrosion resistant coating suitable for food contact use.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 253.

An engineering thermoplastic developed by Union Carbide and introduced in 1977 under the tradename Radel. Polyphenylene Sulfone (PPSU) is chemically similar to Polysulfone, but has higher impact resistance along with good heat resistance, good chemical resistance, low creep and good electrical properties.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 253.

Polypropylene (PP) is a thermoplastic resin made by polymerizing propylene with suitable catalysts, generally aluminum alkyl and titanium tetrachloride mixed with solvents. PP has a density of approximately 0.90, among the lowest of all plastics. Like polyethylene, properties of polypropylene vary widely according to molecular weight and method of preparation. Grades of PP suitable for molding generally possess good resistance to heat and chemicals and good electrical properties.
 
Polypropylene is most commonly processed by injection molding. It is used in a wide variety of applications including packaging and labeling, textiles (e.g., ropes, thermal underwear and carpets), dishwasher safe food containers, laboratory equipment, loudspeakers, automotive components, and polymer banknotes. Unlike nylon, which is also used as a fiber for carpeting, polypropylene doesn't soak up water, making it preferred where moisture is a problem. PP has excellent fatigue resistance and is therefore widely used in “living hinges,” (first developed in 1962) for flop-top container tops, boxes, medical forceps and many other applications. For the hinge, it is important that the chain molecules are situated across the hinge to provide maximum strength.
 
The origins of polypropylene have been contested. According to historian Jeffrey Meikle, in the 1950's "researchers at Du Pont, Phillips, Standard Oil, Hercules, and Montecatini in Italy all laid claim to another polymer even stronger than linear polyethylene but similar in derivation and structure." Giulio Natta (who with Karl Ziegler shared the Nobel Prize in chemistry in 1963) was long credited with inventing polypropylene. In the mid-1950's he polymerized propylene to a crystalline isotactic polymer which was subsequently developed for industrial application by Montecatini chemists. It wasn't until 1983, however, when after a quarter century of litigation, Phillips received a patent for the plastic and its researchers, J. Paul Hogan and Robert L. Banks, were recognized as polypropylene’s inventors.
 
See also PP Copolymer and PP Homopolymer.
 
Sources:
"Polypropylene," Wikipedia (accessed May 22, 2012).
Jeffrey L. Meikle, American Plastic: A Cultural History (New Brunswick, NJ: Rutgers University Press, 1995), 191.
Peter J. T. Morris, Polymer Pioneers: A Popular History of the Science and Technology of Large Molecules (Chemical Heritage Foundation, 2005), 76.
Jay L. Vermillion, "How to make the polypropylene hinge," Modern Plastics (July 1962), 121-122, 126, 188-190.

See Styrene (Polystyrene) (PS)

A family of sulfur-containing thermoplastics introduced in 1965 by Union Carbide, based on benzene rings or phenylene units linked by three different chemical groups – a sulfone group, an ether linkage and an isopropylidene group. Each of these three linking components acts as an internal stabilizer. Polysulfones are characterized by high strength, the highest service temperature of all melt-processable thermoplastics, low creep, good electrical characteristics, transparency, self-extinguishing properties, and resistance to greases, many solvents and chemicals.  They may be processed by extrusion, injection molding and blow molding.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 255.

The oldest member of the Fluorocarbon family of plastics. Polytetrafluoroethylene (PTFE) was developed by Dr. R. J. Plunkett in 1938 and marketed as Teflon. It is made by polymerizing tetrafluoroethylene. PTFE is characterized by its extreme inertness to chemicals, very high thermal stability, low coefficient of friction, and ability to resist adhesion to almost any material, a property developed early on by DuPont in the creation of Teflon cookware. Its high melt viscosity makes it difficult to mold by extrusion or injection molding. PTFE is often used as coating, or molded using the sinter molding process, in which plastic particles are welded together at temperatures just below the melting point.
 
See also Fluorocarbons.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 255.

A large family of polymers with widely varying properties and uses, all based on the reaction product of an organic isocyanate with compounds containing a hydroxyl group. The properties of polyurethanes may be varied within wide limits to suit the desired application. They may be thermosetting or thermoplastic, rigid or soft and flexible, cellular or solid.
 
See also PUR Thermoplastic and PUR Thermoset.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 256-7.

Polyvinyl Chloride (PVC) is the most important member of the vinyl plastics family. It is made by polymerization of vinyl chloride with peroxide catalysts. The pure polymer is hard, brittle and difficult to process, but it becomes flexible when plasticizers are added. PVC is compatible with many different kinds of additives and can be clear or colored; rigid or flexible. The material is widely used for window frames, pipes, medical devices, blood storage bags, cable and wire insulation, resilient flooring, roofing membranes, stationary, automotive interiors and seat coverings, fashion and footwear, packaging, cling film, credit cards, synthetic leather and other coated fabrics.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 257-8.

A member of the fluorohydrocarbon resin family. Polyvinylidene Fluoride (PVDF) is thermally stable at high temperatures. It is stronger and more abrasion resistant than other fluorocarbons and is easier to process on conventional thermoplastic equipment. PVDF is commonly used in electrical insulation, pipes and other chemical process equipment, and coatings for industrial and commercial buildings.
 
See also Fluorocarbons.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 258.

Variation of Polyoxymethylene (POM) denoting a polymer of two chemically distinct monomers.

See also Acetal (Polyoxymethylene) (POM).
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 71.

Variation of Polyoxymethylene (POM) polymer resulting from the polymerization of a single monomer.

See also Acetal (Polyoxymethylene) (POM).
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 162.

Variation of Polypropylene (PP) denoting a polymer of two chemically distinct monomers.
 
See also Polypropylene (PP).
 
Source:

Whittington’s Dictionary of Plastics, 2nd ed., 71.

Variation of Polypropylene (PP) polymer resulting from the polymerization of a single monomer.
 
See also Polypropylene (PP).
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 162.

A variety of styrene (vinyl benzene) polymer. Polystyrene Acrylonitrile (SAN) is formed by the polymerization of styrene and acrylonitrile. The resulting copolymers have the transparency of polystyrene but with improved stress cracking and solvent resistance. They are prepared by emulsion, suspension, or bulk polymerization processes. SAN's main features are clarity, rigidity, high glass, and low cost versus many other engineering plastics. It is much like ABS (Acrylonitrile Butadiene Styrene) without the impact-resistant butadiene rubber. Thus, it is not noted for its impact strength. The content ratio of the acrylonitrile monomer varies from 20-32% creating different grades and property combinations. The acrylonitrile component provides heat resistance in the range of 200-210°F and chemical resistance to common industrial and household chemicals. Overall, however, chemical resistance of SAN is less than many competing resins. SAN is usually injection molded, but it can also be extruded or blow molded.
 
See also Styrene.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 7.

A variety of styrene (vinyl benzene) polymer. Block copolymers possess chains composed of shorter homo-polymeric chains or “blocks,” which are linked together. These blocks can be either regularly alternating or random. Such copolymers usually have higher impact strengths than either of the homopolymers or physical mixtures of the two homopolymers.
 
See also Styrene.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 162.

A variety of styrene (vinyl benzene) polymer. PS Butadiene (SB) was first introduced in 1965 as an elastic, amorphous, thermoplastic material characterized by a linear block copolymer structure of polystyrene and butadiene. SB provides many rubber-like properties and can be processed by all known thermoplastic manufacturing techniques.
 
See also Styrene.
 
Source:
Handbook of Plastic Materials & Technology, 1st ed., 576, 617.
Modern Plastics Handbook, 1st ed., 169.
Whittington’s Dictionary of Plastics, 3rd ed., 486.

A variety of styrene (vinyl benzene) polymer. In general purpose grade polystyrene, a balance is attempted to obtain good heat resistance, reasonably high setting up temperature, good flow properties and reasonable impact strength.

See also Styrene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 393.
Whittington’s Dictionary of Plastics, 2nd ed., 254.

A variety of styrene (vinyl benzene) polymer. Polystyrene has outstanding electrical properties, good thermal and dimensional stability, and is resistant to staining. However, it is somewhat brittle, and is often copolymerized or blended with other materials to obtain desired properties. High-impact grades are produced by adding rubber or butadiene copolymers.
 
See also Styrene.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 398-99.
Whittington’s Dictionary of Plastics, 2nd ed., 254.

A variety of styrene (vinyl benzene) polymer. PS Maleic Anhydride (SMA) was introduced in the 1930s.  It did not find a use in the plastics industry until it was copolymerized with polystyrene and commercialized by Sinclair Petrochemicals in the 1960s. This amorphous, thermoplastic, alternating copolymer has a higher service temperature than polystyrene or ABS. Increased impact strength is achieved by polymerizing the monomers in the presence of polybutadiene creating a terpolymer. SMA automotive dashboards were commercialized in 1972.
 
See also Styrene.

 
Sources:
Handbook of Plastic Materials & Technology, 1st ed., 591.
Dominick V. Rosato, Rosato’s Plastics Encyclopedia & Dictionary, 1st ed., 728.

A member of the polyurethane family of polymers, all based on the reaction product of an organic isocyanate with compounds containing a hydroxyl group. In their final state, thermoplastics are capable of being repeatedly softened by an increase of temperature and hardened by a decrease of temperature.
 
See also Polyurethane (PUR)
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 256-7 and 314.

A member of the polyurethane family of polymers, all based on the reaction product of an organic isocyanate with compounds containing a hydroxyl group. In their final state, thermosetting plastics are substantially infusible and insoluble. They cannot be resoftened by heat.
 
See also Polyurethane (PUR)
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 256-7 and 314.

See Polyvinyl Chloride (PVC)

See Polyester Thermoplastic  and Polyester Thermoset

Shellac was developed as one of the first natural plastics and is mentioned in ancient Indian texts. It is secreted by the laccifer lacca (coccus lacca), a beetle native to India and Malaya, and deposited on the tree twigs, after which is it collected, washed and purified by melting and filtering. It is then formed into thin sheets and fragmented in flakes for the use in varnishes, coatings and other applications. Shellac can be made more substantial when fillers are added, as was the case with the manufacturer of daguerreotype cases in the nineteenth century and recording discs (records) in the twentieth. Fillers include wood flour, asbestos, ground limestone and other materials. Shellac is easy to mold, inexpensive, and the scrap can be recycled, and because it can reproduce details of a mold extremely well, it became the standard materials for all records before 1930. Shellac was also widely used for electrical insulation because it can withstand extreme temperature change and resists water and oil. 

Source:
Sylvia Katz, Plastics: Designs and Materials (London: Studio Vista, 1978), 19-20.

Silicones are a family of semi-organic polymers comprising chains of alternating silicon and oxygen atoms, modified with various organic groups attached to the silicon atoms. Depending on the nature of the attached organic groups and the extent of cross-linking between the molecules, the polymers may be fluids, elastomers, or solid resins. Silicone fluids are used as lubricants, mold release agents, heat transfer fluids and water-repellant coatings. The elastomers, often called silicone rubbers and reinforced with inorganic fillers or fibers, are vulcanizable and offer superior resistance to high temperatures and weathering. Silicon resins possess good electrical properties and strength at high temperatures and are widely used for encapsulating and potting electrical components and in reinforced laminates. Solvent solutions are used in coatings and varnishes.
 
Source:
Whittington’s Dictionary of Plastics, 2nd ed., 288-89.

ilicone rubber is also known as silicone elastomer.  This was first produced in 1940 and continues to be used in applications where retention of properties at both high and low temperatures is needed. 

Soy fiber and soy flour could be mixed to produce a simple fiberboard produced under heat and pressure, probably extruded in sheets.  Fiberboard was first made in the 1920s and is now a major material for packaging, construction, furniture, displays, paneling, and other uses. Today, medium density fiberboard (MDF) is a widely used material primarily composed of lignocellulosic fibers combined with a synthetic resin or other suitable bonding system and bonded together under heat and pressure. Fiberboard is often seen as an environmentally friendly material because it recycles waste materials, but the use of formaldehyde resins can cause air-quality problems, especially in homes, that can lead to health problems. Researchers today are again focusing on soy-based plastics, especially the use of soy proteins as "truly green" bonding agents for lignocellulosic fibers.

A family of hard, rigid, transparent thermoplastics which emit a characteristic metallic ring when dropped. Styrenes are free from odor and taste and burn with a sooty flame. Polystyrene has outstanding electrical properties, good thermal and dimensional stability, and is resistant to staining. However, it is somewhat brittle, and is often copolymerized or blended with other materials to obtain desired properties. High-impact grades are produced by adding rubber or butadiene copolymers. Heat resistance is improved by including some alpha- or methyl styrene copolymers. Copolymerization with methyl methacrylate improves light stability, and copolymerization with acrylonitrile increases resistance to chemicals. Styrene polymers and copolymers possess good flow properties at temperatures safely below degradation ranges, and can be easily extruded, injection-molded or compression molded.  Polystyrene was widely used after World War II for injection molded toys and a wide variety of household items.  Today it is used for yogurt containers, refrigerator linings, vending cups, bathroom cabinets, toilet seats and tanks, closures, instrument control knobs and a host of other products.
 
See also PS Acrylonitrile, PS Block Copolymer, PS Butadiene, PS General Purpose, PS High Impact, and PS Maleic Anhydride.
 
Sources:
J. A. Brydson, Plastics Materials, 4th ed., 395.
Whittington’s Dictionary of Plastics, 2nd ed., 254.

A member of the amino plastics family made by the condensation of thiourea with formaldehyde. The resin was developed in the 1920s by Charles Rossitor of the British Cyanides Company. The resin was used to make "Beetle" tableware, whose unusual name was derived from the trademark of the British Cyanides Company (a beetle). Similar tableware was marketed under the name Bandalista and Birmite. By the mid-1930’s new urea formaldehyde products with similar qualities of durability but with better water resistance and no chemical odor had displaced those made of thiourea formaldehyde.
 
See also Amino Plastics

 
Sources:
Blackall, A.C. "Molded Dishes from New Synthetic Resin," Plastics & Molded Products Vol 3:11 (Nov. 1927), 606-607.
Whittington’s Dictionary of Plastics, 2nd ed., 315.

One of a family of resins obtained by polymerizing the gas ethylene. Ultra-high molecular weight polyethylenes (UHMWPE) have molecular weights in the 1.5 to 3.0 million range and are very difficult to process.
 
See also Polyethylene.
 
Sources:
Whittington’s Dictionary of Plastics, 2nd ed., 247, 326.

Urea Formaldehyde resins are thermosetting resins of the Amino Plastics family made by reacting urea with formaldehyde. Available in a wide range of colors, Urea Formaldehyde is used to manufacture items such as buttons, toilet seats and hair dryer housings but is most commonly used as an adhesive by the particle board, plywood and furniture industries.

See also Amino Plastics.

Source: J. A. Brydson, Plastics Materials, 4th ed., 601-617.

See Polyvinyl Chloride (PVC)

A unique family of impact modified polymethyl methacrylates (acrylics) that retain their transparency. These are physical blends of a glassy terpolymer and a grafted rubbery polymer that are rigid and tough with far greater impact strength than the other transparent styrene-based polymers and copolymers. XT Polymers are thermoplastic, amorphous materials that are normally injection molded, extruded, or thermoformed. They were first commercialized by American Cyanamid’s Cyro Industries in a joint venture with Rohm GmbH.
 
Sources:
Handbook of Plastic Materials & Technology, 1st ed., 665, 672.
Rosato’s Plastics Encyclopedia & Dictionary, 1st ed., 814.