Definitions of Plastic Resins

Acetal
An engineering thermoplastic produced by the polymerization of purified formaldehyde [CH2O] into both homopolymer and copolymer types. Typical applications are found in consumer products, automotive parts, and industrial machinery parts.

Acrylics
A family of thermoplastic resins of acrylic esters [CH2CHCOOR] or methacrylic esters [CH2C(CH3)COOR]. The acrylates may be methyl, ethyl, butyl, or 2-ethylhexyl. Usual methacrylates are the methyl, ethyl, butyl, laural and stearyl. Typical applications are found in lighting fixtures, glazing and automotive parts.

Acrylonitrile-Butadiene-Styrene (ABS)
A class of thermoplastic terpolymers including a range of resins, all prepared with usually more than 50% styrene [C6H5CHCH2] and varying amounts of acrylonitrile [CH2CHCN] and butadiene [CH2CHCHCH2]. The three components are combined by a variety of methods involving polymerization, graft copolymerization, physical mixtures and combinations thereof. Typical applications are found in appliances, automotive parts, pipe, business machine and telephone components.

Alkyds
Thermosetting unsaturated polyester resins produced by reacting an organic alcohol with an organic acid, dissolved in and reacted with unsaturated monomers such as styrene [C6H5CHCH2], diallyl phthalate [C6H4(COOCH2CHCH2)2], diacetone acrylamide [CH3COCH2C(CH3)2CHCHCONH2] or vinyl toluene [CH2CHC6H4CH2]. Typical applications are found in electrical uses, automotive parts, and as coatings.

Cellulosics
A family of thermoplastic resins manufactured by chemical modification of cellulose [(C6H10O5)n]. Included are: cellophane-regenerated cellulose made by mixing cellulose xanthate [ROCSSH] with a dilute sodium hydroxide [NaOH] solution to form a viscose, then extruding the viscose into an acid bath for regeneration; cellulose acetate-an acetic acid ester [CH3COOC2H5] of cellulose; cellulose acetate butyrate-a mixed ester produced by treating fibrous cellulose with butyric acid [CH3CH2CH2COOH], butyric anhydride [(CH3CH2CH2CO)2O], acetic acid [CH3COOH] and acetic anhydride [(CH3CO)2O] in the presence of sulfuric acid [H2SO4]; cellulose propionate- formed by treating fibrous cellulose with propionic acid [CH3CH2CO2H] and acetic acid and anhydrides in the presence of sulfuric acid; cellulose nitrate-made by treating fibrous cellulosic materials with a mixture of nitric [HNO3] and sulfuric acids. Typical applications are found in packaging, consumer products, and automotive parts.

Coumarone-Indene
Thermoplastic resin obtained by heating mixtures of coumarone [C8H6O] and indene [C6H4CH2CHCH] with sulfuric acid [H2SO4] to promote polymerization. These resins have no commercial applications when used alone. They are used primarily as processing aids, extenders and plasticizers with other resins in asphalt floor tile.

Diallyl Phthalate (DAP)
The term DAP is used both for the monomeric and polymeric forms. The monomer [C6H4(COOCH2CHCH2)2] is used as a cross-linking agent in unsaturated polyester resins. As a polymer, it is used in the production of thermosetting molding powders, casting resins and laminates.

Epoxy
Thermosetting resins that, in the uncured form, contain one or more reactive epoxide or oxirane groups. These epoxide groups serve as cross-linking points in the subsequent curing step, in which the uncured epoxy is reacted with a curing agent or hardener. Cross-linking is accomplished through the epoxide groups as well as through hydroxyl groups that may be present. Most conventional unmodified epoxy resins are produced from epichlorohydrin (chloropropylene oxide) [CH2OCHCH2Cl] and bisphenol A [(CH3)2C(C6H4OH)2]. The other types of epoxy resins are phenoxy resins, novolac resins, and cycloaliphatic resins. Epoxy resins are used as protective coatings, bonding adhesives, in building and construction, and for electrical , and many other uses.

Fluoropolymer
A family of thermoplastic resins analogous to polyethylene in which some of the hydrogen atoms attached to the carbon chain are replaced by fluorine or fluorinated alkyl groups. In some cases, other halogens such as chlorine are also part of the molecule. The most common commercial fluoropolymers are: FEP (fluorinated ethylene-propylene) from tetrafluoroethylene [C2F4] and hexa-fluoropropylene [C3F6]; PTFE (polytetra fluoroethylene) from the polymerization of tetrafluoroethylene and ethylene [C2H4]; PFA (perfluoroalkoxy) from tetrafluoroethylene and perfluoropropyl vinyl ether [C3H7C4OF5]; PCTFE (polychlorotrifluoro-ethylene) from chlorotrifluoro-ethylene monomer [C2F3CI]; CTFE-VDF (polychlorotrifluoroethylenevinylidene fluoride) from chlorotrifluoroethylene and vinylidene fluoride [C2H2F2]; E-CTFE (polyethylenechlorotrifluoroethylene) from chlorotrifluoroethylene and ethylene; PVDF (polyvinylidene fluoride) from vinylidene fluoride monomer; and PVF (polyvinyl fluoride) from vinyl fluoride monomer [C2H3F]. Typical applications for fluoropolymers are found in electrical/ electronic uses and pipe and chemical processing equipment.

Melamine-Formaldehyde
Thermosetting resins formed by the condensation reaction of formaldehyde [HCHO] and melamine [C3N3(NH2)3]. The chemistry is analogous to that of ureaformaldehyde except that the three amino groups of melamine provide more possibilities for cross-linking, are more highly reactive, and all six hydrogen atoms of melamine will react, forming the hexamethyl compound. Typical applications are found in bonding and adhesives, coatings, and consumer products.

Nitrile Resins
Thermoplastic resins composed of acrylonitrile [CH2CHCN] along with comonomer such as acrylates, methacrylates, butadiene [CH2CHCHCH2] and styrene [C6H5CHCH2]. Both straight copolymers and copolymers grafted onto elastomeric backbones are available. The unique property of these materials is outstanding resistance to passage of gases and water vapor, making them useful in packaging applications.

Nylon
A generic name for a family of long-chain polyamide engineering thermoplastics which have recurring amide groups [-CO-NH-] as an integral part of the main polymer chain. Nylons are synthesized from intermediates such as dicarboxylicacids, diamines, amino acids and lactams, and 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. Commercial nylons are as follows: nylon 4 (polypyrrolidone)-a polymer of 2-pyrrolidone [CH2CH2CH2C(O)NH]; nylon 6 (polycaprolactam)-made by the polycondensation of caprolactam [CH2(CH2)4NHCO]; nylon 6/6-made by condensing hexamethylenediamine [H2N(CH2)6NH2] with adipic acid [COOH(CH2)4COOH]; nylon 6/10-made by condensing hexamethylenediamine with sebacic acid[COOH(CH2)8COOH]; nylon 6/12-made from hexamethylenediamine and a 12-carbon dibasic acid; nylon 11-produced by polycondensation of the monomer 11-amino-undecanoic acid [NH2CH2(CH2)9COOH]; nylon 12-made by the polymerization of laurolactam [CH2(CH2]10CO)or cyclododecalactam, with 11 methylene units between the linking -NH-CO- groups in the polymer chain. Typical applications for nylons are found in automotive parts, electrical/electronic uses, and packaging.

Petroleum Resins
Thermoplastic resins obtained from a variable mixture unsaturated monomers recovered as byproduct from cracked and distilled petroleum streams. They also contain indene [C6H4CH2CHCH], which is copolymerized with a variety of other monomers including styrene [C6H5CHCH2], vinyl toluene [CH2CHC6H4CH3], and methyl indene [C6H3CH3CH2CHCH]. Typical applications are found in adhesives, printing inks, rubber compounding, and surface coatings.

Phenolic
These thermosetting resins are credited with being the first commercialized wholly synthetic polymer or plastic. The basic raw materials are formaldehyde [HCHO] and phenol [C6H5OH], although almost any reactive phenol or aldehyde can be used. The phenols used commercially are phenol, cresols [CH3C6H4OH], xylenols [(CH3)2C6H3OH], p-t-butylphenol [C4H9C6H4OH], p-phenylphenol [C6H5C6H4OH], bisphenols [(C6H4OH)2], and resorcinol [C6H4(OH)2]. The aldehydes used are formaldehyde and furfural [C4H3OCHO]. In the uncured and semi- cured condition, phenolic resins are used as adhesives, casting resins, potting compounds, and laminating resins. As molding powders, phenolic resins can found in electrical uses.

Polyamide-Imide
Engineering thermoplastic resins produced by the condensation reaction of trimellitic anhydride [OCC6H2C2O3] and various aromatic diamines. Typical applications are found in aerospace, automotive and heavy equipment industries.

Polyarylates
Engineering thermoplastic resins produced by interfacial polymerization of an aqueous solution of the disodium salt of bisphenol A [(CH3)2C(C6H4OH)2] with phthalic acid chlorides [C6H4(CO)2Cl2] in methylene chloride (CH2Cl2]. The major use of polyarylates is in outdoor lighting.

Polybutylene
Thermoplastic resins produced via stereospecific Ziegler-Natta polymerization of butene-1 monomer [CH2CHCH2CH3]. Typical applications are found in pipe and packaging film.

Polycarbonate
Engineering thermoplastic resins produced by (1) phosgenation of dihydric phenols, usually bisphenol A [(CH3)2C(C6H4OH)2], (2) ester exchange between diaryl carbonates and dihydric phenols, usually between diphenyl carbonate [(C6H5O)2CO] and bisphenol A and (3) interfacial polycondensation of bisphenol A and phosgene[COCl2]. Typical applications are found in glazing, appliances, and electrical uses.

Polyethylene
A family of thermoplastic resins obtained by polymerizing the gas ethylene [C2H4]. 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 (i.e., over 6000) are the materials used in the plastics industry. Polymers with densities ranging from about .910 to .925 are called low density; those of densities from .926 to .940 are called medium density; and those from .941 to .965 and over are called high density. The low density types are polymerized at very high pressures and temperatures, and the high density types at relatively low temperatures and pressures. A relatively new type called linear low density polyethylene is manufactured through a variety of processes: gas phase, solution, slurry, or high pressure conversion. A high efficiency catalyst system aids in the polymerization of ethylene and allows for lower temperatures and pressures than those required in making conventional low density polyethylene. Copolymers of ethylene with vinyl acetate, ethyl acrylate, and acrylic acid are commercially important. Major polyethylene applications can be found in packaging, housewares, toys and communications equipment.

Polyimides
A family of thermoset and thermoplastic resins characterized by repeating imide linkages: There are four types of aromatic polyimides: (1) condensation products made by the reaction pyromellitic dianhydride (PMDA) [C6H2(C2O3)2] and aromatic diamines such as 4,4'-diaminodiphenyl ether [(C6H4NH2)2O]; (2) condensation products of 3,4,3',4'-benzophenone tetracarboxylic dianhydride (BTDA) [(C6H5)2CO(C2O3)2] and aromatic amines;(3) the reaction of BTDA and a diisocyanate such as 4,4'-methylene-bis(phenylisocyanate) [OCNC6H4CH2C6H4NCO]; and (4) a polyimide based on diaminophenylindane and a dicarboxylic anhydride such as carbonyldiphthalic anhydride [OC6H4(CO)2COC6H4(CO)2]. Thermoset polyimides are produced in condensation polymers that possess reactive terminal groups capable of subsequent cross-linking through an addition reaction. Typical applications for thermoplastic and thermosetting polyimides are transportation and electronics.

Polyphenylene Oxide, Modified
Engineering thermoplastic resins produced by the oxidative coupling of 2, 6-dimethylphenol [(CH3)2C6H3OH] (xylenol), then blended with impact polystyrene. Typical applications are found in electrical/electronic uses, business machine parts, appliances, and automotive parts.

Polyphenylene Sulfide
Engineering thermoplastic resins produced by the reaction of p-dichlorobenzene [C6H4CI2] with sodium sulfide [Na2S]. The major use for polyphenylene sulfide is in electrical/ electronic parts and automotive parts.

Polypropylene
Thermoplastic resins made by polymerizing propylene [CH3CHCH2] and in the case of copolymers with monomers, with suitable catalysts, generally aluminum alkyl and titanium tetrachloride mixed with solvents. The monomer unit in polypropylene is asymmetric and can assume two regular geometric arrangements: isotactic, with all methyl groups aligned on the same side of the chain, or syndiotactic, with the methyl groups alternating. All other forms, where this positioning is random, are called atactic. Commercial polypropylene contains 90-97% crystalline or isotactic PP with the remainder being atactic. Most processes remove excess atactic PP. This by-product is used in adhesives, caulks, and cablefilling compounds. Major applications of commercial PP are found in packaging, automotive, appliance and carpeting markets.

Polystyrene
High molecular weight thermoplastic resins produced generally by the free-radical polymerization of styrene monomer [C6H5CHCH2] which can be initiated by heating alone but more effectively by heating in the presence of free-radical initiator (such as benzoyl peroxide [(C6H5CO)2O2]. Typical processing techniques are modified mass polymerization or solution polymerization, suspension polymerization, and expandable beads. Major markets for polystyrene are in consumer and institutional products, electrical/electronic uses, and building/ construction.

Polyurethanes
A large family of polymers based on the reaction product of an organic isocyanate with compounds containing a hydroxyl group. The commonly used isocyanates are toluene diisocyanate (TDI) [CH3C6H3(NCO)2], methylene diphenyl isocyanate (MDI) [OCNC6H4CH2C6H4NCO], and polymeric isocyanates (PMDI), obtained by the phosgenation of polyamines derived from the condensation of aniline [C6H5NH2] with formaldehyde (HCHO]. Polyols (with hydroxyl groups) are macroglycols which are either polyester or polyether based. Polyurethane elastomers and resins take the form of liquid castings systems thermoplastic elastomers and resins, microcellular products, and millible gums. Typical applications are found in the automotive industry. Polyurethane foams are widely used in transportation, furniture, and construction markets.

Polyvinyl Acetate (PVAc) & Other Vinyls
Polyvinyl acetate is a thermoplastic resin produced by the polymerization of vinyl acetate monomer [CH3COOCHCH2] in water producing an emulsion with a solids content of 50-55%. Most polyvinyl acetate emulsions contain co-monomers such as n-butyl acrylate, 2-ethyl hexyl acrylate, ethylene, dibutyl maleate and dibutyl fumarate. Polymerization of vinyl acetate with ethylene also can be used to produce solid vinyl acetate/ethylene copolymers with more than 50% vinyl acetate content. Polyvinyl alcohol (PVOH) is produced by methanolysis or hydrolysis of polyvinyl acetates. The reaction can be controlled to produce any degree of replacement of acetate groups. Co-polymers of replaced acetate groupings and other monomers such as ethylene and acrylate esters are commercially important. Polyvinyl butyral (PVB) is made by reacting PVOH with butyraldehyde [CH3(CH2)2CHO]. Polyvinyl formal is made by condensing formaldehyde [HCHO] in presence of PVOH or by the simultaneous hydrolysis and acetylization of PVAc. Polyvinylidene chloride is made by the polymerization of 1,1-dichloroethylene [CH2CCL2]. Typical applications for the above resins are found in adhesives, paints, coatings and finishes, and packaging.

Polyvinyl Chloride
Thermoplastic resins produced by the polymerization of the gas vinyl chloride [CH2CHCl]. Under pressure, vinyl chloride becomes liquefied and is polymerized by one of four basic processes: suspension, emulsion, bulk, or solution polymerization. The pure polymer is hard, brittle and difficult to process, but it becomes flexible when plasticizers are added. A special class of PVC resin of fine particle size, often called dispersion grade resin, can be dispersed in liquid plasticizers to form plastisols. The addition of a volatile diluent or a solvent to the plastisol produces an organosol. Copolymers with vinyl acetate, vinylidene chloride, and maleate and fumarate esters find commercial application. Major markets for PVC are in building/construction, packaging, consumer and institutional products, and electrical/electronic uses.

Styrene Acrylonitrile
Thermoplastic copolymers of styrene [C6H5CHCH2] and acrylonitrile [CH2CHCN]. SAN resins are random, amorphous copolymers produced by emulsion, suspension, or continuous mass polymerization. Typical uses include automobile instrument lenses and housewares.

Styrene Butadiene Latexes & Other Styrene Copolymers
Styrene butadiene latexes usually have a resin content of about 50%. The styrene/butadiene ratio varies from 54:46 to 80:20. Most are carboxylated by the use of such acids as maleic [HOOCCHCHCOO], fumaric [HOOCCHCHCOOH], acrylic [CH2CHCOOH], or methacrylic [CH2C(CH3)COOH]. Two types of styrene-maleic anhydride (SMA) [(COCH)2O] are available: SMA copolymers, with and without rubber impact modifier (e.g., DYLARK¨) and SMA terpolymer alloys (e.g., CADON¨). K-Resin¨ is a solid styrenebutadiene copolymer resin. Acrylic monomers are also used in conjunction with styrene (or styrene plus other monomers) to produce specialty resins. For example, there are transparent terpolymers of methyl methacrylate, butadiene, and styrene (MBS), and others of acrylonitrile, an acrylic monomer, and styrene (AAS). Ion-exchange resins or divinylbenzene-modified polystyrene are another variation. SB latexes are used in carpet backing and paper coatings. The other styrenics are used in paints, coatings, and floor polishes, plus many other uses.

Sulfone Polymers
A family of engineering thermoplastic resins characterized by the sulfone [SO2] group. Polysulfone is made by the reaction of the disodium salt of bisphenol A[(CH3)2C(C6H4OH)2] with 4,4'- dichlorodiphenyl sulfone 4,4'-DCDPS [(C6H4Cl)2SO2]. Polyethersulfone is made by the reaction of 4,4'-DCDPS with potassium hydroxide [KOH]. Polyphenylsulfone is similar to the other sulfone polymers. Typical applications for sulfone polymers are found in electrical/electronic uses and automotive parts.

Thermoplastic Polyester (Saturated)
A family of polyesters in which the polyester backbones are saturated and hence unreactive. The most common commercial types are: PET (polyethylene terephthalate) produced by polycondensation of ethylene glycol [CH2OHCH2OH] with either dimethyl terephthalate (DMT) [C6H4(COOCH3)2] or terephthalic acid (TPA) [C6H4(COOH)2]; and PBT (polybutylene terephthalate) produced by the reaction of DMT with 1,4 butanediol [HO(CH2)4OH]. Typical applications are found in packaging, automotive, electrical, and consumer markets.

Unsaturated Polyester
Thermosetting resins made by the condensation reaction between difunctional acids and glycols. The resulting polymer is then dissolved in styrene [C6H5CHCH2] or other vinyl unsaturated monomer. The structures of the acids and glycols used and their proportions, especially the ratio of the unsaturated versus the saturated acid, and the type and amount of monomer used, are all tailored for each resin to balance economy, processing characteristics, and performance properties. One common formulation is the reaction of maleic anhydride [(COCH)2O], phthalic anhydride [C6H4(CO)2O], and propylene glycol [CH3CHOHCH2OH]. Both dicyclopentadiene [C10H12] and isophthalic acid [C6H4(COOH)2] can be substituted for phthalic anhydride. Vinyl ester resins are linear reaction products of bisphenol A [(CH3)2C(C6H4OH)2] and epichlorohydrin [CH2OCHCH2Cl] that are terminated with an unsaturated acid such as methacrylic acid [CH2C(CH3)COOH]. Typical applications are found in transportation, appliances, electrical, and construction markets.
Urea-Formaldehyde

Formed by the condensation reaction of formaldehyde [HCHO] and urea [CO(NH2)2]. These thermoset resins are clear water-white syrups or white powered materials which can be dispersed in water to form colorless syrups. They cure at elevated temperatures with appropriate catalysts. Molding powders are made by adding fillers to the uncured syrups, forming a consistency suitable for compression and transfer molding. The liquid and dried resins find extensive uses in laminates and chemically resistant coatings. The molding compounds are formed into rigid electrical and decorative products.

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Sources: Chemical Economics Handbook, SRI International, Modern Plastics Encyclopedia, Whittington's Dictionary of Plastics, The Condensed Chemical Dictionary
society of plastics http://www.socplas.org/industry/defs.htm 8mar01