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HDPE: High Density Polyethylene LDPE

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HDPE: High Density Polyethylene LDPE Abbreviations: HDPE: high density polyethylene LDPE: low density polyethylene PET: polyethylene terephthalate PP: polypropylene PS: polystyrene PVA: polyvinyl alcohol PVC: polyvinyl chloride addition polymerization: a chemical reaction in which simple molecules are linked together to form long chain molecules. amorphous: non-crystalline polymer or non-crystalline areas in a polymer. Bakelite: a polymer produced by the condensation of phenol and formaldehyde. branched polymer: polymer having smaller chains attached to the polymer backbone. cellulose: a natmal polymer found in wood and other plant material. composite polymer: a filled or reinforced plastic. condensation polymer: one in which two or more molecules combine resulting in elimination of water or other simple molecules, with the process being repeated to form a long chain molecule. configuration: related chemical structme produced by the making and breaking ofprimary valence bonds. copolymer: a macromolecule consisting of more than one type of building unit. creep: cold flow of a polymer. cross-linking: occms when primary valence bonds are formed between separate polymer molecules. crystalline polymer: polymer with a regular order or pattern of molecular arrangement and a sharp melting point. dimer: a polymer containing two monomers. domains: sequences or regions in block copolymers. elastomer: a type of polymer that exhibits rubber-like qualities. Ekonol: a moldable, high temperatme polymer. end group: functional group at the end of a chain in polymers, e.g. carboxylic group. extrusion: a fabrication process in which a heat-softened polymer is forced continually by a screw through a die. filler: a relatively inert material used as the discontinuous phase of a polymer composite. free radical: A chemical component that contains a free electron which covalently bonds with a free electron on another molecule. homopolymer: a macromolecule consisting of only one type of building unit. initiation: the start of a chain reaction with a source such as free radicals, peroxides, etc. kevlar: a high strength polymer which can withstand high temperatures. linear: polymers made up of one long continuous chain, without any excess appendages or attachments. macromolecule: a polymer. 83 Polymers/The Material of Choice material: a substance useful for structural purposes. monomer: smallest repeating unit of a polymer. nylon: a polymer used commonly in the textiles industry. oligomer: a low molecular weight polymer in which the number ofrepeating units is approximately between two and ten. polyethylene: the most extensively produced polymer. polyester: a polymer with a COOR repeating unit. polymer: a high molecular weight macromolecule made up of multiple repeating units. polymerization: the chemical reaction in which high molecular mass molecules are formed from monomers. polystyrene: a polymer commonly used in packaging. propagation: the continuous successive chain extension in a polymer chain reaction. Tg: glass transition temperature below which a polymer is a hard glassy material. thermoplastic: a polymer which may be softened by heat and hardened by cooling in a reversible physical process. thermoset: a network polymer obtained by cross-linking a linear polymer to make it infusible or insoluble. T m: melting temperature. van der Waals forces: intermolecular attractions. viscosity: the resistance to flow as applied to a solution or a molten solid. vinyl chloride: the monomer used in PVC production. vulcanization: cross-linking with heat and sulfur to toughen a polymer. Source: Seymour and Carraher POLYMER CHEMISTRY Dekker 1993 84 .
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