Polypropylene Polystyrene

Over 70% of the total volume of thermoplastics is accounted for by the commodity resins polyethylene, polypropylene, polystyrene, and poly(vinyl chloride) (PVC) (1) (see Olefin polymers Styrene plastics Vinyl polymers). They are made in a variety of grades and because of their low cost are the first choice for a variety of appHcations. Next in performance and in cost are acryhcs, ceUulosics, and acrylonitrile—butadiene—styrene (ABS) terpolymers (see... 

Resins and plastics such as low-density polyethylene (LDPE), high-density polyethylene (HOPE), linear low-density polyethylene (LLDPE), polypropylene, polystyrene, and polyvinyl chloride (PVC) ... 

Optical Properties. The optical properties of a plastic which are important are refraction, transparency, gloss and light transfer. The reader is referred to BS 4618 1972 for precise details on these terms. Table 1.9 gives data on the optical properties of a selection of plastics. Some plastics may be optically clear (e.g. acrylic, cellulosics and ionomers) whereas others may be made transparent. These include epoxy, polycarbonate, polyethylene, polypropylene, polystyrene, polysulphone and PVC. 

Materials - LDPE, polypropylene, polystyrene, PVC, POM, acrylic, polycarbonate, nylon 66 and ABS. Note that the answers will give an indication of the flow ratios for these materials. The flow should be assumed to be non-isothermal. 

Polyethylene Low density Linear low density Medium density High density Polypropylene Polystyrene General purpose Impact... 

The most common backbone structure found in commercial polymers is the saturated carbon-carbon structure. Polymers with saturated carbon-carbon backbones, such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyacrylates, are produced using chain-growth polymerizations. The saturated carbon-carbon backbone of polyethylene with no side groups is a relatively flexible polymer chain. The glass transition temperature is low at -20°C for high-density polyethylene. Side groups on the carbon-carbon backbone influence thermal transitions, solubility, and other polymer properties. 

This comprehensive article supplies details of a new catalytic process for the degradation of municipal waste plastics in a glass reactor. The degradation of plastics was carried out at atmospheric pressure and 410 degrees C in batch and continuous feed operation. The waste plastics and simulated mixed plastics are composed of polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylonitrile butadiene styrene, and polyethylene terephthalate. In the study, the degradation rate and yield of fuel oil recovery promoted by the use of silica alumina catalysts are compared with the non-catalytic thermal degradation. 9 refs. lAPAN... 

Addition polymers, which are also known as chain growth polymers, make up the bulk of polymers that we encounter in everyday life. This class includes polyethylene, polypropylene, polystyrene, and polyvinyl chloride. Addition polymers are created by the sequential addition of monomers to an active site, as shown schematically in Fig. 1.7 for polyethylene. In this example, an unpaired electron, which forms the active site at the growing end of the chain, attacks the double bond of an adjacent ethylene monomer. The ethylene unit is added to the end of the chain and a free radical is regenerated. Under the right conditions, chain extension will proceed via hundreds of such steps until the supply of monomers is exhausted, the free radical is transferred to another chain, or the active site is quenched. The products of addition polymerization can have a wide range of molecular weights, the distribution of which depends on the relative rates of chain grcnvth, chain transfer, and chain termination. 

Polyacetal Polyacrylamide Polyacrylonitrile Polycarbonate Polyethylene Polyethylene oxide Polyethylene terephthalate Poly isobutyl methacrylate Poly methacrylic acid Polymethyl methacrylate Polymonochlorotrifluoro ethylene Polypropylene Polystyrene... 

Polypropylene //-Polystyrene //-Poly(4-methyl-1-pentene) //-Poly(4-methyl-1-pentene) //-Poly(vinylcyclohexane) 3/1 helix 3/1 helix 7/2 helix 4/1 helix 4/1 helix... 

Thermal stability. The presence of side chains, cross-linking, and benzene rings in the polymer s "backbone increase the melting temperatures. For example, a spectrum of polymers with increasing melting temperatures would be polyethylene, polypropylene, polystyrene, nylon, and polyimide. 

Polyacrylonitrile Poly(ethylene oxide) Poly(ethylene terephthalate) Polyisobutylene Poly(methyl methacrylate) Polypropylene Polystyrene... 

Hydroxyphenylbenzotriazoles have long been used as photostabilizers of polymers. For further details, see the 1990 review by Rabek photostabilizing mechanism of o-hydroxyphenylbenzotriazoles has been well investigated <87JPC1408). The absorption and fluorescence spectra of these photostabilizers have been the subjects of many publications (see Section 4.01.2.9). There are a great number of commercially available 2-(o-hydroxyphenyl)benzotriazoles. They have been widely used in the photostabilization of polypropylene, polystyrene, polyacrylates. 

Polyethylene Polypropylene Polystyrene Poly(vinyl chloride)... 

Property ABS Nylon0 PCb Polyester HDPE Polypropylene polystyrene Polyurethane ... 

The growth of these materials is reflected in the number of polymers which are being glass reinforced. These include polypropylene, polystyrene, styrene acrylonitrile, nylon, polyethylene, acrylonitrile-butadiene-styrene, modified polyphenylene oxide, polycarbonate, acetal, polysulfone, polyurethane, poly (vinyl chloride), and polyester. In addition, the reinforced thermoplastics available now include long-fiber compounds, short-fiber compounds, super concentrates for economy, a combination of long and short fibers, and blends of polymer and fibrous glass. 

Typical examples of thermosetting polymers are phenolic and urea-formaldehyde resins, unsaturated polyesters, and epoxy resins. Typical thermoplastics are polyethylene, polypropylene, polystyrene, and poly(vinyl chloride). The thermoplastic or thermosetting character of a polymer... 

Polymers are large molecules (macromolecules) that consist of one or two small molecules (monomers) joined to each other in long, often highly branched, chains in a process called polymerization. Both natural and synthetic polymers exist. Some examples of natural polymers are starch, cellulose, chitin (the material of which shells are made), nucleic acids, and proteins. Synthetic polymers, the subject of this chapter, include polyethylene, polypropylene, polystyrene, polyesters, polycarbonates, and polyurethanes. In their raw, unprocessed form, synthetic polymers are sometimes referred to as resins. Polymers are formed in two general ways by addition or by condensation. 

Thermoplastic A resin or plastic compound that can be repeatedly softened by heating and hardened by cooling. Examples of thermoplastics are acetal, acrylic, chlorinated polyether, fluorocarbons, polyamides (nylons), polycarbonate, polyethylene, polypropylene, polystyrene, some types of polyurethanes, and vinyl resins. 

Poly(phenylene sulphide) Polypropylene Polystyrene toughened with rubber Styrene-acrylonitrile... 

The mechanism of action of flame retardants in thermoplastic materials (polyethylene, polypropylene, polystyrene, cellulosics, PMMA, etc.) is unknown and is certainly quite complex. Broido (7) presented a good example in the difficulties of explaining how fire retardants work. He found that materials which were most effective in preventing flaming combustion of cellulose were also effective in causing sugar cubes to support flame ... 

Phosphorus Phosphate esters and others (halogenated and nonhalogenated) Polyurethane foams, polyesters, and thermoplastics such as flexible PVC, modified PPO, and cellulosics Also polyethylene, polypropylene, polystyrene, and ethylene/propylene copolymers Akzo Nobel, Albemarle, Amfine Chemical Corp., Amspec Chemical, Bayer, Ciba Specialty Chemical-Melapur, Clariant, Cytec, Daihachi Chemical Industry, Great Lakes, Italmatch Chemicals, Nitroil, Rhodia... 

A polymer is a large molecule composed of many smaller repeating units (the monomers) bonded together. Alkenes serve as monomers for some of the most common polymers, such as polyethylene, polypropylene, polystyrene, poly(vinyl chloride),... 

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