Elastomers, polymer classification

Synonyms Chlorosulfonated ethylene polymer Chlorosulfonated polyethylene CSM CSPE Ethene, homopolymer, chlorinated, chlorosulfonated Ethylene polymer, chlorosulfonated Ethylene resin, chlorosulfonated Polyethylene elastomer, chlorosulfonated Classification Olefin... 

The classification given in Table 1 is based on the process, ie, thermosetting or thermoplastic, by which polymers in general are formed into usehil articles and on the mechanical properties, ie, rigid, flexible, or mbbery, of the final product. AH commercial polymers used for molding, extmsion, etc, fit into one of these six classifications the thermoplastic elastomers are the newest. 

Chapters 10 to 29 consisted of reviews of plastics materials available according to a chemical classification, whilst Chapter 30 rather more loosely looked at plastics derived from natural sources. It will have been obvious to the reader that for a given application plastics materials from quite different chemical classes may be in competition and attempts have been made to show this in the text. There have, however, been developments in three, quite unrelated, areas where the author has considered it more useful to review the different polymers together, namely thermoplastic elastomers, biodegradable plastics and electrically conductive polymers. 

The broadest classification for plastics is the old thermoplastic and thermosetting . Examples of the former group are polyethylene, polystyrene, and poly-(methyl methacrylate) examples of the latter are urea-formaldehyde condensation polymers, powder coatings based on polyesters, epoxy resins, and vulcanized synthetic elastomers. 

Other Classification Criteria. Other levels of classification should be superimposed on the above. These include latex, suspension, and bulk type syntheses, all of which result in different properties of the final materials. Uses of plastic-forming and elastomer-forming monomers and crystalline and amorphous structures must be distinguished. The tacticity of the polymers is sometimes important. Of course, the ratio of both polymer masses dictates the overall morphology. Physical operations such as swelling, annealing, and orienting must be considered in any complete treatment. 

In the case of cellular rubber, the ASTM uses several classifications based on the method of manufacture [11,12]. Cellular rubber is a general term covering all cellular materials that have an elastomer as the polymer phase. Sponge rubber and expanded rubber are cellular rubbers produced by expanding bulk rubber stocks, and are open-cell and closed- cell, respectively. Latex foam rubber, which is also a cellular rubber, is produced by frothing a rubber latex or liquid rubber, gelling the frothed latex, and then vulcanizing it in the expanded state. 

Polymers can be classified in many ways, such as by source, method of synthesis, structural shape, thermal processing behavior, and end use of polymers. Some of these classifications have already been considered in earlier sections. Thus, polymers have been classified as natural and synthetic according to source, as condensation and addition (or step and chain) according to the method of synthesis or polymerization mechanism, and as linear, branched, and network according to the structural shape of polymer molecules. According to the thermal processing behavior, polymers are classified as thermoplastics and thermosets, while according to the end use it is convenient to classify polymers as plastics, fibers, and elastomers (Rudin, 1982). 

Further classification of polymers in the groups of additional polymers and condensation polymers has been on monomer composition, because this provides an orderly approach, whereas classification based on polymer uses, such as plastics, elastomers, fibers, coatings, etc. would result in too much overlap. For example, polyamides are used not only as synthetic fibers but also as thermoplastics molding compounds and polypropylene, which is used as a thermoplastic molding compound has also found uses as a fiber-forming material. 

EAPs can be broadly divided into two categories based on their method of actuation ionic and field-activated. Further subdivision based on their actuation mechanism and the type of material involved is also possible. Ionic polymer-metal composites, ionic gels, carbon nanotubes, and conductive polymers fall under the ionic classification. Ferroelectric polymers, polymer electrets, electrostrictive polymers, and dielectric elastomers fall under the electronic classification. 

A polymer normally used as a fiber may make a perfectly good plastic if no attempt is made to draw it into a filament. Similarly, a plastic, if used at a temperature above its glass transition and suitably cross-linked, may make a perfectly acceptable elastomer. In the following text, a brief account of some of the more common plastics, fibers, and elastomers is given. The classification is based essentially on their major technological application under standard working conditions. 

Synonyms Acrylonitrile/butadiene copolymer Acrylonitrile/butadiene rubber Acrylonitrile rubber 1,3-Butadiene, polymer with 2-propenenitrile NBR Nitrile/butadiene rubber Nitrile elastomer Nitrile rubber 2-Pro-penenitrile, polymer with 1,3-butadiene Classification Polymer... 

Synonyms Acetic acid, ethenyl ester, polymer with ethene Ethylene vinyl acetate Ethylene/vinyl acetate copolymer EVA EVA copolymer EVM Poly (ethylene-co-vinyl acetate) VAE VA/ethylene copolymer Vinyl acetate/ethylene copolymer Classification Elastomer... 

Classification Polymer synthetic elastomer Definition Unsaturated polymer of chloroprene Empirical (C4H5CI),... 

Synonyms Polysulfide elastomer Classification Synthetic polymer... 

Butyl-o-t-cyclohexyl acetate. See 2-t-Butylcyclohexyl acetate Butyl cyclohexyl phthalate CAS 84-64-0 EINECS/ELINCS 201-548-5 Synonyms 1,2-Benzenedicarboxylic acid, butyl cyclohexyl ester Classification Ester Empirical C18H24O4 Formula C4H9OOCC6H4COOC6H11 Properties Clear liq., very mild odor misc. with mostorg. soivs. m.w. 304.39 dens. 1.078 Precaution Combustible Uses Plasticizer for polymers, elastomers,... 

Synonyms Butanoic acid, 3,3-bis ((1,1-dimethylethyl) dioxy)-, ethyl ester Ethyl 3,3-bis (t-butylperoxy) butyrate Ethyl-3,3-di-(t-butylperoxy) butyrate Classification Org. peroxide Empirical C14H28O6 Properties M.w. 292.36 NFPA Health 2, Flammability 2, Reactivity 2 Uses Polymerization initiator initiator for curing elastomers and for polymer modification thermoplastic crosslinking agent Trade Name Synonyms Aztec EBU-40-G t[Aztec Peroxides] Aztec EBU-40-IC f[Aztec Peroxides]... 

Classification Polymer synthetic elastomer Definition Unsaturated polymer of chloroprene Empirical (C4HsCI)x Formula [CH2CH=CCICH2]x Properties As solid, latex, or flexible foam m.w. 100,000-300,000 dens. 1.23-1.35 brittle pt. -35 C softens. 80 C ref. index 1.5512 (20 C) high tens, str. resilient resistant to oils, oxygen, ozone, elec, current, abrasion... 

Classification Thermoplastic elastomer Definition Polymer of isoprene major component of natural rubber, also made synthetically avail, in range of std., oil-extended and carbon bik.-filled grades props, vary with catalysts used in mfg. (lithium, titanium)... 

Classification Thermoplastic elastomer Definition Polymer consistg. of hard segments embedded in a soft, elastomeric polyol phase exc. abrasion/impact resist. high str. wide working temp, range good hydrolytic stability two types polyether- or polyester-based Properties Solid... 

Classification Phosphite Empirical C27H47O3P Properties Wh. solid sol. in THF, toluene, cyclohexane, xylene m.w. 450 m.p. 90 C Uses Antioxidant for polyolefins, styrenics, engineering thermoplastics, PVC, elastomers, adhesives, food-grade polymers Regulatory FDA 21CFR 178.2010 Trade Name Synonyms Ultranox 641 t[GE Spec, http //www.ge. com/specialtychemicals]... 

CAS 13189-00-9 EINECS/ELINCS 236-144-8 Synonyms Methacrylic acid, zinc salt 2-Methylacrylic acid zinc salt 2-Propenoic acid, 2-methyl-, zinc salt ZDMA Zinc dimethacrylate Zinc 2-methyl-2-propenoate Classification Nonaromatic acid salt Empirical CsHio04Zn Properties M.w. 235.54 m.p. 229-232 C Toxicology Irritating to eyes, skin, respiratory system sensitizer TSCA listed Uses Coagent, scorch retarder, crosslinking agent for elastomer processing and cure polymer modifier... 

The macroscopic behavior of the polymer materials caused by the polymer architecture is the basis of the classification of polymers in thermoplastics, elastomers and thermosets. 

Polymer blends are a mixture of at least two polymers, their combination being supposed to lead to new materials with different properties. The classification of polymer blends into (1) immiscible polymer blends, (2) compatible polymer blends, and (3) miscible polymer blends is given by the thermodynamic properties of the resulting compound by means of the number of glass transition temperatures observed for the final product. To improve the compatibility between the blended polymers, some additives or fillers are used. To the same extent, rubber blends are mixtures of elastomers, which are usually combined to obtain an improved product, with properties derived from each individual component. 

Although there are numerous minor classification schemes for polymers, depending on how one wishes to categorize them, nearly all polymers can be placed in one of two major classifications—thermosetting materials (or thermosets) and thermoplastic materials. Likewise, foams, adhesives, embedding resins, elastomers, and so on, can be subdivided into thermoplastic and thermosetting classifications. 

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