Rubber substitute

Vinyl compounds. Vinyl chloride (prepared from acetylene and hydrogen chloride) 3 ields polyvinyl chloride (P.V.C.), which is employed as a rubber substitute and for other purposes. Vinyl acetate (from... 

The synthetic fiber industry as we know it began m 1928 when E I Du Pont de Nemours Company lured Professor Wallace H Carothers from Harvard University to direct their research department In a few years Carothers and his associates had pro duced nylon the first synthetic fiber and neoprene a rubber substitute Synthetic fibers and elastomers are both products of important contemporary industries with an economic influence far beyond anything imaginable m the middle 1920s... 

Methylpropene H2C = C(CH3)2 CH3 Polyisobutene is component of butyl rubber one of earliest syn thetic rubber substitutes... 

During the next few years PVC was steadily developed in the United States and in Germany. Both countries were producing the material commercially before World War II. In Great Britain, ICI in 1942 and the Distillers Company in 1943 also commenced pilot-plant production of PVC, a material then in demand as a rubber substitute for cable insulation. Paste-forming grades suitable for the production of leathercloth also became available soon afterwards. 

The latex of the Sapota achras yields a thermoplastic material, chicle, consisting of about 17.4% hydrocarbon, 40% acetone soluble resin and 35% occluded water. The hydrocarbon appears to contain both trans- and c/s-polyisoprene. Although originally introduced as gutta pereha and natural rubber substitutes, deresinated chicle has become important as the base for chewing gum. Like other polyisoprenes, it is meeting competition from synthetic polymers. 

An alternative chewing gum base is obtained from jelutong, a mixture of polyisoprene and resin obtained from latex of the Dyera costulata. This tree is found in many countries but Borneo is the principal commercial source. At one time jelutong was an important rubber substitute and 40000 tons were produeed in 1910. Production in recent years has been of the order of 5000 tons per annum, mainly for chewing gum. 

Faktis, n. factice (rubber substitute), faktischt a. real, actual, de facto. 

Chemical reactions are used to modify existing polymers, often for specialty applications. Although of considerable importance for plastics, very few polymer reactions (aside from crosslinking) are important for elastomers. Chlorination and bromination of Butyl rubber to the extent of about one halogen atom per isoprene unit yields elastomers which are more easily crosslinked than Butyl rubber. Substitution occurs with rearrangement to yield an allylic halide structure... 

Figure 4. Time domain trace resulting from the mechanical disbonding of a chlorinated rubber substitute.

Methylpropene H2C=C(CH3)2 ch3 Polyisobutene is component of "butyl rubber," one of earliest synthetic rubber substitutes. 

Synthetic rubber has been recently prepared, but it has not yet assumed importance as an industrial product. This must not be confused with rubber substitutes (principally jactis), which have been for long in common use, either alone or more frequently mixed with rubber. 

This is the name given to certain rubber substitutes prepared from fatty oils (linseed, cottonseed, colza, cameline, maize, soja bean, aiachis, castor, etc., or certain oxidised oils) and sulphur or sulphur chloride. Brown jactis is prepared by heating the oils with sulphur and usually forms compact, brown, and somewhat elastic masses. White factis is obtained by heating the oils with sulphur chloride and forms yellowish-white elastic masses, either light or compact or spongy. Both are insoluble in water or dilute acid and almost so in alcohol or acetone they dissolve, but only slowly, in ether, chloroform or carbon disulphide, and arc completely saponified by alcoholic potash. 

Europe soybean oils used in soaps glycerin sought for making explosives for Panama Canal project and printer s inks oil additionally used in rubber substitutes and linoleum flooring. 

By 1931 the first commercially successful rubber substitute, neoprene, was manufactured by DuPont. Among other rubber substitutes later developed in this country were butyl, Buna-N, and GR-S rubber made both from alcohol and from petroleum. Soon after the entry of the United States into World War II, our manufacture of synthetic rubber was stepped up to almost a millions tons a year. 

Sb sulfide, Ba(NOj)i or CaSi, by McNutt (Ref 56) LA with KClOj/S/Pb thiocyanate 40/ 10/50% by duPont (Ref 58) LA/natural, synth or rubber substitute by Snelling (Ref 63) LA/ 6a(N03)2/tetracene by Weale (Ref 62) LA/ diazoguanidine plcrate with or without tetryl by Imperial Chem Inds (Ref 67) LA/nitro-soguanidine by Olsen Seavey (Ref 61) LA/ nitratohypophosphite by Brun Burns (Ref 68) LA/ground glass by Hatch (Ref 70) LA/ various expl additives which lower flash pointy by Dynamit-AG (Ref 72) LA/Pb nitro sores-orcinate by Kerone Carroll (Ref 71) LA/... 

Free-radical polymerization of dienes. Rubber and rubber substitutes... 

Polymerization of dienes to form substitutes for rubber was the forerunner of the enormous present-day plastics industry. Polychloroprene (Neoprene, Duprene) was the first commercially successful rubber substitute in the United States. 

The properties of rubber substitutes—like those of other polymers—are determined, in part, by the nature of the substituent groups. Polychloroprene, for example, is... 

Through copolymerization there can be made materials with different properties than those of either homopolymer, and thus another dimension is added to the technology. Consider, for example, styrene. Polymerized alone, it gives a good electric insulator that is molded into parts for radios, television sets, and automobiles. Copolymerization with butadiene (30%) adds toughness with acrylonitrile (20-30%) increases resistance to impact and to hydrocarbons with maleic anhydride yields a material that, on hydrolysis, is water-soluble, and is used as a dispersant and sizing agent. The copolymer in which butadiene predominates (75% butadiene, 25% styrene) is an elastomer, and since World War II has been the principal rubber substitute manufactured in the United States. 

Emulsion polymerization is the basis of many industrial processes, and the production volume of latex technologies is continually expanding—a consequence of the many environmental, economic, health, and safety benefits the process has over solvent-based processes. A wide range of products are synthesized by emulsion polymerization, including commodity polymers, such as polystyrene, poly(acrylates), poly (methyl methacrylate), neoprene or poly(chloroprene), poly(tetrafluoroethylene), and styrene-butadiene rubber (SBR). The applications include manufacture of coatings, paints, adhesives, synthetic leather, paper coatings, wet suits, natural rubber substitutes, supports for latex-based antibody diagnostic kits, etc. ... 

When World War II resulted in the cutting off of the Allies supply of natural rubber, the polymer industry grew rapidly as chemists searched for rubber substitutes. Some of the most successful substitutes developed were gas- and od-resistant neoprene, now used to make hoses for gas pumps, and styrene-butadiene rubber (SBR), which is now used along with natural rubber to make most automobile tires. Although synthetic substitutes for rubber have many desirable properties, no one synthetic has aU the desirable properties of natural rubber. 

It is interesting indeed to look into the future with these recent developments as a background and see a great new chemical industry based on petroleum as a raw material. In fact, petroleum is a source from which many of the industrially important aliphatic compounds can be made and very probably at low cost. Some of the possibilities may be enumerated as formation of new solvents and plastics, new soaps and detergents, new flavors and perfumes, better rubber substitutes and softeners production of fuels with better properties, of lubricants having characteristics nearer the mythical ideal production of hydrogen and carbon monoxide for synthesis of compounds not possible of direct formation from hydrocarbons etc.2... 

The earliest synthetic polymers were synthetic rubbers. Before 1920 natural rubber was the only available elastomer, but constant attempts, with varying degrees of success, to develop commercial rubber substitutes had been made previously, especially by Engfish and German chemists, who competed with each other in the search. 

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