Plastics in manufacturing

There are presently - 300 plasticizers in manufacture. Of these - 100 are of commercial importance. A Hst of some common commodity and speciahty plasticizers are given in Table 1. 

By directly dealing with a company which uses waste plastic in manufacturing... 

Recovered plastic can be marketed for reuse by directly dealing with a company which uses waste plastic in manufacturing, by directly dealing with a plastic pnx essor which will buy waste plastic and market the cleaned and decontaminated product, by listing the recovered waste plastic in a waste exchange for marketing or by marketing the... 

HOCHj CHjOH. Colourless, odourless, rather viscous hygroscopic liquid having a sweet taste, b.p. 197 C. Manufactured from ethylene chlorohydrin and NaHC03 solution, or by the hydration of ethylene oxide with dilute sulphuric acid or water under pressure at 195°C. Used in anti-freezes and coolants for engines (50 %) and in manufacture of polyester fibres (e.g. Terylene) and in the manufacture of various esters used as plasticizers. U.S. production 1979 1 900 000 tonnes. 

Alkanolamines with at least one NCH2CHOHCH,i grouping. Important materials include monoisopropanolamine NHX H CHOHCH, b.p. 159 C di-iso-propanolamine NH(CH CHOHCH b.p. 248 C triisopropanolamine NtCH -CHOHCHi). , b.p. 300 C. Manufactured from ammonia and propylene oxide. U ed, is weedkillers, as stabilizers for plastics, in detergents, alkanolaniine soaps for sweetening natural gas and in synthesis. 

Nylon A class of synthetic fibres and plastics, polyamides. Manufactured by condensation polymerization of ct, oj-aminomonocarboxylic acids or of aliphatic diamines with aliphatic dicarboxylic acids. Also rormed specifically, e.g. from caprolactam. The different Nylons are identified by reference to the carbon numbers of the diacid and diamine (e.g. Nylon 66 is from hexamethylene diamine and adipic acid). Thermoplastic materials with high m.p., insolubility, toughness, impact resistance, low friction. Used in monofilaments, textiles, cables, insulation and in packing materials. U.S. production 1983 11 megatonnes. 

The aromatic extracts have been used in the paint industry to partially replace linseed oil. They are still used for producing printer s ink. In addition, they are finding a variety of applications as plasticizers in the rubber industry or for the manufacture of plastics such as PVC. 

The principal worldwide manufacturers of nylon resins are given in Table 6. Total sales of nylon plastics in the United States and Canada in 1993 were 331,000 metric tons (37). West European sales were 352,000 t and Japanese sales 220,000 t (37). Figure 7 shows how sales in the United States have steadily increased since 1967 (38) and also how the price of nylon-6,6 has changed (39). The effect of the oil price rises, the boom of the mid-1980s, as well as the oil price reduction and the recession that followed are clearly evident. Table 7 shows the variation of price across different polyamide types. 

Chlorinated paraffins with the general molecular formula x 2x-y+2) have been manufactured on a commercial basis for over 50 years. The early products were based on paraffin wax feedstocks and were used as fine retardants and plasticizers in surface coatings and textile treatments and as extreme pressure—antiwear additives in lubricants. The development of chlorinated paraffins into new and emerging technologies was constrained principally because of the limitations of grades based on paraffin wax and the lack of suitable alternative feedstocks to meet the demands of the new potential markets. 

As already mentioned, much of the use for plastics just after World War II was as a cheap substitute for traditional materials, and in other cases the material was used for its novelty value. In many instances the result was detrimental to the industry and it required several years of painstaking work by the technical service departments of the major plastics materials manufacturers before confidence was regained in the use of plastics. Even today the public image of plastics is not entirely positive and the significant contribution of plastics to raising the standard of living and quality of life is not fully recognised. 

Plastics also find increasing use in vehicles for both water and air transport. Glass-fibre-reinforced plastic boats are widely used as a result of their economy in manufacture, ease of maintenance, lightness of weight and, for military purposes, antimagnetic characteristics. The non-corrosive nature of plastics also leads to their widespread use in boat fixtures and fittings. In aircraft, plastics are particularly useful on account of their low density. 

From the time that formaldehyde was first isolated by Butlerov in 1859 polymeric forms have been encountered by those handling the material. Nevertheless it is only since the late 1950s that polymers have been available with the requisite stability and toughness to make them useful plastics. In this period these materials (referred to by the manufacturers as acetal resins or polyacetals) have achieved rapid acceptance as engineering materials competitive not only with the nylons but also with metals and ceramics. 

The world production of plastics in 1995 is projected at 76 million metric tons (mT) with an annual growth rate (AGR) of 3.7%. The expected AGR of PBAs is 12% and that of composites 16%. In 1987, 21% of polymers were used in blends and 29% in composites and filled plastics [56]. If this trend continues, by 1995 all manufactured resins will be used in multiphase polymeric systems. Two factors moderating the tendency are ... 

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