Automobile industry polyamides

Adipic acid is mainly used to produce nylon-6,6, a synthetic polyamide used in clothing, in the automobile industry, and in construction it also finds application in polyurethanes, plasticizers, and synthetic lubricants. Manufacture of nylon accounts for 89% of adipic acid consumption in North America, and 55-65% in Western Europe and Japan. 

There are recycling opportunities for other plastics beyond the few recognized by SPI RICs. The automobile industry, for instance, utilizes a series of engineering thermoplastics that have a built-in market if they can be recovered and reprocessed. These high value plastics include polyamides (Nylon 6, Nylon 6,6, etc.), polycarbonates (PC), acrylics (PMMA), styrenics (ABS), and blends (TPO, PC/PBT, PC/ ABS, etc.). Their higher value and demand allow recyclers the opportunity to practice more exotic recovery procedures and still have an economically viable product. 

Mica provides similar benefits in a wide range of thermoplastic and thermoset composites including polyolefins, polyamides and styrenics. It is also reported that surface coated mica further increases tensile strength, flexural strength and modulus, and heat deflection temperature. The automobile industry is the main user of mica-filled composites, either with polypropylene or nylon as polymer matrix. Up to 40% mica loadings are used, sometimes in association with calcium carbonate, to produce various injection... 

ETHYLENE We discussed ethylene production in an earlier boxed essay (Section 5 1) where it was pointed out that the output of the U S petrochemi cal industry exceeds 5 x 10 ° Ib/year Approximately 90% of this material is used for the preparation of four compounds (polyethylene ethylene oxide vinyl chloride and styrene) with polymerization to poly ethylene accounting for half the total Both vinyl chloride and styrene are polymerized to give poly(vinyl chloride) and polystyrene respectively (see Table 6 5) Ethylene oxide is a starting material for the preparation of ethylene glycol for use as an an tifreeze in automobile radiators and in the produc tion of polyester fibers (see the boxed essay Condensation Polymers Polyamides and Polyesters in Chapter 20)... 

Specialised polymers, which are mainly used in engineering applications in the automobile, aircraft and machinery industries, are known as engineering polymers. In this group, aliphatic polyamides are the most important and most widely used. A large number of aliphatic polyamides are obtained from vegetable oil-based products. Among these nylon 6,10, nylon 11, nylon 6,9 and poly(amido amine) are very important. One of the most important commercially used polymers, nylon 11, is obtained entirely from castor oU, whereas vegetable oil-derived components are only partly used to prepare other polymers. 

More than 60% of nylon is used in injection-molding applications. About 55% of this use is in the transportation industries, and most of this use is concerned with automobile production. Table 6 shows the split of applications for which nylon was used worldwide in 1998 (3). Descriptions of uses for polyamides, split into the principal application areas are given below. 

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