Engineering plastics polyethylene terephthalate

The Shodex GPC HFIP series is packed with a hexafluoroisopropanol (HFIP) solvent. Engineered plastics, such as polyamides (nylon) and polyethylene terephthalate, were analyzed previously at a high temperature of about 140°C. Using FIFIP as an eluent, such engineered plastics can be analyzed at ordinary temperatures (Table 6.4). 

Figures 6.18—6.20 show the chromatograms of engineered plastics such as polyamide (nylon) and polyethylene terephthalate at ordinary temperature.

Application Production of polymer-grade terephthalic acid (MTA). MTA is an excellent raw material to produce polyethylene tereph-thalate resin (PET), which is used for engineering plastics, packaging materials—like bottles and other food containers—as well as films. Also, integrated polyester producers use MTA to make various types of fibers. 

A.J.DeMaio (1991). Engineering High Performance Thermoset Resins from Polyethylene Terephthalate) Thermoplastics. Proceedings of the 46th Annual Conference of the Composites Institute of the Society of Plastics Institute, pp. 18C/1-18C/5. 

PP is most frequently compared with PE but other competitive materials are polystyrene and its derivatives, cellulose acetate (CA), cellulose acetate butyrate (CAB) and PVC. PP is used to replace engineering plastics, such as polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC) and ABS, etc., in kitchen appliances and domestic appliances. In non-plastics, PP faces competition from glass and metal. 

Polyethylene terephthalate (PET) is a versatile engineering plastic with excellent thermal and chemical resistance and mechanical performance. It is used extensively as fibers for apparel, in films for packaging, in bottles for beverages, and in engineering components. 

Certain Na and Ca salts of higher fatty acids (C28-C33), besides their acid scavenging property, influence the crystallization behaviour of polyolefins as well as of some engineering plastics such as PET (polyethylene terephthalate) and PA (polyamides). They exhibit certain nucleating effects, i.e. acceleration of crystalline kinetics and enhancement of mechanical properties of the finished article. 

Belofsky, H. Plastics Product design and process engineering. Hanser Publisher (1995). Berlinet, C., Ducruet, V., Brillouet, J. M., Reynes, M., and Brat, P. Evolution of aroma compounds from orange juice stored in polyethylene terephthalate (PET). FoodAdditives and Contaminants, 22(2), 185-195 (2005). 

Manipulation of individual polymers can result in forms which meet a remarkable range of end uses in a highly functional and economic way. Polyethylene terephthalate for example, a general-purpose polymer in many fiber, film and plastic uses, can be engineered to have very special properties. As fibers, they can be hollow, sheath core or have a variety of cross-sections and surfaces. Experimenting with this almost infinite set of variables has already led to ... 

The most important chain-growth polymers are polyolefins and other vinyl polymers. Examples of the former are polyethylene, and polypropylene, and examples of the latter are poly(vinyl chloride), polystyrene, poly(vinyl alcohol), polyacrylonitrile, and poly(methyl acrylates). The most common stepwise reactions are condensation polymerizations. Polyamides, such as nylon 6-6, which is poly(hexamethylene adipamide), and polyesters, such as poly(ethylene terephthalate), are the most important commercial condensation polymers. These polymers were originally developed for use in fiber manufacture because of their high melting points but are now used also as thermoplastics. Polycarbonate is an engineering plastic that is made from bisphenol A and phosgene by a stepwise reaction. 

In standard classification for vinyl plastics used in biomedical applications, a plasticizer is specified with prefix letter The letter is followed by a number from 1 to 14 which characterizes the type of plasticizer (e g., 1 - none, 2 - adipic acid derivative, 3 -azelaic, 4 - benzoic, 5 - citric, 6 - isophthalic, 7 - myristic, 8 - phosphoric, 9 - phthalic, 10 - sebacic, 11 - terephthalic, 12 - poly ether, 13 - polyethylene glycol, 14 - polyesters, 999 - other). The second letter specifies secondary plasticizer (e.g., A - none, B - alkyl epoxy stearates, C - epoxidized tall oil, D - epoxidized soybean oil, E - epoxidized linseed oil, F - epoxidized sunflower oil, Z - other). This classification is used to guide design engineers. Classification is not applicable to long-term implants. If there is a conflict between provisions of this standard and detailed specification for a particular device, the latter takes precedence. 

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