Polyethylene terephthalate finishes

Polymer coatings on stiffer substrates can be measured by time-resolved techniques (Sinton et al. 1989). Often in these cases it is not convenient to measure a direct reflection from an uncoated part of the substrate at more or less the same time, and anyway the substrate may not be flat, but this may not matter if it can be assumed that either the thickness or the longitudinal velocity of the coating does not vary. The time interval between the echoes from the top and bottom surfaces of the coating can then be used to determine the unknown quantity. An example of the kind of signal that can be obtained is shown in Fig. 10.5. The specimen was a coating of PET (polyethylene terephthalate) 15 m thick on a stone-finish rolled steel substrate. Although there is some overlap of the two echoes, there is no difficulty in... 

Fig. 10.5. Signals reflected from the top and bottom surfaces of a 15 ym thick coating of polyethylene terephthalate on a stone-finish rolled steel substrate, using a short pulse of centre frequency 230 MHz and half-power bandwidth 110 MHz z = +40 (with the top surface of the polymer as datum) (Sinton etal. 1989).

Silicon liquids (a solution of silicon-organic rubber in gasoline) and polyethylene terephthalate film are used to prevent sticking of finished articles to forms. It is worth noting that polyester film is most effective. With its application, RubCon articles are easily removed from the form and have a brilliant surface. 

Abstract The functionalization of synthetic polymers such as poly(ethylene terephthalate) to improve their hydrophilicity can be achieved biocatalytically using hydrolytic enzymes. A number of cutinases, lipases, and esterases active on polyethylene terephthalate have been identified and characterized. Enzymes from Fusarium solani, Thermomyces insolens, T. lanuginosus, Aspergillus oryzae, Pseudomonas mendocina, and Thermobifida fusca have been studied in detail. Thermostable biocatalysts hydrolyzing poly(ethylene terephthalate) are promising candidates for the further optimization of suitable biofunctionalization processes for textile finishing, technical, and biomedical applications. 

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. 

Polyethylene terephthalate polyester is the leading man-made fiber in production volume and owes its popularity to its versatility alone or as a blended fiber in textile structures. When the term "polyester" is used, it refers to this generic type. It is used extensively in woven and knitted apparel, home furnishings, and industrial appl ications. Modification of the molecular structure of the fiber through texturizing and or chemical finishing extends its usefulness in various applications. Polyester is expected to surpass cotton as the major commodity fiber in the future. 

The compatibilizer improves the mechanical properties of PE/starch, and addition of a plasticizer is actually detrimental to the finished products. Although PE is used here to demonstrate the results of this invention, results are practically the same with other combinations of polymer and compatibilizer as disclosed therein. Incorporation of compatibiHzer is easily accomplished by mechanical blending of the polymer, starch, and compatibilizer prior to extrusion. Typically, the compatibilizer is composed of the same polymer as the primary polymer itself. The polymer component of the compatibilizer may be selected from the group consisting of polyethylene, polypropylene, polystyrene, polybutylene, poly(styrene-ethyl-ene-butylene-stryrene), poly(ethylene terephthalate), polyvinyl fluoride, polyvinyl chloride, or derivatives thereof [6]. 

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