Poly ethylene terephthalate chemical containers

Statistical copolymerization of ethylene glycol and 1,4-butanediol with dimethyl ter-ephthalate results in products with improved crystallization and processing rates compared to poly(ethylene terephthalate). Polyarylates (trade names Ardel, Arylon, Durel), copolymers of bisphenol A with iso- and terephthalate units, combine the toughness, clarity, and proce-sibility of polycarbonate with the chemical and heat resistance of poly(ethylene terephthalate). The homopolymer containing only terephthalate units is crystalline, insoluble, sometimes infusible, and difficult to process. The more useful copolymers, containing both tere- and isophthalate units, are amorphous, clear, and easy to process. Polyarylates are used in automotive and appliance hardware and printed-circuit boards. Similar considerations in the copolymerization of iso- and terephthalates with 1,4-cyclohexanedimethanol or hexa-methylene diamine yield clear, amorphous, easy-to-process copolyesters or copolyamides,... 

The C-ls spectra of poly(ethylene terephthalate), poly(ethylene oxide), and anthraquinone are shown in Figure 7. All spectra were internally charge-referenced to an alkyl-like C-Is line at 284.0 eV. As shown in the figure, the oxygen-containing functional groups in these model compounds result in pronounced chemical shifts in the C-ls spectra. 

Most bioinert rigid polymers are commodity plastics developed for nonmedical applications. Due to their chemical stability and nontoxic nature, many commodity plastics have bwn used for implantable materials. This subsection on rigid polymers is separated into bioinert and bioerodable materials. Table 11.6 contains mechanical property data for bioineit polymers and is roughly ordered by elastic modulus. Polymers such as the nylons and poly(ethylene terephthalate) slowly degrade by hydrolysis of the polymer backbone. However, they are considered bioinert since a significant decrease in properties takes years. 

An obvious need exists for membranes with improved permeability and permselectivity. In addition to several earlier pieces of work contained in ref. Zg and Zh studies involving radiation-modified poly(vinyl alcohol) ordered polycarbonates " and cellulosic ion-exchange membranes have been reported. A variety of reports have appeared of the evaluation of existing polymers, such as polysulphone, in biomedical applications for which they have not previously been used, and of the synthesis of new polymers which may find use in the biomedical area. Examples include polyorganophosphazenes, biodegradable poly(ethyene oxide)-poly(ethylene terephthalate) copolymers, collagen copolymers, block copolymers of l,4-bis(acryloyl) piperazine-AW -dimethylethylene diamine and styrene, and >olymers derived fi om a miscellany of heterocyclic monomers. Information on chemically modified polymers designed for biomedical use is also contained in Chapter 16 of this Volume. 

Polyesters, poly(butylene succinate adipate) (PBSA), pofy(butylene succinate) (PBS), poly(ethylene succinate) (PES), pofy(butylene succinate)/poly(capiolactone) blend and poly(butylene adipate terephthalate) (PBAT) were evaluated about their enzymatic degradation by lipases and chemical degradation in sodium hydroxide solution [81]. In enzymatic degradation, PBSA was the most degradable by lipase PS from Pseudomonas sp. on the other hand PBAT containing aromatic ring was little degraded by 11 kinds of lipases. 

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