Polyphenyl sulfide polymer

Thermo-oxidation of polyphthalamides (PPA-1 and PPA-2) display the same regularities (kinetics of mass losses, oxygen absorption and release of the main volatile products, composition of volatile and heavy products relative to the polymer structure, oxidation inhibiting by adding PCA and transition metal compounds, etc.), which are described in detail for PAI, PPQ, polybenzoxazole (PBO), PEI, PI, PAIM, polyphenyl sulfide (PSP), PES and LCP. The degradation mechanism will now be discussed in more detail using PPA-1 and PPA-2 as examples (see Figure 7.5 and 7.6). 

SEC-viscometry and universal calibration has been widely used to determine the MWD of synthetic polymers, and selected applications are listed in Table 1. On-line viscometers have been successfully used at high temperatures Pang and Rudin (50) measured the MWD of polyolefins dissolved in 1,2,4-trichlorobenzene at 145°C, and Stacy (17) measured the MWD of polyphenyl sulfide in 1-chloronaphthalene at 220 °C. 

The major drawback of carbon-fiber thermoplastic composites is their low-temperature resistance.PH ] However, recently developed thermoplastic polymers have much higher temperature resistance and are being considered as matrices for continuous-fiber composites. These polymers include polyethersulfone (PES), polyetheretherketone (PEEK) and polyphenyl sulfide (PPS). 1 1 PEEK in particular has excellent potential since it is less brittle than the epoxies and provides a tougher composite (see Table 9.5 below). 

The simplest and the most widely-used method for the synthesis of sulfonated ACPs involves sulfonation of different classes of polymers, such as substituted poly-(l,4-phenylenes) [34,35], poly-(p-xylylene [36,37]), poly-(l,4-oxyphenylenes) [38-44], poly(ether ether ketones) (PEEK) [46- 59], polyary-lenefether sulfones) [3,60-74], poly(phenylene sulfides) [75], polyphenyl-quinoxalines [76-79], polybenzimidazoles [80], polyperyleneimides [81] and some other ACPs. 

The determination of traces of polar compounds is a very important application of adsorption capillary columns. For example, gas chromatographic analysis of hydrogen sulfide is often performed on polymer adsorbents (for example, Porapak Q, N or QS [39-44]). However, other adsorbents and stationary phases have been also used (Carbopack [45, 46], Triron X-305 [47- 8], Tenax GC [49], polyphenyl ether [48, 50] and various methyl silicone phases [51, 52]). Determination of hydrogen sulfide on WCOT columns has been performed with non-polar or medium polar silicone phases at sub-ambient temperatures [53-55]. 

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