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首页> 外文期刊>journal of applied polymer science >The thermal decomposition of poly(vinylidene chloride) in the solid state
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The thermal decomposition of poly(vinylidene chloride) in the solid state

机译:聚偏二氯乙烯在固态下的热分解

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AbstractThe rate of decomposition of PVDC is sensitive to differences in the method of preparation of the polymer. Polymers prepared by mass polymerization of very pure monomer were most stable. Emulsion polymerized PVDC degraded the fastest. The activation energy for the latter was 34.4 kcal/mole. Over the range of 130°–190°C, the rate of decomposition increases with reaction time to ∼10 HCl evolved. Beyond this point, the reaction follows first‐order kinetics. The first‐order rate is independent of molecular weight. Lamellar crystals of PVDC degrade at a higher rate than “as polymerized” powders. This may be due in part to annealing of the crystals in the degradation temperature range; but it also results from a sensitization of the polymer to thermal degradation from exposure to the polar solvents used for recrystallization. A mechanism is proposed to account for these
机译:摘要PVDC的分解速率对聚合物制备方法的差异很敏感。通过非常纯的单体大规模聚合制备的聚合物最稳定。乳液聚合PVDC降解最快。后者的活化能为34.4千卡/摩尔。在130°–190°C范围内,分解速率随着反应时间的增加而增加,以释放出∼10%的HCl。超过这一点,反应遵循一级动力学。一阶速率与分子量无关。PVDC的层状晶体降解速率高于“聚合”粉末。这可能部分是由于晶体在降解温度范围内退火;但它也是由于聚合物暴露于用于重结晶的极性溶剂而对热降解敏感造成的。提出了一种机制来解释这些问题

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