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標(biāo)題: China Perfluoroalkoxy Teflon-PFA news [打印本頁(yè)]

作者: zhufu740    時(shí)間: 2011-12-19 14:43
標(biāo)題: China Perfluoroalkoxy Teflon-PFA news
pfa of pfa ball valve is very similar in composition to the fluoropolymers ptfe and fep (fluorinated ethylene-propylene). pfa and fep both share ptfe's useful properties of low coefficient of friction and non-reactivity, but are more easily formable. fep is softer than ptfe and melts at 260 °c; it is highly transparent and resistant to sunlight.
作者: fgh222    時(shí)間: 2016-2-21 10:12
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