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標題: China Perfluoroalkoxy Teflon-PFA news [打印本頁]
          

          
作者: zhufu740    時間: 2011-12-19 14:43
          
標題: 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    時間: 2016-2-21 10:12
          
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