双螺杆挤出机湿热法处理聚全氟乙丙烯不稳定端基

Unstable End Groups of FEP Disposed by Twin-screw Extruder Moist Heating

介绍了聚全氟乙丙烯(FEP)树脂不稳定端基的产生机理,一般处理方法及其优缺点。采用双螺杆挤出机湿热处理FEP粉料,分析了FEP树脂挤出造料前后端基数量。结果表明,—COOH数量减少最显著,平均减少55%;—CF=CF2基团平均减少9%,—COF基团基本不变。将脱羧与挤出造粒工艺作为一个操作单元,操作工艺简单、安全环保,设备投资少。

This paper introduced the unstable end groups of FEP resin production mechanism,the general treatment methods and their advantages and disadvantages.FEP powder was disposed by twin-screw extruder moist heating and the end group numbers before and after FEP resin extrusion pelleting were analyzed.The result showed that the number of —COOH reduced significant with an average of 55%;the number of —CF=CF2 reduced with an average of 9%;the number of —COF basically unchanged.Combing the decarboxylation and extruding pelletizing process as one operation unit could make the operation process simple,safety and environmental protection,equipment investment less.