pfa介绍 ：
氟塑料具有耐热、耐寒、耐候、耐药品、耐溶剂，绝缘性能及高频电性能优异．并具有不枯性、自润滑性、低磨擦系数等特点。聚四氟乙烯、全氟(乙烯—丙烯)共聚物(fep)完全是由碳原子和氟原子组成的，而聚偏氟乙烯(pvdf)、聚氟乙烯(pvf)分子中还含有氢原子但熔融碱金属、氟、三氟氯化烃对它们有不同程度的影响。pctfe、etfe、pvdf等在氟塑料中耐药品性稍差，但比其他塑料的耐腐蚀性还是好得多。3．电性能氟塑料的电性能尤其是高频电性能是其他材料难以匹敌的。ptfe、fep、pfa分子的极性很低，在很宽的温度、频率区间变化都很小、相对介电常数稳定、介电损耗很低，电绝缘性优异。其中pvdf还有特异的压电性和焦电性，可用来制造压电材料。4．机械性能氟塑料分子中含氢、氯原子增加则其拉伸强度也有所提高。ptfe和pctfe的脆化温度极低，显示出极好的低温性能。ptfe具有较低的摩擦系数和特异的自润滑性。但是ptfe又有自身磨耗大和冷流性等缺点。可采用填充各种填料以提高耐磨耗性，克服冷流性。不粘性氟塑料具有特异的不粘性。尤其象ptpe、fep、pfa等分子中氟含量高，表面接触角非常大，使氟塑料制品表面上的液体成球状。不易与树脂粘接，故常用它制造炊具表面不粘徐层。6耐侯性各品种的氟塑料都有优异的耐候性，即使在苛刻的温度下长期曝晒，其各种性能都没有变化.7．憎水性氟塑料的吸水率低，尤以ptfe为甚。可利用它的憎水性制造透气不透水的复合织物和其他装备。
perfluoroalkoxy
dupont fluoropolymers
产品说明：
for inventory control purposes product name may be followed byan x.
products labeled pfa te9725 and pfa te9725 x are e and allinformation in this document is applicable to both.
typical application
dupont™ teflon ® pfa te9725 is an ideal resin for applicationsinvolving compounding and compression molding, as well as extrudedtubing and other profiles for hose, electrical insulators, andsleeving; industrial film and products made from film; andinjection or blow-molded articles re superior electrical,chemical, and thermal properties. teflon ® pfa te9725 offers aslightly lower melt flow rate than teflon ® pfa te9724, ultimatelyproviding a higher degree of stress-crack resistance.
description
dupont™ teflon ® pfa te9725 is a general purpose fluoroplasticresin available as loosely compacted fluff. it is intended for usein special application processes in consultation with dupont.compared with other grades of teflon ® pfa, its most uni are a relatively low flow rate and properties that make itsuitable for a variety of processes and demanding end uses,especially compounding and compression molding. table 1 shows thetypical property data for teflon ® pfa te9725.
teflon ® pfa te9725 is used when traditional extrusion and moldingprocesses are required for producing products with the superiorproperties of a fluoroplastic resin. compared to otherthermoplastics, the high melt strength and thermal stability ofteflon ® pfa te9725 can be used to improve processing rates.compared with other thermoplastics, teflon ® pfa te9725 provides asuperior balance and level of end-use properties at high servicetemperatures. teflon ® pfa te9725 combines the processing ease ofconventional thermoplastics with many properties similar to thoseof polytetrafluoroethylene.
properly processed products made from neat teflon ® pfa te9725resin provide the superior properties characteristic offluoroplastic resins: chemical inertness, exceptional dielectricproperties, heat resistance, toughness and flexibility, lowcoefficient of friction, non-stick characteristics, negligiblemoisture absorption, low flammability, performance at temperatureextremes and excellent weather resistance.
in a flame situation, products of teflon ® pfa te9725 resistignition and do not promote flame spread. when ignited by flamefrom other sources, their contribution of heat is very small anddded at a slow rate with very little smoke.
teflon ® pfa te9725 meets the re of astm d3307, typeii
物性信息：
聚三氟氯乙烯则还含氯原子。氟塑料的优异性能是由碳原子与氟原子间的高结合能实现。聚四氟乙烯的主链骨架是碳原子，而周围完全由氟原子包围，故其各种性能高，而pfa、fep、etfe等品种由于侧基的影响，软化点低子ptfe，其他性能也有所变化。1．热性能氟塑料具有难燃性和优异的耐热性。ptfe和pfa的连续使用温度可达260℃，短期可在300℃下使用fep的使用温度要比它们低60℃。pctfe的可在120℃下使用。氟塑料如长期在高温下使用会引起结晶度变化，在制造设备衬里时尤须注意。2．耐药品性氟塑料具有卓越的耐药品性和耐溶剂性，尤其是ptfe、pfa、fep等，酸、碱、溶剂对它们均无浸蚀但熔融碱金属、氟、三氟氯化烃对它们有不同程度的影响。
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