四氟乙烯-全氟烷基乙烯基醚供聚物是由全氟烷基乙烯醚改性聚四氟乙烯,简称PFA。它改善了聚四氟乙烯加工困难的缺点,又使其性能和长期使用温度基本接收或保持聚四氟乙烯的水平。在PFA分子结构显示,它具有聚四氟乙烯相似的氟一碳架结构,但含有部分全氟烷基醚侧链。这种全氟烷氧基侧链较聚全氟乙丙烯(FEP)结构中的侧链长得多,并通过氧原子结合成特异的分子结构。因此,PFA具有明显的溶点,能够象聚全氟乙丙烯(FEP)一样熔融加工,但又保持了聚四氟乙烯的全部特点,故称“可熔性聚四氟乙烯”
Chemours 350 PFA Perfluoroalkoxy Copolymer
PFA
Chemours
产品说明:
Combines the processing ease of conventional thermoplastic resins with the excellent properties of PTFE. High chemical resistance, superior electrical properties, high service temperatures, superior high temperature creep resistance, excellent low temperature toughness, and exceptional flame resistance. Processed by conventional melt-extrusion and molding techniques. Resin Characteristics: Premium resin with enhanced ESCR. Lowest flow rate of this series. Uses: Films; chemical linings; transfer-molded articles; tubing.
Chemours was formed from former DuPont performance chemicals businesses, including DuPont Fluoroproducts, in 2015. This specific product was discontinued prior to the formation of Chemours.
20% Hydrochloric Acid Transmission, g/100sq in. | <0.02 | |
50% Sodium Hydroxide Transmission, g/100sq in. | <.02 | |
Acetic Acid Transmission, g/100sq in. | 0.41 | |
Acetone Transmission, g/100sq in. | 0.95 | |
Acetophenone Transmission, g/100sq in. | 0.5 | |
Benzene Transmission, g/100sq in. | 0.64 | |
Carbon Tetrachloride Transmission, g/100sq in. | 0.31 | |
Chemical/Solvent Resistance | Excellent | |
Ethyl Acetate Transmission, g/100sq in. | 0.76 | |
Folding Endurance, # cycles, .18-.20 mm | 500000 | |
Heat of Combustion J/g | 5300 | ASTM D240 |
Hexane Transmission, g/100sq in. | 0.56 | |
Piperidine Transmission, g/100sq in. | 0.04 | |
Red Fuming Nitric Acid Transmission, g/100sq in. | 7.5-1.4 | |
Salt Spray Resistance on aluminum, Hours | 1000 | |
Sulfuric Acid Transmission, g/100sq in. | 0.00001 | |
Water Transmission, g/100sq in. | 0.4 | |
Weather Resistance | 10 | Years unaffected in Florida Exposure |
在耐化学性和其它的特性中,PFA和耐化学性能优良,与聚四氟乙烯相同,PFA树脂不粘、不燃、低磨擦和耐环境应力开裂。
笔者在研究MIL-16878、MIL-22759、UL标准与VDE标准中所要求达到材料的性能指标中,PFA与PTFE基本相近,在这里不再详述。
PFA与PTFE性能比较,PFA与PTFE相比,除保持聚四氟乙烯的各种特性外,主要是易于加工,在熔点以上能熔融流动,可用挤出和模塑等方法加工。因而,凡要求具有聚四氟乙烯特性而用聚四氟乙烯难以加工者,都可以用PFA代替。