高效空气过滤用PTFE膜材料的结构和性能

聚四氟乙烯(PTFE)膜高效空气过滤材料以其过滤效率高、初始阻力小和无硼释放等优点,在电子工业洁净室中得到了广泛的应用,然而目前尚缺乏PTFE膜与传统滤材结构及性能的系统对比研究。本文选取了两种商业应用的PTFE膜高效滤材,采用扫描电子显微镜、孔径分析仪、自动滤材测试仪等多种表征手段对材料的微观结构和过滤性能与超细玻璃纤维(简称玻纤)滤材进行了较为全面的对比研究,结果表明,PTFE膜本质上也是一种纤维类滤材,其纤维平均直径为60～85nm,远低于玻纤滤材的668.8nm;高效PTFE膜的过滤效率与玻纤滤材相当,且其初始阻力不及玻纤滤材的50%,但PTFE膜滤材的容尘性能不及玻纤滤材,更适合应用于有再生或预过滤装置的场所。

Structure and properties of PTFE membrane for high efficiency air filtration

PTFE membrane high-efficiency air filter material has been widely used in the clean room of the electronics industry because of its high filtration efficiency, low-resistance and boron-free release. However, there is still a lack of systematic comparative research on the structure and performance of PTFE membrane/conventional filter. In this paper, two commercial PTFE membrane high-efficiency filter materials were selected, and the microstructure and filtration properties of the materials were compared comprehensively with those of ultra-fine glass fiber filter materials by means of scanning electron microscopy, pore size analyzer, automatic filter material tester and other characterization methods. The results showed that PTFE membrane was essentially a kind of fiber filter material, and its average diameter was about 60—85nm, which was much lower than 668.8nm of fiberglass filter. The filtration efficiency of PTFE membrane was comparable to that of fiberglass filter, and its initial resistance was 50% lower than that of fiberglass filter. However, the dust-loading performance of PTFE membrane was inferior to that of fiberglass filter, which made the former more suitable for situation equipped with regeneration or pre-filtration devices.