SiO2表面改性对高填充SiO2/聚四氟乙烯复合薄膜性能的影响  

Effect of surface modification of SiO2 on properties of highly filled SiO2/polytetrafluoroethylene composite films

作　　者：周茜 张瑶 陈蓉[1] 沈佳斌[1] 郭少云[1] ZHOU Qian;ZHANG Yao;CHEN Rong;SHEN Jiabin;GUO Shaoyun(State Key Laboratory of Polymer Materials Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学高分子材料工程国家重点实验室,成都610065

出　　处：《复合材料学报》2020年第9期2144-2151,共8页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金创新研究群体科学基金(51721091)。

摘　　要：选用三种具有不同疏水官能团的硅烷偶联剂,即含苯基的偶联剂1(Ph-1)、含氟基的偶联剂2(F-2)和含环氧丙氧基的偶联剂3(GP-3)对SiO2进行表面改性,并采用空气辅助干法共混、冷压烧结并车削成膜的方法制备了SiO2填充量为35wt%、厚度为50μm的SiO2/聚四氟乙烯(PTFE)复合薄膜。改性后SiO2在PTFE中分散均匀。研究了不同含量F-2对SiO2/PTFE复合薄膜性能的影响,发现当含氟基的硅烷偶联剂F-2用量(与SiO2质量比)为0.3%时,SiO2/PTFE复合薄膜的针孔缺陷最少,拉伸强度由9.2 MPa提高至16.2 MPa;在10 GHz下,SiO2/PTFE复合薄膜的介电常数由2.475降低至2.416,介电损耗由2.66×10^-3降低至2.01×10^-3,SiO2/PTFE复合薄膜显示出优异的综合性能。Three silane coupling agents with different hydrophobic groups,namely phenyl-containing coupling agent 1(Ph-1),fluorine-containing coupling agent 2(F-2)and a glycidoxy-containing coupling agent 3(GP-3)were used to modify SiO2.The SiO2/polytetrafluoroethylene(PTFE)composite films with 35 wt%SiO2 and thickness of 50μm were prepared by air-assisted dry blending,cold-pressing,sintering and skiving techniques.The dispersion of SiO2 throughout the PTFE matrix is uniform after the modification.The effects of F-2 contents on the properties of SiO2/PTFE composite film were studied.The results show that when the content(mass ratio to SiO2)of the coupling agent is 0.3%,the pinhole defects of SiO2/PTFE composite film are rarely observed,and the tensile strength increases from 9.2 MPa to 16.2 MPa.Meanwhile,the dielectric constant decreases from 2.475 to 2.416 at 10 GHz,and the dielectric loss decreases from 2.66×10^-3 to 2.01×10^-3,exhibiting improved dielectric properties.

关 键 词：聚四氟乙烯 SIO2 硅烷偶联剂 介电性能 力学性能 

分 类 号：TB332[一般工业技术—材料科学与工程]