稀土改性磨碎玻璃纤维对磨碎玻璃纤维/聚四氟乙烯复合材料性能的影响

摘要

采用三种表面改性剂,即硅烷偶联剂(PTMS)、含 PTMS 的稀土改性剂(PTMS-RES)和稀土改性剂(RES),对磨碎玻璃纤维表面处理,探讨了不同表面处理剂对磨碎玻璃纤维/聚四氟乙烯(MGF/PTFE)复合材料介电性能、热膨胀系数和热导率的影响.测试了 RES、未改性的磨碎玻璃纤维和 PTMS-RES 改性的 MGF 的FTIR 谱图,并采用 SEM对 MGF/PTFE复合材料的断口形貌进行分析.结果表明:与未经表面改性的 MGF/PTFE复合材料相比,经表面改性的 MGF/PTFE复合材料的介电性能、热膨胀系数、热导率都得到改善.由于RES特殊的电子层结构以及对阴离子有强吸引作用,RES改性效果比 PTMS更好.由于 RES与 PTMS共同的作用,PTMS-RES比 RES能更好地改善 MGF与 PTFE的界面,促进 MGF与 PTFE的界面粘结.%Three types of surface modifiers,i.e.phenyl trimethoxy silane modifier(PTMS),solution of rare earth modifier (RES)containing PTMS (PTMS-RES)and RES solution,were used for the surface treatment of the milled glass fiber.The effects of the different surface treatment conditions on the dielectric properties,coefficient of thermal expansion and heat conduction properties of milled glass fiber reinforced milled glass fiber/polytetrafluoro-ethylene (MGF/PTFE)composites were investigated in detail,and FTIR spectra of RES,unmodified and modified of MGF,and the fracture surfaces were analyzed by SEM.The experimental results show that the dielectric proper-ties,coefficient of thermal expansion and heat conduction properties of the MGF/PTFE composites filled with modi-fied milled glass fiber are improved,compared with that of the MGF/PTFE composite filled with unmodified milled glass fiber.The effect of milled glass fiber with RES is superior to PTMS due to the effects of rare earth specific electronic structure and has a strong attraction to the anion,PTMS-RES is superior to RES in improving the inter-face and promoting the interfacial adhesion between the milled glass fiber and PTFE due to the effects of rare earth with PTMS.