摘要
以端基为氨基、羧基和羟基的表面改性氮化硼(BN)和未经表面修饰的BN纳米片为填料,通过原位聚合法制备了改性BN/聚酰亚胺(PI)复合材料,研究了氨基改性BN(BN-NH2)、羧基改性BN(BN-COOH)、羟基改性BN(BNOH)和BN对不同温度下复合材料导热特性的影响。结果表明:复合材料的热扩散系数随着BN-NH2质量分数的增加而增大,随BN-COOH和BN-OH质量分数的增加先增大后减小,且均在质量分数为2%时达到最大值。在200℃时,BN-NH2/PI的热扩散系数在填料质量分数为5%时达到最大值,BN-COOH/PI和BN-OH/PI则都在填料质量分数为2%时热扩散系数达到最大值,其中BN-COOH/PI获得最高的热扩散系数。因此,氨基表面改性BN有利于BN/PI复合材料在高填充量下获得更高的热扩散系数,而要获得最高的热扩散系数,羧基改性BN则是最佳选择。
Modified boron nitride(BN)/polyimide(PI) composites were prepared by in-situ polymerization using surface modified BN with terminal group of amino, carboxyl, and hydroxyl and unmodified BN nanosheets as fillers. The effects of BN modified by amino(BN-NH2), carboxyl(BN-COOH), and hydroxyl(BN-OH) and BN on the thermal conductivity of the composites at different temperatures were investigated. The results show that thermal diffusivity of the composite increases with the increase of the mass fraction of BN-NH2. With the increasing of BN-COOH and BN-OH, the thermal diffusivity of the composites increases at first and then decreases, reaches to the peak when the mass fraction of fillers is 2%.At 200 ℃, the thermal diffusivity of BN-NH2/PI reaches to the maximum when the mass fraction of fillers is 5%, while that of BN-COOH/PI and BN-OH/PI reaches to the maximum at when the mass fraction of fillers is 2%, and BN-COOH/PI shows the highest thermal diffusivity. Therefore, surface modification by amino is beneficial for BN/PI composites to obtain a higher thermal conductivity at high fillers content, while carboxyl modification is the best choice to obtain the highest thermal conductivity.
作者
白泽钊
杨柳青
冯阳
徐春萌
BAI Zezhao;YANG Liuqing;FENG Yang;XU Chunmeng(State Key Laboratory of Electrical Insulation and Power Equipment,Xi'an Jiaotong University,Xi'an 710049,China)
出处
《绝缘材料》
CAS
北大核心
2023年第2期63-67,共5页
Insulating Materials
关键词
氮化硼
聚酰亚胺
导热性能
表面改性
boron nitride
polyimide
thermal conductivity
surface modification
