摘要
以α,ω-二羟基聚二甲基硅氧烷为基料,石墨烯、导热炭黑和氧化铝为导热填料,发泡微球为发泡剂,制得发泡硅橡胶材料。探讨了石墨烯、导热炭黑和氧化铝对发泡硅橡胶性能的影响,并采用扫描电子显微镜观察了发泡硅橡胶断面形貌。结果表明,随着石墨烯用量的减少和导热炭黑用量的升高,发泡硅橡胶的拉伸强度、密度和硬度均降低,热导率先升后降。当石墨烯用量为5份、导热炭黑用量为3份时发泡硅橡胶的热导率最高,为0. 119 W/(m·K)。球形氧化铝对硅橡胶的补强作用略低于非球形氧化铝,但两者对发泡硅橡胶的密度、硬度和阻燃性能的影响几乎相同。材料热导率随着球形氧化铝用量的减少和非球形氧化铝用量的增加先升后降。当球形氧化铝用量为25份、非球形氧化铝用量为30份时,材料热导率最高,为0. 101 W/(m·K)。片层石墨烯与球形导热炭黑相结合形成的"哑铃"结构增加了体系中的导热通路数量并提高了导热速率。非球形氧化铝以平面形式存在于泡孔壁内,并与较多的球形氧化铝接触,增加了体系中的导热通路数量。
The foamed silicone rubber was prepared by using α,ω-dihydroxypolydimethylsiloxane as the base material,graphene,thermally conductive carbon black and alumina as heat conducting fillers,and foamed microsphere as foaming agent. The effects of graphene,thermally conductive carbon black and alumina on the properties of foamed silicone rubber were studied. The cross-section morphology of foamed silicone rubber was observed by SEM. The results show that as the graphene amount decreases and thermally conductive carbon black amount increases, the tensile strength, density, and hardness of foamed silicone rubber decreases,and its thermal conductivity increases first and then decreases. When the amount of graphene and thermally conductive carbon black is 5 phr and 3 phr respectively,thermal conductivity of the foamed silicone rubber is the highest,with 0.119 W/( m·K) of thermal conductivity. The reinforcing effect of spherical alumina on silicone rubber is slightly lower than that of non-spherical alumina,but both have almost the same effects on the density,hardness and flame retardancy of foamed silicone rubber. With the decrease of spherical alumina and the increase of non-spherical alumina,the thermal conductivity of the material first increases and then decreases. When the spherical alumina is 25 phr and the non-spherical alumina is 30 phr,thermal conductivity of the material is the highest,which is 0.101 W/( m·K). The structure of dumbbell,which formed by the combination of lamellar graphene and spherical heat conducting carbon black,increases the number of heat conducting channels and the heat conducting rate. Non-spherical alumina exists in the cell wall in the form of plane,and contacts with more spherical alumina,which increases the number of heat conduction channels in the system.
作者
李苗
苏俊杰
曾幸荣
吴向荣
罗斌
LI Miao;SU Jun-jie;ZENG Xing-rong;WU Xiang-rong;LUO Bin(Zhaoqing Haoming Silicone Material Co.,Ltd.,Zhaoqing 526000,Guangdong;South China University of Technology,Guangzhou 510000,Guangdong)
出处
《有机硅材料》
CAS
2020年第1期43-46,共4页
Silicone Material
关键词
发泡硅橡胶
石墨烯
导电炭黑
氧化铝
热导率
foamed silicone rubber
graphene
conductive carbon black
alumina
thermal conductivity
