EHTPB液体橡胶改性环氧树脂研究

Modification of Epoxy Resin with Epoxidized Hydroxyl Terminated Polybutadiene Liquid Rubber

用弱极性的低介电、低损耗及高绝缘电阻的环氧化端羟基聚丁二烯(EHTPB)液体橡胶改性环氧树脂(EP)。首先将EHTPB和EP反应生成预聚物,再用甲基六氢邻苯二甲酸酐固化,借助傅里叶红外光谱仪(FTIR)、核磁分析仪(1H-NMR)与扫描电子显微镜(SEM)等手段研究了EHTPB用量对改性EP固化物的性能及微观结构影响。结果表明:EHTPB端羟基同EP末端环氧基团间的化学反应强化了两者界面相容性,EHTPB均匀分散于EP中,在EHTPB较低用量下有效提高了EP固化物韧性,并且保留较高力学强度;相比未改性EP固化物,改性EP固化物的热稳定性、介电常数和介电损耗均下降,而击穿强度明显升高。

A weak polarity epoxidized hydroxyl terminated polybutadiene(EHTPB)liquid rubber with low dielectric and low loss and high insulation was employed to modify epoxy resin(EP).First,EHTPB was reacted with EP to form modified EP prepolymer,and then,the prepolymer was cured with anhydride curing.The effects of amount of EHTPB on the properties and morphology of cured EHTPB/EP were investigated by means of FTIR,1H-NMR,SEM,etc.The results show that the chemical reaction between EHTPB and EP enhances the interfacial compatibility,thus causing EHTPB even disperse in EP,and at low EHTPB concentration the modified EP exhibit improved toughness as well as high mechanical strength.Compared to unmodified cured EP products,the thermal stability,dielectric constant and dielectric loss of the modified cured EP products decrease,while the breakdown strength increases significantly.