有机硅改性双酚A型环氧树脂研究

MODIFICATION OF BISPHENOL A EPOXY RESINS WITH CHLORIC ORGANIC SILICON

采用二氯二甲基硅烷 (DMS) ,或DMS与α ,ω 二氯聚二甲基硅氧烷 (DPS)的混合物来改性双酚A型环氧树脂 ,通过对固化物的冲击强度、拉伸强度、断裂伸长率和玻璃化转变温度 (Tg)的测定 ,探讨了改性方法、有机硅组成与含量等对材料性能的影响 .结果表明 ,用 5 7phr的DMS改性时 ,树脂固化物的冲击强度达2 0 2kJ m2 ,拉伸强度达 6 7 0MPa ,断裂伸长率达 11 2 9% ,Tg 达 16 8 0℃ ;分别比未改性时提高了 9 4kJ m2 ,2 1 1MPa ,5 4 %以及 32 6℃ .而用 0 7phrDMS +10phrDPS共同改性时 ,除Tg 和拉伸强度略有上升外 ,冲击强度达到了 31 6kJ m2 ,断裂伸长率达到 81 6 % ,分别比纯环氧提高了 2 0 8kJ m2 和 75 7% .

Bisphenol A epoxy resin was modified by dimethyldichlorosilane(DMS),or the mixture of DMS and α,ω dichloro polydimethylsiloxane(DPS). The connections between the properties of the modified systems and the composition and content of the organic silicons were investigated by measuring the impact strength, tensile strength, elongation,and glass transition termpereture( T g) of the cured materials. The results showed that, after modification with DMS of 5 7?phr, the materials exhibited improved impact strength (20 2?kJ/m 2), tensile strength (67 0?MPa), elongation (11 3%) and T g (168 0℃), which all were higher than those of the pure epoxy resin, they were 10 8?kJ/m 2, 45 9?MPa, 5 9% and 135 4℃,respectively. For materials modified by the mixture of 0 7?phr DMS and 10?phr DPS, the properties were further improved especially, the impact strength reached 31 6?kJ/m 2 and the elongation reached 81 6%. The fracture surfaces of the modified resins were investigated by scanning electronic microscopy(SEM). They showed typical characteristics of tough plastics, and for the one modified by 0 7?phr DMS+10?phr DPS many microparticles were observed which were supposed to be related with the significant increase in impact strength.