中国胶粘剂

采用机械热熔共混法制备了聚异丁烯(PIB)/甲基乙烯基硅橡胶(VMQ)共混物。通过差示扫描量热仪(DSC)、扫描电镜(SEM)以及旋转流变仪等表征手段,研究了不同配比PIB/VMQ共混物的结构及其加工性能。研究结果表明:PIB/VMQ共混物形成的是基本不相容的两相结构,但在相界面处存在分子链扩散。不同配比共混物的储能模量(G′)和损耗模量(G″)有明显的差别,表明相结构有明显区别;共混体系的G′和G″在低频区随剪切频率的增加而增加,在高频区呈现减缓甚至降低的趋势,其中PIB∶VMQ=70∶30体系的G′和G″最大;复数黏度随剪切频率的增加而降低,PIB∶VMQ=70∶30体系值最大,表明在VMQ含量为30份时能够形成互穿网络型双连续相结构。力学损耗因子(tanδ)表明:在低频区,VMQ的加入改善了材料的加工性能;在高频区,VMQ的加入使得材料的加工性能有所下降。

Polyisobutylene(PIB)/methyl vinyl silicone rubber(VMQ)blends were prepared by mechanical hot melt blending process. The structure and processing properties of different proportions of PIB/VMQ blends were studied by means of differential scanning calorimetry(DSC),scanning electron microscopy(SEM)and rotational rheometer. The research results showed that the PIB/VMQ blend formed a two-phase structure which was basically incompatible,but there was molecular chain diffusion at the phase interface. There were significant differences in storage modulus(G′)and loss modulus(G″)among different proportions of blends,indicating that the phase structure was obviously different. The G′ and G″ of the blend system increased with the increase of shear frequency in the low frequency region,and slowed down or even decreased in the high frequency region,in which the G′ and G″ of the blend system with PIB∶VMQ=70∶30 had the largest value. The complex viscosity decreased with the increase of shear frequency,and the system with PIB∶VMQ=70∶30 had the largest value,which indicated that the interpenetrating network type bi-continuous phase structure could be formed when the VMQ content was 30 phr.The mechanical loss factor(tanδ)indicated that the addition of VMQ improved the processing properties of the material in the low frequency region,while in the high frequency region,the addition of VMQ reduced the processing properties of the material.