Carbon Nanotube / Silica / Carbon Black / Solution-polymerized Styrene-butadiene Rubber Vulcanizate Performance

Carbon nanotubes-silica composite fillers give significantly better overall performances in comparison with the conventional fillers-silica and carbon nanotubes.In this paper, the HNO3 acid-treated MWNTs were first coated with inorganic silica by a sol-gel process and then grafted with y-methacryloxypropyltrimethoxysilane (KH570). After that, the MWNTs/SiO2/CB/SSBR composites were prepared through mechanical mixing on the basis of pretreatment of MWNTs/SiO2. The influence of silane functionalized MWNTs/SiO2 on the mechanical and thermal conductivity properties of MWNTs/SiO2/CB/SSBR compsites were investigated. The grafting of KH570 onto the MWNTs/SiO2 surface was confirmed by Fourier Transform Infrared Spectroscopy, Transmission electron microscopy, X-ray Diffraction and TG, et al.The results indicated that presence of MWNTs/SiO2 improves the curing process of the SSBR by shortening the time to optimum cure(t90) of cross-linked rubbers, which improves production efficiency. As the loading of the MWNTs/SiO2-KH570 increased, improved mechanical and thermal conductivity properties of MWNTs/SiO2/CB/SSBR compsites were observed. The storage modulus decreased and the glass transition temperatures increased when the content of MWNTs/SiO2-KH570 exceeded 5 phr due to agglomeration of MWNTs/SiO2-KH570. When the content of MWNTs/SiO2-KH570 was 10 phr, its tensile strength was improved by 28%,M100 and hardness were reinforced respectively by 54.3% and 14%,and the elongation at break reduced by 14.3%.