Good dispersion of hydrophilic nanoscale silica in rubber matrix and the effects on rubber nanocomposites

Using the industrial technologies of rubber latex irradiation, preparation of nanoscale silica (SiO₂) slurry, mixing irradiated rubber latex with SiO₂slurry, and the spray drying, we have prepared the ultrafine fully-vulcanized powder carboxyl styrene-butadiene rubber (UFPCSBR)/SiO ₂nanocompound powder, in which the SiO₂particles and UFPCSBR particles are isolated and stuck each other. When the UFPCSBR/SiO ₂nanocompound powder is mixed with crude rubber, the UFPCSBR particles are dispersed well in rubber matrix because of their good compatibility, then the SiO₂particles are also dispersed well in rubber matrix because of the carrier nature of the UFPCSBR particles during the mixing procedure, and the novel rubber/UFPCSBR/SiO₂nanocomposites are fabricated. Compared with the rubber composites prepared by mixing the crude rubber with the UFPCSBR powder and SiO₂powder one after the other, the novel UFPCSBR/SiO₂nanocompound modified rubber/UFPCSBR/SiO ₂nanocomposites have better abrasion resistance, higher tensile strength and tear strength, and lower heat build-up data. Noteworthily, the tanδtemperature curve of the novel rubber/UFPCSBR/SiO ₂nanocomposites has the second tanδ peak due to the newly generated boundary layer surrounding the SiO₂particles, increasing the tanδ values in the temperature range of 0-20°C, which is very important to the research of green tyre tread.