Thermal degradation of natural rubber/styrene butadiene rubber latex blends by thermogravimetric method

Thermal properties of natural rubber (NR)/styrene butadiene rubber (SBR) la tex blends made from latex blending have been investigated using thermograv imetric analysis. It was found that the initial degradation temperature of NR is lower than SBR, and on addition of SBR, the degradation temperature i s increased, indicating increased thermal stability of the blend. The main degradation products of NR contain isoprene and dipentene and that of SBR c ontains a large number of products like 4-vinyl cyclohexene, styrene, methy lbenzene, and so forth, in addition to that, the temperature at which 50% a nd 75% degradation of NR occurs is increased upon the addition of SBR. Vulc anization increased the thermal stability of NR/SBR blends slightly. The ac tivation energies for the degradation of the blends are higher than that of the homopolymers.