THERMAL DEGRADATION OF NATURAL RUBBER/STYRENE BUTADIENE RUBBER LATEX BLENDS BY THERMOGRAVIMETRIC METHOD

Abstract

Abstract Thermal properties of natural rubber (NR)/styrene butadiene rubber (SBR) latex blends made from latex blending have been investigated using thermogravimetric analysis. It was found that the initial degradation temperature of NR is lower than SBR, and on addition of SBR, the degradation temperature is increased, indicating increased thermal stability of the blend. The main degradation products of NR contain isoprene and dipentene and that of SBR contains a large number of products like 4-vinyl cyclohexene, styrene, methylbenzene, and so forth. In addition to that, the temperature at which 50% and 75% degradation of NR occurs is increased upon the addition of SBR. Vulcanization increased the thermal stability of NR/SBR blends slightly. The activation energies for the degradation of the blends are higher than that of the homopolymers. Keywords: ThermogravimetryNatural rubber latexStyrene butadiene latex ACKNOWLEDGMENT One of the authors (JTV) is thankful to Council of Scientific and Industrial Research, New Delhi, for the Senior Research Fellowship.