No abstract

Xanthate is a class of non-toxic, rapid, and eco-friendly rubber vulcanization accelerator, but it is seldom used in the rubber industry because of its poor thermostability and ease of decomposition. To overcome these drawbacks, silica supported sodium isobutyl xanthate (silica-s-SIBX) was prepared by chemically bonding SIBX onto the silica surface. After loading, the initial degradation temperature (T0), maximum degradation temperature (Tp), and final decomposition temperature (Tf) of silica-s-SIBX were increased by 85.8, 118.9, and 146.9 °C, respectively. Meanwhile, silica-s-SIBX could not only improve the dispersion of fillers in the rubber but also enhance the interfacial interaction between silica and the rubber matrix. Therefore, it may offer new scientific and technological opportunities for preparation of green additives in the rubber industry.

Porous starch is modified by the addition of dodecenyl succinate anhydride (DDSA), to decrease the self-aggregation, and then blended with natural rubber (NR) latex to obtain the modified starch/NR composites. The composites are found to have improved properties compared with the corresponding pure NR. Results of a thermal analysis show that the thermal degradation reaction of modified starch/NR composites is a two-step reaction, with the initial (T 0 ) and the final (T f ) temperatures of main reaction being increased, and glass transition temperature (T g ) slightly reduced compared with the corresponding pure NR. The curves of elastic modulus (G 0 ) and loss factor (tanδ) versus the strain of unvulcanized rubber compounds are obtained using a rubber process analyzer. Dynamic mechanical thermal analysis shows that the rolling resistance of the composites is improved by the addition of modified starch.