Natural rubber (NR) compounds were produced using an eco-friendly material, starch (St), as a filler. Natural rubber and starch (at different concentrations) were mixed with a coupling agent, resorcinol-formaldehyde. The natural rubber/starch mixture was coagulated in a CaCl2 solution using methanol and dried in a dry oven. The starch that dispersed in the natural rubber latex was measured by particle size analysis and field emission scanning electron microscopy. After co-coagulation and drying, the curing agent, vulcanization-accelerator and antioxidant were added to the mixture. The rubber was then vulcanized at the optimal temperature and time. The effect of the starch concentration on the curing characteristics and mechanical properties of the natural rubber/resorcinol-formaldehyde/starch compounds was investigated.

Metallocene catalysts, which were applicable to the polymerization process conditions of the Ziegler-Natta system were developed to precisely design the micromolecular structure and control the copolymerization reactivity. Research into polymerization using metallocene catalysts began with an identification of the structure of ferrocene by Wilkins and Fischer in 1952 and was developed further by Kaminsky in the 1980s. Copolymerization using metallocene catalysts, preparing polymers with narrow molecular weight distributions, high stereo-regularity and uniform comonomer incorporation are much easier than when a conventional Zeigler-Natta catalyst is used. Therefore, many studies have examined coordination polymerization using metallocene catalysts.A metallocene catalyst is called a single-site catalyst because it carries a single active site, which is unlike existing commercial Ziegler-Natta catalysts. For this reason, the polymers produced with metallocene catalysts exhibit high tacticity, have a narrow distribution of molecular weights and allow easy comonomer insertion 1-5 .On the other hand, previous studies focused mainly on copolymerization with little attention paid to terpolymerization [6][7][8][9][10][11][12][13][14][15] .In this study, terpolymers were prepared and the effects of the chain length of the comonomer on the catalytic activity, thermal and mechanical properties of the terpolymers were studied. Terpolymers composed of ethylene, high α-olefin and p-methyl styrene using a rac-Et(Ind)2ZrCl2 catalyst and cocatalyst system were synthesized. The terpolymers obtained were characterized by 1 H NMR and 13 C NMR spectroscopy. The catalytic activity, molecular weight, molecular weight distribution and compositions of the polymers were analyzed. The thermal properties of the polymers were investigated. The crystallinity of the terpolymers was determined by differential scanning calorimetry and wide-angle X-ray scattering. The catalytic activity increased to some degree with increasing chain length of the high a-olefin in the terpolymers. The crystallinity, mechanical and thermal properties decreased with increasing chain length of high α-olefins in the terpolymers.