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.

A range of polymers were synthesized using a rac-Et(Ind)2ZrCl2 catalyst and methylaluminoxane co-catalyst system. The polymers, homo-, co-and terpolymers were comprised of ethylene, 1-decene and p-methyl styrene. The structures and compositions of the polymers were examined by 13 C nuclear magnetic spectroscopy and 1 H nuclear magnetic spectroscopy. The catalytic activity, weight-averaged molecular weight, number-averaged molecular weight and molecular weight distribution of the polymers were characterized. The glass transition temperature, melting temperature, crystallization temperature, crystallinity, storage modulus, loss modulus and tan δ of the terpolymers according to the 1-decene feed molar concentration were also examined. compared with the thermal properties of the terpolymers, focusing on the comonomer effects of 1-decene. EXPERIMENTALAll manipulations were carried out in an inert nitrogen atmosphere. High-purity grade ethylene gas (Dae-myung Gas Co.) was used after passing it through an alumina/zeolite column. 1-Decene (Aldrich, 94 %), n-hexane (SAMCHUN, 99.5 %) and toluene (SAMCHUN, 99.5 %) were purified by heating them over sodium under reflux, using benzophenone as an indicator and stored in a dry box. A solution of rac-Et(Ind) 2 ZrCl 2 (Sigma Aldrich) in toluene was also prepared. p-methyl styrene (p-MS) was distilled under reduced pressure in the presence of CaH 2 after performing the standard purification procedure. The specimens for thermal and wide-angle X-ray scattering analyses were prepared by compression molding in a hot press. Typically, all the polymerization reactions were carried out in a 300 mL stainless steel autoclave with a mechanical stirrer.After saturating the autoclave with ethylene gas, polymerization was initiated by injecting the required amount of the monomers, catalyst solution and methylaluminoxane (MAO). After several minutes, the polymer solution was poured into a diluted HCl/EtOH solution. The resulting polymer was washed with EtOH (600 mL) and dried in vacuo.