| 초록 |
In this study, a practical and simple method for the synthesis of ABA-type olefin triblock copolymers, e.g., PE-b-poly(ethylene-co-propylene)-b-PE has been described. The performance of the so-called "coordinative chain transfer polymerization" (CCTP) by sequentially feeding ethylene and ethylene / propylene mixed gas, the Zn-bonded diblock copolymer(i.e., (PE-b-poly(ethylene-co-propylene)yl)2Zn). Treatment of the Zn-bound diblock copolymer with lauroyl peroxide (CH3(CH2)10C(O)O-OC(O)(CH2)10CH3) resulted in a C(sp3)-C(sp3) coupling reaction between the two diblock chains bound on the Zinc site and an ABA-type olefin triblock copolymer, PE-b-poly(ethylene-co-propylene)-b-PE, was formed. The occurrence of the coupling reaction was verified using a model compound, dioctyl zinc as CTA(Chain Transfer Agent) for CCTP. The ABA-type triblock copolymers exhibited thermoplastic elastomeric properties and significantly improved mechanical properties compared to diblock copolymer. |
