English Abstract
Branching Copolymer Synthesis from Divinylbenzene-containing Olefinic Terpolymer

Material Research Center of DENKI KAGAKU Kogyo K. K. Machida, Tokyo, Japan
Nippon Gomu Kyokaishi,(2009),82(9),382-388 Original Paper in Japanese

The ethylene (Et) - styrene (St) - divinylbenzene (DVB) terpolymer was synthesized from Et, St, and small amount of DVB using rac-isopropylidenebis (4,5-benzindenyl) zirconium dichloride/MAO coordination polymerization catalyst system. The terpolymer obtained highly keeps a pendant aromatic vinyl group from self cross-linking, which is considered to be a useful building block for the branching copolymer synthesis.
The branching copolymers are synthesized from the Et-St-DVB terpolymer and styrene using anionic poly-merization. The resulting copolymers showed uniformnano-scale phase separated structure corresponding to the main chain Et-St copolymer phase as soft segment and side chain polystyrene (PS) phase as hard segment. Mechanical strength and transparency increase with DVB content from 0.05 to 0.11 mol% of theEt-St-DVB terpolymers employed, with keeping good processability (MFR value). The mechanical properties are changed from thermoplastic elastomer to plastic by changing the weight ratio of the soft/hard segment, as well as the morphologies of the sea/islandstructure.

(Received on January 7, 2009)
(Accepted on June 5, 2009)

Single-site Polymerization Catalyst, Metallocene, Coordination Polymerization, Anionic Polymerization, Divinylbenzene, Branching Copolymer