NOVEL CONJUGATED POLYMER CONTAINING AROMATIC RING AND SELENIUM IN BACKBONE - KINETICS OF THE ADDITION-REACTION AS THE MODEL FOR ADDITION POLYMERIZATION

The addition reaction mechanism of benzeneselenol to ethynylbenzene wa s studied as a model for the addition polymerization (so called polyad dition) of 1,4-benzenediselenol to 1,4-diethynylbenzene. The addition reaction occurred without an appreciable side reaction in the presence of AIBN and an adduct of the anti-Markownikoff's structure (O-Se-CH = CH-O) was quantitatively obtained. The addition reaction is very simi lar to the addition polymerization of 1,4-benzenediselenol to 1,4-diet hynylbenzene from the point of the geometrical structure of the polyme r chain. A kinetic study showed that a rate-determining step of the ad dition reaction was the addition step of the benzeneseleno radical to ethynylbenzene. The results were compared with those of the addition r eaction of benzenethiol to ethynylbenzene. By the competitive addition reaction, ethynylbenzene had 80 times higher reactivity than styrene toward benzeneselenol at 60-degrees-C in benzene.