"Living-like" cationic polymerization of isobutyl vinyl ether initiated bycarboxyl groups on carbon black surface/ethylaluminum dichloride system inthe presence of 1,4-dioxane

The effect of 1,4-dioxane as an added base on the cationic polymerization o f isobutyl vinyl ether (IBVE) initiated by carboxyl groups on carbon black surface/ethylaluminum dichloride (EtAlCl2) system was investigated. Althoug h the cationic polymerization of IBVE by carbon black/EtAlCl2 system the ab sence of 1,4-dioxane instaneously proceeded and the monomer conversion achi eved 100% within a minute. The molecular weight distribution (MWD) of polyI BVE obtained was very broad. On the contrary, the MWD of polyIBVE obtained was very narrow and narrower than that obtained from the carbon black/ZnCl2 initiating system by the addition of 1,4-dioxane. The number-average molec ular weight (Mn) of polyIBVE obtained was directly proportional to monomer conversion in the cationic polymerization.. However, the Mn of polyIBVE obt ained from the polymerization by the initiating system in the the presence of 1,4-dioxane was smaller than that of the calculated value, assuming that polyl(IBVE) chain forms per unit carboxyl group on carbon black surface. I t was concluded that carbon black/EtAlCl2 initiating systems in the presenc e of 1,4-dioxane has an ability to initiate "living-like" cationic polymeri zation of IBVE based on the above results. PoryIBVE was grafted onto a carb on black surface after quenching the above "living-like" cationic polymeriz ation systems with methanol.