Hajime Shohi

Synthesis of end-functionalized polymers by living cationic polymerization of isobutyl vinyl ether with EtAlCl2

SummaryA series of end-functionalized polymers (4), carrying a hydroxyl, carboxyl, or primary amino terminal group Y, were obtained by living cationic polymerization of isobutyl vinyl ether. The initiating systems of choice consisted of EtAlCl2 and the trifluoroacetate [2; X-CH2CH2OCH(CH3)OOCCF3; X = OOCCH3, CH(COOC2H5)2, N(COOC(CH3)3)2] obtained from a vinyl ether with a protected functional pendant group. In the presence of 1,4-dioxane, the 2/EtAlCl2 systems invariably induced a well-defined living polymerization of isobutyl vinyl ether in n-hexane at 0 to +40°C to give polymers, the α-end group (X) of which was derived from the initiator 2. Subsequent de-protection of X of these polymers led to 4, all of which were shown to have a very narrow molecular weight distribution (¯MW/¯Mn = 1.07–1.18), a number-average molecular weight (¯Mn = 103-104) controllable by the monomer/2 molar feed ratio, and one terminal function Y per chain.

Tri-armed star polymers by living cationic polymerization

SummaryTri-armed amphiphilic block polymers (

Tri-armed star polymers by living cationic polymerization. 1. Trifunctional initiators for living polymerization of isobutyl vinyl ether

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Tri-armed star polymers by living cationic polymerization, 3. Synthesis of tri-armed star poly(p-methoxystyrene)†

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End-functionalized polymers by living cationic polymerization with EtAlCl2. 2. Synthesis of homo- and heterotelechelic poly(isobutyl vinyl ether)

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Process for preparing star compounds

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Tri-armed star polymers by living cationic polymerization: 2. Synthesis of tri-armed amphiphilic block copolymers of isobutyl and 2-hydroxyethyl vinyl ethers

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