Synthesis of (ABCB)n type ternary amphiphilic multiblock copolymer via poly(ethylene oxide) macro-chain transfer agent

A novel (ABCB)n type ternary amphiphilic multiblock copolymer was synthesized by stepwise insertion of monomers into the trithiocarbonate-embedded poly(ethylene oxide) (PEO) macro-chain transfer agent (PEO-CTA)n. (PEO-CTA)n was synthesized first by coupling of α,ω-dihydroxyl PEO with dicarboxylic trithiocarbonate, then styrene (St) and t-butyl acrylate (tBA) were inserted into the (PEO-CTA)n successively to yield (PEO-b-PS)n and (PEO-b-PS-b-PtBA-b-PS)n, respectively. After hydrolysis of the (PEO-b-PS-b-PtBA-b-PS)n, the final product (PEO-b-PS-b-PAA-b-PS)n was obtained.