Synthesis, structure, and property of well‐defined polymethylene‐based diblock copolymers by a combination of living polymerization of ylides and atom transfer radical polymerization

Abstract

Abstract A combination of living polymerization of ylides and atom transfer radical polymerization (ATRP) was used successfully in the design and synthesis of well‐defined polymethylene‐ b ‐poly(methyl methacrylate) (PM‐ b ‐PMMA) and polymethylene‐ b ‐poly( n ‐butyl acrylate) (PM‐ b ‐P n‐ BuA). Tripolymethylene borane were firstly synthesized by living polymerization of dimethylsulfoxonium methylides and then oxidated quantitatively through trimethylamine‐ N ‐oxide dihydrate to provide a series of low‐polydispersity hydroxyl‐terminated polymethylenes (PM‐OHs) with different molecular weight. Subsequently, such polymers were converted into polymethylene‐based macroinitiators (PM‐MIs, M n (GPC) = 1900–10,400 g/mol; M w / M n = 1.12–1.23) in ∼100% conversion. ATRPs of methyl methacrylate and n ‐butyl acrylate were successfully conducted using PM‐MI to produce well‐defined diblock copolymers of PM‐ b ‐PMMA and PM‐ b ‐P n‐ BuA, respectively. The GPC traces indicated the successful extension of PMMA and P n‐ BuA segment ( M n (GPC) of PM‐ b ‐PMMA = 3980–10,100 g/mol; M w / M n = 1.16–1.22; M n of PM‐ b ‐P n‐ BuA = 7400–9200 g/mol; M w / M n = 1.14–1.18). Atomic force microscopy (AFM) was used to characterize the structures of the precipitated PM‐ b ‐PMMA micelles, which were formed in toluene. The blend of LDPE/PMMA was prepared with PM‐ b ‐PMMA as compatibilizer. The scanning electron microscopy (SEM) results showed that the compatibilization of the LDPE/PMMA was improved greatly by the incorporation of PM‐ b ‐PMMA. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5671–5681, 2009