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The synthesis of well‐defined poly(methyl methacrylate)‐block‐poly(ethylene oxide) (PMMA‐b‐PEO) dibock copolymer through anionic polymerization using monohydroxy telechelic PMMA as macroinitiator is described. Living anionic polymerization of methyl methacrylate was performed using initiators derived from the adduct of diphenylethylene and a suitable alkyllithium, either of which contains a hydroxyl group protected with tert‐butyldimethylsilyl moiety in tetrahydrofuran (THF) at −78 °C in the presence of LiClO4. The synthesized telechelic PMMAs had good control of molecular weight with narrow molecular weight distribution (MWD). The 1H NMR and MALDI‐TOF MS analysis confirmed quantitative functionalization of chain‐ends. Block copolymerization of ethylene oxide was carried out using the terminal hydroxyl group of PMMA as initiator in the presence of potassium counter ion in THF at 35 °C. The PMMA‐b‐PEO diblock copolymers had moderate control of molecular weight with narrow MWD. The 1H NMR results confirm the absence of trans‐esterification reaction of propagating PEO anions onto the ester pendants of PMMA. The micellation behavior of PMMA‐b‐PEO diblock copolymer was examined in water using 1H NMR and dynamic light scattering. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2132–2144, 2008

The kinetics of anionic polymerization of MMA has been studied at −78 °C in toluene‐THF (9:1 v/v) using 1,1′‐diphenylhexyl lithium as initiator in the presence of lithium perchlorate and lithium chloride as Lewis acid additives. The control of the polymerization is lost in the absence of additives as evident from the non‐linear first‐order time‐conversion plot and polymers with broad multimodal molecular weight distribution. The presence of LiClO4 and LiCl in 10:1 and 5:1 ratio, respectively, over the initiator brings about sufficient control, yielding polymers of narrow unimodal distribution throughout the polymerization. The reaction in the presence of the additives follows first‐order kinetics free of termination and transfer. Moreover, the order with respect to the active centers is found to be almost unity, which signifies a probable disaggregation of ion‐pairs to a single complexed propagating species.GPC elugrams at different conversions for MMA polymerization in the presence of LiClO4.magnified imageGPC elugrams at different conversions for MMA polymerization in the presence of LiClO4.

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