Synthesis of Amphiphilic Poly(methyl methacrylate- b-ethylene oxide) Copolymers from Monohydroxy Telechelic Poly(methyl methacrylate) as Macroinitiator MAHUA G. DHARA,* DURAIRAJ BASKARAN, SWAMINATHAN SIVARAM Division of Polymer Science and Engineering, National Chemical Laboratory, Pune 411008, India Received 22 March 2007; accepted 13 November 2007 DOI: 10.1002/pola.22548 Published online in Wiley InterScience (www.interscience.wiley.com). ABSTRACT: The synthesis of well-defined poly(methyl methacrylate)-block-poly(ethyl- ene oxide) (PMMA-b-PEO) dibock copolymer through anionic polymerization using monohydroxy telechelic PMMA as macroinitiator is described. Living anionic poly- merization 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 8C in the presence of LiClO 4 . The synthesized telechelic PMMAs had good control of molecular weight with narrow molecular weight distribution (MWD). The 1 H NMR and MALDI-TOF MS analysis confirmed quantitative functionalization of chain-ends. Block copolymerization of ethylene oxide was carried out using the ter- minal hydroxyl group of PMMA as initiator in the presence of potassium counter ion in THF at 35 8C. The PMMA-b-PEO diblock copolymers had moderate control of mo- lecular weight with narrow MWD. The 1 H 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 1 H NMR and dynamic light scattering. V V C 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2132–2144, 2008 Keywords: anionic polymerization; block copolymers; synthesis INTRODUCTION In recent years, syntheses of polymers bearing terminal functional groups draw significant in- terest. 1–4 One of the important utilities of termi- nal functional groups of a telechelic polymer is that they can be used in postpolymerization reactions such as crosslinking and chain-exten- sion. Depending on the nature of the functional groups, the postpolymerization can be followed through a different polymerization mechanism to form a variety of chain architectures like block, graft, and star-branched copolymers. Living anionic polymerization free from chain-transfer and termination reactions is ideal for introduction of chain-end functionality and it produces telechelic polymers with controlled mo- lecular weights with narrow molecular weight distribution (MWD). 5–8 Functional polymers can be prepared through termination of macroanions with suitable electrophiles, or by using func- tional group protected anionic-initiators to initi- ate the polymerization of suitable monomers. 9–13 A successful synthesis of telechelic polymer through anionic polymerization depends on the *Present address: GE India Technology Centre Pvt. Ltd., John F. Welch Technology Centre, Bangalore 560066, India. Correspondence to: D. Baskaran (E-mail: d.baskaran@ ncl.res.in) or S. Sivaram (E-mail: s.sivaram@ncl.res.in) Journal of Polymer Science: Part A: Polymer Chemistry, Vol. 46, 2132–2144 (2008) V V C 2008 Wiley Periodicals, Inc. 2132