Micellization of Graft Copolymers of Alkyl Methacrylates with alpha-Methyl-omega-hydroxypoly(oxyethylene)...

The solution properties of graft copolymers having a poly(methyl methacrylate-co-lauryl methacrylate) backbone and poly(oxyethylene) branches of different compositions were studied by static and dynamic light scattering methods in ethanol-water mixed solvents. The graft copolymers formed multimolecular aggregates in mixed solvents with water content higher than or equal to 10 vol%. The difference in solubility of lauryl and poly(oxyethylene) side chains of copolymers seems to be a dominant factor in determining their association behavior. The micelle formation is preferred in such solvents (water content >/=30 vol%) where the difference in solubilities of LAM and PEO side chains on graft copolymers is higher than a critical one. In conditions where there is a lower difference in solubilities of the side chains (water content 10-20 vol%), the random association of copolymers dominates. Copolymers were fully soluble in ethanol with low water content (1 vol%). The highest association number of micelles and consequently the lowest polydispersity were obtained with copolymers having the longest PEO side chains (Mw = 5000 g mol-1). Copyright 1998 Academic Press.