ABSTRACT:Solution properties of regular amphiphilic comb-shaped polymers have been studied in water by means of fluorescence technique using pyrene as a probe, dynamic light scattering, 1 H NMR, and scanning force microscopy (SFM). They consist of a hydrophobic poly(p-alkylstyrene) as a main chain and hydrophilic poly(ethylene oxide) (PEO) chains as a graft chain. Two types of the comb-shaped polymers have been explored, which were prepared by micellar, organized homopolymerization of amphiphilic PEO macromonomers (1) (C 1 -EO n -(CH 2 ) m -S, with a p-alkylstyrene ((CH 2 ) m -S) end group, with m = 1 and 7, and a PEO chain with n = 18, 46, 115, and 469) and by copolymerization of C 1 -EO 18 -(CH 2 ) 7 -S with styrene in water, respectively. Partitioning, I 1 /I 3 , and excimer formation of pyrene were studied for their dilute aqueous solutions, and rationalized with the local concentration and structure of the comb-shaped polymers. Hydrophobic pyrene molecules were principally dissolved into the vicinity of the hydrophobic p-heptylstyrene main chain of the comb-shaped polymers. The nature of the hydrophobic main chain of poly(styrene-co-C 1 -EO 18 -(CH 2 ) 7 -S) was found to be essentially similar to that of a series of poly(C 1 -EO n -(CH 2 ) m -S). Direct observation of single macromolecule of poly(C 1 -EO 46 -(CH 2 ) 7 -S) by SFM revealed a high molecular weight, cylindrical brush-like conformation with ca. 12.8 nm in thickness. In contrast, small fine particles were observed for poly(styrene-co-C 1 -EO 18 -(CH 2 ) 7 -S), suggesting the formation of a unimolecular micelle in water.KEY WORDS Poly(ethylene oxide) Macromonomer / Amphiphilic Graft Copolymer / Combshaped Polymer / Scanning Force Microscopy / Branched Polymer / Pyrene / Fluorescence Spectroscopy / Unimolecular Micelle / Polymacromonomer / Micellization of amphiphilic polymers in a selective solvent has been of continuing interest over the past two decades. This is not only because of their biological relevance but also because of their usefulness for such industrial applications as paints, coatings, cosmetics, inks, and oil recovery.