Synthesis and solution properties of cylinder brushes derivated by internal domain locking of poly(diblock macromonomer)s

Poly(diblock macromonomer)s (diblock copolymer brush) were synthesized by f ree-radical homopolymerizations of vinylbenzyl-terminated poly(alpha -methy lstyrene)-block-poly(2-vinylpyridine) (PMS-block-P2VP) diblock macromonomer . Dilute-solution properties of such diblock copolymer brushes were investi gated by static (SLS) and dynamic light scatterings (DLS) and small-angle X -ray scattering (SAXS). Effective diffusion coefficient D-eff for polymer b rushes with various aspect ratios showed the almost constant value in the r ange of polymer concentration 0-5 x 10(-3) g/cm(3). These results indicated that polymer brushes formed unimolecule structure even in good solvent suc h as benzene, it was speculated from angular dependence measurements that p olymer brushes with large aspect ratios took geometrical anisotropic confor mation such as cylinder. Subsequently, the cylinder brushes were derivated by crosslinking of internal P2VP domains of diblock copolymer brushes with 1,4-diiodobutane. These cylinder brushes also formed unimolecular structure in a dilute solution. However, semidilute solution properties of cylinder brush show a clear plateau region, which originates from entanglement effec t. This entanglement is caused by the thin thickness of PMS shell. (C) 2001 Published by Elsevier Science Ltd.