Macromolecules, Vol.39, No.20, 6800-6810, 2006
Comparison of the thermotropic and solution behavior of six-arm star and comb poly[11-(4'-cyanophenyl-4''-phenoxy) undecyl acrylate]s
"Six-arm star" poly[11-(4'-cyanophenyl-4''-phenoxy) undecyl acrylate]s with 13-112 (gel permeation chromatography, GPC, relative to linear polystyrene) or 23-756 (GPC using a light scattering detector) repeat units were synthesized from the hexafunctional initiator, 1,2,3,4,5,6-hexa((4'-methyl(2''-bromopropionate)phenoxymethyl) benzene, by atom transfer radical polymerization of 11-(4'-cyanophenyl-4''-phenoxy)undecyl acrylate, followed by fractionation to narrow the polydispersity to 1.06-1.57. The absolute molecular weight, size, and shape of these polymers were characterized by light scattering in CH2Cl2, and their thermotropic behavior was analyzed by differential scanning calorimetry; both types of properties were compared to those of the other architectures, especially the corresponding comb poly[11-(4'-cyanophenyl-4''-phenoxy) undecyl acrylate] s with six branches. The solution and thermotropic behavior of the six-arm star and comb polymers are similar.