CONCENTRATION FLUCTUATION DYNAMICS OF CONCENTRATED AQUEOUS HYDROPHOBICALLY-MODIFIED ACRYLIC COPOLYMER SOLUTIONS

The dynamics of concentration fluctuation in concentrated aqueous solu tions of a poly(hexaethylene glycol monomethacrylate-co-acrylic acid/a llyl glycidyl ether) copolymer were studied by means of the time-resol ved low angle laser light scattering (LALLS). Concentrated aqueous sol utions in the range 30-55% w/w showed a lower critical solution temper ature behaviour (LCST). A peak was observed in the scattered light pro file with time, I(q, t), when a temperature jump above the coexistence curve was performed. The peak shifted to lower q values with time in a logarithmic mode. Only at low q values and very short times did the solutions obeyed Cahn's linear spinodal decomposition kinetics, subseq uently slowing down.