SYMMETRY-BREAKING IN PHASE-SEPARATION OF BINARY POLYMER MIXTURES INDUCED BY LINEARLY POLARIZED-LIGHT

Symmetry breaking of concentration fluctuations was found in a binary polymer mixture with one component photo-cross-linked by linearly pola rized light. As the reaction proceeds, the mixture undergoes phase sep aration, exhibiting lamellar morphologies with the direction closely p erpendicular to the polarization (E) of the exciting light. It was als o found that the phase separation is suppressed in the parallel direct ion and its kinetics strongly depends on the relative orientation with respect to the exciting polarization. Thus, these reacting mixtures p rovide a model system to study the directional phase separation driven by chemical reactions.[S1063-651X(98)51002-1].