Abstract
The cooperative molecular reorientation in methacrylate copolymer films comprised of hexamethylene spacer groups terminated with photoreactive hydrogen (H) bonded 4-oxycinnamic acid (CA) and 4-oxy-4’-methoxyphenylbenzoate (MBe) in their side chains was investigated by irradiating with linearly polarized ultraviolet light (LPUV) and subsequent annealing. Both CA and MBe side groups were miscible in all the copolymer composition, and axis-selective photoreaction of both side groups was observed. A thermally enhanced cooperative in-plane orientation of both side groups perpendicular to the polarization (E) of LPUV light was obtained when the exposed films were annealed in the liquid crystalline temperature range of the copolymers. The generated birefringence of the reoriented film was 0.12- 0.16 and the processing temperature was controlled between 85 and 165 °C by adjusting the copolymer composition.
