A new redox-activeliquid-crystalline copolymethacrylate with phenylazoanthraquinone side groups
Polimery 1999, No 1, 13
A copolymethacrylate (p2co3) was synthesized by radical solution polymerizationof methacrylate monomers II and III (Fig. 2); it was substituted via thehexamethylene spacer with 7 mole % of phenylazoanthraquinone and with 93 mole %of 4-methoxyphenylbenzoate. The composition of p2co3 was determined by 1H-NMR and confirmed by UV-VIS spectroscopy. The (number-average) Mn was 21,000 as determined by gel permeation chromatography; was 2.8 (Mw is the weight-average M). The number-average polymerization degree was 50. DSC measurements (20 K/min, 2nd heat run) gave a Ts of 42°C and revealed isotropization (high-temperature nematic-to-isotropic phasetransition) to occur at 110°C. Cyclic voltammetry (CV) disclosed that the copolymer could be reduced reversibly in a two-step redox process obeying the EE-mechanism. The multi-sweep CV experiments showed the polymer film to be endowed with a high electrochemical stability. To demonstrate its electrochemical properties, spectroelectro chemical studies of the copolymer are worth while.