Functionalized copolymers. Methyl methacrylate-(4-hexyloxy-1-phenyloxycarbonyl)-1,4-phenylene ethylene copolymers: synthesis, monomer reactivity ratios, thermal stability and solubility

The synthesis and monomer reactivity ratios between methyl methacrylate and (4-hexyloxy-1-phenyloxycarbonyl)-1,4-phenylene-ethylene, a liquid-crystal monomer, were performed. Different starting monomer compositions were used to obtain copolymers with various compositions. Reactivity ratios r(1) and r(2) were estimated by the classical Fineman Ross and Kelen-Tudos linear pr ocedures and a non-linear method. These parameters were also estimated by u sing a computer program based on a non-linear minimization algorithm starti ng From the r(1) and r(2) values obtained by the above linear procedures. C opolymers were obtained by radical polymerization in THF solutions at 323 I t under vacuum. Linear representation of the polymerization data seems to i ndicate a random copolymerization with some tendency to blocks formation. T he thermal decomposition temperatures of the copolymers were determined by thermogravimetric analysis. The kinetic parameters associated with the deco mposition process. show that there are a decrease of the thermal stability of the copolymers relative to the homopolymers. (C) 2001 Elsevier Science L td. All rights reserved.