Synthesis and characterization of copolymer of 2,5-bis[(4-methoxyphenyl) oxycarbonyl]styrene and styrene with high molecular weight

The random copolymers of styrene and 2,5-bis[(4-methoxyphenyloxycarbonyl) styrene] (MPCS) with different copolymerization ratio were synthesized by conventional free radical polymerization. The copolymer having high molecular weight was experimentally elucidated using a combination of proton nuclear magnetic resonance spectroscopy and gel permeation chromatography. The liquid crystalline behavior of the copolymer was studied using differential scanning calorimetry, X-ray diffractometry and polarized optical microscopy. It was found that the liquid crystalline behavior was dependent on the content of styrene. Experimental results show that the copolymer could turn into a liquid crystalline phase at about 180??C when the content of styrene was less than 20%. The mechanical properties of the copolymer were also studied. Preliminary results indicate that the tensile strength decreases while the tensile modulus increases as the content of MPCS is increased. ? 2004 Springer-Verlag.SCI(E)EI中国科学引文数据库(CSCD)03289-2932