基于不同间隔基的含三联苯甲壳型液晶聚乙炔的合成与性能研究

设计并合成一类含三联苯液晶基元的甲壳型液晶聚乙炔(-{HC=C-(CH2)mOOC-terpheyl(OC6H13)2]}n-,m=5,PHA5TP(OC6)2;m=9,PHA9TP( OC6)2),研究了聚合物的热稳定性、液晶性能和发光性能,考察了间隔基的长度对其性能的影响.结果表明,三联苯液晶基元赋予单体和聚合物...

SYNTHESIS AND PROPERTIES OF MESOGEN JACKETED LIQUID CRYSTALLINE POLYACETYLENE BEARING LATERAL TERPHENYL WITH DIFFERENT SPACERS

A group of novel mesogen jacketed mesomorphic polyacetylene containing terphenyl pendent groups with varying spacer lengths(—{HC-C—(CH2)mOOC-terpheyl-(OC6H13)2]}n—,where m=5,PHA5TP-(OC6)2;m=9,PHA9TP(OC6)2) are synthesized by polymerization using Rh(nbd)Cl]2 catalyst,and the structures and properties of the polymers are characterized and evaluated by IR,NMR,GPC,TGA,POM,DSC,XRD,UV and PL analyses.The effects of structural variations on the thermal,mesomorphic and luminescent properties were investigated by tuning the spacer length.The results show that the terphenyl mesogens endow the monomers and their polymers with good liquid crystalline behavior,and the monomers exhibit enantiotropic smectic C phases,while the polymers possess enantiotropic smectic A phases in the heating and cooling processes.The "jacket effect" from terphenyl mesogenic pendants at the waist position linked to the main chain contributes to the two polymers with high thermal decomposition temperature and excellent photoluminescence,which can lose almost no weight when they were heated above 370℃ and emit strong blue light at 410 nm when they were excited by the photons of 325 nm wavelength.In comparison with PHA5TP(OC6)2,the polymer with longer flexible spacer,PHA9TP(OC6)2,exhibits better liquid crystalline behavior,stronger UV light absorption and higher photoluminescence.