由1,1'-双(4-氨基-3-巯基苯基)-4-叔丁基环己烷二盐酸盐(BAMPBCH.2HCl)与烯烃二元酸经过缩聚反应得到一类新型的含4-叔丁基环己基和烯烃共轭结构的双苯并噻唑类聚合物PBTsⅢ1,2.采用红外光谱(IR)、核磁共振氢谱(NMR)和元素分析(EA)表征聚合物的结构.4-叔丁基环己基的引入提高了此类聚合物的溶解性并保持了其较好的热稳定性,失重10%的温度在419℃以上.与聚苯撑苯并双噻唑(PBZT)相比,PBTsⅢ1,2的紫外吸收波长发生了蓝移;与聚2,2'-对苯撑-6,6'-(4-叔丁基)环己基双苯并噻唑(PBT)相比,PBTsⅢ1,2的紫外吸收波长发生了红移,它们的光学带隙分别为2.56和2.53 eV,表明大侧基和烯烃结构的引入扩大了苯并噻唑类聚合物光学带隙的可调范围.PBTsⅢ1,2的荧光发射波长较PBT发生了红移,表明大侧基的引入降低了固态时聚合物分子链的聚集程度.顺磁共振(EPR)的结果表明,PBTsⅢ1,2具有明显的顺磁共振信号,顺磁中心是其本身所固有的.
A new series of poly(bisbenzothiazole)s(PBTs Ⅲ1,2) containing 4-tert-butylcyclohexylidene and alkene units were prepared from 1,1-bis(4-amino-3-mercaptophenyl)-4-tert-butylcyclohexane dihydrochloride(BAMPBCH/52HCl) and alkene dicarboxylic acids by direct polycondensation.Their chemical structures were characterized by IR,1H NMR and elementary analysis.These polymers exhibited improved solubility due to the introduction of 4-tert-butylcyclohexene group into their structures.They also maintained good thermal stability.The decomposition temperatures at 10% mass loss of them were above 419 ℃.In comparison with poly[p-phenylene-6,6′-(4-tert-butylcyclohexene)bisbenzothiazole](PBT),the UV absorption spectra of PBTs Ⅲ1,2 showed that the λmax were red shifted.And compared with poly(p-phenylene benzobisthiazole)(PBZT),the λmax were blue shifted.The bandgaps of PBTs Ⅲ1,2 were 2.56 and 2.53 eV,which widened the optical bandgap range of the benzothiazole polymers.The emission wavelengths of PBTs Ⅲ1,2 were red shifted in contrast to PBT.The bulky pendant group decreased the aggregation degree of polymer chains.The results of EPR studies showed the intrinsic paramagnetic defects in PBTs Ⅲ1,2.