摘要
利用原子转移自由基聚合能对聚合物进行设计的优点,以水杨酸为原料,通过氯磺化制得5-氯磺酰基水杨酸,以此为引发剂,CuCl/2,2′联吡啶(Bpy)为催化体系,对苯乙烯(St)的聚合进行了研究,并且将制得的聚苯乙烯与铽离子配位.结果表明,聚合反应符合对单体浓度为一级的动力学关系;聚合物分子量随转化率呈线性增加;分子量分布较窄,Mw/Mn都在1.4以下;通过1H-NMR的端基分析,扩链反应都证明了聚合具有可控性;所有结果显示该聚合反应符合原子转移自由基聚合(ATRP)的特性.IR,UV-Vis和荧光光谱表明Tb(Ⅲ)与含水杨酸端基的聚苯乙烯配位成功,当用λ=305nm光激发,此配合物发射Tb(Ⅲ)的特征荧光.讨论了引发剂的浓度对聚合体系自由基活性特征的影响以及聚合物的分子量、配位条件对荧光强度的影响.
Fuctionalized polystyrene containing salicycylic acid end groups was prepared through atom transfer radical polymerization（ATRP） of styrene using 5-（chlorosulfonyl）salicycylic acid as initiator,which was obtained by chlorosulfonation of salicyic acid,CuCl as catalyst and Bpy as ligand,then coordinated with Tb（Ⅲ）.The polymerization displayed living characters as evidenced by a liner increase of molecular weight with conversation and a relatively narrow distribution（Mw/Mn less than 1.40）.PSt with an ω-chlorine atom in the chain end could be used as a macroinitiator to initiate MMA to form block copolymer（PSt-b-PMMA）.With [MMA]/[macroinitiator]/[CuCl]/[Bpy]=100∶1∶1∶1,the polymerization was carried out in solution（cyclohexanone） at 90℃.After 7 h,the molecular weight measured by GPC increased from 3590 to 11240,and the polydispersity index ranged from 1.23 to 1.50 with the conversion up to 78.1%;The end structure of PSt was analyzed by ^1H-NMR,and PSt can be used as a macroinitiator for block copolymerization,which also proved that the polymerization could be controlled.At the same time,because of the existence of phenolic hydroxyl and carboxylic groups,the subsequent functionalization led to novel functional materials.The polystyrene ligand was applied to prepare Tb（Ⅲ） complex.The polystyrene ligand and its complex were characterized through IR,UV-Vis and fluorescent spectra.The IR spectra of polystyrene ligand and its Tb（Ⅲ） complex showed that the band at 1683.4 cm^-1（ν（COOH）） disappeared,and the absorption band at 1210.8 cm^-1（ν（Ar—OH）） also disappeared.These results indicate that the —COOH and Ar—OH are coordinated with the Tb（Ⅲ） ion.From the UV-Vis spectrum when polystyrene ligand coordinated with Tb（Ⅲ） the absorption band at 300 nm became small,which was assigned to the charge transfers between central terbium atom and coordinated atoms.According to the fluorescent emission spectra when excited at 305 nm,the complex emitted charac
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2008年第9期838-842,共5页
Acta Polymerica Sinica
