多响应性甲氧基聚乙二醇丙烯酸酯-甲基丙烯酸共聚物的相变及荧光发射  

Phase Transition and Fluorescence Emission Characteristics of Multi-responsive Copolymer of Oligo(ethylene glycol)Methyl Ether Acrylate and Methylacrylic Acid

作　　者：董晓晶 曹红岩 姜绪宝[1] 孔祥正[1] 李树生[1] Xiao-jing Dong;Hong-yan Cao;Xu-bao Jiang;Xiang-zheng Kong;Shu-sheng Li(College of Chemistry and Chemical Engineering,University of Jinan,Jinan 250022;College of Chemistry and Chemical Engineering,Dezhou University,Dezhou 253023)

机构地区：[1]济南大学化学化工学院,济南250022 [2]德州学院化学化工学院,德州253023

出　　处：《高分子学报》2019年第12期1314-1321,共8页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21304038,51473066);山东省自然科学基金(基金号ZR2018BB049,ZR2018MB021);济南大学博士基金(基金号XBS1736)和济南大学科技计划(项目号XKY1824)资助项目

摘　　要：通过甲氧基聚乙二醇丙烯酸酯(OEGA)与甲基丙烯酸(MAA)自由基共聚制备了共聚物P(OEGA-MAA).通过氢核磁共振谱(~1H-NMR)及凝胶渗透色谱(GPC)对其结构进行了表征,对其相变及荧光性能进行测试,结果表明P(OEGA-MAA)对温度、pH及盐浓度具有响应性,并且在紫外光照射下发出肉眼可见的蓝色荧光.在此基础上,进一步研究了单体配比、pH及盐浓度等因素对其低临界溶解温度(LCST)的影响,表征了该聚合物受外界刺激时的荧光变化,揭示了其荧光性质与刺激响应时相分离过程的内在联系,提出了聚乙二醇氧原子间簇集诱导是该聚合物系的主要发光机理.本研究对了解PEG基刺激响应聚合物的荧光发射机理及拓展其实际应用均具有重要的意义.Multi-responsive polymers, with cluster-induced luminescence(CIE) featured by non-conjugated chromophores, have attracted great attention in recent years, and the relevant studies have been focused mainly on the polymers with aliphatic amines and carbonyl groups. Although the CIE behaviors of ethylene glycol-based polymers have been previously reported, studies that correlate their luminescent properties with their stimuliresponsiveness are rarely available. In this paper, P(OEGA-MAA), a copolymer responsive to temperature, pH and salt, was prepared by free radical copolymerization of oligo(ethylene glycol) methyl ether acrylate(OEGA)with methylacrylic acid(MAA) in ethanol. The structure of P(OEGA-MAA) was characterized by ~1 H-NMR and its molecular weight was determined by GPC. The evolution of light transmittance of the water solution of P(OEGA-MAA) with temperature was measured under different conditions and its fluorescence performance was characterized. The results show that P(OEGA-MAA) not only has responsive to temperature, pH and salt, but also emits visible blue fluorescence under UV. Effects of the polymer composition, pH and salt concentration on the lower critical solution temperature(LCST) and fluorescence properties are studied. And the relationship between fluorescence properties and phase transition process is also describled. As OEGA content decreased in the polymer, the LCST in its aqueous solution(2.0 mg/mL, pH=1) decreased, and the corresponding fluorescence intensity increased first with OEGA content up to 33 mol%(OEGA/MAA = 3.3/6.7, sample P7), where it reached a maximum, followed by a decrease with further decrease in OEGA. Effects of pH and NaCl concentration were also studied with P7 as an example. With increased pH in the aqueous solution(2.0 mg/mL) of P7, the LCST increased and the fluorescence intensity decreased;With the increase in NaCl concentration, the LCST decreased,while no obverious change was detected for the fluorescence intensity. Furthermore, when the polymer concentration

关 键 词：簇集诱导发光 聚乙二醇-甲基丙烯酸共聚物 多响应性聚合物 低临界溶解温度 荧光发射 

分 类 号：TQ317[化学工程—高聚物工业] O657.3[理学—分析化学]