水溶液中P(AM-co-PEBA)聚合物对Tb3＋离子荧光增强作用

考察了Tb3＋离子在模板法合成的疏水缔合水溶性聚合物聚丙烯酰胺/4-(ω-丙烯酰氧乙氧基)苯甲酸(P(AM-co-PEBA))溶液中的荧光增强行为. 在溶液中P(AM-co-PEBA)通过羧基的络合作用及疏水缔合作用, 改变了 Tb3＋离子所处微环境, 降低了Tb3＋离子络合水的个数, 提高了Tb3＋离子荧光强度. 聚合物中PEBA含量增加或PEBA以微嵌段结构存在, 这一微环境效应得到增强. 另一方面, 聚合物P(AM-co-PEBA)分子内具有紫外光捕获基团, 可通过“天线效应”与Tb3＋离子进行能量传递, 进一步提高了Tb3＋离子的荧光强度.

Luminescence Enhancement of Tb3+Ion in Hydrophobically Associating P(AM-co-PEBA)Aqueous Solution

The fluorescence enhancement of Tb3＋ ion in the aqueous solution of acrylamide (AM) and 4-(ω-propenoyloxyethoxy)benzoic acid (PEBA) copolymers synthesized by a template copolymerization process was investigated. The complex of the carboxyl and the hydrophobic association changed the micro-environment of Tb3＋ ion, reduced the number of coordinated water molecules to Tb3＋ ion, so the fluorescence of Tb3＋ ion was enhanced. The content of PEBA was increased or the PEBA in the copolymer existed as micro-blocks, and the micro-environment effect was enhanced. Moreover the copolymer could transfer energy from the light-harvesting phenyl subunit to the Tb3＋ ion, which prominently enhanced the fluorescence intensity of Tb3＋ ion (antenna effect).