溴甲酚绿-稀土配合物的热变色性能及变色机理

Thermochromic properties and mechanism of BCG-rare earth composite materials

以稀土金属离子(La3+、Ce3+和Nd3+等)为显色剂,溴甲酚绿为发色剂和配位剂,制备了一系列稀土配合物可逆热变色材料,测试其综合变色性能,讨论了显色剂种类及用量、溶剂用量对稀土配合物热变色性能的影响。FT-IR、UV-Vis和DSC测试结果表明,热变色机理可归结为分子间的电子得失,随着温度变化,溴甲酚绿的结构在内酯式和醌式之间转变,颜色随之改变。

A series of thermochromic composite materials composed of bromocresol green（BCG） and rare earth metal ions were prepared.The effects on thermochromism by the sort and ratio of delomorphic reagent and solvent were studied.Based on the identification of FT-IR,UV-Vis and DSC analysis,the thermochromic mechanism of composites were summarized for electron gain or loss among the molecules.At room temperature,quinonoid BCG is coordinated with rare earth metal ions.After warming,the complex was separated,lactone ring structure is recurring on BCG.Therewith,the color inversion can be realized with temperature variation.