光响应性有机-无机杂化分子印迹聚合物的制备及表征

以4-硝基苯酚、 2,4-二氯苯氧乙酸和3-氯丙基三乙氧基硅烷为原料, 经氧化偶合、 酰化、 酯化反应合成了共价结合模板分子2,4-二氯苯氧乙酸(2,4-D)的光响应性含有机硅的偶氮苯功能单体, 通过溶胶-凝胶法制备了光响应性的有机-无机杂化分子印迹聚合物(OIHMIP). 研究了该分子印迹聚合物光响应性能、 对2,4-D的吸附性能和选择识别及光控释放与吸收能力, 用原子力显微镜对其形貌进行了表征. 结果表明, 制得的OIHMIP具有规则的球形, 粒径介于150～200 nm之间. OIHMIP对2,4-D具有良好的吸附和选择识别能力, 在365和440 nm的紫外-可见光交替照射下, 可控制2,4-D的释放与吸收.

Preparation and Characterization of Photoresponsive Organic-inorganic Hybrid Molecularly Imprinted Polymers

A photoresponsive functional azobenzene monomer containing silica was prepared by covalent imprinting for 2,4-dicholrophenoxyacetic acid(2,4-D) via oxidation-coupling reaction, acetylation and esterification reaction using commercially available p-nitrophenol, 2,4-dicholrophenoxyacetic acid and 3-chloropropyltriethoxysilane as the starting materials. Photoresponsive organic-inorganic hybrid molecular imprinted polymer(OIHMIP) for 2,4-D was prepared by sol-gel method. The photoresponsive properties, absorption abilities, selective recognition and photoregulated control the release and uptake of target molecule of OIHMIP were also studied. As characterized by atomic force microscope, the morphology of OIHMIP is sphere and the diameter of the spheres ranges in 150—200 nm. The experimental results show that OIHMIP has a high adsorption capacity and good selective recognition for 2,4-D, and reversible uptake and release of 2,4-D upon alternate irradiation at 365 and 440 nm, respectively.