摘要
以类雌性激素双酚A为模板分子,选取4-乙烯基吡啶作为功能单体,在极性溶剂甲醇中,通过非共价键完成自组装过程,沉淀聚合制备对双酚A分子具有高度选择性识别和亲和力的分子印迹聚合物.采用紫外-可见光谱研究了双酚A和4-乙烯基吡啶的配合方式以及配位比,结果表明双酚A与4-乙烯基吡啶以配位比1∶2的方式,在极性溶剂中,无法以常用的氢键形成超分子配合物,却可以π-π堆积这种非共价键完成自组装过程.通过红外谱图,验证了沉淀聚合法制备的印迹聚合物可以完成双酚A的印迹和可逆分离.通过扫描电镜和等温吸附实验考察了分子印迹聚合物对模板分子的特异性识别和选择性吸附机理,印迹聚合物的特异性吸附容量为37.39μmol/g,印迹指数为4.31;对其结构类似物四溴双酚A和苯酚的分离因子分别为2.51和2.06,同时对莠去津,萘普生和槲皮素的分离因子分别为2.14,2.26和2.63,证实了分子印迹聚合物在极性溶剂中可以对双酚A分子进行很好的特异性识别,并且识别环境更接近天然分子环境.
Bisphenol A （2,2-bis（4-hydroxyphenyl） propane, BPA） is a known endocrine disruptor which possesses estrogenic activity and interferes with the endocrine system. Further, BPA has been shown to adversely affect development and/or reproduction in many animal species. In order to rapidly identify and effectively adsorb BPA,a molecularly imprinted polymer （MIP）,template with BPA,has been synthesized in polar solvent. 4-Vinylpyridine was selected as the functional monomer. UV analysis results revealed BPA and 4- vinylpyridine completed the self-assembly process by noncovalent interaction, which was presumed toπ-π stacking. The complex ratio was 1 ： 2 by calculation. The MIP was prepared in precipitation polymerization and characterized by infrared spectra. It demonstrated that MIP had the necessary characteristics of the structure and successfully accomplished imprinting and reversible separation to BPA. The ChemDraw pictures were used to display the imprinted mechanism of the polymers. The preservation of the mesoporous structure was confirmed visually by scanning electron microscopy （SEM） of MIP. Evidence of imprint sites buried within the pore walls was found through careful characterization of MIP and its comparison to similarly prepared non- imprinted ones. The thermal adsorption experiment examined the specificity recognition and the selective adsorption mechanism. The specificity adsorption was 37.39μmol/g and the imprinted index was 4.31. The separation factors of tetrabromobisphenol A, phenol, atrazine, naproxen and quercetin were 2.51,2.06,2. 14, 2.26 and 2.63 respectively, which showed that molecularly imprinted polymer had a good recognition characteristic to BPA. The recognition factor of the non-imprinted polymers was close to 1 ,which indicated that the adsorption substrate was non-selective. This demonstrated that it was the formation of precise and stable cavities retained the exact memory of the size, shape, and orientation of the functional groups during the templating polymerization steps.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2014年第1期49-55,共7页
Acta Polymerica Sinica
基金
天津市自然科学基金(基金号10JCZDJC21900)和天津市自然科学基金青年基金(基金号13JCQNJC02600)资助项目
关键词
印迹机理
Π-Π堆积
沉淀聚合
印迹指数
双酚A
Imprinting mechanism, π-π stacking, Precipitation polymerization, Imprinted index,Bisphenol A
