三硝基甲苯分子印迹微球的制备与应用

Preparation and application of TNT molecularly imprinted microspheres

以三硝基甲苯(TNT)为模板分子,丙烯酰胺(AM)为功能单体,采用沉淀聚合法制备分子印迹聚合物MIP。通过紫外光谱法研究TNT和AM之间的相互作用,结果表明TNT与AM之间作用力较强,有助于形成结构稳定、亲和性强的聚合物;利用扫描电镜观测不同制备条件下印迹聚合物的表观形貌,发现乙腈用量为100m L,缓慢的搅拌速率下制备的聚合物形貌较优异;利用红外光谱分析聚合物的结构特征,验证印迹聚合物的制备与模板分子的洗脱;平衡吸附实验表明,MIP对TNT的吸附存在两种作用位点并且吸附量随TNT初始浓度增加而增加;动力学吸附实验发现印迹聚合物对TNT的吸附速率远大于非印迹聚合物;选择性吸附实验中,MIP对TNT表现出较好的特异吸附性能,而对于TNT的结构类似物DNT、RDX吸附能力较差。

The molecularly imprinted polymers（MIP）were prepared by precipitation polymerization method using 2,4,6-trinitrotoluene（TNT）as the template molecule and acrylamide（AM）as the functional monomer. The interaction between TNT and AM was studied by UV spectroscopy. It was found that TNT and AM had a strong force,which could help to form MIP with stable structure and binding ability. The morphologies of the polymers were observed by scanning electron microscopy（SEM）. It was found that the polymers prepared with 100 m L acetonitrile under slow stirring were better than others. The equilibrium adsorption experiments showed that there were two kinds of adsorption sites and the adsorption capacity increased with the increase of initial concentration of TNT. Kinetic adsorption experiments showed that the adsorption rate of MIP was much quicker than that of non-imprinted polymers（NIP）. Meanwhile,the specific adsorption of MIP was also tested. The results showed that MIP had strong specific adsorption properties to TNT,while the adsorption to the structural analogues of TNT（DNT and RDX）was quite weak.