以对羟基苯甲酸(p-HB)为模板分子,从4-乙烯基吡啶(4-VP)、丙烯酰胺(AM)和甲基丙烯酸(MAA)3种具有代表性的单体中,选择最适宜制备p-HB分子印迹聚合物的功能单体.首先采用分子力学方法计算了p-HB与功能单体4-VP、AM和MAA的结合能,其强度顺序为:4-VP>AM>MAA.采用紫外光谱法分析了p-HB与各功能单体之间的相互作用情况,发现其相互作用强弱顺序同样为:4-VP>AM>MAA.然后测定了由各功能单体合成的p-HB分子印迹聚合物的静态饱和吸附量.结果显示,以4-VP为功能单体合成的分子印迹聚合物的饱和吸附量最大,AM次之,MAA最小.这一结果与分子力学计算及紫外光谱分析相吻合,表明4-VP为3种单体中最适宜制备p-HB分子印迹聚合物的功能单体,同时表明分子力学计算及紫外光谱分析可用于分子印迹聚合物合成功能单体的选择.最后,考察了以4-VP为功能单体合成的p-HB分子印迹聚合物的分子识别选择性,发现其对模板分子p-HB的静态吸附分配系数明显高于其他结构类似物,p-HB与同分异构体邻羟基苯甲酸(SA,o-HB)之间的吸附分离因子达到1-4.%Molecularly imprinted polymers (MIPs) using p-hydroxybenzoic acid (p-HB) as template, 4vinylpyridine (4-VP), acrylamide (AM) and α-methylacrylic acid (MAA) as functional monomers were prepared separately. First, the binding energy of p-HB with the above monomers is calculated by using the molecular mechanics method. The order of binding energy of p-HB with different monomers is 4-VP＞AM＞MAA. Second, the interaction strength between p-HB and different monomers is studied by UV analysis, which is in the same order (4-VP＞AM＞MAA). Third, the static adsorption experiments of the MIPs using 4-VP, AM or MAA as functional monomer show that the binding capacity order of these MIPs is also 4-VP＞AM＞MAA, the same with those from molecular mechanics calculation and UV analysis.The results demonstrate that 4-VP is the best among the three monomers, and molecular mechanics calculation and UV analysis can be used for the selection of a functional monomer for the synthesis of MIPs. Finally, the selectivity of the imprinted polymer made with 4-VP is also studied. The static adsorption distribution coefficient of p-HB is much higher than that of other analogs, and the separation factor between p-HB and o-HB is 1.4.
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