使含有氨基的改性硅胶微粒表面的氨基与溶液中的过硫酸盐构成氧化-还原引发体系,实施了甲基丙烯酸二甲基氨基乙酯( DMAEMA)在硅胶微粒表面的引发接枝聚合,制得接枝微粒PDMAEMA/SiO2；又以氯乙胺为试剂,使接枝的大分子PDMAEMA的叔胺基团发生季铵化反应,实现了接枝微粒PDMAEMA/SiO2的季铵化(Quaternization)转变,制得了阳离子性功能接枝微粒QPDMAEMA/SiO2。采用红外光谱(FTIR)、扫描电子显微镜( SEM)及Zeta电位测定等多种手段对两种微粒进行了表征。主要研究了温度对接枝聚合和季铵化转变反应的影响,优化了反应条件。还考察了功能接枝微粒QPDMAEMA/SiO2对阿魏酸的子吸附性能。研究结果表明,采用-NH2//S2 O82-表面引发体系,可有效地实现DMAEMA的接枝聚合,适宜的反应温度为35℃；氯乙胺与接枝微粒叔胺基团之间的季铵化反应可顺利进行,适宜的反应温度为60℃,叔胺基团的季铵化度可达82%。凭借主-客体之间的强静电相互作用并协同以阳离子-π相互作用,功能接枝微粒QPDMAEMA/SiO2对阿魏酸可产生很强的吸附作用,在中性条件下,吸附容量高达187mg/g。%A redox initiating system was constructed by the amino groups on the modified silica gel particles and ammonium persul-phate in the solution,and the surface-initiated graft polymerization of dimethylaminoethyl methacrylate( DMAEMA) was performed, resulting in the grafted particles PDMAEMA/SiO2. Subsequently,the quaternization reaction of the tertiary groups on the grafted particles was carried out with chlorethamin as regeant,and the quaternization transform of the grafted PDMAEMA was realized,re-sulting in the functional grafted particles QPDMAEMA/SiO2 with cationic property. The functional grafted particles were fully char-acterized by several means,such as FTIR,SEM and Zeta potential determination. The effects of temperature on the graft-polymeriza-tion reaction and the quaternization transform were mainly researched,and the conditions were optimized. The adsorption property of the functional grafted particles QPDMAEMA/SiO2 for ferulic acid was examined. The experimental results show that the graft-poly-merization of DMAEMA on silica gel particles can be effectively realized by using the surface initiating system of-NH2//S2O82-,and the suitable temperature is 35℃. The quaternization reaction between chlorethamin and the tertiary amine groups on the grafted particles can be smoothly carried out,and the appropriate temperature is 60℃. At this temperature the quaternization degree( QD) of the tertiary amine groups can reach 82%. By right of the synergism of strong electrostatic interaction and cation-πinteraction,the functional grafted particles QPDMAEMA/SiO2 possess very strong adsorption for ferulic acid,and in the neutral aqueous solution, the adsorption capacity gets to 187mg/g.
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