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采用ω-氯代酰氯试剂氯乙酰氯和氯丁酰氯,在Lewis酸催化剂存在下,于室温下分别与交联聚苯乙烯(CPS)微球进行了Friedel-Crafts酰基化反应,制备了氯代酰基化(chloroacylation,CA)的交联聚苯乙烯微球(CACPS),用红外光谱与佛尔哈德分析法表征了产物的化学结构与组成,研究了各种因素对反应过程的影响.结果表明,在Friedel-Crafts酰基化反应过程中,伴随的副反应─微球表面聚苯乙烯大分子之间的Friedel-Crafts烷基化附加交联反应,不但降低了在CPS微球表面引入氯代酰基的效率,还使微球变脆.在室温(25 ℃)下,以CHCl_3为溶剂、催化剂SnCl_4与白球中聚苯乙烯链节的摩尔比为1.2:1、采用10 mL/g CPS微球的溶剂用量反应5 h,可以达到酰基化反应和烷基化交联副反应的最佳平衡点(此时的氯含量最高).结果还表明,采用氯丁酰氯对CPS微球进行氯代酰基化反应的效果明显好于氯乙酰氯.

Friedel-Crafts acylation reaction of crosslinked polystyrene(CPS) microspheres was conducted in the precence of a Lewis acid catalyst at room temperature using two kinds of ω-chloroacyl chloride,chloroacetyl chloride and chlorobutyryl chloride,and chloroacylation crosslinked polystyrene(CACPS) microspheres were prepared. The chemical structure and composition of the resultant microspheres were characterized and determined by means of infrerad spectroscopy and Volhard methods. The effects of various factors on the chloroacylation reaction were investigated. The experimental results show that the chloroacylation process is always accompanied by Friedel-Crafts alkylation reaction,which is a side reaction leading to additional crosslinking. This side reaction not only decreases the content of the chloroacyl groups on CACPS microspheres,but also makes the property of the microspheres poor. An optimal equilibrium point,at which the chlorine content of CACPS microspheres is the highest,between acylation reaction and alkylation crosslinking reaction can be reached under the following conditions: room temperature,CHCl_3 as the solvent,SnCl_4 as the catalyst,a 1.2:1 molar ratio of catalyst to chain unit of polystyrene of CPS,10 mL used solvent per 1 g CPS microspheres. The result still indicates that the chloroacylation via chlorobutyryl chloride is better than that via chloroacetyl chloride.