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In this article tetrabutylammonium bromide (TBAB) was first added in buffer to compose a convenient and environmentally friendly system, and enzymatic polymerization of phenol catalyzed by horseradish peroxidase (HRP) could proceed efficiently in this system. When TBAB was added, the most conversion of phenol could reach 99.1%. The phenol polymer was considered to consist of a mixture of phenylene (Ph) and oxyphenylene (Ox) units by IR analysis, and the ratio of phenylene to oxyphenylene units (Ph/Ox) was measured by titration. Moreover, the effects of the dosage of horseradish peroxidase (HRP) and pH value on the conversion of phenol were investigated. The reaction performed very effectively in this novel system when the addition of HRP was only 0.2 mg. In all cases, the weight-average molecular weight calculated by GPC-SLS was in a range from 12000 Da to 30000 Da. The phenol polymer prepared in the present research possessed good thermal stability shown by TG analysis. 相似文献
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探讨了在微波作用下, 聚氯乙烯-三乙撑四胺负载钯配合物(PVC-TETA-Pd)对四苯硼钠与卤代苯的Suzuki反应的催化性能. 实验发现: 在微波功率为200 W时, 在Na2CO3, NaF, KF, NaHCO3等多种碱的存在下, 以DMF的水溶液(V∶V=5∶3)为溶剂, 在无惰性气体保护下, PVC-TETA-Pd催化四苯硼钠与碘代苯在20 min内即可定量反应, 与常规加热方式相比, 节省了大量时间; 同时也证明了四苯硼钠的四个苯基均可参与Suzuki偶联反应; 该催化剂回收再利用3次后, 仍具有较高的催化活性. 相似文献
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荧光增白剂4,4'-双(4-磺酸钠苯乙烯基)联苯新的合成方法 总被引:1,自引:1,他引:0
论述了荧光增白剂4,4'-双(4-磺酸钠苯乙烯基)联苯的合成方法,选择Heck反应作为合成的基本反应.通过研究影响该反应的各种因素,优化实验条件,确定了最佳实验条件为:壳聚糖负载钯为催化剂,用N-甲基吡咯烷酮(NMP)作为溶剂,温度控制在120 ℃,对碘代联苯与对乙烯基苯磺酸钠的比例为1∶3.5,反应25 h,产率达到56.30 %,同时采用红外光谱和质谱对产物进行了表征.并对催化剂进行了回收再利用,为此类产品的绿色工业化生产提供了实验基础. 相似文献
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以苯乙烯及二乙烯苯为原料,通过乳液聚合方法合成了交联聚苯乙烯,然后经硝化、还原制得交联聚(4-氨基苯乙烯)(CL-PAS)载体,在一定条件下负载PdCl2得到淡灰色的交联聚(4-氨基苯乙烯)负载钯配合物(CL-PAS-Pd)。在常规和微波两种加热方式下,考察了碱、溶剂、时间、温度、底物以及原料配比等不同条件下CL-PAS-Pd对四苯硼钠与碘代苯的Suzuki反应催化性能。结果表明,在多种碱、溶剂等条件下催化剂均有较好的催化性能,且可以回收再利用;微波加热可以将反应时间由8h缩短至20min,节约了大量时间。 相似文献
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