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本文叙述了在含有羧基的聚乙烯醇纤维上不伴生均聚物的接枝共聚法。 通过碱处理后聚乙烯醇纤维与氯代醋酸钠的相互作用在大分子中引入了羧基。研究了碱浓度、时间、一步二步法等因素对反应的影响,获得了适宜的引入羧基条件。 在引入羧基的聚乙烯醇纤维上,首次用氧化还原系统H_2O_2-Fe~(++)引发接聚获得了高接聚量不伴生均聚物的接聚法。从实验结果中得出,当在聚乙烯醇大分子中含有少量羧基时,可大大减少均聚物的生成,但是要使接聚反应中不伴生均聚物,不但要引入羧基,而且必须将产生大分子游离基的引发过程与接聚反应分开。 得出了产生大分子游离基的引发时间和温度对接聚反应的重要影响规律。同时也研 究了pH值、单体浓度对接聚量的影响,并用此法进行苯乙烯、丙烯酸甲酯、丙烯酸的接聚,得到基本相同的效果。
This paper describes graft copolymerization without homopolymers on carboxyl-containing polyvinyl alcohol fibers. The carboxyl group is introduced into the macromolecule by the interaction of polyvinyl alcohol fiber and sodium chloroacetate after alkali treatment. The influence of alkali concentration, time, one-step two-step method and other factors on the reaction was studied, and the appropriate introduction of carboxyl groups was obtained. In the introduction of carboxyl-based PVA fibers, the redox system H_2O_2-Fe ~ (++) initiates the first graft copolymerization to obtain the high graft copolymerization without homopolymerization. It is concluded from the experimental results that when a small amount of carboxyl groups are contained in the polyvinyl alcohol macromolecule, the formation of homopolymers can be greatly reduced. However, in order not to cause homopolymerization in the polycondensation reaction, not only carboxyl groups but also The initiation of macromolecular free radicals is separated from the polyaddition reaction. The main influencing rule of polymerization time and temperature on the polymerization of macromolecule free radicals was obtained. At the same time, the effects of pH value and monomer concentration on the amount of butadiene polymerization were also studied. By this method, styrene, methyl acrylate and acrylic acid were agglomerated to obtain substantially the same result.