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丙烯酰胺微乳液聚合条件的研究 总被引:2,自引:0,他引:2
采用微乳液聚合方法合成了相对分子质量大于1000万的速溶聚丙烯酰胺(PAM).研究了聚合条件对产物分子质量的影响,诸如单体浓度、引发剂、温度、pH值、氨、脲及乳化剂的用量对PAM分子质量的影响,并用傅里叶变换红外光谱和扫描电镜对聚合物进行了表征,分析了产品速溶原因. 相似文献
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丙烯酸酯微乳液聚合研究 总被引:1,自引:0,他引:1
重点研究以反应型乳化剂(DS6)为主组成复配乳化剂体系,进行间歇式微乳液聚合,通过控制聚合温度、加入功能单体等因素,制备出平均粒径小至21.6nm,粒径分布窄(Poly.=0.109),固含量可高达25%的聚合物(PMMA)微乳液,同时还发现,在这类体系中,其聚合动力学特征是:只存在着明显的增速期和减速期两个阶段。 相似文献
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有机高分子絮凝剂是目前国内外普遍采用的高效污水处理剂,被广泛应用于循环用水、工业废水的处理及污泥脱水等过程。用于絮凝技术的有机高分子絮凝剂与无机絮凝剂相比,具有用量少,絮凝速度快,受共存盐类、pH值及环境温度影响小,生成污泥量少且易处理等优点,在节约用水、强化水质处理和提高水的回用率等方面带来显著的经济效益。聚丙烯酰胺类(PAM)各种离子型有机高分子絮凝剂,由于具有分子量大、官能团多等特点,在市场上占有的份额较大,特别是近些年国内环保执法力度的加强和有关企事业单位对其认识的提高, 相似文献
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The oil/water microemulsion polymerizations of alkyl (methyl (MA), ethyl (EA), butyl (BA), hexyl (HA) and 2-ethylhexyl (EHA)) acrylates initiated by a water-soluble (ammonium peroxodisulphate (APS)) initiator were investigated. The rate of polymerization versus conversion curve shows two inconstant intervals. The maximum rate of polymerization of MA, EA, BA and EHA is found to be proportional to the 0·53, 0·17, 0·46 and 0·59 powers of the APS concentration and to the first power of the monomer (MA, BA and EHA) concentration. Homogeneous (solution) radical polymerization is operative in the MA, BA and EHA systems. The strong rate dependence on the EA monomer concentration is assumed to be caused by both the polymerization within the micelle core and the gel effect. The particle size was observed to increase with conversion in the EA and BA runs and to decrease in the EHA and HA runs. The number of particles increased with conversion during the whole polymerization. The polymer particles grow by recruiting monomer and emulsifier from the free monomer-swollen micelles and dead particles. © 1997 SCI. 相似文献