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采用氧化还原引发体系——异丙苯过氧化氢/硫酸亚铁/乙二胺四乙酸钠盐/甲醛合次硫酸氢钠(CHP/FES/EDTA/SFS),引发丙烯酸丁酯种子乳液聚合。系统考察了该引发体系的引发机理及其组分的配比及用量等因素对聚合反应动力学的影响。研究表明,聚合反应速率和单体的总体转化率皆随CHP或SFS的用量增加而增加;CHP/SFS的最佳物质的量比为1.10/3.81,并非传统认知的等物质的量比;另外,EDTA/FES的最佳物质的量比为(2.19×10-5)/(7.12×10-6)。聚合反应速率随着Fe2+用量的增加先增加后降低。随着反应的进行,体系的pH值降低。并针对发现的极限转化率现象(转化率≤20%),从实际络合常数和反应速率的角度进行了解释。
Cumene hydroperoxide / ferrous sulfate / ethylenediaminetetraacetic acid sodium salt / formaldehyde / sodium formaldehyde sulfoxylate (CHP / FES / EDTA / SFS) were initiated by the redox initiator system to initiate the emulsion polymerization of butyl acrylate seed. The mechanism of the initiation mechanism of the initiator system, the ratio of the components and the amount of the initiator and the amount of the initiator on the polymerization kinetics were systematically investigated. The results showed that both the polymerization rate and monomer conversion rate increased with the increase of CHP or SFS. The best molar ratio of CHP / SFS was 1.10 / 3.81, which was not the same as that of traditional cognition. In addition, the optimal ratio of EDTA / FES was (2.19 × 10 -5) / (7.12 × 10 -6). The polymerization rate increased first and then decreased with the increase of Fe2 + dosage. As the reaction proceeds, the pH of the system decreases. In the light of the observed limit conversion (conversion ≤ 20%), this is explained in terms of actual complexation constants and reaction rates.