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:通过对水溶性硅油浓度的改变,研究其对超临界CO2介质中丙烯酸聚合反应的影响。研究表明水溶性硅油可起到分子量调节剂的作用。随着硅油的加入,产物分子量降低,但当硅油浓度过大时,由于硅油在超临界CO2中溶解度的限制,夹带单体聚沉在反应釜底部形成富单体相,分子量有所上升。此外,扫描电镜照片(SEM)显示不同浓度的水溶性硅油对聚丙烯酸分子形态的影响不同,硅油含量越大,聚丙烯酸分子粒径越小,分子量分布越均匀。
: By changing the concentration of water-soluble silicone oil, the effect of acrylic acid polymerization in supercritical CO2 was studied. Studies have shown that water-soluble silicone oil can play a role as a molecular weight regulator. With the addition of silicone oil, the product molecular weight decreased, but when the silicone oil concentration is too high, due to the limitation of the solubility of silicone oil in supercritical CO2, the entrained monomer concentrated in the bottom of the reactor to form a monomer-rich phase, the molecular weight increased. In addition, SEM images showed that different concentrations of water-soluble silicone oil had different effects on the morphology of polyacrylic acid. The larger the content of silicone oil, the smaller the particle size of polyacrylic acid, the more uniform the molecular weight distribution.