半连续乳液聚合法合成纳米硅丙乳液的动力学

Kinetics on Semi-Continuous Emulsion Polymerization of Organosilicone-Modified Acrylate Nanolatexes

以丙烯酸酯、乙烯基三乙氧基硅烷(A151)为单体,采用复合乳化剂合成了有机硅改性丙烯酸酯纳米乳液。研究了有机硅、乳化剂、引发剂、反应温度及功能性单体甲基丙烯酸-2-羟基乙基酯(HEMA)、甲基丙烯酸(MAA)对乳液聚合反应速率的影响。结果表明,纳米硅丙乳液的聚合速率随乳化剂、引发剂、HEMA和MAA质量百分数的增加及反应温度的升高而增大,但随A151质量百分数的增大而减小。纳米硅丙乳液的聚合速率Rp与乳化剂浓度CE、引发剂浓度CI、A151浓度CA151、HEMA浓度CH、MAA浓度CM的关系为Rp=kCE0.2757CI0.1446CA151-0.3672CH0.0941CM0.0576。转化率在20%～80%范围内为恒定速率区,该区聚合反应的表观活化能为42.90kJ/mol。

The kinetics on semi-continuous emulsion copolymerization of organosilicone-modified acrylate nanolatex synthesized from acrylate and triethoxyvinylsilane （A151） as monomers and mixed emulsifiers were studied. The effect of the mass percents of emulsifier,initiator,A151,methacrylic acid 2-hydroxyethyl ester （HEMA） and methacrylic acid （MAA） as well as the reaction temperature on polymerization reaction rate was investigated. The results show that the polymerization reaction rate increases with the mass percents of emulsifier,initiator,HEMA,MAA and reaction temperature,but decreases with the mass percent of A151. The kinetic relationship of the semi-continuous emulsion copolymerization was Rp=kC0.2757EC0.1446IC-0.3672A151C0.0941HC0.0576M. The constant-rate interval is in the monomer conversion of 20%～80%. The apparent activation energy in constant-rate interval is found to be 42.90 kJ/mol.