自交联型有机硅氧烷改性丙烯酸乳液的合成

Synthesis of Acrylate Emulsion Modified by Self-cross Linking Organic Silicon

通过核壳乳液聚合法制备自交联型有机硅氧烷改性丙烯酸乳液,探讨了乙烯基有机硅氧烷的种类、用量和添加方式,乳化剂,聚合反应的引发体系和pH值等对乳液涂膜性能的影响规律.研究结果表明,采用含水解阻碍性官能团的乙烯基三异丙氧基硅氧烷能提高自交联硅丙乳液的稳定性,增加乳液中有机硅氧烷的含量达10%以上,从而可大大提高涂膜性能.此外,当采用60/40～80/20的添加方式添加乙烯基有机硅氧烷、反应型乳化剂、前期过氧化物引发和后期氧化还原引发的混合引发体系,以及保持体系的pH值在4.5～7的范围内时,能降低聚合过程中有机硅氧烷的水解和缩合反应程度,提高乳液涂膜的交联密度以及耐水耐溶剂等性能,制备出涂膜综合性能优异的自交联型硅丙乳液.

The self-cross linking organic silicon modified acrylate emulsion was synthesized by core/shell emulsion polymerization technique. The effects of species, adding amount and addition procedure of organic ethenyl silicone, and the effects of emulsifier, initiation system and pH value on the film performance were studied. The experimental results show that using hinder organic silicone monomer with isopropoxy and ethenyl can increase organic silicone level up to 10%, and improve the emulsion stability and film performance. Furthermore, using 60/40-80/20 post addition of organic silicone, reaction surfactant, heat-decomposition and oxido-reduction initiation system, and adjusting pH value to 4.5-7 can decrease the degree of organic silicone hydrolysis and fasculation during polymerization. Doing so, the degree of film crosslinking can be increased, the water resistance and solvent resistance of film can be improved too, and a kind of self-cross linking organic silicon modified acrylate emulsion with good comprehensive performance can be achieved.