高固含量苯丙微乳液的合成及其对涂料性能的影响

Synthesis of High Solid Content Styrene-acrylate Micro Emulsion and Its Influence on the Coatings' Properties

以丙烯酸（AA）、甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）、苯乙烯（St）为主要原料，采用种子聚合法合成了高固含量苯丙微乳液，利用红外光谱（FI—IR）仪、粒径分析仪等对合成乳液进行了表征；以所合成的苯丙微乳液为胶黏剂制备了涂料，研究了苯丙微乳液对涂料流变性及保水性的影响，并与传统的苯丙乳液进行比较。结果表明，所合成的苯丙微乳液粒径主要集中分布在60～90nm之间，平均粒径为75．8nm。在相同剪切速率下，苯丙微乳液涂料黏度比苯丙乳液涂料黏度大；当剪切速率足够高时，两种涂料的黏度相近，且趋向一个平衡值。与苯丙乳液涂料比较，苯丙微乳液涂料的弹性模量更大，保水性更好。以苯丙微乳液为胶黏剂的涂布纸表面强度显著提高，但涂布纸的平滑度和光泽度略有下降。

The high solid content styrene-acrylate micro emulsion was synthesized using acrylic acid （AA）, methyl acrylate （MMA）, butyl acrylate （BA）, styrene （St） as the raw materials by seeded emulsion polymerization, and characterized by FT-IR and particle size analyzer; The coatings for the paper coating was prepared by using the styrene-acrylate micro emulsion, whose effect on the rheological properties and water retention of the coatings was studied. The results showed that the particle of the styrene-acrylate micro emulsion ranged from 60 ~ 90 nm, the average particle sige was 75.8 nm; On the same condition of shear rate, the viscosity of the coatings prepared by styrene-acrylate micro emulsion was higher than the coatings prepared by styrene-acrylate emulsion; When the shear rate was high enough, the viscosities of the two kinds of coatings were similar and tended to an equilibrium value. Compared with the coatings prepared by styrene-acrylate emulsion, the coatings prepared by styrene-acrylate micro emulsion had a bigger elastic modulus and a better water retention properties. When the com- ings contained styrene-acrylate micro emulsion, the surface strength of the coated paper could be improved substantially, but the smoothness and gloss decreased a little.