聚醋酸乙烯乳液/阴离子型聚氨酯乳液共混体系的研究

Study on the Blending System of Polyvinyl Acetate Emulsion and Anionic Polyurethane Emulsion

自制了羧酸型水性聚氨酯乳液(APU)和聚醋酸乙烯乳液(PVAc),采用共混方法制备了PVAc/APU共混乳液。研究了共混体系的粘接性能和相容性。结果表明,共混体系的粘接性能依赖于共混乳液的共混比例,在PVAc/APU共混比例为70/30时木-木压剪强度最大,共混比例为30/70时木-木PVC剥离强度最高,粘接强度较两种乳液均有显著提高。DSC分析结果显示共混体系有一个Tg,表明两组份有较好的相容性。TEM结果也表明APU粒子在PVAc粒子表面有吸附作用,有利于提高共混体系的相容性。

Carboxyl aqueous polyurethane （APU） and polyvinyl acetate （PVAc） emulsion were synthesized. The PVAe/APU blending emulsions were prepared by blending method. The adhesion property and miscibility of the blending systems were researched, with the results that, the adhesion property and miscibility relied on the blending ratio of the blending compositions. The wood-wood compression shear strength reached the maximum when the ratio of PVAc to APU was 70/30, and the maximal peeling strength appeared when the ratio was 30/70. The adhesion strength was apparently enhanced comparing with the two kinds of pure emulsions. The DSC analysis revealed that, the blending systems had good miscibility for there was only one glass transition temperature （Tg） in different systems with different blending ratio. The TEM results showed that, the APU particles absorbed on the surface of the PVAc particles, this absorption facilitated the miscibility of the blending systems.