制备方法对聚氨酯-丙烯酸酯复合乳液性能影响

Influence of preparation methods on properties of polyurethane-acrylate hybrid emulsions

以物理共混、物理复合、引入双键交联3种方法分别制备阳离子聚氨酯-丙烯酸酯(PUA)复合乳液,重点研究制备方法对PUA乳液及乳胶膜性能的影响.粒度分布结果表明:物理共混所得PUA乳液平均粒径最大,为178.7 nm;物理复合所得最小,仅为50.9 nm.透射电镜扫描结果表明:引入双键交联改性所得PUA乳胶粒为球形,呈明显的核-壳结构;物理共混及物理复合所得乳胶粒也呈球形,但粒径分布较宽,且粒子边缘模糊.引入双键交联改性所得PUA乳胶膜的力学性能、耐水性高于物理共混和物理复合改性,其结晶度介于物理复合与物理共混之间.热失重分析表明物理共混方法所得PUA热稳定性弱于其他2种方法.

Three methods of physical blending,physical compound and introduction of double bond to form chemical crosslinked network were respectively used to prepare cationic polyurethane-acrylate （PUA） hybrid emulsions.The effects of preparation methods on the properties of three PUA hybrid emulsions and their films were investigated.PSD results show that the maximum particle size of PUA hybrid emulsion by physical blending is obtained with 178.3 nm,while that by physical compound is only 50.9 nm.TEM indicates that the latexes of PUA synthesized by introduction of double bond to form chemical crosslinked network are spherical with clear core-shell structure.The latexes of PUA synthesized by the other two ways are also spherical,but the latex edge is dim.The tensile properties and water resistance of PUA prepared by the introduction of double bond are better than those by the other two ways,and the crystallinity degree is middle value.TGA results indicate that the thermal stability of physical blending PUA is poorer than those by other two methods.