自乳化型聚氨酯脲乳液的制备与表征

以聚氧化丙烯二元醇为软段，甲苯二异氰酸酯、二羟甲基丙酸、２—甲基—１，３—丙二醇、乙二胺和二乙烯三胺为硬段，通过不同的方法合成了一种新型的自乳化型聚氨酯脲乳液（ＡＰｕ）。并用红外光谱、示差扫描量热仪、万能拉伸机和溶胀性实验对乳液胶膜的性质进行了表征；同时测定了乳液的高温稳定性。结果表明，在硬段之间和软段与硬段之间同时存在着氢键作用，这促使软段相的Ｔｇ向高温移动。比较两种不同方法合成的ＡＰｕ，发现，二步法ＡＰｕ具有比较规整的硬段结构，离子基团分布比较均匀，乳液的稳定性和材料的力学性能较好，但耐水性较差。

PREPARATION AND CHARACTERIZATION OF SELFEMULSIFYING POLYURETHANE-UREA EMULSION

A novel polyurethane-urea emulsion was synthesized through different methods from poly(propylene oxide)diol,toluene diisocyanate,dimethylol propionic acid,2-methyl-1,3-propane diol,ethylenediamine and diethylene triamine.The properties of emulsion-cast films were characterized by IR,DSC,tensile measurement and swelling test,and the high temperature stability of emulsion was also observed. It was found that hydrogen bonds existed not only in the hard segments,but also in the soft segments.Comparing with the structural behavior of such emulsions,the product synthesized throgh two-stage method was more order in the domains rich in hard segments and ionic groups along polymer chains were well distributed, thus resulting in an elevation in the stability of the emulsion and mechanical properties of film except a lower resistivity against water.