内交联型水性聚氨酯的制备及其性能研究

Preparation and property of the internal crosslinking waterborne polyurethane

以二聚酸聚酯二元醇(By3022)和异佛尔酮二异氰酸酯(IPDI)为原料,二羟甲基丙酸(DMPA)和1,4-丁二醇为扩链剂,丙三醇为内交联剂,合成一系列的水性聚氨酯(WPU)。采用傅里叶红外光谱仪对WPU分子结构进行表征,并探讨了丙三醇加入量对WPU乳液粒径、胶膜的拉伸强度、胶膜的玻璃化转变温度以及吸水率的影响。结果表明:随着丙三醇加入量的增多,乳液的粒径逐渐增大,分布逐渐变宽,胶膜的拉伸强度变大,断裂伸长率减小,吸水率降低。当丙三醇的加入量为0.77%时,胶膜的拉伸强度达到最大,为16.12MPa,断裂伸长率为688%。

A series of internal crosslinking waterborne polyurethanes were synthesized by dimer acid polyester diol（By3022）and isophoronediisocyanate（IPDI）,with dimethylol propionic acid（DMPA）and 1,4-Butylene glycol as chain extender,glycerol as crosslinking agent.The structure of polyurethanes was characterized by reflectance infrared spectroscopy and the effect of glycerol content on the particle size of WPU emulsion,the tensile strength,the glass transition temperature and the water absorption were studied.The results showed that with the increase of glycerol content,the particle size of emulsion increased,distribution widened gradually,the tensile strength of film increased,the elongation at break and water absorption reduced.When the content of glycerol was 0.77%,the tensile strength reached the maximum value 16.12 MPa,and the elongation at break was 688%.