透明聚酯型水性聚氨酯的制备与性能研究

聚酯型WPU(水性聚氨酯)具有较高的力学强度和粘接强度,但是其较高的结晶性会导致胶膜透明性较差。以聚丙二醇(PPG)、聚己二酸丁二醇酯二醇(PBA)、异佛尔酮二异氰酸酯(IPDI)、2,2′-二羟甲基丙酸(DMPA)和1,4-丁二醇(BDO)等为原料,制备PPG改性聚酯型WPU。研究结果表明:PPG改性聚酯型WPU的黏度适中,储存稳定性良好;随着PPG含量的不断增加,WPU胶膜的透明性因结晶受阻程度增大而变好,相应胶粘剂的T型剥离强度和拉伸强度下降,而断裂伸长率升高;当w(PPG)=10%～20%时,相应WPU胶粘剂的透明性、T型剥离强度(≥1.97 N/mm)、拉伸强度(≥14.7 MPa)和断裂伸长率(≥421%)俱佳。

Study on preparation and properties of transparent waterborne polyurethane based on polyester polyols

The WPU(waterborne polyurethane) based on polyester polyols had higher mechanics strength and bonding strength,but its higher crystallizability shall lead poor transparence of adhesive films.With poly(propylene glycol)(PPG),polybutyleneglycol adipate(PBA),isophorone diisocyanate(IPDI),2,2′-dimethylol propionic acid(DMPA) and 1,4-butanediol(BDO) as raw materials,a WPU based on polyester polyols modified by PPG was prepared.The research results showed that the WPU based on polyester polyols modified by PPG had moderate viscosity and good storage stability.The transparence of WPU adhesive films was increased because of confined crystallization with increasing PPG contents,the T-peeling strength and tensile strength were decreased but elongation at break was increased for corresponding adhesive.The transparence,T-peeling strength(≥1.97 N/mm),tensile strength(≥14.7 MPa) and elongation at break(≥421%) for corresponding WPU adhesive were all good when mass fraction of PPG was 10%-20%.