摘要： 采用二乙醇胺(DEOA)开环环氧树脂 E-44 制得端羟基环氧树脂(E-OH)，用 E-OH 合成一系列羟基环氧改性水性聚氨酯(EWPU)乳液，并研究了 E-OH 添加量对 EWPU 乳液的粒径及涂膜性能的影响。 核磁氢谱(¹H NMR)测定了 E-OH 的结构和开环率，傅里叶红外光谱(FT-IR)确定了水性聚氨酯(EWPU)的结构，激光粒度仪测定了 EWPU 乳液粒径，热重(TG)测定了 EWPU 的耐热性能。 结果表明:随着 E-OH 添加量增大，EWPU 预聚体黏度增大，乳液粒径增大，乳液稳定性下降。 另外，随着 E-OH 添加量增大，EWPU 胶膜吸水率、溶胀度、拉伸强度和断裂伸长率均出现先增加后降低的特点。 EWPU 胶膜力学强度最高可以达到 26.69 MPa， 断裂伸长率最高可以达到428.35%。综合分析实验数据得到E-OH 在EWPU体系的最佳加入量为2.5%~3.5%。

关键词: 二乙醇胺, 环氧树脂, 改性, 水性聚氨酯

Abstract:

This paper has described the synthesis of hydroxyl group terminated epoxy resin(E-OH) by ring-open reaction of epoxy resin(E-44) with diethanolamine(DEOA),which was then used to prepare a series of E-OH modified waterborne polyurethane (EWPU.The effect of amount of E-OH on EWPU emulsion particle size and film properties was studied. The E-OH's structure and ring-opening ratio were determined by ¹H-NMR. The EWPU's structures were investigated by fourier transform infrared spectroscopy(FT-IR). The EWPU emulsion particle sizes were determined by laser particle size analyzer. Besides, the EWPUs' heat resistance was measured by thermogravime (TG). The study found that the viscosity and particle size of EWPU prepolymers increased, but the stability of emulsion decreased along with the increase of amount of E-OH. In addition, the water absorption rate of EWPUs' films, degree of swelling, tensile strength and elongation at break were increased and then decreased with the increase of amount of E-OH EWPU films' mechanical strength could reach 26.69 MPa, and elongation could reach 428.35%. The optimal amount of E-OH was found between 2.5%~3.5%.

Key words: diethanolamine, epoxy resin, modification, waterborne polyurethane