改性MDI基混合软段型水性聚氨酯的合成及应用

Synthesis and application of modified MDI based waterborne polyurethane with mixed soft segments

以改性MDI和二羟甲基丙酸为硬段,以聚碳酸酯二醇和聚丙二醇为软段,通过溶剂法合成水性聚氨酯乳液,并将其与固化剂混合,制得双组份水性聚氨酯胶膜,并研究胶膜的力学性能和耐水性能;将双组分水性聚氨酯涂覆在棉布表面,通过扫描电镜观察涂层织物表面形貌.结果表明:随着NCO与OH摩尔比的增大,胶膜的拉伸强度先增大后减小;随着DMPA含量的增大,吸水率先上升后下降;随着PCDL与PPG摩尔比的减小,胶膜的拉伸强度和吸水率都随之减小;经过双组份水性聚氨酯处理的织物表面形貌平整.

By using modified MDI and DMPA as hard segment,PCDL and PPG as soft segment,waterborne polyurethaneemulsions were synthesized through solvent method,and then the emulsions and curing agent were mixed togetherto form 2K -WPU membranes. The mechanical property and water resistance of 2K -WPU membranes werestudied. And 2K-WPUs were coatted on the surface of cotton fabrics and the surface morphologies were observedthrough SEM. The results show that with the enlargement of NCO/OH mole ratio,the tensile strength of 2K-WPUmembrane increases firstly,and then decreases. With the enlargement of the content of DMPA,the waterabsorption of 2K-WPU membrane increases firstly and then decreases. With the decrease of PCDL/PPG moleratio,the tensile strength and the water absorption of 2K-WPU membrane decrease. The surface of coatted fabricsbecomes smooth after treated with the 2K-WPU.