氮丙啶/聚氨酯复配乳液膜性能表征及其表面施胶性能

采用氮丙啶对阴离子水性聚氨酯交联改性,制备了氮丙啶改性水性聚氨酯乳液。研究表明:当n(NCO)/n(OH)=1.6,氮丙啶用量为2.5%时,此水性聚氨酯乳液具有优异的表面施胶性能,以质量分数为1%的氮丙啶/聚氨酯复配乳液进行表面施胶时,纸张的耐折度达到125次,湿强度为36.2%,施胶度为67s。通过红外、力学性能及原子力显微镜对聚合物结构及膜性能进行了表征,红外表明氮丙啶与聚脲氨酯链段参加反应生成酯;力学性能显示聚氨酯胶膜的拉伸性能得到提高,断裂伸长率变小;原子力显微镜显示氮丙啶/聚氨酯复配乳液膜表面粗糙度增加,提高了纸张表面的施胶度。

Properties and sizing performance of emulsion membrane blended aziridine with waterborne polyurethane

The aziridine/polyurethane emulsion was prepared by aziridine crosslinked polyurethane. The results show that the emulsion owns excellent sizing property when n（NCO）/n（OH）=I.6, w（aziridine）=2.5%, and with 1.0% polymer emulsion addition, the folding endurance 125 times, wet strength of 36.2% and sizing degree 67s can be reached. Finally, the polymer was characterized with FTIR and mechanical properties. AFM, FTIR indicate that the aziridine can be formed ester structure with the polyurea polyurethane. It was also found that the tensile strength of films modified polyurethane increases and the elongation at break decreases with increasing the aziridine, the smoothness of the films of waterborne polyurethane decreases when modified by aziridine, resulting in the rise in sizing degree.