水性聚氨酯表面施胶剂的制备、改性及应用研究进展

水性聚氨酯（WPU）表面施胶剂具有柔韧性能好、附着力强、结构及性能可控、绿色环保等优点，但其自身交联密度较低，耐水、耐热以及机械强度等性能较差，需进行化学改性才能满足造纸工业应用要求。本文详细综述了WPU表面施胶剂近年来的主要改性方法，包括丙烯酸酯改性、有机硅改性、环氧树脂改性和蓖麻油改性等，并对改性前后WPU表面施胶剂的性能变化进行了分析、评述，为新型WPU表面施胶剂的研究开发提供理论依据。文章重点介绍了多功能WPU表面施胶剂，此类施胶剂在改善纸张表面性能的同时，还赋予了纸张抗紫外、抗菌、荧光增白等特定功能，具有一剂多效的特点。通过对WPU表面施胶剂发展规律的总结，指出绿色环保、低能耗、多功能化是WPU表面施胶剂在造纸工业未来研究的重点。

Recent development of waterborne polyurethane as surface sizing agent: preparation,modification and application

Waterborne polyurethane (WPU) surface sizing agent has gained many attentions in consideration of its good flexibility, strong adhesion, controllable structure and excellent performance. However, neat WPU has low crosslinking density, which results in poor water resistance, insufficient thermal stability and mechanical strength of paper. In this context, it must be properly modified to meet the requirements of paper industry. This work reviewed the recent modification methods of WPU surface sizing agent, including acrylic resin modification, silicone modification, epoxy resin modification and castor oil modification. At the same time, the performance changes of this product were analyzed and reviewed, which provided a theoretical basis for the research and development of new WPU surface sizing agent. It was also introduced multifunctional WPU surface sizing agent, which gave paper specific functions such as ageing resistance, antibacterium and fluorescent brightening. By summarizing the development law of WPU surface sizing agent, it was pointed out that green environmental protection, high performance and multifunctionality were the focus of future research on WPU surface sizing agent in the paper industry.