水性聚氨酯胶黏剂固含量提高策略的研究探索

Research and exploration on strategies for solid content increment of waterborne polyurethane adhesive

随着环保意识和法律法规的加强,水性聚氨酯(WPU)作为一种环境友好型的水性树脂得到了广泛的应用和研究。目前,WPU产品在胶黏剂领域的主要问题之一是固含量低,产品中过多的水分会带来生产效率以及黏接性能方面的问题。该文综述了近年来制备高固含量、低黏度WPU的方法:优化相反转过程、增大空间利用率、减少水合层、内外乳化法结合、超支化结构及复合改性以提高固含量。总结了不同因素对相反转过程的影响,并阐述了如何通过改变工艺和设备来优化相反转过程。针对乳液粒子堆积密度极限、水合层厚度以及黏度等固含量受限制的因素,阐述了相应的解决方案。提高固含量能解决WPU胶黏剂干燥慢、施胶量不够的问题,对优化WPU胶黏剂的制备和使用有重要的意义。

With the strengthening of environmental awareness and regulations,waterborne polyurethane(WPU),an environmentally friendly water-based resin,has been widely applied and studied.Currently,one of the main issues with WPU products in the adhesive field is the low solid content.Excessive water content in the product leads to problems in drying,production efficiency,and adhesive performance.Herein,the preparation methods for high solid content and low viscosity WPU,including optimizing the reverse transformation process,increasing the space utilization rate,reducing the hydration layer,internal and external emulsification,hyperbranched structure and composite modification,in recent years were reviewed.The effect of different factors on the phase inversion process was summarized,and the reverse rotation process optimization strategy by changing the technology and equipment was expounded.Solutions were presented for addressing factors that restrict solid content,such as limitations in emulsion particle packing density,hydration layer thickness,and viscosity.By increasing the solid content,the slow drying and insufficient bonding capacity issues in waterborne polyurethane adhesives could be resolved,which had practical significance for optimizing the preparation and application of WPU adhesives.