水性聚氨酯胶粘剂固含量提高策略的研究探索

Research and exploration of strategies for increasing solid content of waterborne polyurethane adhesive

摘要:

随着环保意识和法规的加强,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产品在胶粘剂领域的主要问题之一是固含量,产品中过多的水会带来干燥、生产效率以及粘接性能方面的问题。本文综述了近年来关于制备高固含量低黏度的WPU的研究方法: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、超支化结构等。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、水合层厚度以及粘度等固含量受限制的因素,列举和阐述了相应的解决方案。通过提高固含量,将能解决水性聚氨酯胶粘剂干燥慢、施胶量不够的问题,对优化WPU胶粘剂的制备和使用有重要的实际意义。

Abstract:

With the strengthening of environmental awareness and regulations, waterborne polyurethane (WPU), as 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 solid content. Excessive water content in the product leads to problems in drying, production efficiency, and adhesive performance. This paper provides a review of research methods for preparing high solids low viscosity WPU in recent years, including optimizing the phase inversion process, increasing space utilization, reducing hydration layer, combining internal and external emulsification methods, and hyperbranched structures. The review summarizes the impact of different factors on the phase inversion process and explains how to optimize this process through changes in techniques and equipment. Suggestions are 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 can be resolved. This review has practical significance for optimizing the preparation and application of WPU adhesives.