关键词: 水性聚氨酯, 亲水扩链剂, 磺酸型, 羧酸型

Abstract: Waterborne polyurethane is widely used in many fields，such as coating，medicine and adhesive，and chain extender is one of the key raw materials for the synthesis of polyurethane. Groups introduced on the chain extender with certain characteristics will affect the performance of polyurethane，hydrophilic chain extender can provide waterborne polyurethane good dispersion and emulsification. Currently carboxylic acid and sulfonic acid hydrophilic chain extenders are commonly used materials of anionic chain extenders. In this paper，the definition and function of the chain extender，the kinds of hydrophilic chain extenders were briefly described. The research progress in carboxylic acid and sulfonic acid hydrophilic chain extenders were summarized，the differences in the performance of carboxylic acid and sulfonic acid of waterborne polyurethanes were analyzed in detail. The high water resistance，high flexibility，high solid content and other properties of sulfonic acid type waterborne polyurethane are analyzed in detail，and compared to carboxylic acid type waterborne polyurethane in the performance advantages of all aspects. The research progress in nonionic hydrophilic and amphoteric hydrophilic chain extenders were briefly described，and the development trend of hydrophilic chain extender in the cost，the synthetic route and environmental aspects was also discussed.

Key words: waterborne polyurethane, hydrophilic chain extender, carboxylic acid, sulfonic acid