摘要： 以聚氧化丙烯二醇(N210)和 2，4-甲苯二异氰酸酯(TDI)为原料，以自制的磺酸型亲水单体 1，2-二羟 基 -3-丙磺酸钠(DHPA)作为扩链剂，制备了磺酸型水性聚氨酯乳液;通过性能测试，研究了 R[n(—NCO)∶n (—OH)]值、DHPA含量对乳液及胶膜力学性能的影响，并通过红外光谱对产物的结构进行了表征。结果表明，随着 R值的增大，乳液的黏度下降，胶膜的拉伸强度增大，断裂伸长率下降;当 R=2时，随着 DHPA含量的增加，乳液的平 均粒径变小，乳液的稳定性逐渐增强，胶膜的拉伸强度逐渐增大，断裂伸长率则先增大后减小;当 DHPA含量为 5%时， 胶膜的力学性能最佳;性能测定表明:采用分散和中和同时进行的方式，制备的水性聚氨酯乳液综合性能较好。

关键词: 磺酸型水性聚氨酯 ;R值 ;1, 2-二羟基 -3-丙磺酸钠 ;拉伸强度 ;断裂伸长率

Abstract:

The title waterborne polyurethane emulsion containing both carboxylic and sulfonic groups was synthesized by using toluene diisocyanate(TD)and polyether glycol(N210)as raw materials, and 1, 2-di-hydroxy-3 -propanesulfonic acid salt (DHPA as hydrophilic chain-extending agents. The chemical structure of the product was characterized by FT-IR. The effects of R (the molar ratio of NCO and OH) and content of DHPA on the emulsion and mechanical properties of film were studied. The experiment results show that the viscosity of the aqueous polyurethane emulsion decreases, tensile strength of fil m increases and elongation at break becomes weak with increasing of R value. When R is 2, the stability of the aqueous poly-urethane emulsion and tensile strength increase, but elongation at break increases then decreases wit In-of DHPA. And when DHPA is 5%, the film shows the best mechanical properties. The test results creas showed that the comprehensive properites of emulsion are good when prepared by use of the process in which dispersing process and neutralizing occur at the same time.

Key words: sulfonate-based waterborne polyurethane: R value: 1, 2 -dihydroxy-3-Propanesulfonic acid salt: tensil stenghth, elongation at break