双羟基染料改性有色水性聚氨酯的制备与性能

Colored waterborne polyurethane modified by dihydroxyl dye

摘要:

研究双羟基染料不同引入方式对水性聚氨酯（WPU）乳液及其成膜性能的影响。采用异佛尔酮二异氰酸酯（IPDI）、聚四氢呋喃（PTMG）、N,N-二甲基甲酰胺（DMPA）和1,4-丁二醇（BDO）合成了水性聚氨酯乳液。将酸性红87作为扩链剂部分替代1,4-丁二醇制备了ARWPUA-1~3有色聚氨酯乳液；作为软段部分替代PTMG制备了ARWPUB-1~3有色聚氨酯乳液；使用物理共混法将染料与水性聚氨酯混合制备了WPU/AR。采用红外光谱和紫外-可见吸收光谱对样品的化学结构进行了表征；研究了不同工艺制备的有色水性聚氨酯的储存稳定性、耐溶剂性能、耐干/湿摩擦色牢度以及力学性能；并采用分子动力学模拟对不同聚氨酯体系进行结合能的分析。实验结果表明，ARWPUA-2具有优异的储存稳定性，可储存6个月以上；在热水、NaOH、HCl和甲苯等溶剂中均不会发生溶解脱色现象；具有良好的耐干/湿摩擦色牢度和较高的力学性能，其拉伸强度由13.8 MPa提升至22.6 MPa，断裂伸长率为810%。

Abstract:

This study investigates the impact of different substitutions of dihydroxyl dyes on the properties of waterborne polyurethane (WPU) emulsion and its film formation. A waterborne polyurethane emulsion is synthesized using isophorone diisocyanate (IPDI), polytetrahydrofuran (PTMG), N,N-dimethylformamide (DMPA), and 1,4-butanediol (BDO). ARWPUA-1~3 colored polyurethane emulsion is prepared by employing Acid red 87 as a chain extender partly instead of BDO, while ARWPUB-1~3 colored polyurethane emulsion is obtained by partly replacing PTMG with a soft segment. WPU/AR is obtained by physical blending of dye and waterborne polyurethanes. The chemical structure of the samples are characterized through FTIR and UV-vis absorption spectroscopy. Furthermore, this paper investigates the storage stability, solvent resistance, color fastness to dry/wet friction, and mechanical properties of the colored waterborne polyurethanes produced through different substitution processes. Molecular dynamics simulation is employed to analyze the binding energy of polyurethane systems prepared via distinct substitution methods. The experimental findings indicate that ARWPUA-2 exhibits excellent storage stability, with a storage time exceeding 6 months. Moreover, It demonstrates resistance to dissolution when exposed to hot water, NaOH, HCl, toluene, and other solvents. The material also exhibits favorable color fastness to dry/wet friction and possesses high mechanical properties, including increased tensile strength from 13.8 MPa to 22.6 MPa, along with an elongation at break of 810%.