无氟水性聚氨酯拒水剂的合成及其在棉织物上的应用

Synthesis of Fluoride-Free Water-Repellent Agent of Waterborne Polyurethane and Its Application on Cotton Fabric

以异佛尔酮二异氰酸酯(IPDI)、聚四氢呋喃(PTMG)、二羟甲基丁酸(DMBA)、丙烯酸羟乙酯(HEA)、三乙胺(TEA)为主要原料合成了双键封端的阴离子型水性聚氨酯乳液,聚氨酯与丙烯酸十八酯(SA)发生共聚,制备出无氟水性聚氨酯丙烯酸酯拒水乳液,将其应用于棉织物的拒水整理。讨论了 R 值(IPDI中—NCO与PTMG、DMBA中总的—OH的摩尔比值)、亲水基含量、亲水基加入方式、单体浓度对聚氨酯乳液性能的影响。以静态水接触角反映整理后棉织物的拒水性能,并以傅里叶变换红外光谱、扫描电子显微镜、PhabrOmeter织物手感评价系统对整理后织物进行表征。结果表明, R 值为1.3、亲水基含量为4.5%、单体总质量分数为20%时,得到的聚氨酯乳液具有良好的外观和贮存稳定性,对应制备出的聚氨酯丙烯酸酯拒水乳液粒径较小、分布较窄,且具有较好的热稳定性。整理后织物的水接触角可达138°,拒水效果良好,同时织物具有柔软的手感。

Double-bond terminated anionic waterborne polyurethane (WPU) emulsion was prepared with isophorone diisocyanate (IPDI), poly(tetramethylene oxide glycol)(PTMG), 2,2-dimethylolbutanoic acid (DMBA), 2-hydroxyethyl acrylate (HEA) and triethylamine (TEA). Fluoride-free waterborne polyurethane-acrylate (WPUA) emulsion was prepared by copolymerization of WPU and stearyl acrylate. WPUA was applied on cotton fabric to achieve hydrophobic property. The influence of isocyanate index R (the mole ratio of -NCO and -OH of PTMG and DMBA), hydrophilic monomer content, addition method of hydrophilic monomer and monomer concentration were investigated. The hydrophobic property of finished cotton fabric was proved by static water contact angle. Chemical group of WPUA was characterized by Fourier transform infrared spectrum (FTIR), surface morphology of fabric was presented by scanning electron microscopy (SEM), and the handle of fabric was tested by PhabrOmeter fabric handle evaluation system. The results show that the WPU emulsion has good appearance and storage stability when isocyanate index R is 1.3, hydrophilic monomer content is 4.5% and monomer concentration is 20%. The corresponding prepared WPUA emulsion has smaller particle size, narrow distribution and good thermal stability. The contact angle of finished cotton fabric can reach 138°with good hydrophobic property and good softness.