水性PU防污自清洁皮革涂饰材料的微结构与性能

Antifouling and self-cleaning coatings have attracted much research interests due to its rich surface microstructure and numerous industrual applications. In this project, we plan to synthesize polyurethane(PU)-g- poly(ethylene glycol)(PEG) copolymers by the macroiniterter technique first, and then fabricate the novel PU-g-PEG/TiO2 nanocomposites by an in situ sol-gel process to have titanium dioxide (TiO2) nanoparticles introduced. It is expected that the PU-g-PEG/TiO2 materials would exhibit both the protein-resistant property of PEG chains and self-cleaning property of nano-TiO2. We will use fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electronic microscopy (SEM), and so on to investigate the microstructure of the copolymer, the density of the grafted PEG chains, and the morphologies and distribution of TiO2 in the PU matrix. Meanwhile, the antifouling and self-cleaning properties of the PU-g-PEG/TiO2 coatings will be detected by using quartz crystal microbalance with dissipation (QCM) and surface plasmon resonance (SPR). The effect of the coatings on the crust leather will also be evaluated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), and water vapor permeability test, etc. By solving some key problems, such as the compatibility between inorganic nanoparticles and organic copolymers, the functional matching and complementary of PEG and TiO2, we will explore the molecular interactions, and establish the relations between preparation parameters, microstructures and properties of the materials. We believe that the results would most benefit to develop environmental leather finishing coatings with antifouling/self-cleaning properties.

生物防污和自清洁材料因其丰富的表面微结构和广泛的工业应用而成为现今科学界关注的一个热点。本项目将利用聚氨酯分子结构的可调节性，采用大分子引发技术将具有防污性能的PEG接枝到聚氨酯侧链，同时基于sol-gel方法原位引入光活性自清洁纳米TiO2，制备新型的水性PU-g-PEG/TiO2共聚物基纳米复合材料。将用FTIR、NMR、XRD、AFM、SEM等研究PU体系的分子结构、PEG接枝链密度和TiO2在PU基体中的分布形态等微观结构，认识分子相互作用；并结合QCM、SPR等研究PU-g-PEG/TiO2涂层表面的抗蛋白吸附和自清洁等性能；考察涂层对坯革的热稳定性、动态力学行为和透水汽性等的影响。通过解决无机纳米粒子与有机聚合物的相容性、PEG和TiO2在性能上的有效匹配与互补等这些关键因素，建立制备参数、材料微结构和宏观性能的关联，为制备高性能防污自清洁环境友好皮革专用涂饰材料提供理论依据。

研究具有防污自清洁功能的高性能环境友好皮革专用PU涂料，既是提高皮革及其制品质量档次与竞争力的关键因素，也是当前制革清洁生产必须解决的瓶颈问题。本项目利用聚氨酯分子结构的可调节性，采用大分子引发技术将具有防污性能的PEG接枝到聚氨酯侧链，同时基于sol-gel方法原位引入光活性自清洁纳米TiO2，制备出新型的水性PU-g-PEG/TiO2共聚物基防污自清洁复合材料。项目研究工作中，发现将磺胺两性离子聚合物以侧链的形式引入到聚氨酯 基体中，所得的涂层具有优异的抗蛋白吸附性能。在成功制备磺胺两性离子聚氨酯膜(iNPU)的基础上，较为系统地研究磺胺两性离子的引入对聚氨酯的结构、涂膜的微观形貌、力学性能和抗菌防霉等性能的影响，及磺胺两性离子聚氨酯的水性化工艺条件。改变合成聚氨酯膜的单体及其配比，可以得到不同性能的水性磺胺两性离子聚氨酯膜，实验制备的一种磺胺两性离子水性聚氨酯乳液稳定，且力学性能可满足皮革中硬涂饰剂的要求。研究可见光响应型TiO2的制备及其对水性聚氨酯结构与性能的影响的课题中，以含Fe3+过氧钛酸溶液为前驱体，采用水热法成功制备了具有可见光响应的改性纳米TiO2溶胶。将此纳米TiO2作为添加剂改性水性聚氨酯，不仅可以改善复合材料的力学性能，而且还成功赋予了复合材料抗紫外、自清洁等性能，制备了一种实用性更强的功能型水性聚氨酯复合材料。通过解决了无机纳米粒子与有机聚合物的相容性、PEG和TiO2在性能上的有效匹配与互补等这些关键因素，研究成果国际学术期刊上发表SCI科研论文11篇，国内核心期刊4篇，申请有应用前景的发明专利10项，已授权发明专利8项，为制备高性能防污自清洁环境友好皮革专用涂饰材料提供理论依据，研发的材料已在企业进行中试阶段。