基于“点击化学”构建胶原蛋白修饰超细纤维合成革基材及其吸湿透湿性研究

Sea-island superfine fiber synthetic leather belongs to high-grade simulated leather. It has many characteristics and advantages better than natural leather, especially mechanical strength, homogeneity and processing adaptability. Compared with natural leather, the wearing comfort of superfine fiber synthetic leather is worse due to its poor moisture absorbption and permeability. Therefore, the study on improving moisture absorption and permeability of superfine fiber synthetic leather has become a hot topic. This project is put forward that the collagen can "click", modify polyamide fiber of superfine fiber synthetic leather base material by method of "click chemistry", for improving moisture absorption and permeability of the superfine fiber synthetic leather base material, and health and wearing comfort performance of end products. At the same time, the target will be realized that superfine fibre synthetic leather simulate natural leather from structure to function. In the process the industrial collagen extracting from leather waste is utilized and modified for getting unsaturated collagen system, which is used to "click" and modify thiol-polyamide fibre as a foreign assistance molecules. The structure-function relationship of collagen’s dispersed state, distribution regularities in the superfine fiber synthetic leather base material and moisture absorption and permeability of it is built by studying the ultrastructural characteristics of collagen and superfine fiber synthetic leather base material. The implementation of project have the theoretical research significance and great practical value for recycling waste leather.

超细纤维合成革属高档仿真皮产品，具有很多的特性和优点，特别是在物理机械性能、质量均一性和加工适应性方面是优于天然皮革。但与天然皮革相比，其吸湿透湿性很差，穿着闷热，所以对此性能的提升已经成为行业亟待解决的热点问题。本项目提出用“点击化学”方法构建胶原蛋白“点击”修饰超细纤维合成革基材中的聚酰胺纤维，以提高超细纤维合成革基材的吸湿透湿性为目的，提升终端产品的卫生性能及穿着舒适性。同时，实现超细纤维合成革对天然皮革从结构模拟到功能模拟的目标。实施中利用废弃皮革提取的工业胶原蛋白进行改性，构建相应的胶原蛋白化学接枝改性的不饱和化学体系，并将其作为外源分子来“点击”修饰巯基化聚酰胺纤维。并结合胶原蛋白与超细纤维合成革基材的超微结构特点，研究不同分子质量的胶原蛋白在基材中的分散状态、分布规律与基材的吸湿透湿性的构效关系。本项目的立项与实施对于废弃皮胶原的资源化利用也具有理论研究意义和很好的实用价值。

超细纤维合成革属高档仿真皮产品与天然皮革相比，其吸湿透湿性很差，穿着闷热，所以对此性能的提升已经成为行业亟待解决的热点问题。本项目用点击化学方法将研究构建废弃胶原蛋白点击修饰超细纤维合成革基材中的聚酰胺纤维，以提高超细纤维合成革基材的吸湿透湿性。分别选用了两种分子量的胶原蛋白，制备了“线性”和“微球”两种不同形态的乙烯基胶原蛋白（CMA）。并系统研究了聚酰胺纤维表面巯基化方法和优化CMA点击修饰聚酰胺纤维的反应条件。结果表明：制备USFSLB-S-CMA的最优反应条件为紫外辐照时间5h，引发剂浓度为0.006%，接枝率50%。当CMA取代度为50%时，所得基材的SWVT提升了43%。同样，当CMA取代度为73%时，LWR提升602.4%。乳液法制备不饱和体系胶原蛋白微球时，乙烯基胶原蛋白溶液浓度为15 wt%，转速为800 r/min，戊二醛和水相体积比为1:25，以及水油相体积比为1:5，乳化剂和油相的体积比为1:50时，制备的CMAs的平均粒径为21.2μm。当乙烯基胶原蛋白微球溶液浓度为6 wt%，引发剂用量为0.008 wt%，辐照时间为5 h时，基材的接枝率为25.3%，基材LWR提升了235.7%。当CMA与Cr/ST质量比为1:1，常温下，转速250 rpm反应20 min，所得微球表面光滑，粒径分布较为均匀，平均粒径为2～3 um。当微球浓度为6 wt %，引发剂浓度为0.006 wt %，辐照时间为4 h时，接枝率可达31.3%。被修饰基材的透湿性提高了41%，LWR提升了79.7%。通过分析胶原蛋白在基材中的存在形态和分散规律发现，基材的吸湿透湿性提升除了增加亲水性基团外，更重要的是构建微观联通的空隙结构。本方法所制得的基材的耐水洗、耐酸、耐碱、耐溶剂性能优良，稳定性好，既提升了基材的吸湿透湿性也增加了基材的耐用性，同时实现了废弃资源化利用。