中空桔瓣型超细纤维/水性聚氨酯合成革的制备及性能

以聚酯-聚酰胺6(PET-PA6)中空桔瓣型超细纤维非织造布为基布,以水性聚氨酯(WPU)膜为聚合物涂层,经干法移膜技术得到了中空桔瓣型超细纤维/水性聚氨酯(PET-PA6/WPU)合成革,实现了超纤革的绿色化制备。通过场发射扫描电镜(FESEM)等测试手段表征了PET-PA6中空桔瓣型超细纤维非织造布的结构性能,系统研究了发泡倍率对WPU膜形态结构和性能的影响规律,分析了PET-PA6/WPU合成革的结构、透气透湿和物理力学性能。结果表明:PET-PA6中空桔瓣型超细纤维非织造布裂离后单根纤维的直径介于2.2~5.5μm之间,且其性能满足纺织品合成革用非织造基布的使用要求。当发泡倍率为100%时,所制备WPU膜为致密无孔结构,透气量和透湿率分别为14.72L/(m~2·s)和3 686.84g/(m~2·24h)。随着发泡倍率的增加,所制备WPU膜具有通透型泡孔和有孔表面,平均孔径、透气量和透湿率均依次增大。其中,当发泡倍率为250%时,WPU膜的透气量和透湿率分别达到169.43L/(m~2·s)和5 209.09g/(m~2·24h)。所制备的PET-PA6/WPU超纤革为三层复合结构,包括基布层、发泡层和面层,且其透气量为0.45L/(m~2·s),断裂强力为纵向138.40N、横向96.60N,断裂伸长率为纵向72.70%、横向101.80%,撕裂强力为纵向63.20N、横向88.20N,剥离强力为水解前15.86N、水解后15.61N,褶皱回复角为纵向149.30°、横向151.80°,均优于同类型的海岛针织合成革和真皮,同时透湿率高达1 673.8g/(m~2·24h),接近于真皮。

Preparation and properties of hollow segmented-pie microfiber/waterborne polyurethane synthetic leather

The waterborne polyurethane (WPU)microfiber synthetic leather(PET-PA6/WPU)using segmented-pie microfiber nonwoven as the base and WPU membrane as the polymer coating was prepared through dry transfer-coating method.The method realized the greening preparation of microfiber synthetic leather.The structure and performance of PET-PA6 hollow segmented-pie microfiber nonwoven were firstly investigaed by FESEM,and then the effect of foaming ratio on the structure and performance of WPU membranes was systematically studied,finally the structure,air permeability,water vapor permeability and physical mechanical properties of PET-PA6/WPUwere analyzed.The results show that the fiber diameter size of PET-PA6 hollow segmented-pie microfiber nonwoven is between 2.2-5.5μm,and its performance meets the using demand of textiles-nonwoven for synthetic leather. When the foaming ratio is 100%,the structure of the obtained WPU membrane is dense,and its air permeability and water vapor permeability are 14.72 L/(m2·s)and 3686.84 g/(m2·24 h),respectively.The WPU membrane exhibites connecting bubble hole and porous surface,and its mean pore size,air permeability and water vapor per-meability increase with the increase of foaming ratio.When the foaming ratio is 250%,the air permeability and wa-ter vapor permeability are 169.43 L/(m2·s)and 5209.09 g/(m2·24 h),respectively.The PET-PA6/WPU micro-fiber synthetic leather is in a three-layer configuration,including fabric layer,foam layer and surface layer.The air permeability of PET-PA6/WPU leather is 0.45 L/(m2 ·s),tensile strength of perpendicular and parallel are 138.40 N and 96.60 N,elongation at break of perpendicular and parallel are 72.70% and 101.80%,tear strength of perpendicular and parallel are 63.20 N and 88.20 N,peeling strength of before hydrolyze and after hydrolyze are 15.86 N and 15.61 N,and creasy recovery angle of perpendicular and parallel are 149.30°and 151.80°,which are better than knitting synthetic leather and real leather.The water vapor permeability of PET-PA6/WPU synthetic leather reaches 1673.8 g/(m2·24 h)closing to real leather.