Preparation of Waterborne Polyurethane Membrane and Its Applications in Microfiber Synthetic Leather

© 2017, Editorial Board of Polymer Materials Science & Engineering. All right reserved. The waterborne polyurethane (WPU) membrane using WPU as polymer was prepared through physical-mechanical foaming. The effects of membrane-forming temperature on the structure and performance of WPU membranes were investigated. The results show that the foam density, surface pore size, mean pore size, crystallinity, air permeability, water vapor permeability, tensile strength and elongation at break of the obtained WPU membrane increase with an increase from 40? to 80? in membrane-forming temperature. When membrane-forming temperature is 80?, the permeability of WPU membrane obtained is optimal. Further, the WPU membranes with the increase of membrane-forming temperature exhibit crack structure. The air permeability and water vapor permeability of the obtained WPU membrane increase with the increase of membrane-forming temperature, and the tensile strength and elongation at break observably decrease with the increase of membrane-forming temperature. On this basis, the WPU microfiber synthetic leather made by dry process has reached the level of A.