Study of a new novel process for preparing and co-stretching PTFE membrane and its properties

A new idea regarding improvement of the elastic recovery property of a PTFE/PU compound membrane through a co-stretching process was put forward. The experimental results show that the PTFE/PU membrane has great elastic recovery owing to PU. When the longitudinally stretching ratio of PTFE is 200%, the traverse stretching ratio is 850%, and the thickness of PU is 0.03 mm. When the longitudinally and traverse elastic recovery of PTFE/PU is 82.1% and 88.6%, respectively, the porosity is 78.0%, mean pore size is 0.382 μm, and the water vapour permeability is 9330 g/24 h m2. It has been used for the SARS protective clothing in China.