Vinyl acetate copolymer) from the Le Jian Compony The impervious performance of the composite geotechnical membrane depends on the impervious performance of plastic film. The plastic film should have strong corrosion resistance and good extensibility. The impervious film applied at home and abroad and the ECB used in the design of tunnel are mainly PVC；polyvinyl chloride, polyethylene, ethylene which are with a good performance of high?adaptability?to the?deformation. They are polymer chemistry flexible material with a small proportion. At present, it is with good frost resistance and low temperature.
