Modification of drawn film

The invention relates to stretching's polymer film, comprising: the (A) polymer or copolymer, and at least (B) one of average particle diameter of 0.1 to 15 μ the component, wherein the stretching, one or more of post treatment in the thermal-shrinkage film via (C). The component (B) average particle diameter of 0.1 to 15 μ m, preferably 0.5-8.0 μ m, preferably of 1.0 to 7.0 microns μ. The thermal-shrinkage film is used for producing a separating, wherein the seawater desalting, and other fuel cell and thermal-shrinkage film application.