The invention relates to a separating membrane for separating a sulfur dioxide gas. Particularly, the invention discloses a polyvinylidene fluoride-polyol block copolymer gas separation membrane for separating sulfur dioxide. In the polyvinylidene fluoride-polyol block copolymer gas separation membrane, the molecular weight of a polyvinylidene fluoride block is at least 1000, the total quantity ofthe polyvinylidene fluoride block occupying the block copolymer is at least 50 percent, the molecular weight of polyol is at least 100, and the total quantity of the polyol occupying the block copolymer is at least 1 percent. The prepared gas separating membrane can be used for separating the mixed gas containing the sulfur dioxide gas.
修改评论