| 摘要 |
PURPOSE:To obtain a membrane for sepn. of gases which is suited for sepn. of CO2, NO2, SO2, etc., has high mechanical strength and is chemically stable by forming a polyacetal resin to a film by a melt extrusion molding method or the like. CONSTITUTION:A polyacetal resin is obtd. as a homopolymer of formaldehyde or trioxane or as copolymer, and its melt index value is in a 0.5-50 range. When this is filmed, the film has about 650kg/cm<2> tensile break strength and when it is further biaxially oriented, it has about 2,000kg/m<2> strength, thus in both cases the strength is extremely high and the film is chemically stable. It is further possible to improve stability against decomposition by esterifying or etherifying the terminal groups. The coeffts. of sepn. of the polyacetal resin film for CO2, NO2 and SO2 are about 75-80, 3,000-3,500 and 3,900-4,200 respectively. |
