FIELD: process engineering.
SUBSTANCE: set of invention relates to production of producing multilayer microporous polyolefin membrane comprises microporous polypropylene layer and that of polyethylene resin. Proposed method comprises simultaneous extrusion of melt including mix of polypropylene resin and membrane-forming agent and melt including mix of polyethylene resin and membrane-forming solvent via spinneret to produce laminated extrudate. Obtained laminated extrudate is cooled to produce gel laminated sheet to be stretched at -20°C or higher to below +90°C. Re-stretching is performed at 90-135°C and membrane-forming solvent is removed from stretched gel laminated sheet. Note here that polyethylene resin is used to produce said membrane containing polyethylene with super high molecular weight and mean weighed molecular weight distribution of 5×105 to 15×106. Note also that stretching of laminated sheet is carried out at ot -20 to +70°C. Proposed method may be carried out by extrusion of melt including mix of polypropylene resin and membrane-forming agent and melt including mix of polyethylene resin and membrane-forming solvent via separate spinnerets. Note also that membrane-forming solvent is removed from each stretched sheet and, thereafter, lamination of produced microporous polypropylene and polyethylene membranes is carried out. Note that stretching of both polypropylene and gel sheet from polyethylene resin may be effected at ot -20 to +70°C.
EFFECT: balance permeability, mechanical strength and resistance to thermosetting.
4 cl, 6 ex, 2 tbl
