Abstract: The invention relates to a multi-layer, microporous polyolefin membrane having appropriate permeability, pin puncture strength, shutdown temperature, shutdown speed, meltdown temperature, and thickness uniformity. The invention also relates to a battery separator formed by such multi-layer, microporous membrane, and a battery comprising such a separator. Another aspect of the invention relates to a method for making the multi-layer, microporous polyolefin membrane, a method for making a battery using such a membrane as a separator, and a method for using such a battery.

Abstract: Disclosed herein is a polymer composition, its manufacture and use, said composition may comprise greater than about 90 mole % propylene monomer, and having a unique combination of properties, including one or more of the following: a heat of fusion of more than about 108 J/g, a melting point of 165° C. or higher, a Melt Flow Rate so low that it is essentially not measurable and a molecular weight of greater than about 1.5×106. Further disclosed herein are blends or mixtures of the present novel polymer composition and products, such as, for example, microporous film structures and the like comprising same.

Abstract: A layered microporous polymeric membrane includes a first blend region having a thickness T1, a third blend region having a thickness T3, and a second blend region located between the first and third blend regions and having a thickness T2, wherein [(T1?T2)/T1]?0.05 and [(T3?T2)/T3]?0.05.

Abstract: A microporous polyethylene membrane having well-balanced permeability, mechanical properties, heat shrinkage resistance, compression resistance, electrolytic solution absorbability, shutdown properties and meltdown properties, with an average pore diameter changing in a thickness direction is produced by melt-blending a polyethylene resin and a membrane-forming solvent to prepare a solution A having a resin concentration of 25 to 50% by mass and a solution B having a resin concentration of 10 to 30% by mass, the resin concentration in the solution A being higher than that in the solution B, (a) simultaneously extruding the resin solutions A and B through a die, cooling the resultant extrudate to provide a gel-like sheet in which the resin solutions A and B are laminated, and removing the membrane-forming solvent from the gel-like sheet, or (b) extruding the resin solutions A and B through separate dies, removing the membrane-forming solvent from the resultant gel-like sheets A and B to form microporous polyet

Abstract: A multi-layer, microporous polyethylene membrane having at least two layers, which comprises (a) a microporous polyethylene resin layer A comprising high-density polyethylene A having 0.2 or more terminal vinyl groups per 10,000 carbon atoms when measured by infrared spectroscopy, and (b) a microporous polyethylene resin layer B comprising high-density polyethylene B having less than 0.2 terminal vinyl groups per 10,000 carbon atoms when measured by infrared spectroscopy, has well-balanced permeability, mechanical strength, heat shrinkage resistance, shutdown properties, meltdown properties and oxidation resistance.

Abstract: Disclosed herein is multi-layer, microporous polyolefin membrane comprising a first porous layer comprising primarily a polyethylene, and a second porous layer comprising a polyethylene resin and polypropylene, the polypropylene having a weight-average molecular weight of 6×105 or more and a heat of fusion (measured by a differential scanning calorimeter) of 90 J/g or more, a fraction of the polypropylene having a molecular weight of 5×104 or less being 5% or less by mass.

Abstract: A microporous membrane includes polyolefin, and has a shutdown temperature ?133.0° C. and a self-discharge capacity ?110.0 mAh.