Abstract:
Multi-layer, microporous polyolefin sheet materials are provided. The sheet materials comprise at least two microporous polyolefin layers, the layers being autogenously bonded and having substantially the same porosity as prior to bonding.
Abstract:
A pseudo-gel comprising a suitable solvent in an amount of 99 to 90 percent by weight and an ultra-high-molecular-weight polyethylene in an amount of 1 to 10 percent by weight, said polyethylene being a semicrystalline network with adjustable crystalline morphology comprising randomly dispersed and oriented chain-folded single crystals, stacks of single crystals, spherulite crystals, and extended-chain shish-kebab-type of fibrils with lengths up to a few millimeters and widths up to 20 .mu.m. Also, the semicrystalline ultra-high molecular-weight polyethylene obtained by removal of said solvent from the pseudo-gel. Further, a method for making the pseudo-gel and the ultra-high-molecular-weight polyethylene product.
Abstract:
The invention relates to a process producing porous powdery polymer particles. A homogeneous mixture having two components minimum, one a meltable polymer, the other fluid inert to the polymer, both forming a system having a range of complete miscibility and a miscibility gap are introduced to a bed of solid-substance particles, then cooling the mixture to below solidification of the polymer and comminuting the obtained cake-like mass. The polymer is separated then from the inert fluid and solid-like substance particles.
Abstract:
This invention is directed to a microporous film comprising a 40 to 90 volume percent polyolefin having a number average molecular weight of 15,000 or more and a weight average molecular weight of less than 300,000 and a 10 to 60 volume percent inorganic filler and having a void space rate or porosity of 30 to 75 volume percent based on the volume of the film. The microporous film of such specific composition and structure has a desired wettability and a much reduced electrical resistance. Said resistance being as low as 0.0006 .OMEGA.dm.sup.2 /sheet. Said film has sufficient flexibility and mechanical strength to make it useful in wide variety of applications, especially as separators in batteries or electrolytical apparatuses etc. Such microporous material is prepared by: (a) blending a specified polyolefin, an inorganic filler and an organic liquid in amounts of 10 to 60 volume percent, 6 to 35 volume percent and 30 to 75 volume percent, respectively, based on the total volume of the blend, the amount of the polyolefin being 2/3 to 9 times the amount of the inorganic filler; (b) molding the blend to form a film; and (c) extracting said organic liquid from the molded film.
Abstract:
Novel microporous polymers in forms ranging from films to blocks and intricate shapes from synthetic thermoplastic polymers, such as, olefinic, condensation, and oxidation polymers, are disclosed. In one embodiment the microporous polymers are characterized by a relatively homogeneous, three-dimensional cellular structure having cells connected by pores of smaller dimension. Also disclosed is a process for making microporous polymers from such thermoplastic polymers by heating a mixture of the polymer and a compatible liquid to form a homogeneous solution, cooling said solution under non-equilibrium thermodynamic conditions to initiate liquid-liquid phase separation, and continuing said cooling until the mixture achieves substantial handling strength. Also disclosed are microporous polymer products which contain relatively large amounts of functionally useful liquids and behave as solids.
Abstract:
Microporous styrene polymers are provided having randomly interconnected open network of irregularly shaped pores whose walls consist of cohered spherical particles of the polymer. These microporous styrene polymers are produced by mixing styrene polymer latex with a water-soluble ether, casting, molding, or impregnating the resulting mixture into a fibrous material, heating same to a temperature of from about 80.degree. C to about 120.degree. C and removing the ether.
Abstract:
A method of making a porous polymeric material comprising a plurality of interconnected cells, comprising mixing together 100 parts of a liquid prepolymer, at least 40 parts of an inert organic liquid and 1.5 to 15 parts of an emulsifier to form a stable emulsion of dispersed liquid prepolymer in the organic liquid, heating the emulsion to at least 90* C in the presence of a cross-linking agent to form a porous polymeric material with a plurality of interconnected cells filled with the organic liquid, and extracting the organic liquid from the cells.
Abstract:
The present invention provides porous particles uniform in shape and having through holes that are not closed. The porous particles according to the present invention are porous particles having a substantially spherical shape. Each of the porous particles has an interconnected pore structure in which through holes provided inside the porous particle communicate with each other, and ends of the through holes are open toward an outside of the porous particle.
Abstract:
The present disclosure provides a method of producing a aerogel comprising of reacting first monomer with a second monomer in a reaction solvent to form a composition comprising a precursor polymer; forming a gel; conducting a solvent exchange process on the gel such that the resulting gel comprises an exchange solvent that has a freezing point; cooling the gel to a temperature below the freezing point of the exchange solvent; and subjecting the cooled gel to vacuum conditions to obtain the aerogel.
Abstract:
A vinyl chloride-based copolymer porous body contains a vinyl chloride-based copolymer as the main component. The vinyl chloride-based copolymer porous body has continuous pores having a pore size of 0.1 to 40 μm, the pores have a skeletal diameter of 0.1 to 20 μm, and the vinyl chloride-based copolymer has a thickness of 1 mm or more. Such a vinyl chloride-based copolymer porous body can be produced by a production method including the steps of: heating and dissolving the vinyl chloride-based copolymer in a solvent to obtain a vinyl chloride-based copolymer solution; cooling the vinyl chloride-based copolymer solution to obtain a precipitated product; and separating and drying the product to obtain a porous body containing the vinyl chloride-based copolymer as the main component.