Abstract: Foamable glass composition suitable for making glass foam, which starts from water glass material and consisting essentially of 100 parts by weight of anhydrous modified sodium silicate and 0.5-4 parts by weight of CaCO.sub.3 as a foaming agent. A foam in the closed-cell form, which is light is in weight, and excellent water resistance, strength and heat resistance, is obtained, wherein CO.sub.2 in a gas existing in the cell is 50% by volume or more.

Abstract: An extremely fine acrylic polymer fiber pile fabric, which comprises a substratum fabric impregnated with an elastic polymer and having at least one pile layer formed by raising at least one surface of said fabric, is characterized in that said piles consist essentially of extremely fine independent acrylic polymer fibers, each of which has a denier of 0.8 or less and is provided with a number of amorphous scale-shaped protuberances formed on the peripheral surface thereof, and which has been produced by a wet spinning method from an acrylic polymer containing at least 80% by weight of acrylonitrile.

Abstract: Provided is dried porous membrane composed of acrylonitrile polymer walls separating predominantly interconnecting small-size pores. The membrane has surface layers integrated with a support layer to form a single continuous acrylonitrile polymer phase. At least one of the surface layers has pores of from 0.001 to 0.05 micron in average size, and the support layer has pores which are on the average larger than the pores in the surface layer or layers. The membrane has a porosity of from 20% to 70% by volume and a fragility of below 30. The membrane exhibits improved mechanical properties.

Abstract: Provided is dried porous membrane composed of acrylonitrile polymer walls separating predominantly interconnecting small-size pores. The membrane has surface layers integrated with a support layer to form a single continuous acrylonitrile polymer phase. At least one of the surface layers has pores of from 0.001 to 0.05 micron in average size, and the support layer has pores which are on the average larger than the pores in the surface layer or layers. The membrane has a porosity of from 20% to 70% by volume and a fragility of below 30. The membrane exhibits improved mechanical properties.

Abstract: An acrylonitrile polymer film is produced by the steps of:Extruding an acrylonitrile polymer solution in a tubular shape into a coagulation liquid bath while a coagulation liquid is introduced into and withdrawn from the inside of the extruded tubular-shaped film;Removing the solvent remaining in the coagulated tubular film, and;Biaxially stretching the tubular film containing 5 to 23% by weight of water based on the dry weight, at a temperature of 100.degree.-170.degree. C. at least twice its original length both in the longitudinal and transverse directions by a tubular stretching procedure.

Abstract: Modacrylic fibers having excellent flameproof property and retaining the superior whiteness, heat-stability, etc. of Acrylonitrile polymer fibers are produced from the polymers containing, as principal components, 50 percent by weight or more of acrylonitrile, 25 percent by weight of more of vinylidene chloride and 0.1 - 3 percent by weight of bis(2-chloroethyl) vinylphosphonate, and if necessary, as additional component, at least one copolymerizable ethylenically unsaturated compound.