Abstract: Hydrophobic diaphragm material, such as crystalline, highly expanded microporous polytetrafluoroethylene film, may be prepared for installation in a chlor-alkali cell by a process involving the steps of (1) immersing the diaphragm in a solution of acetal-type nonionic surfactant in a suitable non-aqueous solvent, (2) rinsing the diaphragm in deionized water, (3) immersing the diaphragm in an aqueous solution containing an amount of acetal-type nonionic surfactant effective to promote wetting for a suitable period of time, and (4) immersing the diaphragm in a brine solution containing about 100 to 200 grams per liter of sodium chloride and an amount effective to promote wetting of an acetal-type nonionic surfactant for a suitable period of time, such as several hours. In some instances, it is also advantageous to subject the diaphragm while immersed in the solvent solution to the action of a vacuum, to release trapped air.

Abstract: To obtain nonionic surfactants having solubility and stability in relatively strong aqueous solution of caustic, salt or other electrolytes, corn starch or a similar source of glucose units is reacted with an alcohol containing up to about 4 carbon atoms to obtain a glycoside somewhat more lipophilic than the saccharide, and then the resulting glycoside is reacted with a hydrophobic oxirane-containing material such as a C.sub.6 to C.sub.18 epoxyalkane or a glycidyl ether having about the same number of carbon atoms.

Abstract: A method and apparatus are disclosed for the manufacture of foamed polystyrene particles of moderately great density, such as 3 to 25 lbs. per cubic foot (50 to 400 milligrams per cubic centimeter). Beads are fed by a constant-displacement auger to an expander vessel having the form of, in its lowest part, a cylinder with a vertical axis, and thereabove, of a frustrum of an inverted cone having a base angle of about 83.degree. to 70.degree.. Steam is supplied to the vessel in an appropriate, controlled manner. The vessel also contains stator bars, to break lumps and retard the rotation of the material in the vessel, and rotating bars, to provide the necessary agitation. Desirably, the equipment includes a discharge chute of adjustable location, to facilitate adjustment of the residence time and consequently of the density of the expanded beads being produced.

Abstract: By adding to the anolyte of an alkali-brine electrolysis cell of the kind that has a diaphragm of relatively hydrophobic material such as polytetrafluoroethylene, a small quantity of C.sub.8 to C.sub.14 alkyl glycoside, the wetting performance of said anolyte is much improved, and in some instances, good flow of anolyte through the diaphragm is readily re-established, without need for dismantling the cell to re-wet the diaphragm.

Abstract: In a diaphragm-type electrolytic cell for the production of chlorine and caustic alkali from alkali metal chloride solutions and having a plate type of coated metallic anode there are provided means for attaching the plate and detaching the plate anode from the cell base means without movement or destruction of either the cell base or the non-conductive corrosion resistant liner above the bus bar.

Abstract: By reacting a proper proportion of an alkylene oxide with methylene dianiline (MDA), there is obtained a curing agent or cross-linking agent useful in place of methylene-bis-orthochloro aniline (MOCA) for making polyurethane foams. The invention provides a solution to the problem of finding a substitute for MOCA, which has become suspected as a carcinogen.

Abstract: In an electrolytic cell for the production of halogen and caustic from an aqueous alkali metal halide solution containing anode and cathode compartments separated by a diaphragm an improved diaphragm is provided. The diaphragm is a porous sheet material made of a tetrafluoroethylene polymer having a low amorphous content and a micro-structure characterized by nodes interconnected by fibrils having a porosity of about 50 to 90 percent and a very tortuous path of interconnection. The improved diaphragm has an extremely long service life.