Patent GB-1070794-A (GB)
Title: Porous vinyl chlorite polymer structures and methods for making the same
IPC: C08J9/28
Filed: 1964-04-27
Abstract: A method of making compositions comprising forming with the aid of an emulsifier an aqueous suspension or emulsion of a vinyl chloride polymer plasticizer, and mixing vinyl chloride polymer in solid particulate form with said suspension or emulsion.  The resulting masses may be placed on thermally stable substrates and heated at a temperature of 130 DEG  to 200 DEG  C. sufficient to cause the water to evaporate without forming bubbles in the resulting structure and further heated above said temperature to form a final porous product comprising a monolithic plastic structure of coalesced and plasticized vinyl chloride polymer particles attached to each other at points of contact and separated by voids.  Specified polymers are polyvinyl chloride and copolymers of vinyl chloride with vinyl esters, olefins, acrylic esters and vinylidene halides. Specified plasticizers are dioctyl phthalate and tricresyl phosphate. Specified emulsifiers are ammonium and amine salts of fatty acids containing 12 to 18 carbon atoms, alkylaryl sulphonates and alkylaryl polyether alcohols. The compositions may also comprise stabilizers, antioxidants, fungicides, bactericides, dyes and pigments, and thickeners, e.g. acrylic acid polymers, hydrolysed polyvinylesters, cellulose ethers and acrylamide polymers.  The compositions may be applied to substrates, e.g. woven and non-woven fabrics of natural and synthetic fibres or wire, or paper, and cured to give porous coatings.  Alternatively the compositions may be cured in moulds to give porous unsupported films or other articles.  In examples, cotton sheeting is coated with emulsions comprising (I) polyvinyl chloride, dioctyl phthalate and ammonium oleate formed in situ, together with (II) an acrylic acid polymer, and the product cured at 180 DEG  C. to give substitutes for suede leather.ALSO:Substrates may be provided with a porous coating by a method which comprises forming with the aid of an emulsifier an aqueous suspension or emulsion of a vinyl chloride polymer plasticiser, adding thereto solid particulate vinyl chloride polymer, placing a mass of said suspension or dispersion on a thermally stable substrate and heating said mass to 130 to 200 DEG C. at a rate sufficient to evaporate the water without forming bubbles in the resulting structure and continuing the heating above said temperature to form a monolithic plastic coating of coalesced and plasticised vinyl chloride polymer particles attached to each other only at points of contact and separated by voids.  Specified substrates are paper, woven and non-woven fabrics, films and flexible metal sheets.  The substrates may be provided with a primer coating, e.g. a blend of vinyl chloride/vinyl acetate and styrene/acrylonitrile copolymers.  The coatings may be applied by roller, doctor blade or knife coaters, calendering or spraying equipment, and the heating be effected by hot air ovens, inducting heating devices or infra red heaters.  The compositions may also comprise stabilisers, fungicides, bactericides, dyes, pigments and thickeners e.g. water-soluble polymers such as acrylic acid polymers, partially hydrolyzed vinyl esters, polyvinyl alcohol, cellulose ethers, acrylamide polymers.  The products may be used as substitutes for suede leather, and for making seat covers and wearing apparel. In examples cotton sheeting is coating using a doctor blade coater with aqueous emulsions comprising (I) polyvinyl chloride, dioctyl phthalate and ammonium oleate together with (II) an acrylic polymer thickening agent, and the products cured at 180 DEG C to give substitutes for suede leather.