GB655873A - Improvements in or relating to liquid adhesive cement compositions, film material formed from said cement compositions, and method of making said liquid adhesive cement compositions - Google Patents

Abstract

A liquid adhesive composition capable of forming a tough heat-resistant bond to smooth metal surfaces comprises a heat-reactive phenolaldehyde resin and a rubbery butadieneacrylonitrile copolymer in a weight ratio of from 1 : 2 to 10 : 1, respectively, in a volatile liquid vehicle, the phenolic resin being soluble in methyl ethyl ketone and insoluble in benzene. The heat-reactive resins may be prepared from phenol, o- and m-cresols, m-ethyl phenol, sym. xylenol, resorcinol or p,p1-dihydroxydiphenyl and acetaldehyde, formaldehyde, paraformaldehyde, hexamethylene tetramine or propionaldehyde. Mixtures of phenols and/or of aldehydes may be used. An acid catalyst is preferably used initially but the subsequent reaction to the required stage requires an alkaline catalyst. The copolymers are preferably those having butadiene-acrylonitrile ratios of 50 : 50 to 80 : 20. Minor amounts of other polymerizable monomers such as styrene may be used in their preparation. Specified solvents are methyl ethyl and isobutyl ketones and ethylene dichloride. The phenolic resin may be formed in situ, particularly with a highly reactive phenol such as resorcinol, by adding an aqueous solution of formaldehyde to a solution of the phenol and copolymer and heating after applying the solution to a surface. Pigments, fillers, softeners and resins may be added and carbon black, abrasive grit and ground cork are specified. The compositions, which may be used in the form of a pre-dried and partially cured film, may be used for bonding wood, fabric, synthetic polymers and abrasive grits to metals and wood to wood or to fabric, leather to fabric and resins to leather; and, coated on thin fibrous sheets, as wrapping material, barrier films and backings. A composition also described which is bonded by the above compositions to aluminium comprises a butadiene-acrylonitrile copolymer, a phenolic resin and magnesium salicylate. Reference has been directed by the Comptroller to Specifications 569,666, 580,333, 610,345 and 616,336.ALSO:A synthetic rubber coating is adhered to sheet aluminium by a cement comprising a rubbery butadiene-acrylonitrile copolymer and a phenol-aldehyde resin in a volatile liquid vehicle. In the example, 130 parts of a phenol-acetaldehyde-formaldehyde resin and 100 parts of the material known under the Registered Trade Mark "Hycar OR-15" are dissolved in methyl isobutyl ketone and applied to the metal. After evaporation of the solvent, a heavy dough of a rubbery butadiene-acrylonitrile copolymer modified by a phenolic resin and magnesium salicylate is applied and dried and the composite article is heated, e.g. for 15 minutes at 150 DEG F. Other phenolic resins which are insoluble in benzene and soluble in methyl ethyl ketone may be used in the cement. Reference has been directed by the Comptroller to Specifications 569,666, 580,333, [Group IV], 610,345 and 616,336.