Patent GB-772848-A (GB)
Title: Freeze-stable aqueous emulsions of natural or synthetic rubber adhesives
IPC: C08L21/02
Filed: 1954-10-26
Abstract: An adhesive and coating composition comprises an aqueous emulsion which is stable when subjected to alternate freezing and thawing containing synthetic rubber, a tackifier, and a minor proportion, e.g. between 5 and 25 per cent by weight of the non-volatile components of the emulsion, of an alkali-neutralized acidic vegetable pitch.  The composition is preferably made by preparing a "water-in-oil" type of dispersion of the ingredients, and inverting it into an "oil-in-water" type.  In one example 1200 lb. paving asphalt, 300 lb. tall oil pitch, and 50 lb. coumarone-indene resin are blended in a heated mixer.  The batch is then cooled and 300 lb. polychloroprene latex and a little 50 per cent potassium hydroxide solution and water added. 208 lb. 15 per cent potassium caseinate solution are then mixed in, and the emulsion inverted by adding 50 per cent potassium hydroxide solution and water so that the total amounts of these two ingredients incorporated in the mix are 60 lb. and 1325 lb., respectively.  The potassium caseinate solution may be omitted.ALSO:An adhesive and coating composition comprises an aqueous emulsion which is stable when subjected to alternate freezing and thawing and contains natural or synthetic rubber, a tackifier, and a minor proportion of an alkali-neutralized acidic vegetable pitch. The amount of pitch is preferably between about 5 and 25 per cent by weight of the non volatile components of the emulsion.  The composition is preferably made by preparing a "water-in-oil" type of dispersion of the ingredients, and inverting it into an "oil-in-water" type.  In one example 1,200 lbs paving asphalt, 300 lbs tall oil pitch, and 50 lbs coumarane-indene resin are blended in a heated mixer.  The batch is then cooled and 300 lbs polychloroprene latex and a little 50 per cent potassium hydroxide solution and water added.  208 lbs 15 per cent potassium caseinate solution are then mixed in, and the emulsion inverted by adding 50 per cent potassium hydroxide solution and water so that the total amounts of these two ingredients incorporated in the mix are 60 lbs and 1,325 lbs respectively.  The potassium caseinate solution may be omitted.ALSO:An adhesive and coating composition comprises an aqueous emulsion which is stable when subjected to alternate freezing and thawing and contains natural or synthetic rubber, a tackifier, and a minor proportion of an alkali-neutralized acidic vegetable pitch. The amount of pitch is preferably between about 5 and 25 per cent by weight of the non-volatile components of the emulsion. The composition is preferably made by preparing a "water-in-oil" type of dispersion of the ingredients, and converting it into an "oil-in-water" type.  In an example a uniform mixture comprising 678 lbs. milled black reclaim rubber 750 lbs. blown asphalt, and 116,5 lbs. heat-treated wood rosin is prepared in a steam heated mixer, and 264 lbs. vegetable pitch and 102 lbs. clay added thereto, the resultant mix being cooled.  To the mix is then added 37 lbs. ice, 115,8 lbs. 50 per cent caustic potash solution, 150 lbs. 25 per cent potassium caseinate solution if desired, and additional ice and water to make a total of 738 lbs.  Foam retardant, e.g. 5,4 lbs. of 25 per cent solution of methyl silicone in xylol is also added.  The product is particularly adapted for use as a floor tile cement.  A further composition is described comprising asphalt, tall oil pitch, coumarone-indene resin, polychloroprene latex, caustic potash, and potassium caseinate.