GB861968A - Improvements relating to the compounding of rubbers and of synthetic resins - Google Patents

Abstract

Non-coherent compositions are made by distributing (see below) through the particles of a filler, a rubber in finely-divided form or a thermoplastic synthetic resin in finely-divided form, and also a liquid plasticizer for the rubber or resin, and subsequently heating the mixture to a temperature sufficient to cause at least a part of the plasticizer to be absorbed by the rubber or resin, and at least a part of the rubber or resin to be attached to the particles of the filler, without agglomeration of the mass. By "distributing" is meant intermingling the rubber or resin and plasticizer relatively lightly, e.g. in a paddle mixer, as opposed to intermixing by such forcible methods as grinding. The filler may be a fibrous filler such as wool, cotton, asbestos, glass wool, slag wool or regenerated cellulose, or a non-fibrous filler such as limestone, whiting, slate dust, brick dust, finely-divided nut-shells, sawdust or road-aggregates such as granite and quartz. The resin may be polyvinyl chloride, a copolymer of vinyl chloride with vinyl acetate, vinylidene chloride or ethyl acrylate, polyvinyl acetate, polyvinylidene chloride, or a terpolymer derived from the monomers of these polymers. The rubber may be a butadiene-acrylonitrile or butadienemethyl isopropenyl ketone copolymer, neoprene or a rubber-like chlorosulphonated polyethylene or polypropylene. The plasticizer may be dibutyl, dihexyl or dioctyl phthalate, or tricresyl or trichlorphenyl phosphate. The non-coherent compositions may be converted to coherent compositions by moulding or calendering to produce, e.g. floor tiles; they may be converted into surfacings for, e.g. airfield runways, roads and p railway-station platforms by mixing with tar and an aggregate, or into joint-filling materials by mixing with tar and a filler; they may be extruded to form, e.g. flooring blocks, or used as impregnating agents for felt and textile fabrics, as cements or as coatings for metals, wood, rubber and synthetic resins, particularly on pipes. Specifications 581,368, 737,022, 770,067, 827,847, 850,364 and 853,525 are referred to.