Polyvinyl chloride stabiliser combinations and polyvinyl chloride resins stabilised thereby

摘要

Polyvinyl chloride resins are stabilized with a composition comprising (1) a polyol where R is hydrogen or an alkyl or alkoxy group; the alkyl or alkoxy group may include additional substituents, e.g. hydroxyl or alkoxy groups or both together and the R radical, when not hydrogen, has from 1 to 30 carbon atoms, (2) a hydrocarbon-substituted phenol having at least one phenolic hydroxyl group and from 1 to 30 carbon atoms per phenolic hydroxyl group and (3) a metal salt stabilizer which is a salt of a polyvalent metal and an organic monocarboxylic acid having from 6 to 18 carbon atoms and which contains no nitrogen atoms. Typical polyols include dipentaerythritol, trimethylolpropane, trimethylolethane and trimethylolbutane. The phenol contains one or more phenolic hydroxyl groups and may contain one or more phenolic nuclei and the phenolic nucleus may have an oxy or thioether substituent. In addition the phenol will have one or a plurality of alkyl, aryl or cycloalkyl substituents or a second ring condensed therewith as in the naphthols, having one or more carbon atoms, up to the total number of carbon atoms per phenolic hydroxyl group. The phenols may have from one to five substituent radicals per phenolic nucleus. Lists of suitable phenols are given. The acid component of the metal salt stabilizer may be aliphatic, aromatic, alicyclic or heterocyclic monocarboxylic acids having oxygen in the heterocyclic ring. The acids may be substituted with halogen, sulphur and hydroxyl groups and the metal component is preferably an alkaline earth metal e.g. magnesium, barium, strontium, calcium, or zinc, cadmium, lead or tin. Lists of acids are given. The stabilizer composition of the invention may have in addition other stabilizers normally used with polyvinyl chloride resins. Epoxy compounds having from 10 to 150 carbon atoms may also be added. A plasticizer, e.g. dioctyl phthalate, dioctyl sebacate, tricresyl phosphate and epoxy higher esters having from 22 to 150 carbon atoms, and usually not more than 1,5% of a parting agent, e.g. a higher aliphatic acid having from 12 to 24 carbon atoms or mineral lubricating oils, polyvinyl stearate, polyethylene or paraffin wax are usually added. The term "polyvinyl chloride resins" includes homopolymers of vinyl chloride, copolymers of vinyl chloride with vinyl acetate, vinylidene chloride, maleic or fumaric acid or styrene and also mixtures of polyvinyl chloride with a minor proportion of other synthetic resins, e.g. chlorinated polyethylene or a copolymer of acrylonitrile, butadiene and styrene. In the examples the stabilizer compositions used are (a) barium laurate, cadmium laurate, trimethylol propane and p-nonyl phenol, (b) cadmium and zinc stearate, 2,6-ditertiary-butyl-p-cresol and trimethylol ethane, (c) cadmium t-butyl benzoate, para-tertiary-butyl phenol and trimethylol ethane, (d) barium laurate, cadmium benzoate, bisphenol A and dipentaerythritol, the resins in each case being polyvinyl chloride homopolymer or a copolymer of 87% vinyl chloride and 13% vinyl acetate. Specification 752,053 is referred to.