Patent GB-806926-A (GB)
Title: Improvements in or relating to moulding compositions
Inventor: JR JAMES W HYLAND
IPC: C08G63/682
Filed: 1956-02-17
Abstract: Resin-coated kaolin particles are obtained by adding kaolin to a reaction mixture of melamine, formalin, and water, heated to 80 DEG C. and adjusted in pH to 6-7 by lactic acid, cooled and diluted.  The mass is mixed, dried at 160 DEG  F., and ground into chunks, further dried at 300 DEG  F., ground in a rotary knife mill and finally ball-milled to finely-pulverized material. Specifications 649,955 and 721,341, [both in Group IV (a)], are referred to.ALSO:A moulding composition comprises a mixture of from 50 to 85 per cent of filler, and from 15 to 50 per cent of a mixture of (a) 9 parts by weight of a solid amorphous polymerizable unsaturated alkyd with a viscosity of from 0.9 to 5.0 poises and an acid number of from 10 to 35 formed from a polycarboxylic acid and a polyhydric alcohol, in which from 4 to 40 per cent of the polycarboxylic acid radicals are chlorosubstituted phthalic acid radicals, and from 60 to 90 per cent are dicarboxy alkene radicals containing from 4 to 5 carbon atoms, having their carboxy residues attached to adjacent carbon atoms; (b) at least one part by weight of dialkyl phthalate; and (c) an organic peroxide polymerization catalyst.  The maximum weight of diallyl phthalate present is not more than <FORM:0806926/IV (a)/1> per cent of the total weight of (a) and (b), where n is the average number of chlorine atoms per chloro-substituted phthalic acid radical in the unsaturated alkyd, and X the amount of chlorine in such radicals expressed as a percentage based on the weight of unsaturated alkyd. The composition is free from antimony oxide but in a modification up to 1 per cent of antimony oxide may be present.  The unsaturated alkyd may be prepared from 3-, or 4-chlorophthalic, 3,6- or 4,5-dichlorophthalic, 3,4,6-trichlorophthalic, tetrachlorophthalic, tetrachloroisophthalic and tetrachloroterephthalic acids or their anhydrides together with maleic, fumaric, itaconic, citraconic, or mesaconic acids or anhydrides, optionally with additional acids such as oxalic, malonic, to sebacic acids, benzene, naphthalene or cyclohexane dicarboxylic acids, diglycolic, dilactic or rescorcinol diacetic acids, reacted with one or more polyhydric alcohols such as glycerol, pentaerythritol, polymethylene glycols, propylene, butylene, polyethylene glycols, pentadiol-2,4, dipropylene glycol, butandiol-2,3, monoformin, monoacetin, monomethylin, monoethylin, dihydroxybutane to decane, or ethers of allyl or methallyl alcohol with glycerol, pentaglycerol, pentaerythritol, butantetrol-1,2,3,4 and butantriol-1,2,3 or a monomethyl or monoisobutyl ether of pentaerythritol or butantetrol-1,2,3,4 together with an optional monohydric alcohol or monobasic acid, in the presence of an acid catalyst and an inhibiting agent such as hydroquinone, pyrogallol, tannic acid, aniline or phenylene diamine in an inert atmosphere. The fillers may be organic such as cellulose, e.g. a -cellulose, shredded paper or chopped cloth, and/or inorganic, such as kaolin, glass fibres or silicates, and they may be resin-coated, e.g. with a melamine-formaldehyde thermosetting resin.  Compounds such as the chlorides, bromides, nitrates, sulphites, hydroxides of alkali or alkaline earth metals, and bases such as the oxides, hydroxides, borates, carbonates and alcoholates of Group II metals, e.g. zinc oxide and barium carbonate may also be included. Catalysts mentioned are benzoyl, succinyl, acetyl, toluyl, p-bromobenzoyl, anisoyl, chloracetyl, acetyl-benzoyl, and furoyl peroxides, t.-butyl benzoate, di-t-butyl perphthalate, peracetic and perbenzoic acids and the composition is prepared under conditions such that no reaction takes place between the ingredients, by mixing or milling at a temperature below 180 DEG  C., with or without a solvent such as methylene chloride, acetone or methyl "Cellosolve" (Registered Trade Mark), and sheeting or granulating the product.  In examples: (1) and (2) unsaturated alkyds of a mixture of ethylene and propylene glycol with maleic and dichlorophthalic anhydrides with hydroquinone inhibitor, are mixed with diallyl phthalate, anthophyllite fibres, kaolin, zinc oxide and zinc stearate and a benzoyl peroxide catalyst "Luperro" (Registered Trade Mark), sheeted, and granulated; (3) as (1) with the addition of phthalic anhydride; and (4) an unsaturated alkyd of ethylene and propylene glycol and pentanediol-2,4 or 2-ethylhexandiol-2,3 and maleic and tetrachlorophthalic anhydrides, and diallyl phthalate, mixed with benzoyl peroxide catalyst, melamine-formaldehyde resin-coated kaolin particles, anthophyllite fibres, barium carbonate and zinc stearate.  The products are storage stable and are sheeted and granulated and may be moulded to give products of improved water absorption characteristics and electrical properties, such as insulation.  Specifications 649,955 and 721,341 are referred to.