Patent GB-588660-A (GB)
Title: Improvements in the production of polymeric materials
IPC: C08F2/00
Filed: 1944-06-09
Abstract: Polymerizable compounds containing two CH2=C< groups per molecule are prepared by reacting one molecule of an allyl or an alpha and/or beta alkyl substituted allyl ester of an aliphatic hydroxy carboxylic acid, which acid contains one hydroxyl and one carboxyl group, with one molecule of phosgene or an anhydride or acid chloride of a dicarboxylic acid of not more than six carbon atoms, said chloride containing two -CO.C1 groups, so as to form a half ester or half ester acid chloride having the formula CH2 : CX1.CX2X3.O.CO.R.O.Z.Y, where X1, X2 and X3 may be hydrogen or alkyl radicals, R is a divalent aliphatic hydrocarbon radical, Z is an organic dibasic acid radical of not more than six carbon atoms and Y may be a hydroxyl or chloride radical, converting the half ester when formed to the half ester acid chloride suitably by means of thionyl chloride, and reacting the half ester acid chloride with a second molecule of one of said allyl or substituted allyl esters of hydroxy acids so as to form a tetraester.  When phosgene is employed as the dibasic acid chloride, then a base such as pyridine should be present in the reaction mixture used in the preparation of the tetraester.  The allyl esters of hydroxy acids may be prepared from alcohols such as allyl and methallyl alcohols and acids such as glycollic, lactic and hydracrylic acids, suitably, by reaction in an inert solvent such as benzene and removing water of esterification by azeotropic distillation; an esterification catalyst, for example, para-toluene sulphonic acid, may be present.  The other reactants specified include glutaric and adipic acid chlorides and succinic anhydride. The tetra-esters may be polymerized in one or more stages, preferably in the presence of a polymerization catalyst, especially in large amount such as 5 per cent by weight of benzoyl peroxide, and by raising the temperature as polymerization proceeds.  They may be copolymerized with other unsaturated organic compounds such as those containing one CH2=C< group per molecule, for example, methyl methacrylate, vinyl chloride, vinyl acetate or styrene, or in the presence of a material containing the group >C=C<, such as maleic anhydride; dyes, pigments and fibrous and mineral fillers may be present.  The tetra-esters may be cast and polymerized into resin articles; they may be used in coating compositions and may also be employed in the treatment of cloth or in the bonding together of fibrous or filamentary materials (see Group VIII).  In examples: (1) allyl glycollate, prepared by reacting allyl alcohol with glycollic acid, is reacted with liquid phosgene and the allyl glycollyl chloroformate so obtained reacted with a mole. of allyl glycollate in the presence of pyridine yielding di-(allyl glycollyl) carbonate, which is polymerized by heating with 5 per cent benzoyl peroxide; (2) in a similar manner, allyl glycollate is reacted with a mole. of succinic anhydride yielding allyl glycollyl hydrogen succinate which is reacted with thionyl chloride and the resulting half ester acid chloride treated with a mole. of allyl glycollate forming di-(allyl glycollyl) succinate; it is applied to glass cloth and polymerized; (3) allyl alcohol and lactic acid are reacted together and resulting allyl lactate treated as in (2) to yield allyl lactyl allyl glycollyl succinate; (4) a mixture of the ester of (1) above and vinyl chloride; and (5) a mixture of the ester of (2) above and maleic anhydride, are polymerized by heating in presence of benzoyl peroxide. Specification 574,606, as open to public inspection, is referred to.  The Provisional Specification describes tetra-esters of the form CH2=CX.CH2.O. CO.R1.O.Z.O.R11.CO.O.CH2.CX=CH2, where X may be hydrogen, a halide or monovalent hydrocarbon or substituted hydrocarbon radical, R1 and R11 are divalent hydrocarbon or substituted hydrocarbon radicals and Z is a dibasic organic acid radical prepared by reacting allyl esters of hydroxy carboxylic acids with the chlorides of dibasic acids with or without the presence of a base, or with the anhydrides of the dibasic acids with or without the presence of an azeotrope-forming liquid.  In addition to example (1) above, further examples illustrate the preparation of (1) di-(allyl glycollyl) succinate by reacting succinic acid anhydride with excess allyl glycollate, and (2) di-(allyl glycollyl) adipate by reacting adipyl chloride (1 mol.) with allyl glycollate (2 mols.).