Patent GB-1002664-A (GB)
Title: Unsaturated esters and polymers thereof
Inventor: GIBB ALEXANDER RAMSEY MAUND
IPC: C08G2/26
Filed: 1963-07-23
Abstract: Polymers and copolymers of unsaturated esters of formula <FORM:1002664/C3/1> where R1 is a monovalent radical with at least one carbon-carbon double bond, R2 is as R1, or may additionally be a monovalent aliphatic, cycloaliphatic, arylaliphatic or aromatic hydrocarbon radical, or monovalent heterocyclic radical or a substituted derivative thereof, R3 may be as R2 or additionally R2-O-, hydrogen or a divalent chain forming a cyclic hydrocarbon or heterocyclic ring with the carbon atom, T is an organic radical containing two or more carbon atoms and having a valency of 2Z, the two oxygen atoms being attached to different carbon atoms of T, Z is a positive integer and X is either one or two, and n is an integer greater than 1, specifically polyoxymethylene acetate methacrylate, polydioxolane diacrylate, diacrylate of a dioxolane/trioxane copolymer, pentaerythritol dicrotonate di-(oxymethyl crotonate), and poly-(4-methyldioxolane) dicrotonate are prepared using free radical catalysts such as benzoyl peroxide and azodiisobutyronitrile or U.V. radiation. Copolymers with styrene, methyl methacrylate or vinyl acetate. The esters are prepared (see Division C2) by reacting an unsaturated carboxylic acid anhydride of formula <FORM:1002664/C3/2> with a cyclic acetal, ketal or cyclic orthoester <FORM:1002664/C3/3> in presence of acidic or Friedel-Crafts catalyst. Examples describe the preparation of the specific esters above and their polymerization and copolymerization with styrene and vinyl acetate.ALSO:Unsaturated polymerizable esters of formula <FORM:1002664/C2/1> where R1 is a monovalent radical with at least one carbon-carbon double bond, R2 is as R1 or may additionally be a monovalent aliphatic, cyclo-aliphatic, aryl aliphatic or aromatic hydrocarbon radical, or monovalent, heterocyclic radical or a substituted derivative thereof, R3 may be as R2 or additionally R2-O-, hydrogen or a divalent chain forming a cyclic hydrocarbon or heterocyclic ring with the carbon atom, T is an organic radical containing two or more carbon atoms and having a valency 2Z, the two oxygen atoms being attached to different carbon atoms of T, z is a positive integer and x is either one or two, and n is an integer greater than 1, specifically polyoxymethylene acetate methacrylate, polydioxolane diacylate, diacylate of a dioxolane/trioxane copolymer, pentaerythritol dicrotonate di-(oxymethylcrotonate) and poly-(4-methyl dioxolane) dicrotonate, are prepared by reacting an unsaturated carboxylic acid anhydride <FORM:1002664/C2/2> with a cyclic acetal, a cyclic ketal, or a cyclic orthoester of formula <FORM:1002664/C2/3> in the presence of an acidic or Friedel-Crafts catalyst. Anhydrides of acrylic, methacrylic, crotonic and mixed linseed oil fatty acids, and acetyl methacrylate are specified and the cyclic acetal, ketal or ortho-ester may be trioxane, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 4-chloromethyl - 1,3 - dioxolane, 2 - methyl - 1,3 - dioxolane, 2 - ethoxy - 1,3 - dioxolane, 2 - ethyl - 1,3-dioxolane, ethylene glycol cyclohexanone ketal, neopentyl glycol cyclic formal, trimethylolethane monoacetate monoformal, pentaerythritol dichloride monoformal, 1,3,5-trioxepane, 1.3.6,trioxocane, pentaerythritol diformal, trimethylol propane sesquiformal, sorbitol triformal, polyvinyl formal, polyvinyl butyral or mixtures thereof.  Catalysts mentioned are perchloric, sulphuric acids, boron trifluoride, boron trifluoride etherate, triethyl oxonium fluoroborate, ferric, stannic or aluminium chloride, a stannic bromide, and a base such as triethylamine or sodium acetate may be used to neutralize them after completion of the reaction. The products may be polymerized with free radical catalysts or by treatment with ultra-violet radiation and copolymerized for example with styrene, methyl methacrylate or vinyl acetate.  Examples describe the reaction of acetyl methacrylate with trioxane to yield polyoxymethylene acetate methacrylate; acrylic anhydride and dioxolane to yield a polydioxolane diacrylate; acrylic anhydride and dioxolane/trioxolane; crotonic anhydride and pentaerythritol diformal to yield pentaerythritol dicrotonate di-(oxymethylcrotonate) (CH3CH= CHCO2CH2)2C(CH2OCH2O2C.CH = CH CH3)2; crotonic anhydride and pentaerythritol bis-(acrolein acetal); and crotonic anhydride and 4-methyldioxalane to yield a poly-(4-methyl-dioxolane) dicrotonate.