GB470503A - Esters of methacrylic acid and their manufacture - Google Patents

Abstract

Methacrylic acid esters of aliphatic polyhydric alcohols in which all but one of the hydroxyl groups have been replaced by substituent groups, other than amino groups, are manufactured by reacting such alcohols with a lower ester of methacrylic acid in the presence of an ester-interchange catalyst, or with a methacrylyl halide. Suitable starting materials are: glycerols or mono-, di-, tri-, tetra-, penta- and higher alkylene glycols in which all but one of the hydroxyl groups have been replaced by a substituent, such as an ester, ether, halide, nitrate or cyanide, e.g. ethylene and propylene glycol monomethyl, monoethyl, monopropyl and higher ethers, higher substituted methylene glycols such as tetramethylene, pentamethylene and decamethylene glycol monoalkyl ethers, dialkyl glycerols such as the dimethyl, diethyl and methyl ethyl ethers, and the corresponding esters, halides, nitrates and cyanides, such as ethylene, diethylene and propylene glycol monoacylates, glycol mononitrate, and ethylene glycol monocyanide. In examples: (1) sodium is dissolved in ethylene glycol monoethyl ether and the alcoholate is heated with methyl methacrylate in the presence of hydroquinone, producing ethylene glycol monoethyl ether methacrylate; (2) ethylene glycol monomethyl ether is heated with methyl methacrylate, benzene, hydroquinone and sulphuric acid, yielding ethylene glycol monomethyl ether methacrylate; (3) diethylene glycol monobutyl ether is heated with methyl methacrylate, sulphuric acid and hydroquinone to produce diethylene glycol monobutyl ether methacrylate; (4) ethylene chlorhydrin is reacted as in (2) to produce b -chlorethyl methacrylate. Polymerization products are manufactured by polymerizing the esters described above by the processes described in Specifications 465,789 and 467,900, if desired with the addition of the modifying agents enumerated therein. The polymers, interpolymers, mixed polymers and syrupy partial polymerization products may be employed for the purposes set out in the said Specifications. In examples: (5) ethylene glycol monoethyl ether methacrylate is heated in aqueous methanol solution with benzoyl peroxide; (6) ethylene glycol monomethyl ether methacrylate is similarly polymerized and the product is moulded to a disc; (7) ethylene glycol monomethyl ether methacrylate is heated with benzoyl peroxide; (8) diethylene glycol monobutyl ether methacrylate is polymerized as in (5); (9) b -chlorethyl methacrylate is similarly polymerized, and the product is moulded to a disc. Specification 15271/14, [Class 2 (iii)], also is referred to.