GB593475A - Pimelic acid esters and polymers - Google Patents

Abstract

Polymerizable diallyl pimelates having the general formula <FORM:0593475/IV/1> wherein R is the methyl radical, R1 is an aliphatic, aromatic-substituted aliphatic or alicyclic radical and X is hydrogen, halogen or an alkyl radical, are prepared by heating the parent gamma di-substituted pimelic acid, the corresponding dinitrile or an alkyl ester of said acid with allyl or 2-halo or 2-alkyl allyl alcohol in the presence of an esterification or ester-exchange catalyst, the ester used being of an alkanol having a lower boiling point than that of the selected allyl alcohol. The esterexchange method may be carried out by heating the ester and selected allyl alcohol in the presence of a mineral acid or aromatic sulphonic acid and distilling off the alkyl alcohol as it is formed. The pimelates, which are stated to be novel, include those in which R1 represents a methyl, ethyl, isopropyl, butyl, amyl or isopropenyl radical and X represents hydrogen, chlorine, bromine, methyl, ethyl, propyl or butyl. The parent substituted pimelic acids may be prepared by reacting an appropriate methyl ketone containing one methylene group adjacent the carbonyl group with acrylonitrile and converting the resulting dinitrile to the dicarboxylic acid. Thus, methyl ethyl ketone in t-butyl alcohol is reacted with a methanol solution of potassium hydroxide and the gamma-acetyl-gamma-methyl pimelonitrile so obtained is hydrolysed with aqueous caustic soda yielding the corresponding pimelic acid on acidification; methyl propyl ketone, methyl n-butyl ketone, methyl n-amyl ketone and methyl n-hexyl ketone may be reacted likewise. The esters may be polymerized or copolymerized at temperatures between room temperature and 100 DEG C. suitably with the aid of ultra-violet light or a polymerization catalyst such as an organic peroxide or hydroperoxide or sodium peroxide or perborate; an inert solvent, for example dioxane, benzene or toluene, may be present. Two or more of these esters may be copolymerized; they may also be interpolymerized with other monomers, for example, styrene, acrylonitrile, methacrylonitrile, methyl-, ethyl- and butyl-methacrylates, butyl acrylate, vinyl chloride and vinylidene chloride. The pimelates may be polymerized with a mixture of vinyl and vinylidene chlorides in aqueous emulsion. Laminated polymers with paper and cloth may be prepared (see Group VIII). Examples describe the polymerization of diallyl gamma-acetyl-gamma-methyl pimelate. A sample has been furnished under Sect. 2 (5) of diallyl gamma-acetyl-gamma-methyl pimelate prepared by refluxing allyl alcohol with gamma-acetyl-gamma-methyl pimelic acid in benzene in the presence of sulphuric acid. The Specification as open to inspection under Sect. 91 also comprises the preparation and polymerization of pimelates of the above general formula wherein R may be an aromatic radical and R1 an organic substituent, thus, in addition to the above examples, R may represent the phenyl radical; R1 may represent the benzyl or cyclohexyl radicals. This subject-matter does not appear in the Specification as accepted.