Patent GB-778423-A (GB)
Title: Carbamate monomers and homopolymers and co-polymers thereof
IPC: C08F18/22
Filed: 1954-01-31
Abstract: N-Substituted carbamic acid esters of the formula: <FORM:0778423/IV(a)/1> wherein R1 is hydrogen or a methyl group, R2 is an alkylene group of from 1 to 6 carbon atoms or a phenylene group, and R3 is hydrogen or an alkyl group of from 1 to 4 carbon atoms, alone, or admixed with one or more other monomers or polymers are polymerized in bulk, in aqueous or organic solvent solution or in aqueous or organic solvent suspension in the presence of a polymerization catalyst.  The carbalkoxy groups in the polymers and copolymers may be hydrolysed with alkalis to give products containing free carboxyl groups.  The latter compounds may be treated with ammonia to give products containing carboxylic amide groups, or may be acetalized by treatment with aldehydes such as paraldehyde, acetaldehyde and buryraldehyde.  The acetal derivatives may be hydrolysed to products containing free carboxyl groups or may be treated with ammonia to convert such free carboxyl groups as are usually present to amide groups.  The co-monomers may be vinyl esters e.g. vinyl acetate and butyrate, vinylidene chloride, vinyl halides, e.g. vinyl chloride, acrylates and methacrylates, e.g. methyl and ethyl acrylates and methacrylates styrene, substituted styrenes, acrylonitrile, acrylamides, e.g. N-isopropylacrylamide, N-octadecylcrotonamide, fumaramides, fumaramates, citraconamates, citraconamides, maleamates, maleamides and mixtures thereof. Polyvinyl alcohols having a long chain hydrocarbon group may be added as modifiers to the monomer or co-monomer mixtures prior to polymerization. Specified organic solvents are methanol and dioxane. Exemplified N-substituted allyl and methallyl carbamates are N-carbomethoxymethyl-, N - carbomethoxyethyl -, N - carbethoxymethyl -, N - carbethoxyethyl -, N-carboxymethyl -, N - carboxyethyl -, N - carboxyphenyl -, N - carbomethoxyphenyl - and N - carbethoxyphenyl - allyl and methallyl carbamates.  The catalyst may be benzoyl peroxide, hydrogen peroxide or potassium persulphate, the inorganic catalysts being preferably used in conjunction with sodium bisulphite.  The polymers and copolymers may be used for the preparation of dyeable fibres and photographic emulsions.  For the latter purpose the polymers and copolymers may be used above or in admixture with gelatin.ALSO:The invention comprises compounds of the formula: <FORM:0778423/IV(b)/1> wherein R1 is hydrogen or a methyl group, R2 is an alkylene group of from 1 to 6 carbon atoms or a phenylene group, and R3 is hydrogen or an alkyl group of from 1 to 4 carbon atoms.  The compounds are prepared by reacting an appropriate carbalkoxyalkyl or carbalkoxyphenyl isocyanate with allyl or methallyl alcohol and, if desired, hydrolysing the carbalkoxy group in the product to a free carboxy group.  The following N-substituted allyl and methallyl carbamates are exemplified: N-carbomethoxy methyl -, N - carbomethoxyethyl -, N - carbethoxymethyl -, N - carbothoxyethyl -, N-carboxymethyl -, N - carboxyethyl -, N - carboxyphenyl -, N - carbomethoxyphenyl - and N - carbethoxyphenyl - allyl and methallyl carbamates.