Patent GB-786119-A (GB)
Title: Improvements in or relating to polymers and their uses
IPC: C08F2/46
Filed: 1955-09-26
Abstract: Examples disclose the preparation of (1) m-methacrylamidobenzaldehyde ethylene glycol acetal by treating at a pH of 7-9 and 0-5 DEG  C. an acetone solution of m-aminobenzaldehyde ethylene glycol acetal with an anhydrous dioxane solution of methacrylyl chloride, (2) p-vinylbenzaldehyde ethylene glycol acetal by adding p-(2-bromoethyl) benzaldehyde ethylene glycol acetal to a solution of potassium hydroxide in ethanol, (3) m-(p-vinylbenzenesulphonamido) benzaldehyde ethylene glycol acetal by adding, to a solution of potassium hydroxide in ethanol, m - {p - (2 - bromoethyl) - benzenesulphonamido} benzaldehyde-ethylene glycol acetal prepared by adding the sulphonyl chloride obtained by the chlorosulphonation of (2 - bromoethyl) benzene to a solution containing m-aminobenzaldehyde ethylene glycol acetate, acetone, water and potassium carbonate, (15) methacrylamidoacetaldehyde ethylene glycol acetal by treating at a pH of 7-9 and 0-5 DEG  C. an aqueous solution of aminoacetaldehyde ethylene glycol acetate with a dioxane solution of methacrylyl chloride, (16) p-methacrylyloxybenzaldehyde by treating a solution of p-hydroxybenzaldehyde and anhydrous triethylamine in methylene chloride at 15-20 DEG  C. with a solution of methacrylyl chloride in methylene chloride and (18) o-methacrylyloxybenzaldehyde by replacing the p - hydroxybenzaldehyde by salicylaldehyde. Specifications 600,023, [Group IV (a)], and 638,895 are referred to.ALSO:A polyvinyl acetal of a linear polymeric alcohol has a large number of intra-linear -CH2CHOH groups, the acetal also containing a plurality of extra-linear vinylidene, <FORM:0786119/IV (a)/1> , groups in a conjugated double bond system.  It is preferred that the acetal has a molecular weight of at least 5000, that the ratio of acetal to vinylidene group be within the range of about 10 : 1 to 1 : 10, and that 10-90 per cent of the hydroxy groups are acetalized with a terminally unsaturated aldehyde.  Specified aldehydes are acrylamidoacetaldehyde, beta-(methacrylamido) - propionaldehyde, alpha-vinylcrotonaldehyde, alpha - phenyl acrolein, ortho - acryloxybenzaldehyde, m - (alpha - ethylacrylamido) - benzaldehyde, 1 - vinyl - 4 - naphthaldehyde, 2 - acrylamido - 4 - naphthaldehyde, 4 - vinyl - 41 - formylbiphenyl and para-(2 - methacryloxyethoxy) benzaldehyde.  The vinylidine group may be preferably a carboxylic acid ester group, e.g. the ester groups derived from acrylic, methacrylic, alpha-ethylacrylic, beta - vinylacrylic, alpha - chloracrylic, alpha-phenylacrylic and para-vinylbenzoic acids, but may also be a sulphonic acid ester group or an ether group. In the most preferred type of polymer the vinylidene group comprises an ester radical corresponding to the alpha-methylene carboxylic acids having from three to five carbon atoms and the acetal groups are supplied by any aldehyde saturated or unsaturated, while in the latter case conjugated vinylidene groups may be present in both the acetal and the auxiliary e.g. ester groups.  Most preferably the aldehyde furnishing the acetal groups is an aromatic aldehyde of from seven to eleven carbon atoms in which the aldehyde group is directly attached to annular carbon of an aromatic carbocyclic ring.  The preparation of meta-methacrylamidobenzaldehyde-, para-vinylbenzaldehyde -, meta - (para - vinylbenzene sulphonamido) - benzaldehyde -, meta - methacrylamidobenzaldehyde/ortho - chlorobenzaldehyde -, meta - methacrylamidobenzaldehyde/3,4-dichlorobenzaldehyde -, methacrylamidoacetaldehyde -, and ortho - or para - methacrylyloxybenzaldehyde - polyvinyl acetals as well as of meta-methacrylamido benzaldehyde polyvinyl acetal containing acrylyloxy groups, benzaldehyde polyvinyl acetal containing acrylyloxy groups and n-butyraldehyde polyvinyl acetal containing methacrylyloxy groups is described.  The acetals admixed with an addition polymerization initiator, e.g. diacetyl, benzil, benzoin, pivaloin, benzoin methyl or ethyl ethers, a -methyl- or a -allyl- or a -phenyl-benzoin and preferably with a small amount of an inhibitor, e.g. hydroquinone or 4-hydroxydiphenyl give photopolymerizable compositions.  These compositions may also contain monomeric and polymeric poly-unsaturated materials, e.g. methacrylic and acrylic acid diesters of ethylene glycol, diethylene glycol and polyethylene glycols, and polymethylene glycols, divinyl benzene, crotyl methacrylate, diallyl phthalate, diallyl maleate and triallyl cyanurate as well as transparent fillers or reinforcing agents, e.g. the organophilic silicas, bentonites, silica and powdered glass. Specifications 600,023 and 638,895 are referred to.