| 摘要 |
Light-sensitive polymeric compounds are prepared by condensing a polymer or copolymer containing acyl groups with an aromatic aldehyde of formula QCHO, where Q is an aryl group of the benzene or naphthalene series (substituted or not). Specified polymers are a - naphthal -, isopropylbenzal -, p - hydroxybenzal-, p-dimethylaminoo-chlorobenzal-, p-acetamidobenzal-, p-sulphobenzal-, anisal-, and veratral-acetyl benzenes, polyvinylbenzal acetophenone, polyvinylanisal acetophenone and numerous others. The acylated polymer is preferably a polymer of an acylated vinyl benzene or naphthalene which is then condensed with preferably an excess of the aromatic aldehyde in from about 1/10 to about 25 to 50 mols. of aldehyde per mol. of monomers in the polymers to yield the polyvinyl arylidene acetophenone. Partially acetylated polystyrene, which may be used, is prepared by treating a carbon disulphide solution of polystyrene with acetyl chloride in the presence of ammonium chloride. Alternatively an acetylated styrene copolymer may be obtained by copolymerizing a mixture of a vinyl acetophenone (which may be prepared by depolymerizing polyvinylacetophenone) with a compound containing a -CH=C< group, followed by condensing acyl groups of the polymer with the aromatic aldehyde. This condensation is carried out in the presence of a dehydration catalyst, e.g. sulphuric acid, phosphoric acid, acetic anhydride, phosphorus pentoxide, toluene sulphonic acid, trimethyl benzyl or tetramethyl or tetraethyl, or tetraethanol ammonium hydroxides, trimethyl benzyl ammonium butoxide, sodium hydroxide, or sodium methoxide in the presence of a solvent, e.g. 1,4-dioxane, benzophenone or a large excess of the aldehyde. Specified -CH=C< containing group compounds are styrene, acrylonitrile, vinyl acetate, vinyl ketones, vinyl ethers, methyl methacrylate, isobutylene and maleic anhydride. Specifications 695,197, [Group XX], 713,947, 717,708, 717,710, 717,711, 717,712 and 732,602 and U.S.A. Specification 2,566,302 are referred to. |
