| 摘要 |
A cellulosic product is made by reacting ethyl, propyl, or butyl acrylate, in the presence of 0,01%-1% by weight of a divinyl or divinylidene monomeric compound having at least two ethylenic linkages which are in conjugation with other unsaturated linkages, which latter are themselves non ethylenic, with a paper substrate composed wholly or predominantly of cellulosic fibres, and polymerizing said acrylate and said monomeric compound in an aqueous medium at a pH not greater than 3,5 in the presence of a ceric compound which is soluble in at p least one component of the reaction medium until the weight of the acrylate combined with the substrate is between 100% and 900%, based on the weight of the substrate. A preferred monomeric compound is ethylene dimethacrylate, but in general monomers resulting from the full esterification of a glycol (especially ethylene glycol, propanediol-1,3, and butanediol-1,4) with an a , b ethylenically unsaturated carboxylic acid (especially acrylic or methacrylic acid) may be used. Specified compounds include ethylene diacrylate, propylene diacrylate, butylene diacrylate, propylene dimethacrylate and butylene dimethacrylate. Divinyl benzene and divinyl naphthalene may also be used. As ceric compounds may be used ceric salts, e.g. ceric nitrate, ceric sulphate, ceric ammonium nitrate, ceric ammonium sulphate, ceric ammonium pyrophosphate and ceric iodate, and ceric compounds capable of forming ceric salts under the acid conditions of the polymerization reaction, e.g. ceric oxide and hydroxide. Desirably, the weight of acrylate combined with the substrate is from 200-500%, and the process may be carried out at from -5 DEG C. to 100 DEG C., preferably from 10-60 DEG C. Superatmospheric pressure or partial vacuum may be used if desired. U.S.A. Specification 2,475,846 is referred to.
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