Topochemical modification of cellulose textile materials

摘要

Natural or regenerated cellulose textile materials, e.g fibres, yarns or fabrics, are given a wide range of permanent finishes by reacting part of the hydroxy groups of the cellulose with an olefinic esterifying or etherifying agent so as to form an alkylene ester or ether of cellulose without loss of fibrous structure, and then copolymerizing the so-formed cellulose derivative with an olefinic monomer to form a chemically combined resinous composite with the fibres. Specified esterifying agents are acrylic, methacrylic, crotonic, isocrotonic, itaconic and maleic acids, anhydrides or acyl halides, and specified etherifying agents are allyl, methallyl and crotyl alcohols, alcoholates or halides. The olefinic monomer is one containing a vinyl, allyl, propenyl, vinylene or vinylidene group such as acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, styrene, divinyl benzene, acrylonitrile, vinylidene chloride, vinyl acetate and allylidene diacetate. Slightly modified fibres, e.g. viscose rayon pretreated with glyoxal or formaldehyde and cotton slightly esterified with acetic acid or etherified to the carboxymethyl ether, may be treated, as well as blends of cotton or viscose rayon with nylon or other non-cellulosic fibres which are not soluble in or sensitive to the reaction media. In examples, esterification is effected by first soaking a viscose or rayon fabric in aqueous formic acid and then immersing it for a few minutes at various temperatures maintained below 45 DEG C. in an aqueous solution of the esterifying medium containing perchloric acid as catalyst, or in one case by passing the fabric through the esterifying medium and then drying at 50 DEG C. for 5 minutes. In another example, etherification is effected by soaking cotton yarn in aqueous caustic soda and then heating and agitating with a solution of methallyl bromide in carbon tetrachloride for 16 hours. Copolymerization with aqueous emulsions of various olefinic monomers containing emulsifiers and catalysts is then effected at temperatures of 65 DEG or 70 DEG C. for periods varying between 20 minutes and 2 1/2 hours.ALSO:Natural or regenerated cellulose textile materials, e.g fibres, yarns or fabrics, are given a wide range of permanent finishes by reacting part of the hydroxy groups of the cellulose with an olefinic esterifying or etherifying agent so as to form an alkylene ester or ether of cellulose without loss of fibrous structure, and then copolymerizing the so-formed cellulose derivative with an olefinic monomer to form a chemically-combined resinous composite with the fibres. Specified esterifying agents are acrylic, methacrylic, crotonic, isocrotonic, itaconic and maleic acids, anhydrides or acyl halides, and specified etherifying agents are allyl, methallyl and crotyl alcohols, alcoholates or halides. The olefinic monomer is one containing a vinyl, allyl, propenyl, vinylene or vinylidene group such as acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, styrene, divinyl benzene, acrylonitrile, vinylidene chloride, vinyl acetate and allylidene diacetate. Slightly modified fibres, e.g. viscose rayon pretreated with glyoxal or formaldehyde and cotton slightly esterified with acetic acid or etherified to the carboxymethyl ether, may be treated, as well as blends of cotton or viscose rayon with nylon or other non-cellulosic fibres which are not soluble in or sensitive to the reaction media. In examples, esterification is effected by first soaking the viscose or rayon fabric in aqueous formic acid and then immersing it for a few minutes at various temperatures maintained below 45 DEG C. in an aqueous solution of the esterifying medium containing perchloric acid as catalyst, or in one case by passing the fabric through the esterifying medium and then drying at 50 DEG C. for five minutes. In another example, etherification is effected by soaking cotton yarn in aqueous caustic soda and then heating and agitating with a solution of methallyl bromide in carbon tetrachloride for 16 hours. Copolymerization with aqueous emulsions of various olefinic monomers containing emulsifiers and catalysts is then effected at temperatures of 65 DEG or 70 DEG C. for periods varying between 20 minutes and 2 1/2 hours.