Patent GB-318967-A (GB)
Abstract: 318,967. I. G. Farbenindustrie Akt.- Ges. Sept. 13, 1928, [Convention date]. Carbohydrate esters.-Derivatives of polymeric carbohydrates which contain one or more saturated or unsaturated fatty acid radicles and one or more saturated or unsaturated cyclic substituted fatty acid radicles are used for preparing elastic products by working them up by any process suitable for working rubber, guttapercha or balata, particularly by calendering and vulcanizing. As simple or unsaturated fatty acids there may be selected those with any desired length of simple or branched carbon chains, with any desired number and position of double linkings and with any desired number and kind of acyclic substituents, such as halogen, unsubstituted or substituted hydroxyl groups, ethylene oxide groups, thiocyanate, amino or organometallic groups. As saturated or unsaturated cyclic substituted fatty acids there may be used acids of the type of phenylacetic acid or napthenic acid and in particular all fatty acids of the stated kind so far as they contain as substituents saturated or unsaturated carbocyclic or heterocyclic rings with any desired number of atoms. The various acid radicles may be introduced into the carbohydrate. molecule by any known process suitable for esterifying polymeric carbohydrates, for instance as described in Specification 300,942, [Class 2 (ii),. Cellulose &c.]. By adding sulphur during the working up of these carbohydrate derivatives the known vulcanization effects are obtained. The products possess the properties of rubber, guttapercha and balata; they withstand the action of acids, alkalis and atmospheric oxygen; they can be moulded both in the form of solutions at low temperatures and without solvents at about 80-100‹ C. and have a considerable elastic extensibility which is markedly independent of the temperature. They may be used for all purposes for which rubber, guttapercha and balata have hitherto been used and are particularly suitable for making plates, films, threads, insulating. masses, impregnating masses, coatings and the like. The products may be worked up alone or mixed with colouring matters, other derivatives of polymeric carbohydrates, rubber, guttapercha, balata or depolymerization products and derivatives of these or their synthetic substitutes such as hydrogenized caoutchouc, halogenized caout-- chouc or butadien caoutchouc. They may be regenerated in the usual manner for rubber, guttapercha or balata. In examples cellulose naphthenate-oleate or cellulose phenylacetate-oleatelaurate is intimately mixed at 90-100‹ C. with sulphur in a kneading machine and then heated in a suitable mould under pressure at 140‹ C. to give for example a highly elastic plate. In another example, starch naphthenate-oleate-stearate, with or without added matter of the kind described, is rolled at 100‹ C. into thin skins or a solution of this ester in a suitable solvent, such as carbon tetrachloride, is poured in known manner to produce films. The films or skins are vulcanized cold either by immersing them in a solution of sulphur chloride in petroleum ether or by exposing them to the vapour of sulphur chloride and then washing them in an alkaline bath to give elastic films of 100-200 in. thickness. Specification 289,063, 305,947, and 327,165, [all in Class 2 (ii), Cellulose &c.are referred to..