GB469007A - Manufacture of compositions containing cellulose derivatives and of shaped structures therefrom - Google Patents

Abstract

Artificial threads and fibres, bands, coatings, dressings, cements, plastic masses, and other shaped structures are made from the product resulting from the bringing-together of a cellulose ether in solution or suspension in caustic alkali, and a product of the reaction of carbon disulphide on alkali cellulose, such latter product not being in solution or in incomplete solution in water or alkali solution. By such method the cellulose xanthate is brought readily into solution, and there is produced even from undepolymerized cellulose, solutions containing a high total percentages of cellulose, say 9--12 or more per cent, which are flowable and easily filterable; the structures resulting from these solutions are of good strength and extensibility; in addition, solutions can be obtained with the use of relatively small proportions of carbon disulphide, for example, less than 30 per cent of the cellulose and cellulose ether, preferably less than 20 per cent, even less than 10 per cent, for example, 3--1 per cent. The cellulose ether may be soluble in caustic alkali at room temperature or may be brought into solution by cooling as by the process described in Specification 212,864; cellulose esters which are insoluble or only partly soluble under these latter conditions may also be employed. Solution of the cellulose xanthate in the solution or incomplete solution of the cellulose ether may be effected by cooling to 0 DEG C. or lower. The cellulose p ether may contain less than one, even less than 0,5 substituted or unsubstituted alcohol radicle per C6H10O5 unit, and such radicle may be alkyl, hydroxyalkyl or hydroxy acid, or a mixture of these. The proportion of cellulose ether to cellulose xanthate may vary within wide limits, for example, from 0,1 : 1 to 29 : 1. For the working-up of the cellulose ether-cellulose xanthate solution into shaped structures there may be employed baths capable of coagulating viscose, in particular there may be used baths having a plasticizing effect on the coagulated product, for example, baths containing 25--70 per cent sulphuric acid; or the originally coagulated product may be plasticized in a later bath. In the case of such products as artificial threads, the latter may while in the coagulation bath or during their travel to the collecting device, be subjected to stretching. There are a number of examples describing the production of suitable cellulose ethers and cellulose xanthates, and the production of the mixed solutions thereof, and the working-up of such solutions into artificial structures. Specifications 25246/11, [Class 2 (iii)]; 177,810, 200,816, 200,834, 203,346, 203,347, 212,864, 212,865, 231,807, 231,808, 231,809, 231,810, 231,811, 281,352, 312,197, 323,731, 323,732, 335,993, [all in Class 2 (ii)], 341,899, 356,776, 357,527, 357,595, 374,964, 390,517, 393,932, 408,932, 408,950, 427,622, 457,031, 459,122, 459,123, 462,456, 462,712, and 462,713, also are referred to.