DEP0047506DA - Process for the production of soluble cellulose derivatives - Google Patents

Description

Irofesjor Dy, Otto Payei and Dr-Erns' ^ Ojier (reide Ls ve '; ι,'

can 23

proceedings
for the production of * Gellulosederiyaten.-

It is known that from cellulose and Fonoi isocyanates, special aromatic isocyanates such as kheW ^ i ^ oG ^ nat ^ C urethane can throw * (Compare ⁴¹¹ SiH? 544 777)

The production of these cellulose derivatives is made more difficult by the fact that water must not be present during the hot reaction, since the isocyanates react with vaseers to form substituted ureas. Dry cellulose in the form of cotton "Bauin? IOll = Linters _s wood pulp, etc." is so unreactive that in inert, anhydrous organic solvents, such as pyri ^ in etc., a conversion into T does not look for derivatives at all or only incompletely long reaction times take place out of the sea »

It was therefore necessary to swell the cellulose or alkali cellulose in vaaaer, acids or salt solutions and ^{to displace the 1} vaSrer with inert water-miscible solvents, in particular fyridine, and to convert the cellulose, which is in a swollen, reactive form, with calcium cyanates " This failure is fundamentally and unsuitable for carrying out the reaction industrially. Even cellulose fibers that have been pretreated in this way only bead up slowly and imperfectly = converts into soluble derivatives

¹ Eb has now been found that the uniformity of dry native cellulose, such as cotton, linters, HolzzellsHoff and the like, Biit

^ onoisocyanates, especially aromatic isocyanates ^ per phenyl isocyanate, chloro-phenyl isocyanate, p-naphthyl isocyanate and the like "is completely and in a short time possible, if the organic bases used as the reaction medium" throw metal salts which, with the bases concerned, possibly at a higher temperature Form soluble addition compounds. This Addit'ons compounds, eg _o extending ava Ivridin and zinc chloride bilden- $ e crystallized adduct of 2 T / oil PyridJn and 1 Ivöl Zankehlorid "can also fjeson ^ eri; produced - and dissolved in the tertiary bases «.

Raise tertiary bases such as yridine can be di-substituted by mono ^ and polycyrboxylic acids ^,?. .B _e Dime thy lformam id _} Tetrainethvloxamid ^ retrame thy Iglu taramid has been used as a Realitionsmediuai * Here, too, the reaction is carried out by metal salts that form organic adducts with Ίϊβ-sen substances or the above-mentioned adducts from inorganic l / etallsa] zen rrit tertiary bases »strongly accelerated. Especially gUnctig is the fact that in the OF INVENTION ^ un ^ convention under solvents used un he ÄU3atz the ovemr-esrnnnten i ^J i @ t © llsalg @ nieht only AEIE monomeric laocyanete, but also their dimers such * B _e the custody of Phenylisocyannt Easily formed H.N'-diphenyl-K.B'carbonylurotoff (dimeric phenyl isocyanate) can be reacted with cellulose, whereby these substances react like free monoisocyanate.

Stirred Vird dry cellulose in the above berchriebenen reaction media at 110 ° effective, so swells eie strong and "ent in a short time in solution ₀ ^ US ^ the colorless or pale gelbverfäibten highly viscous Lb'eungen kann_das formed, OelluloDeurethan about by take there into dilute ii 'inera! acids are isolated. Be obtained from the Trodukt -. 'UICH üxtralftjon with io'cun ^ smitteln as benzene, toluene, alcohol, etc.-of Diphenylfceinstoff and ^{r is} the fibrous Celluloeeurethane as accelerators zugesetztenVerbinrlun n ^ N ^^ nt "The Brhaltenen contain pure white with the use of phenyl -Isocyanate $ 7.9 to $ 8.1> nitrogen. You are in einer'Vielzahl organic solvents, including acetone, Eseigsster, chloroform _s Kethylenchlorid etc ".klar soluble. The solutions are extremely viscous. The decomposition

C ¹ CS Celluloseoheny! Urethane is about 29 °, the melting point 320 ° with decomposition. The Celluloscurethane can su UAW films, fibers, Bkniern * processed or rit suitable plasticizers as a splash ^ used ussroeteriel uni "also particularly advantageous to L;> Finr ck purposes Verwendimg _s s where the high temperature resistance _β gros ^ s adhesion to documents! low »" aasoraufnahne ani favorable electrical properties also "at high temperatures for many purposes are particularly advantageous»

example 1

10 parts! .Inters 2. hours bei./lOO ⁰ protected dried in a ge ^ cn moisture apparatus untej effective leadership nit a solution of 40 parts of dry crystalline At · "laferun ^ sverbindung zinc chloride-pyridine and 30 parts> henylisocy -ftiat in 250 parts of lyridine ". The heat is broken down to 110 °. The cellosis fibers swell long, and in an hour a homogeneous, externally viscous solution the after precipitation in water and extraction with alcohol 31 j Ie .TE one Gell u los your th ^ ans be iepliert can ^ _s d s 8.1 # nitrogen containing schmilet at 320 °, and, among other pure in pyridine _s m- " Cresol "Acetone, iiesigester, Jv'ethylenchloriä, Chloroform" carbon tetrachloride Clearly soluble ict.

Example 2

10 parts of linters (dried at 100 ° for 2 hours) are heated to 110 ° in 200 ecm of pyridine containing 40 parts of pyridine-zinc chloride and 30 parts of 3 ^{%, K>} diphenyl-N _e K ^{f -carbonylurea, with stirring} . A clear, pale yellowish colored zyhviacose solution is obtained in 3 hours, from which the theoretical amount of a cellulose trirhenyl urethane can be isolated. The substance is the same as it is obtained according to Example 1 »

Example 3

Parts of linters are mixed with a solution consisting of 200 parts.

Claims (1)

leri dimethylformamide, 40 parts • yridin-ZinJcchlorid αηύ 3Ü> ~ parts Phenylisocvi.nat "behändelt _t as in Example 1 'described. Jn '5 3Pt ^ en - \ ± ί · ύ a homogeneous viscous solution e rna Itesn, sus <1er 51 »2 parts a * s 1". Look for Cellulosed ethane- medium viscosity
isolated ner s can * Process for * Manufacture: <ng of lüs borrowed cellulose derivatives through conversion of dry native r cellulose with isocyanates in
organic bases (ladurch gekennseichnet _s flass the solvent for cl'u I ^ ocy'anat verweniston bases metal "! ζβζzugesetzt VICR ^f 's ^ What π it $ .en bases loslache A""dit jonsvörbinlun ^ s zn
make up _r * de * dUfe4 ΛΖ'ά ^ ^ Afi ^ / Procedure pv & w ^ ss claim. 1, characterized in that the j as Pyrirün kinkciilorid uses τ / ird. h "^;.
Process ge ^ iss Ans ^ rtTShi ^ l 1 and 2 * by göliennzeichnat that -as isocyanate an "imeres Isocysn ^< 5t _; v? Ie S ₅ H '- * Diphenyl-IÜ.K
carbonylhorn.'toff ver <used ^ is ,,