DE627729C - Process for draw-spinning acetyl cellulose - Google Patents

Description

When wet spinning Acetyloellulose goes one usually made from acetone-soluble that after the Etylation process precipitated and then dissolved in a suitable solvent. The use of the adetyiation room for direct spinning in Influences generally led to no usable result because of the nature of the 'obtained silk, in particular

ίο regarding. Gloss and softness, unsatisfactory was.

It has been found that AoetyKerunga solutions prepared using acetic acid the cellulose in aqueous baths with considerable stretching and without danger the whitening of the threads can be affected if the hydrated acetylation mixture with the addition of aliphatic C-hydrocarbons, which alone Do not dissolve hydrated adetyl cellulose and are insoluble in the precipitation bath, like ζ. Β. Ethylene or Methylene chloride, is processed.

These additives can be added either before or after acetylation or hydration will. Depending on the type of acetyl cellulose and the spinning conditions, the FiäUbad can consist of pure water or Contain salts and the like. Since the thread is initially in. plastic. State fails, it succeeds this jerheblicb. to stretch ;: one receives E.g. at a withdrawal speed of over 100 m per minute with nozzles of 0.1 mm Wide, shiny threads with a single titer of o, 3 den., And tear strength of at least "200 g per 100 den.

When exercising the inventive Procedure has been found to be expedient, the thread first. through a warmer and then let it pass through a colder precipitation bath. Of course, the acetylating liquid can for spinning also contain additives such as plasticizers, resins, etc.

One already has AoetylceHulose solutions, which contain ajiphiatische hydrocarbons or aoetylenetetrachloride, in water or sp'n aqueous solutions, but the main component of these solutions is not acetic acid, as with the invention, but pyridime. The recovery of solvents from 50 ' the precipitation bath causes considerable difficulties in the known method, because in the Distillation both components and water pass over; tetrachloroethane also reacts with pyridine to form hydrochloric acid pyridine and trichlorethylene. Furthermore, one has

* / The patent seeker stated that the inventors were: Dr. AIfons Ascher I and Dr. Wolfgang Grub in Burgshausen.

sehon voEgesclilagenj tetrachlorethylene GeAi- • Lösetriacet ^ lQsüngefi "as a 'stabilizing agent to add; 'yon' a ptastification adien Wai ' kung was not known to jeUodV. Furthermore, methylene oxide and Ethylendidhlorid together with alcohol u ·. Like. As a solvent for solid adetyl - .. aeHulose used, while in the: Invention the aliphatic chlorinated hydrocarbons mentioned the hydrated acetylene. added to the cellulose.

In the method according to the invention, the one component, namely the chlorinated. Kohileiiwaislsler-StOfF, t. B, methylene chloride or ethylene chloride, distilled off and. to be reclaimed; In addition, the components do not go chemically four-bonded when heated

aö together .ein.

- "■ - · .- Example · 1 -—-": -.'-.; .-:

10 parts of linters are in the presence of 0.5 to ι part of H ₂ SO ₄ with 25 parts of acetic anhydride and 5 parts of glacial acetic acid aöetyÜert in a known manner and then hydrated until the Aöetonlöislidhkeit admit it. Diego's now ready-to-spin mass is in a known manner through nozzles in; Water.-vierspönnenj; whereby to achieve particularly) fine and soft threads. first water from 30 °, "afterwards !, solclies. from" 19: b ^ s_ 20 ° wefwendet, - ■ --- -I - "- . '/ - ■ -'- ■ _-: -". :. ''-,

ιό Teilfii; Linters: be, p

indicated ,, aoetylated; thereupon ... after

4Q would give from 6 TeÜen - Ethylendhlorid ^ m over As is known, 'hydrated' and correspondingly.

Proceed to example ι. The water temperatures during spinning are to be kept at 40 to ¹ 50 ⁰ or 10 to 20 °.

". . ,

Example 3

10 parts of linters are in a mixture "of ι part! acetic acid, 0.5 to 1 part sulfuric acid, 15 parts of ÄthylencMorid and 25 parts of acetic anhydride acetylated. the After the excess anhydride has been destroyed, hydration takes place in a known manner. The spinning takes place in the manner indicated in Example 2.

■ "■" ■ "" τ. · · Ι

Example 4

10 parts of linters are made in a known manner acetylated with retention of structure. After throwing off the excess acetic anhydride lind the diluent is the = triacetate in the presence of 10 parts Methylene chloride, 1 part acetic acid and 1 part Schwefelsätir.e "dissolved and, as in." "Example 1 indicated, hydrated.

Claims (1)

'' PATENT CLAIMS: _ .1. Process to draw spinning produced using acetic acid Adetylation solutions of cellulose in aqueous precipitation baths, thereby marked ' pert ,, that / öas hydrated 'acetylation : gemis'dh: with the addition of aliphatic CUorkoMenehydrogen, which only hydra- -. tized & Apetylcellulosie _: do not dissolve and - 1 are insoluble in the .FjäHbad, such as. B. Me-: ethylene pder _; , iMfliylencMQrid, processed - ■■ _ 2 .. method according to claim i, thereby marked that first ^ a 'warm and then 'used a colder precipitation bath will. ·