DE2257707A1 - DRY NOZZLE WET SPINNING PROCESS OF OXADIAZOLE POLYMERIZES FROM SULFUR ACID SOLUTIONS - Google Patents

Description

DR. BERG DJPL.-ING. STAPF

PATENTANWÄLTE 8 MUNICH 8O. MAUERK1RCHERSTR.

Df. Berg Dipl.-Ing. Stapf, 8 MOnchen 80, MouerkirchBretro6e 45

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Your writing

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Acts of law 22 Be / Scb

date

2 1 *. Nov 1972

Monsanto Company St. Eouis, Missouri / USA

"Dry nozzle wet spinning process from oxadiazole polymers Sulfuric acid solutions "

There are already several methods of making poly (aromatic oxadiazole) fibers known. So is in U.S. Patent 3,238,183 describes a process in which poly (aromatic hydrazide) fibers are subjected to heat to prevent the intra-linear itehydration

C-14-54-0113

—2—

303 ^ 22/109 "

• "nil" 8272 (98.8272) 4870 "(987043) 483 ₃₁ 0 (983310) Te.e ₈ ra _m m., BERGSTAPFPATENT Munich TELEX 05 24 SiO BERG d Bank, Bayeriichs Vereintbank Munich 453 TOO Poihehedc" Munich 653 43

To effect cyclization of the hydrazide bonds with formation of the corresponding poly (aromatic oxadiazoles). This procedure is quite complicated and therefore not technically attractive. The manufacture of the fibers by Wet spinning of sulphuric acid solutions of poly (aromatic Oxadiazoles) in a coagulation bath containing sulfuric acid is described by Y. Imai, J. Appl. Pole. May be. 14, 225-239 (1970) and Japanese Patent 37791/70. The wet spinning processes have several inherent ones Disadvantages, for example, can be the spinneret not heated or cooled independently of the coagulation bath which limits the ability to control processes that use this technique. If the coagulation bath is strong acids, for example sulfuric acid corrosion of the spinneret is an additional problem.

The present invention is therefore primarily concerned with a technically attractive process for the production of fibers from poly (aromatic oxadiazoles), in which the Disadvantages are overcome which the methods using the wet spinning techniques inevitably have.

The invention relates to the production of fibers with a high molecular weight from poly (aromatic oxadiazole) -hoiao- or -mischpolyraerisaten by a dry nozzle wet spinning process, including a solution of the polymer in a strong acid, 3Ο9 · 22 / 1Ο97 -5-

for example sulfuric acid and / or polyphosphoric acid, directed downwards through at least one nozzle into an inert one Gas medium, for example a medium that is essentially with the polymer is not reactive, such as air or oxygen, then in a coagulation bath, the one aqueous solution of a strong acid with a water content of at least 3Θ wt. # ·, for example 30 to 90 $, extruded and then the fiber is further processed by conventional solution spinning processes, for example by peeling the fiber formed, washing the fiber, drying the fiber and optionally by further drawing ■ the fiber in a heated environment. The gap or the distance between the nozzle or nozzles (multi-hole nozzles) and the coagulation bath can be 0.3 to 5 cm or more be.

The polymer solutions that are used to carry out the inventive Procedure are used - included in the we- * essential

(I) 1 to 15 wt. ^, Preferably 3 to 8 $, polymer, namely off

(A) Polymers with recurring structural units (basic molecules) of the formula

Il »

G-

30982271097

and or

- 4 - ■ "

(B) Polymers with recurring structural units the formula

(a) N N

Ii i

-Ar-C C-

χ /

and repeating structural units of the formula

(b) OHO

11 i

-Ar '- C-N-NH-O-,

where the molar ratio of the units (β) ί (b) 20:80 to 95: 5 and preferably 50:50 to 90i10 is and

(II) 99 to 85% by weight of a strong acid as a solvent for the polymer,

where in the formulas Ar and Ar ¹ in each case, independently of one another, a divalent aromatic radical and H is a C-- to C ^ -alkyl radical and preferably methyl or ethyl. The strong acid used as the polymer solvent is preferably sulfuric acid, for example fumed sulfuric acid with a content of up to 4-0, for example 2 to 40% by weight of sulfur trioxide.

The polymer and the polymer solutions that are used for the through Implementation of the invention can be used in. a one-step process, including an aromatic Dxcarbonsaurekoraponente or a mixture that

■ ■■ _fj_ 309822/1097

consists of the component and alkyl ester thereof, with Hydrazine or its inorganic salts in fuming sulfuric acid containing, for example, 30 # SO, preferably using a slight excess of hydrazine, such as a 0.5 to ^ 2.5 molar excess, implements. The polymer solution obtained is then adjusted to the desired polymer concentration, i.e. 1 to 15% by weight diluted by adding sulfuric acid.

The polyaromatic oxadiazoles) that make up the here described Fibers made have inherent viscosities (TJ, inh.) Of at least 0.2 "and preferably

at least 1.0 when at 25 ° ö at one concentration (0) of 0.5 g of polymer per 100 ml of solvent can be measured, this concentration being determined by dilution the spinning solution obtained with concentrated sulfuric acid. T inh. is given by the equation

> n - In (71'rel)

determines where Ή, is the relative viscosity, like them is determined with a capillary viscometer.

According to the preferred embodiments of the invention, the polymer is prepared in such a way that the reactants (I) hydrazine sulfate and (II) terephthalic acid or a mixture of ¹ terephthalic acid and isophthalic acid in a molar ratio of about 95/5 to 5Qi 50 or

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a mixture of (I) hydrazine sulfate and (II) a phthalic acid component and a methyl phthalate component in a molar ratio of about 95 'x 5 to 20:80 used, wherein the phthalic acid component of terephthalic acid or a mixture of terephthalic and isophthalic acids and the methyl phthalate component of mono- or Dimethyl iso- or terephthalate or mixtures thereof. When carrying out the preferred embodiments of the invention, the poly (aromatic oxadiazoles) contain para- or meta-phenylene radicals or a combination thereof.

The following examples serve to further illustrate the invention. In the examples, the fiber properties were measured on an Instron device and reported as T / E / M, where T is strength (Heiselange) up to breakage and M the module at 1 # elongation, both reported in grams per denier (gpd) and E is elongation to break expressed as the # phrase (#). the inherent viscosities as indicated in the examples were determined as indicated above.

example 1

A polymer solution of poly (p-phenylenoxadiazöl) was prepared by one 80.8 g of terephthalic acid and 64.4 g of hydrazine sulfate in 1230 g of fuming sulfuric acid (30 $ · SO *) polymerized at 120 ⁰ C, to a polymer having a woduroJa inherent viscosity of .3 * 7. he-

• _7 ~ 309822/1097

keeps awake. Dilute with 200 g of concentrated "sulfuric acid, the viscous solution by a 0.165 'mm 5-Lochspinndüse into a coagulation bath containing 52 $ strength by weight sulfuric acid at 250 ⁰ O. extruded. The spinneret was heated to. 195 G ⁰ and 1.27 cm gehal- above the coagulation bath. th. one then performs the fiber over a guide roll into the bath through a water washing roller, a neutralizing roller which rotates in an aqueous 4 $ strength by weight ammonium carbonate solution to, through a water bath at 95 ⁰ O via a further washing roller , a steam-heated Trocklnwalze and finally over a hot shoe at 383 ⁰ G. After application of finish, the fiber is wound up at a speed of 48.76 m / min. During spinning, the fiber was 6.5 fold-around The fiber had the following strength properties (breakage of the thread bundle, Instron):

Tear length: 5.2 g / den.
Elongation: $ 5.1
Module: 189 g / den.

and it had the following strength values prior to hot stretching: 3.1 g / den. / 35 ^ / 93 g / den.

Example 2 ■

A polymer solution of a poly (p-phenyleneoxadiazole) / (m-phenyleneoxadiazole) - (90/10) mill polymer was prepared by adding 72.7 g of terephthalic acid, 8.1 g of isophthalic acid and 64.4 g of hydrazine sulfate in 1230 g of fuming sulfuric acid {30 ° / o SO,) polymerized. laugh thinning 309822/1097. _Q

with 50 g of concentrated sulfuric acid, the polymer-Oftinh = 3.3) lö8ung was prepared from a 0.152 mm-5 LochspinndüBe, which is maintained at 16O ⁰ G, cm above an air gap of 1.27 in a coagulation bath extruded containing 50, 5 $ sulfuric acid

contained at 23 ⁰ G. Using a spinning process similar to that in Example 1, in which a 4% sodium carbonate solution was used as the neutralizing bath, the fiber was wound up at a speed of 30.4 m / min. The fiber had the following strength properties

Tear length ι 4.4 g / den. Stretching »3ι4 $
Moduli 173 g / den.

Example 3

Similar to Example 2, a poly (p- / yn-phenyleneoxadiazole) - (85/15) misohpolymer solution was made from 68.7 g of terephthalic acid, 12.1 g of isophthalic acid and 64.4 g of hydrazine sulfate in 1230 g of fuming sulfuric acid (30 $ SO ₅ ) at 120 ^° C. The spinning solution (-Jh _n J ₁ = 3.3) was spun from a 0.190 mm 3-hole spinning nozzle, which was kept at 130 0, through an air gap of 1.27 cm into a coagulation bath, the 50.5 $ sulfuric acid at 23 ° G contained. Using the procedure of Example 1, a fiber was obtained at 64.6 m / min, with the following strength properties:

Tear length 1 4.6 g / den.

Elongation t 3.5%

Moduli 182 g / den.

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Example 4

A spinning solution of poly (p-phenyleneoxadiazOl / U-methylterephthalhydrazide) copolymer was prepared by adding 58.2 g of terephthalic acid, 7.6 g of dimethyl terephthalate and 51.3 g of hydrazine sulfate in 984 g of fuming sulfuric acid (30 $ SO ₃ ) Toei 12O ⁰ O polymerized. After dilution with 200 g of fuming sulfuric acid and 100 g of concentrated sulfuric acid, the spinning solution (?} Inh = 3.8) passed through. a 0,165 mm-5 Lochspinndüse which was maintained at 125 ⁰ C, and an air gap of 1.27 cm extruded in.ein coagulation bath containing 8 $ sulfuric acid at 23 ° 0th Using a spinning process similar to that in Example 2, the fiber was wound up at a speed of 38.06 m / min. The fiber had the following properties:

Tear length: 5.7 g / den.

Elongation: $ 3.7

Moduli 202 g / den.

Example 5

A poly (p-phenyleneoxadiazoi / N-methylterephthalhydrazide) -isohpolymer spinning solution ("7 [ inh = 3.3) was prepared as in Example 4, except that an 85/15 molar ratio of terephthalic acid to dimethyl terephthalate was used spinning solution was spun as in example 4 at a spinneret temperature of 90 ⁰ G and 13 $ 0 as the acid at 25 ° coagulating. the fiber was wound up at a speed of 148.3 m / min, HAT 309822/1097 " ¹⁰ ~

- ίο -

te the following characteristics;

Tear length: 7.8 g / den. Strain! $ 3.7 Module: 231 g / den.

Example 6

Another oxadiazole / N Methylhydrazidmischpolymerisat - (* \ inh = 3.9?) -Spinnlösung was prepared as in Example 4 with a 80/20 molar ratio of terephthalic acid to dimethyl terephthalate and by a 0.165 mm 5 ~ Lochspinndüse at 6O ⁰ C and an air gap of 1.27 cm in a water bath at 25 ° C as a coagulating medium. After a similar spinning process as in Example 2, the fiber, which was wound at a speed of 75.2 m / min, had the following properties;

Tear length: 7.3 g / den. Elongation: 4.2 $ modulus 231 g / den.

Example 7

An oxadiazole / N-methylhydrazide copolymer ("^ inh - 3» 5) -3 spinning solution was prepared in a manner similar to that in Example 4, but with a 75/25 molar ratio of terephthalic acid to dimethyl terephthalate Air gap of 1.27 µm and then extruded into 14 # strength sulfuric acid at 25 ⁰ O. Using a spinning process similar to that in Example 2, the paser was produced at a rate of

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from 132.2 m / min, wound up. The fiber had the following Characteristics:

Tear length: 9.5 g / den «

Elongation: $ 4.0

Module: 301 g / den. .

Example 8 . .

An oxadiazole / K-methylhydrazide copolymer (^ inh = 2.9) spinning solution was prepared as in Example 4 but with a 70/30 molar ratio of terephthalic acid to dimethyl terephthalate. The spinning solution became one. Fiber at a speed of 128 m / min, spun, including reacting a 0.165 mm-5 lochspinndüse at 80-100 ⁰ G, a 1.27 cm air gap and a water-containing KoagulierungslDad used, "The fiber had the following properties;

Tear length: 8.5 g / den. Elongation: $ 4.1
Module: 262 g / den._

Example 9 . ^:

An oxadiazole / N-methylhydrazide copolymer (T ^ inh = 2,6) dope was as in Example 4, but using a 65/35 molar ratio of terephthalic acid to dimethyl terephthalate. The spinning solution was in Fibers at a speed of 62.2 m / min, spun, including a 0.165 mm 5-hole spinning nozzle "at 80 0, an air gap of 1, "27 cm and water" at 25 ° 0 as a coagulation medium ends. The fiber had the following properties:

309622-1097

Tear length: 5.8 g / den. Elongation: $ 3.4
Module: 220 g / den.

Example 10

An oxadiazole / N-methylhydrazide copolymer 2,9) spinning solution was prepared in a manner similar to that in Example 4, but using an 80/10/10 molar ratio of terephthalic acid, isophthalic acid and dimethyl terephthalate. The spinning solution was used for fiber at a speed of 124.9 m / min, under a .Use at 90 ⁰ O, a Luftiwleohenraums of 1.27 cm and i3 $ sulfuric acid at 25 ⁰ O 0.23 mm 5-Lochspinndüee ale coagulation spun. The fiber had the following properties1

Tear length: 5.1 g / den. Elongation i $ 3.0
Module: 188 g / den.

Example 11

A mixed polymer ("? ^ Inh = 3» 6) spinning solution of the same composition as in Example 7 was in a fiber at a speed of 97.5 m / min, using a 0.23 mm 50-hole spinning nozzle "at 75 ⁰ C, an air gap of 0.63 cm and 25% sulfuric acid at 25 ° C as a coagulation agent
following properties:

25 ⁰ C used as a coagulation medium. The fiber had that

. - ^:; .- '\ -13-309822 / 1097

Tear length: 8.5 g / den
, Elongation: 5.1 fo
Module: '244 g / den "'

Example 12 . ■ · ■ ■

A (p-phenyleno ⁴ xadiazole / N-methylterephthalic hydrazide) copolymer ( ty \ lrui = 2.8) was prepared using a 45/55 molar ratio of terephthalic acid to dimethyl terephthalate. The spinning solution was added to a fiber at a speed of 239.8 m / min using a _o 0.23 inm / iO-L spinneret och at 12O ⁰ C, spun an air gap of 1.27 cm and water as Spinnbadkoagulierungsmittel. The fiber was neutralized with a 4% sodium carbonate solution before drying and hot drawn at 409 ° C. The fiber had the following properties:.

Tear length: 9.0 g / den

Elongation: 4.3 ^

Module: 25B g / den

Denier / thread: 1.5

Example 13

A (p-phenyleneoxadiazole / IT-methyl terephthalhydrazide) copolymer (3 inh = 3.0) was prepared from a 25/75 molar ratio of terephthalic acid to dimethyl terephthalate, and a 1.5 molar excess of hydrazine sulfate. The spinning solution was in a fiber at a speed of 145.8 m / min, using a 0.23 mm / 10 at 90 ⁰ C Lochspinndüse, an air gap of 1.27 cm

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and water spun at 25 ° C as a coagulant «» Die Fiber had the following properties

Tear length j 7.4 g / den.

Elongation: $ 4.9

Modulus 198 g / den.

Denier / thread: 1.3

Example 14

A (p-phenyleneoxadiazole / N-methylterephthalhydrazide) -MiBola polymer (^ inh = 3.6) as described in Example 7, was in a fiber at a speed of 196.9ia / min. using a 0.23 mm / 10-hole spinning nozzle at 167 ⁰ O, an air gap of 1.27 cm and an acidic, aqueous 40% solution of ammonium sulfate as a coagulant. The fiber was neutralized with sodium carbonate before drying and knitted hot. The fiber had the following properties «

Tear length 9.4 g / den elongation: 5.2 $
Module »282 g / den.

According to a specific embodiment of the invention, the polymer solution, which is extruded through the outlet openings of the spinneret into the coagulation bath, is obtained at a temperature while the coagulation bath is kept at a higher or lower temperature. The temperature of the polymer solution is preferably kept at a temperature above about 7O ⁰ O, for example in the range from 70 ° to 309822/1097 -15-

O 225 and the coagulation bath at room temperature, that is about the temperature of the Poylmerisatlösung 'may for example duroh heating the spinneret and / or the solution reaches 25 ⁰ C.. The effect of extruding the heated polymer is that the flow rate of the polymer solutions (spinning solutions) through the spinning outlet openings is increased, and that smoother surfaces and, as a result, higher spinning speeds are achieved Oxadiazole copolymers keep the Koagulatiqnsbad at relatively cool temperatures, ie less than 50 ⁰ C, in order to obtain optimal fiber properties.

According to a further specific embodiment of the invention, the acid contained in the fiber is neutralized before the fiber is dried. If the acid is not neutralized, a degradation of the properties of the fiber after drying the fiber, Z ₀ can occur as during storage. It can be assumed that such degradation is caused by a chemical reaction of the acid with the fiber preparation. The acid contained in the fiber can be neutralized by treating the fiber with: An inorganic basic compound, such as aqueous solutions of ammonia (Ia) ₂ -CO ₃ , (UH ^) ₂ CO ₃ , FaHCO ₃ , NH ₄ HCO ₃ , a metal hydroxide, for example KOH and the like? an organic salt such as sodium acetate, etc; an organic base such as triethanolamine, triethylamine, pyridine, etc. brings into contact. 309822/1097 -16-

Appropriately, the. Compound that is used to neutralize the acid present in the fiber is used in the washing bath that is located downstream or after the coagulation bath.

Furthermore, instead of an aqueous one, the coagulation bath; acidic solution, an aqueous salt solution! which is an aqueous solution of an acid salt, such as ammonium sulfate, sodium sulfate

■■ '■ ι

fat, contain magnesium chloride. In this regard it is

Example 14 watch.

Instead of using aromatic reactants, as in the examples, for the preparation of the polymers described here, other aromatic reactants can also be used, such as a compound of the formula

where R · is a single bond, -CHp- or -0- and X is -000H, the amide or nitrile derivative thereof or a salt thereof, and -COOR, where R is a CL - C. Is ethyl, or a compound of the formula

wherein X has the same meaning as above.

Claims: 309822/1097 -17-

Claims (14)

j τ ,? - Godfather nt.a.n sprue he: 1. Process for the production of fibers from poly (aromatic >, ■ see Oxadiazole) -polynierisaten with repeating structural units (I) of the formula N- - Ν I I 0 0- or (II.) of the formulas (a) 1 I. -Ar-C. O and (b) QRO Il I I -Ar'-C-N-NH-C- wherein each Ar and Ar 'are independently of one another divalent aromatic hydrocarbon and R is a C ^ -bis C ^ -alkyl radical and the molar ratio of the units (a) :( b) is between about 20i80 and about 95: 5, thereby marked that maj] a solution that zwisehen about 1 and about 15% by weight of polymer and sulfuric acid or contains polyphosphoric acid or mixtures thereof, directed downwards through at least one spinneret in a gaseous medium and then in a coagulation bath, that is an aqueous solution of the specified acid or a 30 ^ 822 / 109-7 _ ₁₈ _ - Ιο - aqueous solution of a salt wherein the water content is at least 30 wt.%, extruded, wherein the distance between the nozzle and the bath is at least 0.3 cm, subtracting the Paser formed from the bath, washed and then dried. 2. The method according to claim 1, characterized in that as a coagulation bath in essentially an aqueous solution of sulfuric acid is used. 3. The method according to claim 1 d a d u r c h g e indicates that an aqueous salt solution is used as the coagulation bath, 4. The method according to claim 3, characterized that ammonium sulfate is used as the salt. 5. The method according to claim 1 dadurch'.gekisiert that air is used as the gaseous medium. 6. The method according to claim 1, characterized that the poly (aromatic oxadiazole) used is poly (p-phenyleneoxadiazole). -19- 309822/1097 7 · Method according to claim 1 characterized that as polyaromatic oxadiazole) PolyCp-phenyleneoxadiazole / m-phenyleneoxadiazole) used, the molar ratio of the p-phenyleneoxadiazole units to the m-phenyleneoxadiazole units 90:10 bis 50ι50 is. 8. The method according to claim 1, characterized in that one so adjusts the solution is that it containing between 3 and 8 wt.% Polymer. 9. The method according to claim 1, characterized in that that as polyaromatic oxadiazole) PolyCp-phenyleneoxadiazole / N-methylterephthalhydrazide) used, where the molar ratio of the p-phenyleneoxadiazole units to the N-methyl terephthalhydrazide units 95: 5 to 20:80. 10. The method according to claim 1, characterized in that the poly (aromatic oxadiazole) used is PolyCp.-phenyleneoxadiazole / m-phenyleneoxadiazole / H-methylterephthal / isophthalhydrazide), the molar ratio of the p-phenyleneoxadiazole units to the m-phenyleneoxadiazole units being 95 ^ 5 to 50:50 and the molar ratio of the phenyleneoxadiazole units to the N-methylterephthal / isophthalhydrazide units is 95 ^ 5 to 20:80. - - ' _P0- .309822 / 1097. · 11. The method according to claim 1, characterized that after the fiber is dried, the fiber is further drawn in a heated environment. 12. The method according to claim 1, characterized g β-denotes that the polymer! sat solution at one temperature and the aqueous acid solution at a second temperature. $ 1. Process according to claim 10, characterized in that the polymer solution is kept at a temperature of at least 70 G and the aqueous acid solution is kept at a temperature below 50 ⁰ O. 14. The method according to claim 10, characterized in that the Polymerisatlöfeung at a temperature between 70 and 225 ° C and the aqueous acid solution between room temperature and 50 ⁰ C » 309822/1097