DE2651534A1 - FIBER-FORMING DISORDERED POLYAMIDS - Google Patents

Description

DR. BEUG DIPL.-ING. STAFF DIPL.-ING. SCiIWABE DR. DR. SANDMAIR “ _R

PATENT LAWYERS ^

8 MUNICH 86, POST BOX 86 02 45

Dr. Berg Dipl.-Ing. Stapfund Partner, 8 Munich 86, P.O. Box 860245 Your reference Our reference 8 MÜNCHEN 80 -1 "j Your ref. Our ref. Mauerkircherstraße 45

Lawyer File 27
Be / Sch

Monsanto Company St. Louis, Missouri / USA

"Fiber-forming disordered polyamides"

The invention relates to fiber-forming disordered, i.e. random arranged copolyamides formed by melt polymerization of the hexamethylene diamine salts of certain aromatic and aliphatic dibasic acids are made. Annealed fibers made from the copolyamides of the invention have exceptional properties such as dimensional stability and are suitable for industrial and textile purposes.

14-54-0221A GW

Telegrams: BERGSTAPFPATENT Munich Banks: Bayerische Vereinsbank Munich 453100 TELEX: 0524560 BERG d Hypo-Bank Munich 3892623 Post check Munich 65343-808

7 0 9 8 2 1/10 0 0

In this specification the term - "fiber" means continuous endless yarn, monofilament, tow and spinnable staple fibers,

- "6TA units" units of the formula

0 O

-NH - (- GH ₂ - ^ NH-C - \ v / h C- - "6IA units" units of the formula

O O

Il> v Il

OH ₂ -> gNH-C -S? ^ Jp C-

- "6RA units" units of the formula

0 0
ti η

-NH

wherein R is an O ₇ - to C _x . _{Q is} alkylene group,

- "66 units" 6RA units, where R is - (- CH ₂ - ^,

- "6TA / 6IA polymer" is a random copolymer containing recurring 6TA and 6IA units, 50 of which are to 80 mole # of the units are 6TA units and

- "6TA / 6IA / 6RA polymer" a random copolymer which consists essentially of 6TA ₇ 6IA and 6RA units.

In British Patent 1,382,551 the manufacture is of dimensionally stable staple fibers made of 6TA / 6IA polymers by means of described a batch process in which an aqueous solution of hexamethylenediamine salts of terephthalic and isophthalic acids (6TA and 6IA salts) in an autoclave under controlled time, temperature and pressure conditions Heated and formed a molten 6TA / 6IA polymer

709821 / 10Ö0

then extruded into fibers immediately from the bottom of the autoclave will. The fibers are essentially amorphous and become stretched and tempered to increase crystallinity and improve strength properties. A minor one The amount of 6TA / 6IA polymer remains as a coating on the inner wall and the stirrer of the autoclave after extrusion. Unfortunately This 6TA / 6IA polymer coating does not melt completely during the next polymerization. Particles of 6TA / 6IA polymer coating disperse in the melted 6TA / 6IA polymer formed in the next polymerization becomes, with the formation of a heterogeneous 6TA / 6IA polymer, a condition referred to herein as "polymer catheterogeneity" will. Attempts to obtain useful fibers by melt spinning heterogeneous 6TA / 6IA polymers, are not entirely successful and in some cases can Fibers are not preserved at all. In the cases where fibers are obtained, the fibers are in appearance opaque, contain particles of considerable size, and generally have unacceptable properties. It is therefore, in order to obtain high quality fibers, the Clean the autoclave between each working period (i.e. polymerisation and extrusion) in order to remove the 6TA / 6IA polymer coating to remove that remains after extrusion. The cleaning of the autoclave after each operation is essential time consuming and expensive and therefore not suitable for technical purposes.

It is an object of the present invention to provide a modified

709821/1000

to create adorned fiber-forming 6TA / 6IA polymer preparation, which can be prepared by a batch process in an autoclave without sacrificing polymeric catheterogeneity occurs and without the autoclave between the one another the following working periods to remove the polymer coating needs to be cleaned.

Another object of the invention is a modified OTA / eiA polymer preparation from which useful fibers are formed can be produced.

According to the present invention, the melt polymerization of 6TA and 6IA salts in the presence of one or more Hexamethylene diamine salts of an aliphatic dibasic

0 0

Acid of the general formula HO-C-R-G-OH, in which R is an alkylene group having 3 to 10 carbon atoms to form a Copolyamids, which are essentially the repeating Units of the formulas

(A) -NH - £ - CH ₂ - ^ HH-Ö- <

(B) -NH

(C) -NH-f-CH

contains, wherein R is a C, - to C ^ Q -alkylene group and in the successive (C) units, identical or different

709821/1000

is and where 30 to 40 # of the repeating units (B) units, 2 to 15 # of the repeating units (C) units and the rest of the repeating units are (A) units.

The copolyamides of the invention can be prepared and extruded from an autoclave by a batch process without polymer catheterogeneity occurring and without leaving the autoclave between process sequences be cleaned to remove the polymer deposits got to.

The fibers of the invention made from the copolyamides are normally essentially amorphous and can be processed by annealing processes, as described in the British patent, annealed to increase their crystallinity will. Annealing can be accomplished either during or after the fibers are drawn as they are spun (i.e., stretched) at a desired orientation and denier. While stretching the fibers like them obtained by spinning leads to an orientation of the polymer molecules in the direction of the fiber axis drawing without annealing does not significantly increase the crystallinity of the fibers after the state of spinning. Crystalline fibers made from eTA / eiA / GRA polymers of the invention have shrinkage values in boiling water of less than about $ 10 and it's with them many of the best properties of both nylon 66 and PET (polyethylene terephthalate) fibers combined. For example

709821/1000

the crystalline fibers have an adhesion to rubber and color retention properties that they have with nylon 66 fibers, and moduli and crease resistance that make them comparable to PET fibers do.

The 6TA / 6IA / 6RA polymers of the invention can be prepared by melt polymerization of a salt mixture containing the appropriate amounts of 6TA salt, 6IA salt and 6BA salt, for which purpose an aqueous solution of the salt mixture in an autoclave in a conventional manner controlled time, temperature and pressure conditions. The polymerization is preferably carried out in three stages. During the first section, the reaction mixture is heated in the presence of an inert gas such as nitrogen from room temperature to about 20O ⁰ O under a pressure of about 18 atm. During the second section, the reaction mixture is heated to about 300 ^° C., the pressure being kept essentially constant. During the third section, the temperature is increased slightly, for example by a further 10 to 20 ^° C., while the pressure is reduced to atmospheric pressure. If necessary, after the end of the third stage, the molten mass obtained is kept at atmospheric pressure at or above its melting temperature for a sufficient time to bring the molten mass to equilibrium, for example 30 minutes. The optimum time, temperature and pressure conditions which come into consideration for carrying out each of the polymerization sections become somewhat dependent on the melting point of the respective 6TA / 6IA / 6RA polymer intended for production

709821/1000

vary. The obtained molten 6TA / 6IA / 6RA polymer can be extruded through a spinneret attached to the bottom of the autoclave, essentially producing amorphous fibers. Further processes can be carried out in the autoclave without removing the polymer residues from the autoclave between successive Process removed and without any polymer catheterogeneity entry. The fibers obtained are then used to increase crystallinity and otherwise improve their physical properties to improve, stretched and tempered.

The annealing of the substantially amorphous fibers can be carried out during drawing or after the fiber has been adjusted to a desired one Denier drawn. In general, the fiber is drawn to 3 to 5 times its initial length. If the fiber is drawn before annealing, it can be passed through a heated mandrel (85 to 115 ° C). The stretching of the essentially Amorphous fiber without annealing leads to an orientation of the polymer molecules in the direction of the fiber axis, but increases does not significantly affect the crystallinity of the fibers. However, if after drawing the substantially amorphous fiber in is annealed in the manner described herein, the fiber has a relatively high degree of crystallinity. Annealing the fiber is expediently carried out so that the fiber is heated to a temperature above the glass transition temperature (Tg) of the Polymerisats and below the temperature at which the fiber is melted, and preferably to a temperature above

709821/1000

/ ο

about 160 ⁰ G heated. Annealing of the fibers can be accomplished by exposing the fiber to a heated environment such as a heated inert liquid (e.g., steam, air or nitrogen) or a heated surface such as a hot shoe. A preferred method of heating the fiber is by continuously passing the fiber through an electrically heated tube with a cushion of steam or heated nitrogen. Another method is to continuously pass the fiber through a chamber equipped with an infrared heater or over a heated curved surface. If desired, the fiber can simply be placed in an oven and heated. The length of time that the fiber is brought into contact with the heated environment depends on factors such as the temperature of the heated environment and the denier of the fiber. Various methods and conditions known to those skilled in the art can be used to anneal the fibers of the invention.

It was found that the physical properties of the annealed fibers can be affected by the tension of the fibers while they are undergoing annealing. For example, have stretched fibers that are held loosely during annealing, minimal shrinkage values in boiling water (BWS), for example below 2 #, while drawn fibers held under considerable tension during annealing (for example if they are further stretched at a stretching ratio of 1.12 to 1.2 during annealing) generally BWS

709821/1000

Values between 8 and 10 #. It will be stretched accordingly Fibers, if they are subject to intermediate stresses during annealing, have BWS values of 2 to 8 #. The strength of the Fibers, on the other hand, is directly proportional to the amount of stress the fibers are subjected to during annealing. Fibers, that are subject to tension during annealing accordingly have greater strength than fibers that are held loosely during annealing will.

Salt mixtures that are used to produce the 6TA / 6IA / 6RÄ.-polymers of the invention contain 30 to 40 moles. # 6IA salt and 2 to 15 moles. # 6RA-SaIz with the remainder being 6TA-SaIz. The molar ratios of the 6TA, 6IA, and 6RA units in the polymers obtained agree with the corresponding molar amounts of 6TA, 6IA and 6RA salts used for their preparation were used.

To effectively avoid polymer heterogeneity, the salt mixture must contain at least about 2 moles of # 6 RA salt. if on the other hand, more than about 15 mol. # of the salt mixture of 6RA-SaIz insist, the shrinkage values will be in boiling water and adversely affects the strength properties of the fibers produced from the resulting polymers. Satisfactory Results are generally obtained when 7 to 12 mol. # Of the for the preparation of the polymers according to the salt mixture used in the invention consist of 6RA-SaIz. Generally when more than about 40 moles. # Of the salt mixture consist of 6IA-SaIz, the fibers produced from the polymers obtained are difficult to crystallize, while

709821/1000

if less than about 30 moles. # of the mixed salt of 6IA salt exist, it is difficult to laser from the polymer obtained because of the high melting point of the polymer obtained to build.

About 6EA salts used to make the copolyamides of the invention are suitable include the hexamethylenediamine ores Glutaric, adipic, azelaic, cork, sebacic or dodecanedicarboxylic acids. If desired, a mixture of two or more can be used 6RA salts can be used. Hexamethylene diammonium adipate (66-salt) is a preferred 6RA salt used in the manufacture of Polymers according to the invention is used.

The salts that are used to produce the polymers should and can have the highest possible purity be produced by conventional processes, as are usually used for the production of simple polyamide salts, for example, hexamethylene diammonium adipate (66 salt) is used will.

The following examples serve to illustrate the invention without restricting the scope of the invention.

The tensile strength properties of those given in the examples Pipes were measured using an Instron tester. The intrinsic viscosity values (η) used in the examples are defined by the following equation:

) = V 'd (.RV-I-InRV ) , C

709821/1000

265-534

where EV is the relative viscosity and G is a concentration of 0.4 g of polymer in 100 ml of solvent. The relative viscosity is determined by dividing the flow time of a dilute solution of the polymer by the flow time of the pure solvent in a capillary viscometer. The diluted solutions used for determining the RV value are the concentration expressed by (G); the flow times are determined at 25 ° C. using 95 to 98% concentrated sulfuric acid as the solvent. The percentage values of shrinkage in boiling water (.% BWS) are determined in the examples using the following procedure. Two clips are attached to the length of the fiber (L-,) so that the distance between the clips when the fiber is stretched is 15 and 50 cm. The fiber secured with the clamps is then immersed in boiling water for 10 minutes. The fiber is then removed and dried under room conditions. The distance between the clamps when the fiber is stretched is measured again (L ₂ ). The percentage of shrinkage in boiling water (BWS) is determined according to the following equation:

BWS = ( ^L 1 " ^L 2 \ χ 100

^L 1

example 1

This example illustrates the production of 6TA / 6IA / 66 (60 / 3 5/5) polymer is at, i.e. a 6Q} A / 6IA / 6RA polymer that Moles. # 6TA units, 35. Mole # 6IA units and 5 mole # 66 units contains and melt spinning into a yarn.

709821/1000

90.0 g (0.3188 mol) of 6TA salt, 52.5 g (0.1859 mol) of 6IA salt, 7.0 g (0.026 mol) of 66 salt and 100 g of deionized water are placed in an autoclave made of stainless steel. After the autoclave and its contents have been thoroughly flushed with nitrogen, the autoclave is pressurized to 18 atm with nitrogen. away. It is then heated for 25 minutes while stirring the autoclave at 220 ⁰ G and maintains the pressure constant at 18 atm. One then raises the temperature to 300 ⁰ G for 27 minutes with the pressure being in turn at 18 atm. holds. One then reduces the pressure to atmospheric pressure for 25 minutes while the temperature is raised to 316 ⁰ C. At the bottom of the autoclave there is a 14-hole nozzle and the polymer (/ *? _ 7) = 0.824-) was then passed through the spinneret using a nitrogen pressure of 18 atm. extruded. The resulting yarn was collected on a bobbin using a conventional winder. The yarn was then stretched by 3.60 times with a 2 "(50, £ 3 mm) pin at 100 ⁰ C to give an 80 the yarn having an elongation of 18 # and a strength of 3.8 g / the, received.

Example 2

This example explains the production of 6TA / 6IA / 66- (60/30/10) polymer (/ r \ 7) - 0.81) and the melt spinning into a yarn. The polymer and yarn were made according to the procedure of Example 1. In this case the polymer was prepared from a mixture of 6TA-j 6IA and 66 salts, the salts being used in a molar ratio of 60:30:10. The yarn was collected and then around that

709821/1000

is

Drawn 3.7 times to 80 denier. The drawn yarn had an elongation of $ 18 and tenacity from 3 »7 g / den.

Example 3

This example explains the production of 6TA / 6IA / 66- (55/35/10) polymer (/ ^ _ 7) = 0.80) and the melt spinning into a yarn. The polymer and yarn were made according to the procedure of Example 1. In this case the polymer was prepared from a mixture of 6! A- * 6IA and 66 salts, the salts being present in a molar ratio of 55-135-10. The yarn was collected and drawn 3 »95-S ¹ to a denier of 71. The drawn yarn had an elongation of 16 $ and a tenacity of 3-7 g / den.

Example 4

This example explains the production of 6TA / 6IA / 66 (50/35/15) polymer and melt spinning into a yarn. The polymer and yarn were prepared according to the procedure of Example 1, in this case the polymer was prepared from a mixture of 6TA, 6IA and 66 salts, the salts being present in a molar ratio of 50: 35 * 15. The yarn was collected and ^shed 3-80 JL by 74 den. stretched. The drawn yarn had an elongation of 20 # and a tenacity of 2.8 g / den.

709821/1000

Λ,

Example 5

A sample of each of the yarns of Examples 2 "to 4- was annealed, for which purpose the yarn was passed continuously at a constant length (draw ratio 1.0) and a speed of J8.1 m / min, through a chamber with a length of 30, 5 cm is derived, containing the infrared heaters. the chamber was maintained at a temperature of about 30O ⁰ C. for comparison, a 70 is the. 14-j? adengarn made of 6TA / 6IA- (65/35) as well under the same conditions annealed The # value BWS for each of the yarns was determined before and after annealing and is given in Table I below.

Table I. # ESPE after the
Annealing Molar nursing care
6TA / 6IA / 66 % GVA before
Annealing 6.6 65/35/0 22.0 5.6 60/30/10 22.2 8.7 55/35/10 21.9 9.5 50/35/15 38.7

The results in Table I show that from the polymers Yarns made according to the present invention can be annealed to form dimensionally stable yarns which are comparable to the annealed yarns made from 6TA / 6IA polymers.

Example 6

This example illustrates that fibers of the polymers of the present Invention made in an autoclave in batches

709821/1000

can be without having to intervene in the autoclave following polymerizations cleans to remove polymer deposits from the autoclave and without a Polymeris catheterogeneity occurs. In the batch process, two sequential polymerizations were carried out, without cleaning the autoclave after the first process run. A mixture of 6TA-, 6IA and 66 salts in the autoclave to form the molten Polymerized. The molten polymer was then extruded from the bottom of the autoclave into water, obtained and, as far as possible, melt-spun into yarn.

6TA / 6IA / 66 (55/35/10) polymer was prepared by adding 825 g (2.922 mol) 6TA salt, 525 g (1.859 mol) 6IA salt, 140 g (0.534 mol) 66 salt and Introduces 1000 g of H ₂ O into a cleaned autoclave. After thorough cooling with purified nitrogen, the autoclave is closed and heated to 200 ^° C. while stirring and the pressure to 14.6 atm. increases. The temperature and pressure were then kept constant for 15 minutes. The temperature was then increased to 218 ^° C. over the course of 3 minutes, the pressure being increased to 18 atm. increases and keeps it constant. The temperature was then increased to 300 ^° C. (18 atm.) For 30 minutes. The pressure was then reduced to atmospheric pressure for 65 minutes while increasing the melting temperature to 32O ⁰ C. The polymer was then extruded from the autoclave and quenched in water. The extruded polymer mass was pure and homogeneous. After the extrusion, about 150 g of polymer remained in the autoclave as a covering

709821/1000

2851534

the walls and the agitator. A second polymerization was carried out in the autoclave in the presence of the polymer deposit performed using essentially the same procedure and the same conditions as used in the first polymerization. The extruded polymer mass was clear, homogeneous and could easily be melt-spun into a yarn. After the second polymerization there were again about 14-5 g polymer after extrusion in the autoclave.

For comparison purposes, 6TA / 61A (65/35) polymer was prepared in such a way that 975 g (3.4-53 mol) of 6TA salt, 525 g (1.859 mol) of 6IA salt and 1000 g of H ₃ O in introduces a cleaned autoclave. The polymerization was carried out using essentially the same procedure and conditions as above. About 145 g of the polymer obtained remain in the autoclave after extrusion. A second polymerization was then carried out in the autoclave in the presence of the polymer deposit using essentially the same procedure and conditions as the first polymerization. The extruded mass obtained contained lumps of white, opaque material which was dispersed in the clear polymer matrix, ie the polymer mass was heterogeneous. This heterogeneous property prevented the polymer from being melt-spun into a yarn.

The preceding examples illustrate that the modified 6! EA / 6IA polymers of the invention can be prepared without polymer catheterogeneity occurring and that they

709821/1000

^ L

sern can be melt-spun, which after annealing essentially have the same properties as tempered 6TA / 6IA fibers. A major advantage of the polymers Invention over the 6TA / 6IA polymers consists in that the polymers of the invention batch in an autoclave can be produced without the autoclave having to be cleaned after each polymerization. In contrast to When producing the 6TA / 6IA polymers in a batch-wise autoclave, the autoclave must be cleaned after each run to avoid polymer catheterogeneity. Cleaning the autoclave after each process is time consuming and costly and cannot be tolerated for technical purposes.

While polymers prepared from 6TA, 6IA and 66 salts were illustrated in the preceding examples, similar results can be obtained if the 66 salt is replaced by an equivalent molar amount of another hexamethylene diamine salt of a G ₁ - to C ^ o-eicarboxylic acid, for example glutaric, cork or dodecanedicarboxylic acid or mixtures thereof replaced.

In summary, the present invention relates to manufacturing of fiber-forming polymers from a mixture of hexamethylene diamine salts of terephthalic acid and isophthalic acid and a minor amount of at least one aliphatic dibasic Acid (e.g. adipic acid) having 5 to 12 carbon atoms. The polymers can be used in batches in a car

70 9 8 2 1/1000

claves are produced and extruded therefrom without having to run the autoclave according to the respective process cleans.

-Patent claims-

709821/1000

Claims (6)

Patent claims: 1. Fiber-forming copolyamide, with random, disordered Ver division, characterized by the following units (A) -NH CH (B) -NH CH NH-C It NH-C It σ (C) -NH CH ο ο ti Il UH-C-R-C- in which R is a C - to C ^ ₀ -alkylene group and in the successive (C) units is the same or different and in which 30 to 40 $ of the recurring units (B) units, 2 to 15 ^ of the recurring units ( C) units and the rest of the repeating units are (A) units. 2. copolyamide according to claim 1, characterized in that that $ 7 to $ 12 of recurring units (C) units are. 3. Copolyamide according to claim 1, characterized in that R £ - CH ₀ ~) τγ is. 4. copolyamide according to claim 1, characterized 709821/1 indicates that it is in the form of a fiber. 5. copolyamide according to claim 1, characterized that it is in the form of an annealed fiber with a boiling water shrinkage value that is lower is than about $ 10. 6. copolyamide according to claim 6, characterized in that R - £ - CH ₂ -) τγ is. 709821/1000