DE758619C - Process for the production of polyamides - Google Patents

Description

It is known that polyamides using diamines or dicarboxylic acids, their carbon chain by one or more Heteroatoms is interrupted, has been produced »iodine. It is also known that one can Mixed polyamides ,, d. H. produce them from several raw materials. The under mark usage of diamines or dicarboxylic acids, their carbon chain through oxygen atoms is interrupted, produced polyamides are in contrast to those; whose starting materials do not contain oxygen atoms in the Contains carbon chain, very soft, relatively good in organic solvents, and to a considerable extent also in Water soluble and melts relatively low. Because of their low melting point and water sensitivity, they have not yet acquired any practical importance.

It is also known that polycondensation products have been prepared from α, / ^ - unsaturated monocarboxylic acids and diamines, including those whose carbon chains are interrupted once or several times by heteroatoms or groups containing heteroatoms. Mixtures of different diamines can also be used. Although these polycondensation products represent high molecular weight polyamides, they are similar to the polyamides as they are

saturated dicarboxylic acids or mixtures these are not comparable in their properties. They generally own have a much lower molecular weight than those and are, with a low degree of condensation still viscous, resin-like substances with a slightly higher degree of condensation, and when condensing under very severe conditions, which generally lead to particularly ίο high molecular weight substances are obtained Products that, in contrast to the well-known polyamides, already have a strong cross-linking exhibit, which is noticeable in poor solubility and low mechanical strength. 5 bar makes.

It has now been found that polyamides of satisfactory water resistance and good mechanical properties and thus versatile practical usability from dicarboxylic acids and diamines and / or aminocarboxylic acids or amide-forming derivatives of these substances are obtained if starting materials with a continuous carbon chain and up are obtained in the 1 condensation about 10 per cent; ^a 5 of the weight of these substances in diamines, whose carbon chain is divided by two ^! or more oxygen atoms are interrupted. One can use the known superpolyam-forming starting materials, for example to · »/ -dicarboxylic acids and ω ·« / -diamines | or ( "amino carboxylic acids whose carbon chains are i material not interrupted or amide '■ forming derivatives of these substances, eg., esters, anhydrides and lactams, as well as mixtures of these substances apply. Particularly ^valuable! polyamides obtained when one uses mixtures of adipic acid hexamethylenediamine and ε-caprolactam in the ratio 40:60 to 60:40 ^! and also up to about 10% diamines whose carbon chains are interrupted by 2 or more oxygen atoms: one must use the last-mentioned diamines ! about equimolecular amount of dicarboxylic acids medium-use, otherwise ER- only relatively low molecular weight ^condensates: will hold.

Suitable diamines whose carbon chain is interrupted by 2 or more oxygen atoms are in particular those of an aliphatic nature, e.g. B. Ethylene glycol-di - /? - amino <ethyl ether, ethylene glycol-di-j'-aminopxopyl- _; ether, ethylene glycol di-d-aminobutyl ether, propylene glycol di-jÖ-aminoethyl ether, -j> -a- ■ minopropyl ether, -o-aminobutyl ether, 1 · 4-butanediol-di - ^ - aminoethyl ether, -j'-aminopropyl ether, - <5-aminobutyl ether, also di- or tri- ■ ethylene glycol - to - γ - am inop ropy lather and also Ät'hyleneglykol-di-p-ammophenylether.

The condensation is carried out in the usual way for polyamide production. It can be carried out under increased, normal or reduced pressure. Often is the initial application of pressure beneficial. To avoid discoloration of the polyamides, the condensation is expediently carried out with the exclusion of oxygen. By addition small amounts of excess dicarboxylic acids or diamines or monocarboxylic acids or monoamines can be the formation of condensation products with respectively achieve desired molecular weight.

The amount in which the diamines, their carbon chain through 2 or more oxygen atoms is interrupted, are used, depends essentially on the nature of the other starting materials and the desired Properties of the final products ah. Even very small amounts are sufficient, e.g. B. a Addition of 5% adipic acid ethylene glycol di-7-aminopropyl ether to a mixture of approximately equal parts of adipic acid hexamethylenediamine and ε-caprolactam to obtain a polyamide used in ordinary Temperature in 80 ° / odgem aqueous methanol or ethanol gives clear, stable solutions, while the polyamides are made from equal parts of adipic acid hexamethylenediamine and f-caprolactam only give clear solutions in hot aqueous methanol or ethanol, when these solutions cool, gelation occurs. By using the diamines whose carbon chain is interrupted by 2 or more oxygen atoms, a better solubility of the polyamides is always achieved. It is surprising that already relatively small amounts of these diamines exert such an effect. on the other hand However, the polyamides obtained in this way still have sufficient water resistance. Only when these diamines are added more than 10% does the water resistance decrease significantly, so that the practical utility of such polyamides for many purposes is impaired. . The polyamides obtainable according to the invention have yet another noteworthy one and surprising property. In contrast to the polyamides known up to now, threads, even thicker threads, are made from them a rough surface after stretching, which is desirable for many purposes. These too Effect is already through the use of a relatively small amount of diamines, whose carbon chain by at least 2 oxygen atoms is interrupted, the condensation is achieved.

B e i s ρ i e 1 1

900 parts of hexamethylenediamine adipate, 900 parts of f-caprolactam, 200 parts adipic 1 ^ -Butanediol-di-j'-amhiopropyl-

ether, 5.03 parts of adipic acid and 600 parts of water are aufgelheizt in a pressure vessel made of stainless steel in the absence of air within 2 hours at 278 ⁰ ', the pressure by venting of the corresponding quantities of water vapor at 17 is maintained at up to 18th Then, at the same temperature, the pressure is slowly released over the course of 1½ hours and the whole is kept at this temperature for 1½ hours at atmospheric pressure. When the polyamide obtained in this way is pressed into water through an opening in the bottom of the pressure vessel, a firm but soft product is obtained which, in 80% aqueous methanol or ethanol, provides solutions with a solids content of about 20% at normal temperature stay clear when standing for a long time.

The superpolyamide can be processed into threads and strings in the usual way. These have a rough surface after stretching.

■ Example 2

180 parts of adipic acid hexamethylenediamine, 180 parts of ε-caprolactam, 18 parts of adipic acid ethylene glycol - di - γ - aminopropyl ether, 0.97 parts of adipic acid and 120 parts of water are treated in the manner indicated in Example 1. You also get a. Polyamide, which at ordinary temperatures provides clear and stable solutions, as well as threads and strings with a rough surface. Polyamides which are clearly soluble in the usual solvents at ordinary temperatures are also obtained in a corresponding manner with other diamines whose carbon chain is interrupted by 2 or more oxygen atoms.

Example 3

170 parts of ε-caprolactam, 1780 parts of adipin-. acidic hexamethylenediamine, 50 parts of adipic acid 1 · 4-butanediol-'di ^! -y-aminopropylether, 27.24 parts of 25% strength acetic acid and 1100 parts of water are treated in the manner indicated in Example 1. One receives a. Polyamide that can be spun into threads in an excellent way. After stretching, these have a very roughened surface.

Example 4

1950 parts of ε-caprolactam, 50 parts of adipic 1 · 4-butanediol ^ d'i-y-aminopropyl ether, 31.65 parts of 100% hydrochloric acid and 600 parts of water are placed in a stainless steel pressure vessel with the exclusion of oxygen within 2 Hours heated to 279 ' ⁰ , the pressure being kept at 15 atm by releasing the appropriate amounts of water vapor. Then, at the same temperature, the pressure was ^{slowly released within 1} 1/2 hours and the whole thing was kept at this temperature for an hour at atmospheric pressure and for 1/2 hour at 6 mm Hg pressure. A polyamide is obtained which can be processed excellently into threads and strings. After stretching, these have a rough surface.

Polyamides with similar properties are also obtained when other polyamide-forming ones are used Substances such as B. adipic acid decamethylenediamine, sebacic acid hexamethylenediamine, sebacic acid decamethylenediamine, nonanedicarboxylic acid hexamethylenediamine or mixtures of these.

Example 5

1100 parts of adipic hexamethylenediamine, 800 parts of ε-caprolactam, 39.8 parts of adipic acid, 72 parts of triethylene glycol bisv-aminopropyl ether (H ₂ N · CH ₂ CH ₂ CH ₃ · O (C Hj) ₂ O (C Hg) ₂ O ( C Hj) ₈ OCH ₂ CH ₂ CH ₂ -NH ₂ ) and 1000 parts of water are condensed in the manner indicated in Example 1. A soft polyamide is obtained which is readily soluble in methanol, 80% strength aqueous methanol or methanol-chloroform-water mixtures and which, despite its many oxygen bridges, still has good water resistance.

Is used instead of triethylene glycol bisy-aminopropyl ether the corresponding diethylene glycol bis-γ-aminopropyl ether, a similar condensation product is obtained in this way.

Claims (1)

Claim: Process for the production of polyamides by condensation of dicarboxylic acids and diamines and / or aminocarboxylic acids or amide-forming derivatives of these substances, characterized in that that in the condensation of the starting materials with a continuous carbon chain up to about 10% diamines are also used, their carbon chain interrupted by 2 or more oxygen atoms. To differentiate the subject matter of the invention from the state of the art are in the granting procedure the following publications have been considered: French patents nos. 826 070, 849 348. 1 5626 12.52