CS215443B1 - A method for preparing antistatic polyamide-6 - Google Patents

Abstract

A method of preparing antistatic polyamide-6 by simply incorporating a modifier into the polymer while maintaining the desired modifying effect. The modifier is the reaction product of a mixture of diaminopolyethylene glycol with dicarboxylic acid (C 4-12) or its ester and other components such as caprolactam or aminocaproic acid, stabilizers and molecular branching agents. Before hydrolytic polymerization, 1 to 6% by weight is added to the monomer. mixture of pre-polycondensate of the basic components and unmodified other components of the polyetheramide type modifier, whereby the pre-polycondensate consists of diaminopolyethylene glycol, dicarboxylic acid or its ester and any admixture of parts of the other components of the modifier in an amount up to 8% by weight. to its total amount and the hydrolytic polymerization is carried out in the presence of a prepolycondensate from these components.

Description

3

It is an object of the present invention to provide a process for the preparation of polyamide-6 polyamide fibers.

Antistatic modification of polyamide and general synthetic fibers is made to reduce electrostatic charge propensity and thereby improve their physiological properties. Such an effect can be achieved by the addition of some of the so-called polar group modifiers to the polymer mass used to prepare the fibers.

The properties of the modifiers and the method of incorporating them into the polymer, in addition to providing the desired antistatic properties of the polyamides and polyamide fabrics, must meet other requirements, in particular the durability of the modifying effect, the good processability of the modified polymer, do not substantially impair the mechanical properties of the products, deteriorate them. color properties and i.

Among the substances with antistatic modification effects, which have gained industrial application in view of the limitations of the above-mentioned requirements, are those which utilize the antistatic properties of polyglycols and especially their various, predominantly functional derivatives. Among the modifiers of this type, polyetheramides, which are formed by copolycondensation of diamine polyethylene glycols, dicarboxylic acids, polyamide-forming divalent substances and other admixtures, are significant.

Modified polyamides and polyamide products with the addition of polyetheramides, as modifiers, have very good antistatic properties and good resistance to loss of these properties, especially resistance to modifier scuffing.

Despite these advantages, the presently disclosed processes for the preparation of modified polyamides and polyamide products with the addition of polyether amides as modifiers are more deficient, especially in their technology.

The preparation procedures described so far are based on the requirement of preparing an intimate polymer blend with a polyether amide modifier such that melt of both components are mixed in suitable mixing devices, or the mechanical blend of the granules of the two components is melted at temperatures above their melting points. In spite of their technical feasibility, the two approaches are seriously problematic in a technological application.

The first method can be carried out by melting the modifier immediately after its preparation and cooling with the polyamide melt. That is, both the preparation of the modifier and the modified polyamide are bound to one another both temporally and locally.

In addition, this process requires a special device to maintain, transport, dispense the hot melt of the modifier, and mix it with the molten polymer.

The second method requires the preparation of modifier 215443 in the form of granulate. However, the granulation of the modifiable composition is difficult and hitherto unresolved due to its tackiness.

Alternatively, the preparation of the modified polyamides in such a way that the polyether amide modifier, or its starting non-modified components, is added to the starting monomers prior to their polymerization and / or polymerization. polycondensation, according to the prior art, is believed to be unsatisfactory. Despite some differences, the addition of the finished polyether amide modifier, so far described and claimed, to the monomer has similar difficulties to its addition to the polymer.

The admixture of the individual modifiers or their physical mixture to the monomer prior to the polycondensation is avoided because in this case the antistatic effect is poor. j

It is explained that in such a case, a sufficient mobile block copolymer modifier and a suitable ratio of polyether and polyamide segments will not be obtained, but that the polyether amide molecules are firmly embedded in the poles, avoiding the desired mobility and the possibility of forming a spatially related polyether arrangement. cells in the polymer mass.

Despite these limitations, a simple process for the preparation of a modified polyamide has been elaborated, which uses the analogy of the last method, i.e., admixing the modifier components to the monomer prior to polymerization. For this method of preparation of the modified polyamide, however, pre-treated - pre-treated condensation components of the modifier are to be used. and

It has been found that a preferred process for the preparation of 1 to 6 wt. polyetheramide, which is the reaction product of the mixture 40-85% wt. diaminoopo-! lyethylene glycol with an average mol. a weight of 600-4000, or a dicarboxylic acid; the ester in an amount of 1 to 1.2 equivalents to the use of diamino polyethylene glycol and other components such as ε-caprolactam, or ε-aminocaproic acid, stabilizers, branching agents, and the like, is a method by which monomer? % hydrolysis polymerization adds 1-6 wt. mixtures of pre-polycondensate base components and unmodified other components of the polyether amide modifier, wherein the prepolycondensate is comprised of diaminopolyethylene glycol, dicarboxylic acid or an ester thereof, and optionally other components of the modifier in an amount of up to 8% by weight. its total quantity.

The actual hydrolytic polymerization of ε-caprolactam is carried out in the presence of a prepolycondenate from these components.

The contemplated prepolycondensate composition follows the requirement of its fusibility at relatively low temperature. 4

Ingredients which, assuming that they are pre-polycondensated, increase the melting of the prepolycondensates, can be added as a physical additive to the pre-polycondensation modification mixture and prior to its addition to the monomer. The presence of the components of the reaction mixture to form the modifier in the monomer mix does not require substantial modifications to the prepolymer process.

The proposed process for the preparation of modified polyetheramide-containing polyamides has a number of advantages to the presently proposed process.

In particular, it allows incorporation of the modifier into the polymer by mixing a mixture of its pre-treated starting components with the starting monomer prior to polymerization. polycondensation without the risk of immobilization of the active ingredients of the polymer modifier, i.e. without the risk of loss of antistatic efficacy.

The process makes it possible to mix the modifying resin with a monomer or add it to the molten monomer at relatively low temperatures. It eliminates the need for both time and local continuation of modifier and modified polyamide preparation.

It allows the preparation of modified polymers without the construction of technically demanding auxiliary equipment to production lines for polyamide production.

Critical danger of loss of modifier efficiency when introducing a mixture of its starting materials into the monomer prior to polymerization. The polycondensation is removed by introducing the modifier active ingredient into the reaction mixture in the form of its low reactive prepolycondensation with the appropriate acid. This prevents it from being chemically completely incorporated into the molecules of the resulting polyamide.

Moreover, the advantages of the proposed process are practically a favorable consequence of the fact that the mixed components for the preparation of the modified polymer, i.e. monomers and modifier components, can be melted at relatively low temperatures - by the melting temperature of the monomer.

The processing of the polyamide of the present invention into polyamide molded articles does not differ significantly from the treatment of untreated polyamide. However, the products have higher utility values.

A method for preparing modified polyamide polyamide products according to the present invention demonstrates without limitation the following examples. EXAMPLE 1 4% of a prepolycondensate mixture of 1.6 kg of α-, ω-diamino polyglycol with 160 g of adipic acid and 6 g of triphenyl phosphite admixed with 600 g of ε-aminocaproic acid was added to ε-caprolactam monomer before polymerization. This gave rise to a 215443 disc mixture for the preparation of the modified polyamide. This was subjected to the addition of additional impurities required for hydrolytic polymerization, such as water and benzoic acid, to polymerize the running conditions - a temperature of about 254 ° C and a heating time of about 6 hours. The polymerization of the polyamide and the polycondensation of the modifier took place simultaneously. The result was a modified polyamide with a relative viscosity of η = 2.28 dl / g. The prepared modified polyamide was granulated. The granulate was used for spinning after drying. Grate spinning was performed using a 12-hole nozzle at 275 ° C and a discharge rate of 1400 m / min. The fibers owed cold at a ratio of 1: 2.68. The prepared polyamide modified binder had a strength of 4.6 cN / dtex, a ductility of 38%, an increased wetness, and an electrostatic charge value below 30% of the electrostatic charge of the unmodified polyamide fibers. Example 2

The modified polyamide prepared in Example 1 was spun in a small amount on an experimental screw 16 with a 20-hole nozzle of 275 ° C and a spinning speed of 270 m / min. The fibers were cold at a ratio of 1: 3.5. The fibers had a strength of 4.3 cN / dtex and a ductility of 24%. Example 3

The procedure was similar to that of Example 1, except that caprolactam was used instead of ε-aminocaproic acid in the starting mixture of modifier. This change increases the flowability of the melt blend and facilitates handling. The results with respect to the process of preparing the modified polyamide, its properties, the fiber conditions and the fiber properties are practically the same as those of Example 1. Example 4

In the preparation of the modified polyamide, the co-modifying agent used alone was polycondenate of α-, ω-diamino polyglycol, adipic acid and triphenylphosphite with the ratio of components as in Example 1, but without any additional impurities. A further procedure for preparing the modified polyamide and modified fibers and their properties was as in Example 1. Example 5

The procedure was similar to Example 1. However, the modification mixture was different. The prepolycondensate was prepared using a mixture of 1.6 kg of α-, ω-diamino-polyethylene glycol and 200 g of dimethyl terephthalate and 400 g of caprolactam was added to the flask. The processability of the modified polyamide and the resulting properties of the modified fibers were approximated by the example.

Claims (1)

Process for preparing antistatic polyamide-6, modified with an admixture of 1-6% wt. polyetheramide, which is the reaction product of a 40-85 wt. diaminopolyethylene glycol with an average mol. weight of 600-4000, dicarboxylic acid having 4-12 carbon atoms, or an ester thereof in an amount of 1 - 1.2 equivalents to the diamino polyethylene glycol used and other components such as ε-caprolactam or ε-aminocaproic acid, stabilizers, branching agents and characterized in that the? -caprolactam monomer is hydrolytic before its realization BACKGROUND OF THE INVENTION 1-6 wt. a mixture of prepolycondensate of the basic components and untreated other polyetheramide type modifier components, wherein the prepolycondensate is composed of diamino polyethylene glycol, dicarboxylic acid or an ester thereof and optionally admixing a portion of the other modifier components in an amount of up to 8 wt. to its total amount and the hydrolytic polymerization of ε-caprolactam is carried out in the presence of prepolycondensate from these components.