KR0150690B1 - Process for preparing polyurethane-elastic fiber having oxidation-resistance and heat-resistance - Google Patents

Abstract

It has at least one long-chain diol (A) and a tertiary amino group in which a polyether diol (A-1) having a number average molecular weight of 1000 to 2800 and a polycarbonate diol (A-2) having a number average molecular weight of 500 to 2500 are mixed. The polyol (B) having 1 to 7 amino groups and 3 to 12 carbon atoms is prepolymerized with the excess diisocyanate compound (C), mixed with a solvent and in a proportion, and then the diamine compound (D) as a chain growth agent is 0.60 to 0.98 mole is used, and monoamine (E) as a chain stopper is added so as to be 1 to 30 mole% of the total amount of amine, and polymerization is completed. Then, 0.05 to 4% by weight of antioxidant (F) is added to the polymer solids to give elasticity. Method for producing polyurethane-based elastic fibers having excellent oxidation resistance and heat resistance while maintaining their inherent physical properties.

Description

Method for producing polyurethane-based elastic fibers having excellent oxidation resistance and heat resistance.

The present invention relates to a method for producing a polyurethane-based elastic fiber excellent in antioxidant properties and heat resistance while maintaining the inherent physical properties of the elastic fiber, more specifically, a polyether diol having a number average molecular weight of 1000 to 2800 and a number average molecular weight After prepolymerizing with 1 to 7 amino groups, 3 to 12 carbon atoms, and diisocyanate having 1 or more long-chain diols and tertiary amino groups mixed with polycarbonate diols of 500 to 2500, the solvent and the ratio are mixed. It is related with the method for producing a polyurethane-based elastic fiber, characterized in that the isocyanate of chain growth using a diamine compound to obtain a suitable viscosity for spinning, and then the terminal is blocked using a monoamine compound and an antioxidant is added.

Polyurethane-based elastic fibers have excellent elasticity and elastic recovery rate, and are widely used in stretch fabrics such as stockings, women's underwear and swimwear.

However, polyurethane-based elastic fibers are limited in the use of elastic yarns because they cause oxidation by oxygen, resulting in deterioration of quality when used as a product. In addition, heat resistance is weak, so high temperature dyeing is impossible when mixed with other materials such as polyester fiber.

In order to remedy this drawback, many studies have been conducted so far.

For example, Japanese Unexamined Patent Application No. 61-67749 synthesizes a stabilizer having a molecular weight of 1000 to 50,000 with a hydroxyl group of 1 g × 10 ⁻⁴ moles or more of a polyurethane compound synthesized from a trifunctional phenol compound and a diisocyanate compound. It was added during the preparation of the polyurethane-based fiber to slightly improve the antioxidant properties. However, satisfactory physical properties could not be obtained, and it was difficult to expect not only a decrease in elastic modulus and elastic recovery rate, which are inherent in polyurethane fibers, but also improvement in heat resistance.

Accordingly, an object of the present invention is to provide a method for producing a polyurethane fiber, which significantly improves the oxidation resistance while maintaining the inherent physical properties of the polyurethane elastic fiber, suppresses oxidation reactions by oxygen in the atmosphere, and improves resistance to heat. To provide.

In order to achieve the above object as well as easily expressed results in the present invention, the diol compound composed of polycarbonate diol constitutes a long chain of the polymer, and the side chain of the polyol polymer having a tertiary amino group. To obtain a prepolymer having an excess of a diisocyanate compound forming a urea bond with a tertiary amino group, and then mixing it with a solvent in a proportion, and then adding a chain growth agent and a chain stopper to prepare a polymer having a suitable viscosity for spinning. After the addition of antioxidants to prepare a polyurethane-based elastic fiber excellent in antioxidant properties and heat resistance.

The present invention will be described in more detail as follows.

Diol compounds composed of polyether diols having a number average molecular weight of 1000 to 2800 and polycarbonate diols having a number average molecular weight of 500 to 2500, containing one or more tertiary amino groups, and having 1 to 7 amino groups and 3 to 12 carbon atoms And a diisocyanate compound to prepare a prepolymer, followed by mixing with a solvent at a predetermined ratio, and then adding a chain growth agent and a chain stopper to prepare a polymer suitable for spinning, and then adding an antioxidant to polyurethane Elastic fibers were prepared.

In the present invention, the long chain diol (A) constituting the soft segment of the polyurethane polymer is composed of polyetherdiol (A-1) and polycarbonate diol (A-2), the molar ratio (A-2 / A-1) is 0.3-10, especially 0.5-7, and after mixing the polyol (B) which has a tertiary amino group so that the molar ratio (A / B) with long-chain diol (A) may be 5-45 especially 12-35, Prepolymerization with 1.23 to 2.5 moles of 4,4'-diphenylmethane diisocyanate and an appropriate amount of dimethyl acetamide were mixed to prepare a prepolymer solution.Then, the diamine mixture was used to grow the terminal isocyanate using 0.60 to 0.98 moles of the prepolymer. To obtain 500-3,800 poises, which are suitable for spinning. Thereafter, the chain stop monoamine compound is chain-stopped by using 1 to 30 mol% of the total amine amount, and then a viscosity stabilizer is used to maintain an appropriate viscosity.

By adding 0.05 to 4% by weight of the phenolic compound polymer solids, which is an antioxidant compound, to the solution of the polymer, antioxidant properties and heat resistance are improved while maintaining the inherent physical properties of the elastomer.

As the polyether diol (A-1), polyethylene glycol, polypropylene glycol, polytetramethylene glycol, or the like may be used, and the molecular weight is suitably in the range of 1000 to 2800, particularly 1500 to 2500.

The polycarbonate diols (A-2) include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1 Glycols alone or mixtures thereof, such as, 4-cyclohexane diol, 1,4-cyclohexane dimethanol, 2,2-dimethyl-1, 3-propanediol, 1,8-octane diol, and diaryl carbonate, dialkyl For condensation reactions with carbonates, phosgenes, etc., synthesized diols having a molecular weight of 500-2500, especially 1000-2200, are used.

If the molecular weight and molar ratio of the above-mentioned polyether diol (A-1) and polycarbonate diol (A-2) are out of the range, there is a problem in steel, elongation and antioxidant resistance, heat resistance, etc., which are inherent properties of elastic yarns. Excellent performance is not obtained.

In addition, the polyurethane elastic fiber having at least one tertiary amino group having 1 to 7 amino groups and 3 to 12 carbon atoms of polyol (B) is used as a side chain at a position other than both ends of the tertiary amino group. By introducing, it has a network structure for urea bonding with isocyanate to form a strong bond, thereby improving heat resistance and elastic recovery, and improving viscosity stability of the polymer to maintain a suitable viscosity for spinning.

Examples of the polyol (B) component having the tertiary amino group include ethylene oxide, propylene oxide, and butylene oxide in primary amines represented by R-NH ₂ (R: C _n H _{2n + 1} , n = 1 to 30). Diols and derivatives thereof prepared by adding 2 to 60 moles of the back are used.

For example, N-methyl diethanolamine and N-ethyl diethanolamine obtained by adding 2 moles of ethylene oxide to primary amines such as methylamine, ethylamine, isopropylamine, n-butylamine and isobutanamine. Ethylene to alkylamines such as polyoxyethylene oleylamine in which 20 to 60 moles of ethylene oxide is added to N-alkyl diethanolamine such as N-isopropyl diethanolamine and laurylamine, stearylamine, and oleylamine. Diols to which an oxide, propylene oxide, etc. are added are used.

The molar ratio of the long-chain diol (A) to the polyol (B) having a tertiary amino group is preferably A / B = 5 to 45, particularly 12 to 35, and is less soluble in a solvent when the molar ratio is less than 5, which is not sufficient. After 45 seconds, the improvement in heat resistance and elastic recovery was insignificant.

Examples of the diisocyanate compound (C) which combines with an amine compound as a chain growth agent and acts as a hard segment include paraphenyl diisocyanate, metaphenylene diisocyanate, 2,4-torylene diisocyanate, and 2,6-tori Ethylene diisocyanate, 1-chloro-2,1-phenylene diisocyanate, 1,5-naphthalene diisocyanate, 1,4-phenylene diisocyanate, chlorphenylene-2,4'-diisocyanate, methylenebis 4-phenyl diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl diisocyanate, methylcyclo hexylene diisocyanate, paraphenyl diisocyanate, paraphenylene diisocyanate, 4,4'-diphenyl isopropylidine diisocyanate, 3,3'-dimethyl-4, 4'-difetyl diisocyanate, 3,3'-dimethoxy-4, 4'-dipetylene diisocyanate, 4,4'-diphenylmethane diisocyanate There are compounds of bytes, such as shown when considering the physical properties of the elastomer and reactive with the diol compound of 4,4'-diphenylmethane diisocyanate is best compound results.

The amount of the diisocyanate compound (C) is suitably C / (A + B) = 1.23 to 2.5 mol based on the compound (A + B) mixed with the long-chain diol (A) and the polyol (B) having a tertiary amino group. If it is less than 1.23 moles, the polymer is excellent in elongation but the strength is low and the elastic recovery ability is insufficient. If it is used more than 2.5 moles, the strength and elastic recovery rate are excellent, but the elongation is poor, resulting in the intrinsic physical properties of the elastomer.

The prepolymer obtained by combining the long-chain diol (A), polyol (B), and diisocyanate compound (C) is chain-grown by the diamine compound and chain-grown at a constant molecular weight, and then chain-stopped with monoamine to obtain a polymer having a suitable molecular weight. Can.

As diamine compound (D) which chain-grows a prepolymer, methyliminobispropylamine, 2, 5- dimethyl piperazine, 1, 2- propylene diamine, 2, 3- butylene diamine, meta styrene diamine, pyrazylene diamine , 2-methyl piperazine, ethylene diamine, ethanoldiamine, tetramethyl diamine, pentamethylene diamine, hexamethylene diamine, 1-methyl-2, 4-diamine benzene, 1,2-cyclohexane diamine, 1,3-cyclohexane Compounds such as diamine, 1,4-cyclohexane diamine, octamethylene diamine, paraphenylene diamine, and the like are used, and the range of use thereof is 0.6 to 0.98 mol% based on the prepolymer, which is required by the present invention. This is not obtained.

In order to improve the viscosity stability of the polymer in the chain growth compound and the properties of the elastic yarn after spinning, a linear amine and a cyclic amine should be mixed in an appropriate ratio.

The molar ratio (D-1) / (D-2) of linear diamine (D-1) and cyclic diamine (D-2) is in the range of 2 to 20, and when the molar ratio is less than 2, low molecular weight Since the polymer is produced, mechanical properties such as strength, elongation, and elastic recovery rate are lowered. If the molar ratio is more than 20, the reaction rate is too fast, and a large amount of side reactions are generated, thereby degrading the stability and heat resistance of the polymer.

Examples of the monoamine-based compound (E) which is a chain stopper for blocking the ends of the chain-grown prepolymer are monoethanol amine, diethanol amine, propyl amine, isopropylamine, diisopropyl amine, 2-ethylhexyl amine and di (2). -Ethylhexyl) amine, butyl amine, etc., considering the reactivity of the chain growth diamine compound isopropyl amine has excellent chain stop effect to maintain the molecular weight of the polymer moderately, and to inhibit the secondary side reactions Gives stability. The amount of isopropylamine used is 1 ~ 30% (mol%) of the total amine, and below 1%, the chain stopping effect is not only poor, and the viscosity is also severely changed over time, so the viscosity continues to rise, making it unsuitable for spinning. If it exceeds 30%, the chain growth of the polymer is prevented, so that it is not grown into a polymer having an appropriate molecular weight, so that a suitable viscosity for spinning cannot be obtained, and the physical properties, strength, elongation and elastic recovery rate of the polymer are poor.

Solvents for improving radioactivity by controlling the solid content of the polymer include dimethyl acetate, dimethylformamide, hexamethylphosphoramide, dimethylnitrosoamine, dimethylpropionamide, methoxydimethylacetamide, N-methylpyrrolidine, dimethyl There are compounds such as sulfoxide and tetramethylene sulfone, which are advantageous in terms of compatibility with the polymer and radioactive solvent recovery when dimethylacetamide or dimethylformamide is used. The amount of solvent used should be adjusted to 15 ~ 40% of the solid content of the polymer, and less than 15% or more than 40% adversely affects radioactivity.

Compounds for improving oxygen and antioxidant properties in the air include bisphenol, monophenol, phenol, polymer phenol resin, amine resin, sulfur resin and phosphorus resin. 2,2-methylenebis (4-methyl-6-t-butylphenol), 2,6-di-t-butyl paracresol, 2,6-di-t-butyl-4-ethyl phenol, 1,3, 5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, dilaurylthiodipropionate, triphenyl, triphenyl phosphite, diphenylisodecyl phos The most advantageous compound is dilauryl chiodipropion, which is a phosphite, tris (northphenyl) phosphite, which does not deteriorate the inherent physical properties of the elastomer and does not adversely affect radioactivity but improves the antioxidant properties by oxygen in the atmosphere. It is an acid type compound. Suitable amount of dilauryl thiodipropionate compound is 0.05 to 4% by weight relative to the polymer solid content, the antioxidant is insufficient at less than 0.05% by weight, the antioxidant is more than a certain effect when used more than 4% by weight Not elevated, not only uneconomical, but also inhibit the inherent properties of the elastomer and adversely affect radioactivity.

The polymer solution prepared by the above method was prepared using a conventional dry spinning method to prepare a polyurethane elastic yarn of 70 denier after spinning and measured various physical properties.

The following Examples and Comparative Examples illustrate the present invention more specifically, but do not limit the present invention. In addition, the tensile intermittence, elongation and inertia recovery rate shown in the examples were evaluated according to KSK 0219, and the oxidation resistance was evaluated by physicalization after being left in the air for a certain time, and the heat resistance was maintained after treating the elastic yarn for 60 minutes in a hot air dryer at 130 ° C. And color change (Gray Scale: water supply determination using ISO international standard).

Example 1

1 mol of polyhexamethylene carbonatediol having a molecular weight of 2,000 synthesized by condensation reaction of 1,4-butanediol with diphenyl carbonate, 1 mol of polytetramethylene glycol having a molecular weight of 1,800, and 0.3 mol of N-isopropyl diethanolamine at 82 ° C. After stirring under reduced pressure to remove water, 4.5 mol of 4,4'-diphenylmethane diisocyanate preheated at 50 ° C. was added thereto, followed by polymerization at 80 ° C. for 60 minutes under a nitrogen gas atmosphere to prepare a prepolymer. The prepolymer was dissolved in dimethyl acetamide to cool the solution to 5 ° C., followed by 1 mol of ethylenediamine, linear amine, 0.9 mol of 1,2-propylene diamine, and 0.1 mol of methacrylate diamine, as chain growth agents. And a chain growth agent solution in which 0.1 mol of 1,4-cyclohexane diamine was dissolved in dimethyl acetamide at a concentration of 15% was gradually added to the prepolymer to obtain a polymer having a viscosity of 3,000 poises.

A solution obtained by dissolving 0.2 mol of isopropyl amine in 15% concentration in dimethyl acetamide was slowly added to the polymer to obtain a polymer having a viscosity of 3,000 poises. After the completion of the polymerization, the anti-oxidant dilaufilthio dipropionate-based compound was dissolved in 10% concentration in dimethylacetamide so that the final polymer solid content was 0.3% by weight, and the solid content of the final polymer was adjusted to 30%. The viscosity at this time is 2700 poise (45 degreeC). This polymer was prepared by spinning a conventional 70-denier polyurethane elastic yarn using a dry spinning method and the physical properties were evaluated and the results are shown in Table 1.

Comparative Example 1

0.2 mole of polyhexamethylene carbonate diol having a molecular weight of 2,000 and 1.8 mole of polytetramethylene glycol having a molecular weight of 1,800 were used in the same manner as in Example 1, and the results of the evaluation of the physical properties are shown in Table 1.

Comparative Example 2

Polymerization was carried out in the same manner as in Example 1 except that N-isopropyl diethanolamine having a tertiary amino group was not used. The results of the evaluation of the physical properties are shown in Table 1.

Comparative Example 3

Polymerization was carried out in the same manner as in Example 1, except that the dilaurylthio dipropionate-based compound for improving antioxidant properties was not used.

Claims (5)

One long-chain diol (A) and a tertiary amino group obtained by mixing a polyether diol (A-1) having a number average molecular weight of 1,000 to 28,00 with a polycarbonate diol (A-2) having a number average molecular weight of 500 to 2500 The polyol (B) having 1 to 7 amino groups and 3 to 12 carbon atoms is prepolymerized with an excess of an organic diisocyanate compound (C), mixed with a solvent at a predetermined ratio, and then a diamine compound (D) as a chain growth agent is added. After the polymerization is completed by using 0.60 to 0.98 moles of the prepolymer and adding the chain terminator monoamine (E) to 1 to 30 mole% of the total amine usage, the antioxidant (F) is 0.05 to 4 wt% based on the polymer solids. Method for producing a polyurethane-based elastic fiber, characterized in that the addition to. The primary amines according to claim 1, wherein the polyol (B) is represented by R-NH ₂ (where R = C _n H _{2n + 1} , n = 1-30), and ethylene oxide, propylene oxide or butylene oxide. Method for producing a polyurethane-based elastic fiber, characterized in that the diols and derivatives thereof made by adding 2 to 60 moles and the like. The molar ratio of polyether diol (A-1) to polycarbonate diol (A-2) in the long chain diol (A): (A-1) / (A-2) is 0.3 to 10. Method for producing a polyurethane-based elastic fiber characterized in that. The method for producing a polyurethane-based elastic fiber according to claim 1, wherein the molar ratio of the long-chain diol (A) and the polyol (B) is 5 to 45 (A / B). The polyurethane-based elastic fiber according to claim 1, wherein the diisocyanate compound (C) is used in a molar ratio of C / (A + B) = 1.23 to 2.5 with respect to the long chain diol (A) and the polyol (B). Manufacturing method.