JPH1129619A - Production of thermoplastic polyurethane resin excellent in mechanical property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin having stable, excellent mechanical properties, and useful for high-pressure hoses, medical tubes, films, etc., by reaction between a polyol, chain extender, amidodiol, and polyisocyanate. SOLUTION: This thermoplastic polyurethane resin in powdery or lumpy form is obtained by reaction between a polyol (e.g. tetrahydrofuran, propylene oxide), a chain extender (e.g. ethylene glycol, diethylene glycol), 0.5-50 (pref. 1-30) mol, based on the chain extender, of an amidodiol intramolecularly bearing one amido group of the formula (R1 is a 2-10C hydrocarbon; R2 is a 1-10C hydrocarbon) as part of the chain extender, and a polyisocyanate (e.g. phenylene diisocyanate, tolylene diisocyanate), in the presence of, as necessary, a catalyst (e.g. triethylamine, triethylenediamine) at 80 deg.C for 10-60 min through process using e.g. a kneader, and then by cooling the reaction product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a thermoplastic polyurethane resin having excellent mechanical properties.

[0002]

2. Description of the Related Art Heretofore, as a most common method for improving the mechanical properties of a thermoplastic polyurethane resin (hereinafter abbreviated as TPU), there is known a method in which a polyisocyanate is excessively added during the production of a TPU. Was. This means that a small amount of isocyanate (NCO) group is contained in the polyurethane chain and a crosslinking reaction such as an allophanate bond is caused by heating, or a urea bond or a buret bond is caused by reacting with moisture in the air. Has improved mechanical properties.

[0003]

However, the conventional method of excessively blending NCO cannot produce stable products such as variations in mechanical properties and variations in the melt viscosity of TPU. There was a problem. This is presumed to be because the reaction between the NCO group and water such as in air is greatly affected by various conditions, and the resulting chemical bonds or products are diversified. The present invention is an improvement over the conventional method of manufacturing a TPU having many variations, and has a TP having stable and excellent mechanical properties.
It is intended to provide a method for producing U.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve such a conventional problem, and as a result, have found that TP
In producing U, it was found that a molded article having excellent mechanical properties could be obtained by adding and reacting an amide diol having one amide group in the molecule, and completed the present invention. . That is, according to the present invention, in a TPU comprising a polyol, a chain extender and a polyisocyanate, a part of the chain extender has a general formula [I]
Wherein the amide diol having one amide group in the molecule is added to the chain extender in an amount of 0.5 to 50 mol% and reacted to obtain a thermoplastic polyurethane resin having excellent mechanical properties. A manufacturing method is provided.

Embedded image (However, R ₁ represents a hydrocarbon group having 2 to 10 carbon atoms, and R ₂ represents a hydrocarbon group having 1 to 10 carbon atoms.)

The polyol used in the present invention includes:
Examples thereof include polyethers, polyesters, polyesteramides, polyetheresters, and polycarbonates having a hydroxyl group at the terminal and having a molecular weight of 400 to 10,000 which are usually used as a reaction partner of polyisocyanate. Examples of the polyethers include a polymerization product of tetrahydrofuran, propylene oxide and ethylene oxide, a copolymerization product thereof, and a graft polymer of a polyether with a vinyl monomer. Examples of the polyesters and polyesteramides include those obtained by a condensation reaction from a polyhydric alcohol and a polycarboxylic acid, optionally using a diamine or an amino alcohol in combination. As polyhydric alcohols, for example, ethylene glycol, diethylene glycol, butylene glycol,
Examples include hexamethylene glycol, 2-methylpropanediol, neopentyl glycol, 3-methylpentanediol, 2-methyloctanediol, 1,9 nonanediol, cyclohexanedimethanol, glycerin, trimethylolpropane, and the like. Examples of the polycarboxylic acids include succinic acid, adipic acid, sebacic acid, dimer acid, hydrogenated dimer acid, phthalic acid, alkyl phthalates, trimet acid, maleic acid, fumaric acid,
And itaconic acid. Further, those obtained by ring-opening polymerization of cyclic esters such as butyrolactone, valerolactone, and caprolactone are also included. Examples of the polyetheresters include those obtained in the same manner as polyesters except that polyethers are used for part or all of the polyhydric alcohols used in the condensation reaction for obtaining the polyesters. Examples of the polycarbonates include those obtained by a transesterification reaction between a diol such as 1,6 hexanediol and 1,4 cyclohexanedimethanol and a cyclic carbonate such as dialkyl carbonate, diaryl carbonate or ethylene carbonate.

The chain extenders used in the present invention include ethylene glycol, diethylene glycol, propylene glycol, 1,4 butanediol, 1,6 hexanediol, 1,9 nonanediol, bis-βhydroxyethoxybenzene, 3-methyl -1,5 pentanediol, neopentyl glycol, N-phenyldiisopropanolamine, monoethanolamine and the like.

Examples of the polyisocyanate used in the present invention include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, naphthylene diisocyanate, diphenylmethane diisocyanate, and aromatic diisocyanates comprising isomers thereof. 6
Aliphatic diisocyanates such as hexamethylene diisocyanate, 1,12-dodecane diisocyanate, trimethyl-hexamethylene diisocyanate, cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, alicyclic diisocyanates such as norbornane diisocyanate methyl, etc. Can be mentioned. Further, an isocyanate group-terminated compound obtained by the reaction of these compounds with an active hydrogen group-containing compound, or a modified polyisocyanate obtained by the reaction of these compounds, for example, a carbodiimidization reaction, etc., can also be mentioned. Also, methanol, n-butanol,
Examples thereof include polyisocyanates in which one part is stabilized with a blocking agent having one active hydrogen in a molecule such as benzyl alcohol, ethyl acetoacetate, ε-caprolactam, methyl ethyl ketone oxime, phenol, and cresol.

The amide diol used in the present invention is a diol having one amide group in the molecule and is represented by the general formula [I]. The amide diol of the present invention is obtained, for example, by reacting a monoalkanolamine with an oxyacid and / or a cyclic ester.

Embedded image (However, R ₁ represents a hydrocarbon group having 2 to 10 carbon atoms, and R ₂ represents a hydrocarbon group having 1 to 10 carbon atoms.) As the monoalkanolamine, a hydrocarbon group (R ₁ ) having 2 to 10 carbon atoms is preferable. For example, monoethanolamine, monopropanolamine, monobutanolamine, monohexanolamine and the like can be mentioned. As the oxyacid, those having 1 to 10 carbon atoms in the hydrocarbon group (R ₂ ) are preferable. And aromatic oxyacids and alicyclic oxyacids. Examples of the cyclic ester include intramolecular esters such as γ-butyrolactone, δ-valerolactone, β-methyl-δ-valerolactone, and ε-caprolactone. The amide diol of the present invention can also be obtained by reacting a monoalkanolamine with an oxyacid chloride such as oxypropionic chloride. The amide diol of the present invention can be obtained by a condensation reaction or ring-opening reaction between a monoalkanolamine and an oxyacid under ordinary reaction conditions.

The amount of the amide diol represented by the general formula [I] is preferably 0.5 to 50 mol% based on the total amount of the chain extender. Particularly, 1 to 30 mol% is preferable. If it is less than 0.5 mol%, no remarkable improvement in mechanical properties is observed,
If it exceeds 0 mol%, the melt viscosity of the obtained TPU increases, and the moldability decreases, which is not preferable.

The TPU of the present invention comprises a polyisocyanate polyol, a chain extender and an amide diol having a ratio (R value) of the number of moles of isocyanate groups of the polyisocyanate to the total number of moles of active hydrogen groups of 0.7 to 1.3; Preferably, it is manufactured by compounding so as to be 0.9 to 1.05. When the isocyanate group is excessively mixed, the isocyanate group is prevented from remaining by heat treatment or the like after the TPU is manufactured. The chain extender, amide diol and polyol have a ratio (R 'value) of the total number of moles of active hydrogen groups of the chain extender and amide diol to the moles of active hydrogen groups of the polyol of 0.1.
It is blended so as to be ~ 15. If R ′ is less than 0.1, the TPU becomes sticky and becomes difficult to handle, which is not preferable. If it exceeds 15, the TPU becomes brittle, which is not preferable.

[0011] The method for producing a TPU of the present invention uses a known TP.
U production method, for example, a one-shot method, a prepolymer method, a patch reaction method, a continuous reaction method, a method using a kneader,
A method such as a method using an extruder can be employed. For example,
In the method using a kneader, a polyol, a chain extender, and an amide diol are charged into a kneader, heated to 80 ° C., charged with a polyisocyanate, reacted for 10 to 60 minutes, and cooled to obtain a powdery or block-like TPU. Can be manufactured. These powder or block resins are formed into pellets by an extruder or the like, if necessary. As a device used for the production, a kneader connected with a multi-component measuring mixer or the like, a single-screw or multi-screw extruder, or the like can be used.

When producing the TPU of the present invention, a catalyst can be added as required. Catalysts which can be used include, for example, amines such as triethylamine, triethylenediamine, N-methylimidazole, N-ethylmorpholine, 1,8-diazabicyclo, 5,4,0undecene-7 (DBU), potassium acetate, stannasoctoate. And organic compounds such as dibutyltin dilaurate, and phosphorus compounds such as tributylphosphine, phosphorene and phosphorene oxide.

The TPU obtained according to the present invention may contain other resins as required. Resin that can be used, for example, ABS resin, SAN resin, vinyl chloride resin, polypropylene, polystyrene, polyacetal,
Examples include polyamide, polyester, polyester ether, polycarbonate, epoxy resin, amino resin, phenol resin, silicone resin, and fluororesin. These resins can be added in an amount of 1 to 50 parts by weight based on 100 parts by weight of the TPU of the present invention.

The TPU obtained according to the present invention may contain other substances as required. Substances that can be added include, for example, antioxidants, ultraviolet absorbers, heat resistance improvers,
Plasticizers, lubricants, antistatic agents, conductivity-imparting agents, coloring agents, inorganic and organic fillers, fibrous reinforcing materials, matting agents, hydrolysis inhibitors, reaction retarders and the like.

The TPU of the present invention can be applied to all commonly used molding methods and molding conditions for thermoplastic polyurethane resins. For example, it is molded by a molding method such as extrusion molding, injection molding, blow molding, calendar processing, roll processing, press processing, centrifugal molding, and rotational molding.

[0016]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In Examples and Comparative Examples,
All "parts" mean "parts by weight".

Synthesis Example 1 A 500 ml four-necked flask was equipped with a stirrer, a thermometer, a cooler and a separating funnel. 100 parts of monoethanolamine (special grade reagent) was charged into the flask, and ε-caprolactone (reagent) was stirred. 196 parts are added in several portions. Thereafter, the temperature was raised to 120 ° C., and the reaction was maintained for 16 hours while maintaining the temperature. Fourier transform infrared spectrophotometer (FT-IR)
The end point of the reaction was confirmed from the change in the absorption peak of the amide bond. The reaction was cooled to room temperature to obtain an amide group-containing diol.

Synthesis Example 2 An amide group-containing diol was obtained in the same manner as in Synthesis Example 1 except that δ-valerolactone (special grade reagent) was used instead of ε-caprolactone. The specific compounding amount is 100 parts of monoethanolamine and 172 parts of δ-palerolactone.

Example 1 In a reaction vessel equipped with a stirrer, an ether-based polyol (PTG1000 manufactured by Hodogaya Chemical, hydroxyl number 1) was used as a polyol.
12 mgKOH / g) 100 parts, 1,4 as a chain extender
8.9 parts of butanediol (1,4BG) and 0.18 part of the amide diol (2 carbon atoms of R ₁ and 5 carbon atoms of R ₂ ) synthesized in Synthesis Example 1 (1 mol based on the total amount of the chain extender) %), Mix evenly, adjust to 100 ° C,
50 parts of 4'-diphenylmethane diisocyanate (MDI) was added, and a urethanization reaction was carried out (R value and R 'value at this time were 1.00). When the reactant reached 90 ° C., it was poured into a vat and solidified on the vat. The obtained solid was aged in an electric furnace at 80 ° C. for 24 hours, and after confirming that the remaining isocyanate (residual NCO) of the solid was consumed, the solid was pulverized, and the TPU 15 of the present invention was pulverized.
9 parts were obtained. The obtained TPU is formed into a 110 × 55 × 2 mm sheet under the conditions of a molding temperature of 160 to 190 ° C. and a molding pressure of 600 kgf / cm ² using an injection molding machine. After annealing this sheet at 100 ° C. for 16 hours, a tensile test was performed. Table 1 shows the results. [Tensile test method] Based on JIS-K7311,
No. 3 dumbbell, pulling speed 500 mm / min. Do with. [Method for measuring residual NCO] From the absorbance spectrum of FT-IR (Fourier transform infrared spectrophotometer), the absorbance at an NCO-based absorption wave number of 2270 cm ^-1 and the phenyl-based absorption wave number of 16
It is determined from the absorbance ratio of the absorbance of 00 cm ^-1 .

Example 2 Example 1 was repeated except that amide diol was added in an amount of 10 mol% based on the total amount of the chain extender.
Was performed in the same manner as described above. The R value at this time is 1.00,
The R 'value is 1.05. The specific compounding amount is P
100 parts of TG1000, 8.1 parts of 1,4BG, 1.8 parts of amide diol, and 52 parts of MDI. Thus, 161 parts of the TPU of the present invention were obtained. The obtained TPU was treated and tested in the same manner as in Example 1. Table 1 shows the results.

Example 3 Example 1 was repeated except that amide diol was added in an amount of 20 mol% based on the total amount of the chain extender.
Was performed in the same manner as described above. The R value at this time is 1.00,
The R 'value is 1.10. The specific compounding amount is P
100 parts of TG1000, 7.2 parts of 1,4BG, 3.5 parts of amide diol, and 53 parts of MDI. Thus, 163 parts of the TPU of the present invention were obtained. The obtained TPU was treated and tested in the same manner as in Example 1. Table 1 shows the results.

Example 4 Example 1 was repeated except that the amide diol was added in an amount of 35 mol% based on the total amount of the chain extender.
Was performed in the same manner as described above. The R value at this time is 1.00,
The R 'value is 1.18. The specific compounding amount is P
100 parts of TG1000, 5.9 parts of 1,4BG, 6.1 parts of amide diol, and 55 parts of MDI. Thus, 166 parts of the TPU of the present invention were obtained. The obtained TPU was treated and tested in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 1 In Example 1, PTG1000, 1,4BG, MD
The same procedure as in Example 1 was carried out except that the R value was 1.07 and R 'was 1.00 with only I. Under the same heat treatment conditions as in Example 1 for the solidified product, the remaining NCO was not completely consumed, and was left at room temperature for about 10 days until it was completely consumed. The TPU thus obtained was treated and tested in the same manner as in Example 1. Table 1 shows the results.

Example 5 In Example 1, a caprolactone-based polyol (PL220 manufactured by Daicel Chemical Co., Ltd.
OH / g) so that the amide diol (carbon number of R ₁ and carbon number of R ₂ ) obtained in Synthesis Example 2 was 10 mol% with respect to the total amount of the chain extender. The procedure was performed in the same manner as in Example 1 except for the mixing. At this time, the R value is 1.00 and the R ′ value is 3.15. As a specific compounding amount, 100 parts of PL220, 1,4BG1
2.2 parts, 2.4 parts of amide diol and 52 parts of MDI. Thus, 166 parts of the TPU of the present invention were obtained.
The obtained TPU was treated and tested in the same manner as in Example 1. Table 2 shows the results.

COMPARATIVE EXAMPLE 2 The same procedure as in Example 5 was carried out except that PL220, 1, 4BG, and MDI were used so that the R value was 1.07 and R ′ was 3.0. did. Under the same heat treatment conditions for the solidified product as in Example 5, the remaining NCO was not completely consumed, and was left at room temperature for about 10 days until it was completely consumed. The TPU thus obtained was treated and tested in the same manner as in Example 1. Table 2 shows the results.

[0026]

The TPU obtained by the method of the present invention
Has excellent mechanical strength. Further compression set,
Various properties such as permanent elongation, heat resistance, hot water resistance, chemical resistance, oil resistance, and abrasion resistance are also improved.

The TPU of the present invention includes various hoses and tubes such as high-pressure hoses, medical tubes, oil / pneumatic tubes, fuel tubes, coating hoses, fire hoses, conveyor belts, air mats, diaphragms, and keyboards. Various films such as seats, synthetic leather, life jackets, wet suits, hot melt films,
Power and communication cables, computer wiring, automotive wiring,
Various electric wires and cables such as curl cords, various ropes, various drive belts, various types of extruded molded products such as slip stoppers, and for injection molding, ball joints, dust covers, pedal stoppers, door lock strikers, bushes, springs Covers, bearings, anti-vibration parts,
Such as automotive parts, various gears, seals and packings, connectors, wrapper screens, mechanical parts such as printing drums, soles and points for sports shoes, shoe-related parts such as women's shoes top lifts, rollers, casters,
Gribbs, snow chains, etc., and can also be effectively used for adhesives, paints, etc. by dissolving in solvents.

Claims (1)

[Claims] 1. A thermoplastic polyurethane resin comprising a polyol, a chain extender and a polyisocyanate, wherein a part of the chain extender is an amide diol having one amide group in a molecule represented by the general formula [I]: Characterized in that 0.5 to 50 mol% is added to the chain extender and reacted.
A method for producing a thermoplastic polyurethane resin having excellent mechanical properties. Embedded image (However, R ₁ represents a hydrocarbon group having 2 to 10 carbon atoms, and R ₂ represents a hydrocarbon group having 1 to 10 carbon atoms.)