JPH10195171A - Production of electron-beam-curing thermoplastic polyurethane resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a thermoplastic polyurethane resin which can give a molding having excellent properties when cured by irradiation with electron beams. SOLUTION: In a thermoplastic polyurethane resin comprising a polyol, a chain extender and a polyisocyanate, 10-100mol%, based on the chain extender, mixture comprising an unsaturated alcohol and an unsaturated glycol in a 1:10 to 10:1 molar ratio is added and reacted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a thermoplastic polyurethane resin curable by an electron beam or radiation.

[0002]

2. Description of the Related Art Conventionally, when electron beam curing is performed using a thermoplastic polyurethane resin (hereinafter abbreviated as TPU), for example, as disclosed in JP-A-59-135250, trimethylolpropane trimeta is added to a general TPU. There has been known a method of kneading a polyfunctional unsaturated group-containing crosslinking agent such as acrylate, and irradiating with an electron beam or radiation after molding.

[0003]

However, in the conventional method of kneading a polyfunctional unsaturated group-containing crosslinking agent to obtain a TPU, only the crosslinking agent is crosslinked by electron beam curing, and the TPU is not crosslinked. For this reason, there is a problem that a TPU molded product obtained by electron beam curing cannot obtain sufficient performance such as heat resistance, solvent resistance, and mechanical properties. An object of the present invention is to provide a method for producing a TPU capable of obtaining an electron beam-cured molded product having excellent physical properties, compared to a conventional electron beam-cured TPU molded product having only insufficient physical properties. And

[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 has been found that a molded article having excellent physical properties can be obtained by adding and reacting a mixture of an unsaturated monoalcohol and an unsaturated glycol, thereby completing the present invention. That is, according to the present invention, in the thermoplastic polyurethane resin comprising a polyol, a chain extender and a polyisocyanate, a part of the chain extender,
1 to 10 to 10 of unsaturated alcohol and unsaturated glycol
The mixture consisting of a molar ratio of 1 to 1
A method for producing an electron beam-curable thermoplastic polyurethane resin, characterized by adding 100 mol% and reacting, is provided.

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 polyvalent carboxylic acid include succinic acid, adipic acid, sebacic acid, hydrogenated dimer acid, phthalic acid, phthalic acid alkyl esters, and trimet 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 extender used in the present invention includes 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 unsaturated monoalcohol used in the present invention is 2-hydroxyethyl acrylate (HE
A), 2-hydroxymethacrylate (HEMA),
Examples thereof include 2-hydroxypropyl methacrylate, trimethylolpropane dimethacrylate, trimethylolpropane diacrylate, 2-hydroxyethyl monomaleate, 2-hydroxyethyl itaconate, and allyl alcohol. These can be used alone or as a mixture of two or more.

The unsaturated glycol used in the present invention includes trimethylolpropane monomethacrylate,
Trimethylolpropane monoacrylate, bis (2-hydroxyethyl ester) maleate (BHEM),
Bis (2-hydroxyethyl ester) fumarate, bis (3-hydroxypropyl ester) maleate, bis (3-hydroxypropyl ester) fumarate, bis (4-hydroxybutyl ester) maleate (BH
BM), bis (4-hydroxybutyl ester) fumarate, 2,3-dihydroxypropyl acrylate,
2,3-dihydroxypropyl methacrylate and the like. These can be used alone or as a mixture of two or more.

The mixture ratio of the unsaturated monoalcohol and the unsaturated glycol is preferably 1:10 to 10: 1 in molar ratio. Particularly, 8 to 2 to 5 to 5 is preferable. If the mixture ratio of unsaturated monoalcohol to unsaturated glycol is less than 1 to 10, TP
The melt viscosity of U rises, deteriorating the moldability and losing the elasticity of the electron beam cured product. And if it exceeds 10: 1,
It is not preferable because the molecular weight of TPU decreases.

The amount of the mixture of the unsaturated monoalcohol and the unsaturated glycol is preferably 10 to 100 mol% based on the chain extender. Particularly, 20 to 50 mol% is preferable. When the amount is less than 10 mol%, remarkable improvement in properties due to electron beam curing is not observed.

The electron beam-curable TPU of the present invention comprises a polyisocyanate, a polyol, a chain extender and a mixture of an unsaturated monoalcohol and an unsaturated glycol. It is manufactured by blending such that the ratio (R value) becomes 0.7 to 1.3, preferably 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 ratio of the number of moles of the active hydrogen group of the chain extender to the number of moles of the active hydrogen group of the polyol (R ′ value)
Is adjusted to be 0.1 to 10. When R ′ is less than 0.1, TPU is not preferable because it becomes sticky and becomes difficult to handle. If it exceeds 10, the TPU becomes brittle, which is not preferable.

The method for producing an electron beam-curable TPU of the present invention is a known method for producing a TPU, such as a one-shot method, a prepolymer method, a batch reaction method, a continuous reaction method, a method using a kneader, a method using an extruder, and the like. The following method can be adopted. For example, in a method using a kneader, a polyol, a chain extender, an unsaturated monoalcohol and an unsaturated glycol are charged into a kneader, heated to 80 ° C., charged with a polyisocyanate, reacted for 10 to 60 minutes, and cooled. Powder or block TPUs can be produced. These powdery or blocky resins are
If necessary, it is formed into pellets by an extruder or the like. 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.

In producing the electron beam-curable TPU of the present invention, a catalyst can be added as required. Catalysts that can be used include, for example, triethylamine, triethylenediamine, N-methylimidazole, N-ethylmorpholine, 1,8-diazabicyclo, 5,4,0 undecene-
7 (DBU); organic metals such as potassium acetate, stannas octoate and dibutyltin dilaurate; and phosphorus-based compounds such as tributylphosphine, phosphorene and phosphorene oxide. When producing the electron beam-curable TPU of the present invention, a polymerization inhibitor can be added as necessary. Polymerization inhibitors that can be used are, for example, p-benzoquinone, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol.

To the electron beam-curable TPU of the present invention, if necessary, a polyfunctional unsaturated group-containing crosslinking agent such as ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, or triacrylisocyanurate is added. be able to. The addition amount is preferably 1 to 10% by weight based on TPU. These crosslinkers are TP
It can be added during the production of U or after the production of the TPU. Electron beam curable TPU obtained by the present invention
, Another resin can be added as needed. Resin that can be used is, for example, ABS resin, SAN resin, vinyl chloride resin, polypropylene, polystyrene, polyacetal, polyamide, polyester, polyester ether, polycarbonate, epoxy resin, mesh resin, phenol resin, silicone resin, fluorine resin, and the like. .
These resins are the electron beam curable TPU100 of the present invention.
It can be added in an amount of 1 to 50 parts by weight based on parts by weight.

The electron beam-curable TPU obtained according to the present invention may contain other substances as necessary. 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, A hydrolysis inhibitor, a reaction retarder and the like.

The electron beam-curable 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.

After molding, the TPU of the present invention can be cured by irradiating the molded article with an electron beam or γ-ray by an electron beam or γ-ray irradiation device. Applicable devices are, for example, an electron beam irradiation device TYPE: CB manufactured by Iwasaki Electric Co., Ltd.
It is 250/15 / 180L. Irradiation condition is 3-50M
rad is preferred. Heat treatment can be performed before or after irradiation as necessary. Electron beam curable TP of the present invention
U can be cured by irradiation with ultraviolet light (UV) by adding a photopolymerization initiator such as benzoin ethyl ether or azobisisobutyronitrile. Printing ink,
When used as a UV cure type in applications such as coatings and adhesives for optical fibers and the like, the electron beam-curable TPU of the present invention can be used by dissolving it in a solvent, reactive diluent, or the like.

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".

Example 1 In a reaction vessel equipped with a stirrer, 100 parts of an ether-based polyol (PTG1000 manufactured by Hodogaya Chemical Co., Ltd., hydroxyl value 112 mgKOH / g) as a polyol, and 1,1 as a chain extender
4.4 parts of a mixture of 9 parts of 4-butanediol (BG) and a mixture of 2-hydroxyacrylate (HEA, molecular weight 116) and bis (2-hydroxyethyl ester) maleate (BHEM, molecular weight 204) at a molar ratio of 7: 3 ( The amount of the mixture with respect to BG was 31 mol%), and the mixture was uniformly mixed.
After the temperature was adjusted to 0 ° C., 55 parts of 4,4′-diphenylmethane diisocyanate (R value: 1.00) was added to carry out a urethanization reaction. When the reactant reached 90 ° C., it was poured into a vat and solidified on the vat. The obtained solidified product was aged in an electric furnace at 80 ° C. for 24 hours, and then the solidified product was pulverized to obtain a flake-shaped electron beam-curable TPU (unsaturated group-containing TPU) 16
8 parts were obtained. The obtained unsaturated group-containing TPU is molded by using a hot press at a molding temperature of 190 to 200 ° C. and a molding pressure of 100 kgf.
/ Cm ² to form a sheet having a thickness of 0.4 to 0.5 mm. Irradiate both sides of this sheet with electron beams, and
After standing for a time, the tensile test, dynamic viscoelasticity, and gel fraction were measured. Table 1 shows the results. [Electron Beam Irradiation Method] TYPE: CB250 / 15/18 manufactured by Iwasaki Electric Co., Ltd.
0L, an acceleration voltage of 250 kV, an unsaturated group-containing TP
Irradiate 20 Mrad of electron beam to both sides of the U sheet. [Tensile test method] Based on JIS-K7311, JIS
No. 3 dumbbell, pulling speed 500 mm / min. Do with. [Dynamic Viscoelasticity Measurement Method] Dynamic Viscoelasticity Tester: Leo Vibron DDV-III-E
test frequency 11 (using Orientec)
The dynamic storage modulus (E ′) is measured at a test frequency range of −150 ° C. to + 200 ° C. in Hz. E 'at 25 ° C is 10
Assuming 0, the retention of E ′ at 100 ° C., 125 ° C., and 150 ° C. is determined. [Measurement method of gel fraction] The gel fraction was determined by immersing the sheet in dimethylformamide (DMF) at 25 ° C. for 72 hours, and then evaporating the solvent.
Find the fraction.

Example 2 100 parts of the unsaturated group-containing TPU obtained in Example 1 and 10 parts of ethylene glycol dimethacrylate (EDMA) were mixed with a Labo Plastomill mixer (Toyo Seiki 20C200).
-C60), and kneaded at 150 to 170 ° C for 30 minutes to obtain 110 parts of an unsaturated group-containing TPU composite. The obtained unsaturated group-containing TPU composite was treated and tested in the same manner as in Example 1. Table 1 shows the results.

Example 3 In Example 1, the molar ratio between HEA and BHEM was 5: 5.
(The amount of the mixture based on BG was 37 mol%). As a specific compounding amount, PTG1000 is set to 100
Parts, 9 parts of BG, 4.2 parts of a mixture of HEA and BHEM at a molar ratio of 5: 5, and 55 parts of MDI (R value: 1.00).
Thus, 168 parts of an unsaturated group-containing TPU was obtained. 100 parts of this unsaturated group-containing TPU and 3 parts of EDMA were charged into a Labo Plastomill mixer, treated in the same manner as in Example 2, and tested. Table 1 shows the results.

Comparative Example 1 In Example 1, polymerization was performed using only PTG1000, BG, and MDI so that the R value was 1.00 and R ′ was 1.09. Other than that, the treatment and test were performed in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 2 100 parts of the TPU obtained in Comparative Example 1 and 10 parts of EDMA were put into a Labo Plastomill mixer, processed in the same manner as in Example 2, and tested. Table 1 shows the results.

Example 4 In Example 1, a caprolactone-based polyol (PL210 manufactured by Daicel Chemical Co., Ltd.
KOH / g) was carried out using bis (4-hydroxybutyl ester) maleate (BHBM, molecular weight 260) in unsaturated glycol. The specific composition is PL
100 parts of 210, 9 parts of BG, 4.8 parts of a mixture of HEA and BHBM at a molar ratio of 8 to 2 (the amount of the mixture with respect to BG is 33 mol%), and 55 parts of MDI (R value: 1.00). Thus, 168 parts of an unsaturated group-containing TPU was obtained. This TPU containing an unsaturated group was treated and tested in the same manner as in Example 1. Table 2 shows the results.

Example 5 Example 4 In the same manner, the molar ratio between HEA and BHBM is 8: 2.
Was carried out in an amount of 6.7 parts (the amount of the mixture relative to BG was 47 mol%). The specific formulation is PL2
10, 100 parts of BG, 9 parts of BG, 6.7 parts of a mixture of HEA and BHBM at a molar ratio of 8: 2, 57 parts of MDI (R value: 1.0
0). Thus, the unsaturated group-containing TPU172
Got a part. To 100 parts of the unsaturated group-containing TPU, 3 parts of trimethylolpropane trimethacrylate (TMPMMA) was added, and the mixture was treated in the same manner as in Example 2 and tested. Table 2 shows the results.

Comparative Example 3 In the same manner as in Example 4, a TPU was obtained by adjusting only the PL210, BG and MDI so that the R value was 1.00 and R ′ was 1.08. 100 parts of this TPU, TMPMA3
The part was put into a Labo Plastomill mixer, treated and tested in the same manner as in Example 2. Table 2 shows the results.

[0027]

The TPU obtained by the method of the present invention
By irradiating with an electron beam, excellent tensile strength, excellent elastic modulus retention at high temperatures and excellent gel fraction characteristics can be obtained. Further, various properties such as compression set, permanent elongation, heat resistance, water resistance, chemical resistance, oil resistance, and abrasion resistance are 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 automobile parts, various gears, seals and packings, connectors, rubber 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,
It can be effectively used for grips, snow chains, etc., as well as adhesives, paints, etc. by dissolving in a solvent.

Claims (1)

[Claims] 1. A thermoplastic polyurethane resin comprising a polyol, a chain extender and a polyisocyanate, wherein a part of the chain extender comprises a mixture of unsaturated alcohol and unsaturated glycol in a molar ratio of 1:10 to 10: 1. A method for producing an electron beam-curable thermoplastic polyurethane resin, wherein 10 to 100 mol% is added to a chain extender and reacted.