JPH1129701A - Flame retardant thermoplastic polyurethane resin composition and molding material thereof - Google Patents

Abstract

(57) [Summary] PROBLEM TO BE SOLVED: To provide a mold, a tensile property, a heat aging resistance,
Non-C type with excellent heat and moisture resistance, excellent appearance and excellent flame retardancy
A flame-retardant thermoplastic polyurethane resin molding material
Therefore, cables for automobiles, communication cables,
Cables, mining cables, automotive interior materials, various vehicle interiors
It can be widely applied to materials and interior materials of houses. The present invention relates to a thermoplastic polyurethane resin.
(A) Non-halogen flame retardant (B)
Non-halo in the thermoplastic thermoplastic polyurethane resin composition
Gen-based flame retardant (B) is an alkyl substituted aromatic phosphate
Ter is a flame-retardant thermoplastic polyurethane resin composition
Shear rate at 200 ° C. 10 to 10^Threesec ^-1Melt viscosity at
Degree 10^Three-10^FiveFlame retardant characterized by poise
Thermoplastic polyurethane resin composition and molding using the same
material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-halogen flame-retardant polyurethane resin composition comprising a thermoplastic polyurethane resin and a non-halogen flame retardant, and more particularly, to extrusion molding, injection molding, blow molding, calendering. Non-halogen flame-retardant products formed by molding, such as automotive cables, communication cables, vehicle cables, mining cables, automotive interior materials, various vehicle interior materials, house interior materials, etc. , Is preferably used for applications that dislike the generation of halogen gas due to fire, by using a specific flame retardant, by making the composition a specific melt viscosity,
The present invention relates to a non-halogen flame-retardant thermoplastic polyurethane resin composition having excellent moldability, tensile properties, heat aging resistance, heat and humidity resistance, appearance, and flame retardancy, and a molding material using the same.

[0002]

2. Description of the Related Art Thermoplastic polyurethane resin (hereinafter TP)
(Abbreviated as U) is excellent in flexibility, tensile properties, low temperature properties, oil resistance, flex fatigue resistance, abrasion resistance, etc., and is used as a thermoplastic elastomer for sports shoe soles, ski boots, various hoses, tubes, films, etc. Widely used. However, TPU is easily flammable, and various flame retardants are added and blended to products requiring flame retardancy to impart flame retardancy. Among them, halogen-containing flame retardants are TPU
Has been commonly used for flame retardancy.

However, the use of halogen-containing flame retardants has been restricted from the viewpoints of the environment and safety due to problems such as generation of halogen gas generated during combustion and generation of dioxins. Has begun. Particularly, polybromodiphenyl ether-based flame retardants, which have been widely used in the past, have been banned from use in view of substances that generate dioxins. Under such circumstances, there is an increasing demand for commercialization of non-halogen flame-retardant TPU. The method of obtaining a flame-retardant TPU using a non-halogen flame retardant can be roughly classified into the following three methods.

(1) Method using an inorganic compound such as a metal hydrate A metal hydrate represented by aluminum hydroxide and magnesium hydroxide is an epoxy compound utilizing the property of desorbing water during combustion to absorb heat. It is generally used as a flame retardant for resins and unsaturated polyester resins. For example, JP-A-7-1
JP 79682 discloses a method in which a mixture of huntite and hydromagnesite is kneaded in a roll with a TPU and then press-molded. However, as long as this method is followed, it is necessary to add as much as 130 parts of an inorganic substance per 100 parts of TPU, and it is possible to prepare a test piece by using a double roll and a press, but a more practical method such as an extruder , It is impossible to add and knead an inorganic substance in the TPU in the same amount or more as the TPU. Originally, inorganic compounds such as metal hydrates, in order to impart the desired flame retardancy to the flame-retardant resin, it is necessary to add an amount of about the same amount or more as the flame-retardant resin, Even if a closed mixer such as a Banbury mixer is used, the addition of a large amount of the mixer greatly reduces the tensile strength, loses transparency, significantly deteriorates the appearance due to agglomeration of inorganic substances, and makes molding impossible. Have a fatal problem. That is, it has not been possible to obtain a practical flame-retardant TPU using an inorganic compound such as a metal hydrate.

(2) Method using nitrogen-containing compound As the nitrogen-containing compound, melamine, melamine cyanurate, melamine phosphate, melamine sulfate and the like are known.
For example, a method of blending melamine as the only flame retardant with TPU is disclosed in JP-A-5-98150. According to this method, melamine 30 is added to 70 parts of TPU.
By blending the parts, it is possible to achieve excellent flame retardancy that satisfies the UL94 V-0 standard (no cotton ignition in a vertical combustion test). However, the tensile strength of the obtained flame-retardant TPU is reduced to about 1/3 or less of that of TPU alone, and since melamine is a pure white crystal having a melting point of 250 ° C. or higher, the original transparency of the TPU is completely lost. It cannot be used as a molded product. Melamine cyanurate, melamine phosphate, melamine sulfate and the like have been patented for use as flame retardants (see, for example,
No. 85242), only qualitative mention is made of the bleed phenomenon and the flame retardant effect of the flame retardant, and it is almost unlikely that a molded article that can withstand practical use will be obtained as long as these techniques are followed. That is, at present, the method of making the TPU flame-retardant with a nitrogen-containing compound is far from a practical level.

(3) Method Using Phosphorus-Based Flame Retardants Phosphorus-based flame retardants are most widely used as non-halogen flame retardants for polymers. As typical phosphorus-based flame retardants, red phosphorus, ammonium polyphosphate, aromatic phosphorus oligomer, aromatic phosphate, and the like are known. Since red phosphorus uses elemental phosphorus alone as a flame retardant, excellent flame retardancy can be expected with a small amount of red phosphorus added. However, red phosphorus has problems such as spontaneous ignition, generation of toxic phosphine gas during kneading with the TPU, and coloring of the TPU in reddish brown, and cannot be used practically at all. Ammonium polyphosphate is known as a non-halogen flame retardant which is a white fine powder and easy to handle.
No. 9376 discloses a method of adding and blending ammonium polyphosphate and antimony trioxide to TPU. According to this method, it is possible to impart flame retardancy, but the tensile strength of the obtained flame-retardant TPU is reduced to about 1/3 or less of that of the TPU alone and cannot be used as a practical molding material. . Furthermore, ammonium polyphosphate generates an ammonia odor during addition and mixing, making the operation extremely difficult. Also, add ammonium polyphosphate,
The blended flame-retardant TPU has a fatal defect that it has a low melt viscosity, is difficult to mold, and further turns blackish brown in only about one week during a heat aging test. The aromatic phosphorus oligomer has, for example, a characteristic of low volatility, but has a very high viscosity and a viscous liquid due to its large molecular weight, and is difficult to handle. Moreover,
The TPU flame-retarded using an aromatic phosphorus oligomer is colored yellow and has poor wet heat resistance and cannot be used as a practical material. As the aromatic phosphate, triphenyl phosphate, various alkyl-substituted aromatic phosphates, and the like are known. For example, JP-A-9-12775 discloses a flame retardant containing an aromatic phosphate having 12 to 25 carbon atoms derived from a substituent in one molecule. The flame retardant of the publication is
It is characterized by being self-extinguishing by dripping and not causing mold contamination even after continuous molding for a long period of time. However, as the thermoplastic resin which performs flame retardation by adding the flame retardant of the publication, polystyrene, polyolefin, polyvinyl chloride, polyphenylene ether, polyamide, polyester, polyphenylene sulfide, polycarbonate, Although a polymethacrylate-based thermoplastic resin is disclosed, it is said that the composition of the flame retardant and TPU of the publication is excellent not only in flame retardancy but also in moldability, tensile properties, heat aging resistance, wet heat resistance, appearance and the like. Nothing is disclosed or even suggested.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a non-halogen-based flame retardant at a practical level which is excellent in appearance of molded articles, moldability, tensile properties, heat aging resistance, moisture and heat resistance, and flame retardancy. In TPU and its molding material. It is obvious that the target flame retardant performance can be achieved by adding and mixing a certain amount or more of the flame retardant to the TPU. However, in the conventional method as described above, the UL94 V-
A non-halogen flame-retardant TPU composition and its molding material satisfying the 0 standard (no cotton ignition in a vertical combustion test) is not known, and patents and literatures evaluated and evaluated to a practical level are not known. It cannot be done.

[0008] That is, an object of the present invention is to solve all the problems of non-halogen flame-retardant TPU compositions and to improve TPU's original appearance, transparency, moldability, tensile properties, heat aging resistance, wet heat resistance and the like. A non-halogen flame-retardant thermoplastic polyurethane resin composition having excellent flame-retardant performance that satisfies UL94 V-0 standard (no occurrence of cotton ignition in a vertical combustion test) while maintaining the composition and a molding material thereof.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, as a non-halogen flame retardant, a non-halogen flame retardant using an alkyl-substituted aromatic phosphate ester. A flame-retardant thermoplastic polyurethane resin composition that retains the TPU's original appearance, transparency, moldability, tensile properties, heat aging resistance, wet heat resistance, etc. in the case of a composition having a specific melt viscosity. , UL94 V-0
The present inventors have found the surprising fact that they have excellent flame retardancy that satisfies the standard (no cotton ignition occurs in a vertical combustion test), and have completed the present invention. Furthermore, the non-halogen thermoplastic polyurethane resin composition of the present invention is excellent in flame retardancy test after heat aging test, satisfying UL94 V-0 standard (no cotton ignition in vertical combustion test). The present inventors have found a completely unexpected fact that the flame retardant performance is maintained, and have completed the present invention.

That is, the present invention provides a flame-retardant thermoplastic polyurethane resin composition comprising a thermoplastic polyurethane resin (A) and a non-halogen flame retardant (B), wherein the non-halogen flame retardant (B) comprises: An alkyl-substituted aromatic phosphate ester, wherein the flame-retardant thermoplastic polyurethane resin composition has a melt viscosity at 200 ° C. at a shear rate of 10 to 10 ³ sec ⁻¹ of 10 ³ to 10 ⁵ poise. The flame-retardant thermoplastic polyurethane resin composition and the non-halogen flame retardant (B) are represented by the following general formula (I)

[0011]

Embedded image (Wherein Ar ₁ , Ar ₂ , and Ar ₃ represent an alkyl-substituted phenyl group which may be the same or different and have ₃ to 36 carbon atoms derived from the alkyl substituent in one molecule). Is an alkyl-substituted aromatic phosphate ester, preferably a thermoplastic polyurethane resin (A)
The melt viscosity at a shear rate of 10 to 10 ³ sec ^-1 at 00 ° C. should be 10 ³ to 10 ⁵ poise, and the addition amount of the non-halogen flame retardant (B) is preferably the thermoplastic polyurethane resin (A A) a flame-retardant thermoplastic polyurethane resin composition having excellent appearance, transparency, moldability, tensile properties, heat aging resistance and wet heat resistance, characterized by being 10 to 80 parts by weight with respect to 100 parts by weight; A molding material using the same is provided.

Hereinafter, the present invention will be described in detail.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Thermoplastic polyurethane according to the present invention
Tan resin (A) is a polyisocyanate compound (iso
Cyanate component, preferably diisocyanate compound)
And a polyhydroxyl compound (polyol component, preferably
Is a polymer diol) and, if necessary, a chain extender (aliphatic)
Low molecular weight diols such as glycols and aromatic diols)
The composition also preferably contains NCO / OH = 0.9 to 1.1.
/ 1 at a temperature of 200 ° C.
Shear rate at 10 to 10^Threesec^-1Melt viscosity at 10
^Three-10^FivePoise is preferably used.

The polyisocyanate used for producing such a polyurethane resin includes aromatic diisocyanate, aliphatic diisocyanate, alicyclic diisocyanate and modified products of these diisocyanates. Specific examples of such a diisocyanate include, for example, those described in JP-A-53-42234. For example, hexamethylene diisocyanate, isophorone diisocyanate, xylene diisocyanate, cyclohexane diisocyanate, pyridine diisocyanate, toluidine diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,
Examples include 4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, 1,5-naphthylene diisocyanate, and mixtures thereof.

The polyhydroxyl compound used in the production of the polyurethane resin is a so-called polyol, preferably a polyester polyol, a polyether polyol, a polybutadiene diol, a polycarbonate diol and a mixture thereof, and the number average molecular weight of these polyhydroxy compounds. Is preferably 500 to 5
000.

The polyester polyol referred to here is:
Examples include a condensate of a polyhydric alcohol and a polybasic carboxylic acid, a condensate of a hydroxycarboxylic acid and a polyhydric alcohol, and examples of the polyhydric alcohol include ethylene glycol, 1,2-propylene glycol, and 1,3. -Propylene glycol, 2,3-butylene glycol, 1,4
-Butylene glycol, 2,2′-dimethyl-1,3-
Glycols such as propanediol, diethylene glycol, 1,5-pentamethylene glycol, 1,6-hexamethylene glycol, cyclohexane-1,4-diol, and cyclohexane-1,4-dimethanol may be used alone or in combination. it can. Polybasic carboxylic acids include succinic acid, maleic acid, adipic acid, glutanic acid, pimelic acid, spearic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid And the like. As a condensate of a hydroxycarboxylic acid and a polyhydric alcohol, castor oil and a reaction product of castor oil with ethylene glycol, propylene glycol, and the like are also useful. Further, as the polyester polyol, polycaprolactone diols obtained by ring-opening addition polymerization of a lactone such as ε-caprolactone in the presence of glycol or the like can also be used. Examples of the polycaprolactone diols include those obtained by addition-polymerizing one or more of the above-mentioned polyhydric alcohols such as ε-caprolactone, δ-valerolactone, β-methyl-δ-valerolactone, and the like. Can be used.

The polyether polyol is a product obtained by addition polymerization of one or more alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran to a compound having two or more active hydrogens, For example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like can be exemplified. Here, as the compound having two or more active hydrogens, for example, in addition to the above-mentioned polyhydric alcohol and polybasic carboxylic acid,
Examples include amines such as ethylenediamine and hexamethylenediamine, polyhydric phenols such as resorcinol and bisphenol, and castor oil.

Examples of the polybutadiene diol include those having a hydroxyl group at the terminal of polybutadiene and those having a hydroxyl group at the terminal of a copolymer of acrylonitrile and styrene.

As the polycarbonate diol, 1,
Examples thereof include reaction products of glycols such as 6-hexanediol and phosgene or ethylene carbonate, and products obtained by reacting them with the acid component and alcohol component.

As the chain extender (a low molecular weight diol such as an aliphatic glycol or an aromatic diol), dihydric alcohols of the above-mentioned polyhydric alcohols are preferable. For example, ethylene glycol, propylene glycol, trimethylene glycol, Aliphatic glycols such as 4-butylene glycol, 1,6-hexanediol, hydroquinone,
Aromatic diols such as resorcin, methylhydroquinone and phenylhydroquinone can be exemplified.
Among them, ethylene glycol, 1,4-butylene glycol, 1,6-hexanediol and the like can be preferably used.

The non-halogen flame retardant (B) in the present invention
Is an alkyl-substituted aromatic phosphate, preferably an aromatic phosphate in which a part of the phenyl group is alkylated. The alkyl group of the alkyl-substituted aromatic phosphate may preferably be straight-chain or branched. Further, it may be cyclic or partially unsaturated. The number of carbon atoms derived from the alkyl substituent in one molecule is arbitrary in the range of 3 to 36. Further, the substitution position of the alkyl group on the phenyl group is not particularly limited to the ortho, meta, and para positions.

The alkyl-substituted aromatic phosphate is represented by the following general formula (I)

[0023]

Embedded image (Wherein Ar ₁ , Ar ₂ , and Ar ₃ represent an alkyl-substituted phenyl group which may be the same or different and have ₃ to 36 carbon atoms derived from the alkyl substituent in one molecule). Compound.

Specific examples of the alkyl-substituted aromatic phosphate include isopropylphenyldiphenyl phosphate (3 carbon atoms derived from the alkyl substituent), t
-Butylphenyl diphenyl phosphate (4);
Bis (isopropylphenyl) phenylphosphate (six), diisopropylphenyldiphenylphosphate (six), bis (t-butylphenyl) phenylphosphate (six), di-t-butylphenyldiphenylphosphate (six) Tris (isopropylphenyl) phosphate (9), bis (diisopropylphenyl) phenylphosphate (12), octylphenyldixylenyl phosphate (12),
Tri-t-butylphenyldiphenylphosphate (12), bis (isopropylphenyl) nonylphenylphosphate (15), bis (di-tert-butylphenyl) phenylphosphate (16), tris (hexylphenyl) phosphate (18), bis (nonylphenyl) phenyl phosphate (18), dioctylphenyl dicresyl phosphate (18),
Bis (triisopropylphenyl) phenyl phosphate (18), tris (di-tert-butylphenyl) phosphate (24), bis (tri-t-butylphenyl) phenyl phosphate (24), tris (triisopropylphenyl) ) Phosphate (27) and tris (tri-t-butylphenyl) phosphate (3)
6) and the like, among which those having 6 to 24 carbon atoms derived from an alkyl substituent are preferred. These may be used alone or in combination of two or more at an arbitrary ratio.

In addition, as long as the properties of the flame-retardant thermoplastic polyurethane resin composition of the present invention are not changed, aromatic phosphate esters such as triphenyl phosphate, resorcinol-bis (diphenyl phosphate), other than those described above, may be used. ), Condensed phosphates such as bisphenol A-bis (dicresyl phosphate), resorcinyl diphenyl phosphate, bisphenol A-diphenyl phosphate, and other unreacted phenol-containing phosphates. Good.

When the number of carbon atoms derived from the alkyl substituent in one molecule of the alkyl-substituted aromatic phosphate ester of the present invention is less than 3, the volatility is high, and the problem of mold contamination and volatilization due to volatilization during molding processing is high. There is a problem that the flame retardancy is insufficient due to the property and the flame retardancy cannot be maintained after the heat aging test. Further, when the number of carbon atoms derived from the alkyl substituent is 3
When it is larger than 6, a problem such as insufficient flame retardancy due to a decrease in the phosphorus content in one molecule occurs.

The non-halogen flame retardant (B) comprising the alkyl-substituted aromatic phosphate ester of the present invention can be obtained by using a partially alkylated phenol as a raw material phenol to obtain an aromatic phosphorus flame retardant which has been widely used. An acid ester such as triphenyl phosphate can be produced stably in exactly the same manner as described in, for example, JP-B-51-10236 and JP-B-53-318.
No. 63, JP-B-63-61313 and the like. Specifically, for example, a method of esterifying 3 moles of phenols with respect to 1 mole of phosphorus oxychloride in the presence of a Lewis acid catalyst. At this time, the reaction may be carried out as a mixture at a specific phenol ratio for producing the target alkyl-substituted aromatic phosphate, or the phenols may be sequentially reacted for each type.

As the alkyl-substituted aromatic phosphate of the present invention, commercially available products such as Leofos (manufactured by Ajinomoto Co.) and Fosflex (manufactured by Akzo Nobel) may be used. These commercial products include flame retardant plasticizers for polyvinyl chloride, flame retardants for phenolic resins,
It is generally used as an extreme pressure additive for lubricating oil.

Some of the alkyl-substituted aromatic phosphate esters of the present invention are used for flame retarding polyurethane foams. As a method of using an alkyl-substituted aromatic phosphate for flame retardation of a polyurethane foam, for example,
It is known from Japanese Patent Publication No. Hei 2-51923, Japanese Patent Publication No. Hei 6-29313, and the like. However, flame-retardant polyurethane foam is a general term for foamed polyurethane having flame retardancy, and is used for cushioning materials such as beds and sofas, sheets and covers having a surface material such as woven or non-woven fabric adhered to the surface. The molding method and the required properties such as flame retardancy, physical properties, appearance and heat aging resistance are completely different from the flame retardant thermoplastic polyurethane resin composition of the present invention. Also,
In this publication, there is no description about thermoplastic polyurethane.

In the flame-retardant thermoplastic polyurethane resin composition of the present invention, the amount of the non-halogen flame retardant (B) comprising an alkyl-substituted aromatic phosphate is added to 100 parts by weight of the thermoplastic polyurethane resin (A). And 10-8
0 parts by weight, preferably 10 to 50 parts by weight, more preferably 15 to 30 parts by weight. If the addition amount is less than 10 parts by weight, the flame retardant performance is insufficient, and the UL 94 V-
If the standard is not satisfied, the melt viscosity decreases, if it is more than 80 parts by weight, there is a problem of drawdown (dripping) at the time of extrusion molding, and burrs and sinks at the time of injection molding. Occurs, and T
The original physical properties of PU, heat aging resistance, etc. are impaired.

For producing the flame-retardant thermoplastic polyurethane resin composition of the present invention, various known methods can be applied. For example, an internal mixer such as a Banbury mixer, an open mixer such as a two-roll mixer, or a continuous mixer such as an extruder can be used. An extruder is preferable when industrial production such as granulation is considered.

Specifically, the non-halogen flame retardant (B) is added to the TPU, mixed with a Henschel mixer or the like, and then supplied to an extruder, heated to 130 to 250 ° C. while pressurizing, and melt-kneaded and extruded. The extrudate is pelletized or pulverized and then subjected to molding. When the non-halogenated flame retardant (B) is in a liquid state, it may be added to the TPU in a molten state using a liquid pressure injection pump and kneaded and extruded.

The non-halogen flame retardant (B) of the present invention
In the production of the thermoplastic polyurethane resin (A), it is also possible to obtain the flame-retardant thermoplastic polyurethane resin composition of the present invention by adding and mixing to the raw material isocyanate component and / or polyol component and then performing a reaction. It is.

The melt viscosity of the flame-retardant thermoplastic polyurethane resin composition of the present invention is determined by a Capillograph 1B manufactured by Toyo Seiki Seisaku-sho at a resin temperature of 200.degree.
The apparent melt viscosity at 0 ³ sec ^-1 . The flame-retardant thermoplastic polyurethane resin composition of the present invention has a melt viscosity in the range of 10 ³ to 10 ⁵ poise. That is, at a shear rate of 10 sec ^-1 10 ³ to 10 ⁵ poise, the composition showing the range of 10 ³ to 10 ⁵ poise at a shear rate of 10 ³ sec ^-1. If the melt viscosity of the flame retardant thermoplastic polyurethane resin composition of the present invention is less than 10 ³ poise,
Drawdown of resin occurs during extrusion molding, and the desired shape of the extruded product cannot be realized. In addition, many burrs are generated during injection molding, which causes a problem of lowering production efficiency. On the other hand, if it is larger than 10 ⁵ poise, the surface of the extruded product becomes uneven, or the resin pressure of the extruder becomes excessively large, so that extrusion cannot be performed mechanically, which is not preferable.

Other flame retardants can be added to the flame retardant thermoplastic polyurethane resin composition of the present invention, if necessary, as long as the effects of the present invention are maintained. For example, aluminum hydroxide, inorganic hydrates such as magnesium hydroxide, antimony trioxide, antimony compounds such as antimony pentoxide, zinc borate, borates such as ammonium borate, molybdenum compounds such as ammonium molybdate, tin oxide, Metal oxides such as zirconium oxide and zinc oxide.

The flame-retardant thermoplastic polyurethane resin composition of the present invention may contain, if necessary, an antioxidant, an ultraviolet absorber, a plasticizer, a lubricant, a stabilizer, and a compound within a range in which the effects of the present invention are maintained. Various additives such as a nucleating agent, a pigment, a dye and a release agent are added to form a molding material.

For molding the flame-retardant thermoplastic polyurethane resin composition of the present invention, molding methods such as injection molding, extrusion molding, hollow molding, blow molding and calender molding can be applied.

The flame-retardant thermoplastic polyurethane resin composition and the molding material of the present invention thus obtained are UL 94
Not only excellent flame retardant performance that satisfies V-0 standard (no cotton ignition in vertical combustion test), but also excellent appearance, transparency, tensile properties, heat aging resistance, heat and humidity resistance, and heat and heat resistance after TPU Widely used for automotive cables, communication cables, mining cables, automotive interior materials, various vehicle interior materials, house interior materials, etc. Can be used for

[0039]

The present invention will be described more specifically with reference to the following examples and comparative examples. However, the following Examples and Comparative Examples do not limit the present invention at all. In the following, parts and percentages are by weight unless otherwise specified. The methods for evaluating the flame retardancy, appearance, transparency, moldability, tensile properties, heat aging resistance, wet heat resistance and the like of the flame retardant thermoplastic polyurethane resin composition are as follows.

"Flame-retardant performance" Injection molding machine OK manufactured by Okuma Iron Works
Injection molding with M60 / 210A and US UL standard 9
A combustion test was performed on an injection molded plate having a thickness of 2 mm in accordance with the 4V test method (vertical combustion test).

V-0 Self-burning time after contact with the flame is within 5 seconds on average, and there is no ignition of absorbent cotton by the dripping material. V-2 Self-burning time after contact with flame is within 25 seconds on average, and ignition of the absorbent cotton by the droplet is difficult. Fuel performance target: V-0

[Measurement of Melt Viscosity] Using a Capillograph 1B (a barrel diameter of 9.55 mmφ) manufactured by Toyo Seiki Seisaku-sho, Ltd.
20mm by capillary of 1mmφ in diameter and 10mm in length
The relationship between the shear rate at 0 ° C. and the melt viscosity was measured.

"Moldability and appearance" 40 mm manufactured by IKG
Tube forming was performed using a φ extruder to obtain a tube having an inner diameter of 6 mm.

The moldability was evaluated for the shape retention of the extruded tube, and the appearance was evaluated by visual observation of the surface appearance (existence of bumps, smoothness, gloss) of the extruded tube. The results were shown in two stages of ○ and ×.

：: The moldability is as good as the TPU alone, there are no bumps, and there is smoothness and gloss. Also, there is no coloring. X: Poor moldability, unevenness observed, lack of smoothness and gloss, coloring.

"Transparency" Injection molding machine OKM manufactured by Okuma Iron Works
Injection molding was performed at 60 / 210A to obtain an injection molded plate having a thickness of 2 mm. The transparency was evaluated by visually observing the injection molded plate. The results were shown in two stages of ○ and ×.

：: Transparency is as good as TPU alone ×: Transparency is poor

"Tensile Properties" Injection molding machine OK manufactured by Okuma Iron Works
Injection molding was performed using M60 / 210A to obtain an injection molded plate having a thickness of 2 mm. A dumbbell-shaped test piece was punched from the injection molded plate, and the tensile strength and the elongation at break were measured according to JIS K6311.

Target value of tensile strength: 8 of TPU simple substance absolute value
0% or more Target value of elongation at break: equal to or more than the absolute value of TPU alone

"Heat aging resistance" Injection molding machine O manufactured by Okuma Iron Works
Injection molding was performed using KM60 / 210A to obtain an injection molded plate having a thickness of 2 mm. A dumbbell-shaped test piece was punched out of the injection molded plate, placed in a gear oven at 100 ° C. and 120 ° C., and subjected to a heat aging test for 14 days.
Tensile strength and elongation at break were measured according to K6311. The degree of coloring of the test piece after the heat aging test was determined by JI.
It measured with the color difference meter based on SZ8722. The results were shown by the degree of yellowing (N value) before and after heat aging.

Target value of tensile strength after heat aging: at 100 ° C., the retention is 70% or more of the origin. At 120 ° C., the retention is at least TPU alone. Target value of elongation at break after heat aging: 100% retention Is 80% or more of the origin. At 120 ° C, the retention rate is 70% or more of the origin. Target value of yellowing degree (N value): 100 ° C, 120 ° C Both N value of TPU alone

"Flame-retardant performance after heat aging test" Injection molding was carried out with an injection molding machine OKM60 / 210A manufactured by Okuma Iron Works, and a combustion test piece was prepared from the obtained injection-molded plate having a thickness of 2 mm, and was heated at 100 ° C. After a 14-day heat aging test was conducted in a gear oven at 120 ° C. and 120 ° C., a combustion test was conducted in accordance with the US UL standard 94V test method (vertical combustion test).

V-0 Self-combustion time after contact with flame is within 5 seconds on average, no ignition of absorbent cotton by dripping material. V-2 Self-combustion time after contact with flame is within 25 seconds on average, ignition of absorbent cotton by dripping material. Target of flame retardancy after aging test: V-0

"Wet heat resistance" Injection molding machine OK manufactured by Okuma Iron Works
Injection molding was performed using M60 / 210A to obtain an injection molded plate having a thickness of 2 mm. A dumbbell-shaped test piece was punched out of the injection-molded plate and placed in a thermo-hygrostat at 80 ° C./95% humidity for 1 hour.
After conducting a 4-day moist heat resistance test, JIS

The tensile strength and elongation at break were measured according to K6311. Target value of tensile strength after moist heat test: Retention is 70 at the origin
% Or more Target value of elongation at break after moisture resistance test: Origin or more

<Production of Alkyl-Substituted Aromatic Phosphate Ester> (Synthesis Example 1) 712 parts of 2,6-diisopropylphenol, 614 parts of phosphorus oxychloride and 2 parts of aluminum chloride were charged into a reactor equipped with a stirring blade and stirred. The mixture was heated to 150 ° C. over 5 hours while heating at 150 ° C. for 2 hours. The reaction mixture was fractionated to obtain 400 parts of 2,6-diisopropylphenylphosphodichloritate. A reaction vessel equipped with stirring blades was charged with 400 parts of 2,6-diisopropylphenylphosphodichloritate, 280 parts of phenol, and 4 parts of aluminum chloride, and heated to 200 ° C. over 5 hours with stirring. Further heating was performed at 200 ° C. for 2 hours. The reaction mixture was fractionated to obtain 440 parts of 2,6-diisopropylphenyldiphenyl phosphate. The obtained 2,6-diisopropylphenyldiphenyl phosphate was a colorless and odorless liquid. This is called "flame retardant 1".

(Synthesis Example 2) A reaction vessel equipped with a stirring blade was charged with 66 parts of phenol and 4 parts of an acid clay catalyst, and heated to 140 ° C. under a nitrogen stream. Propylene was stirred at a flow rate of 1 liter / min instead of nitrogen and continued to flow until no reaction occurred. The resulting isopropyl-substituted phenol product was a mixture consisting of 5% diisopropylphenol and 95% triisopropylphenol. 220 parts of the above isopropyl-substituted phenol mixture, 154 parts of phosphorus oxychloride, and 2 parts of aluminum chloride were charged into a reaction vessel equipped with a stirring blade, and stirred for 5 hours for 150 hours.
C. and then at 150.degree. C. for a further 2 hours. Add 200 parts of phenol and 200 ℃ over 3 hours
Then, the mixture was further heated and stirred at 200 ° C. for 3 hours. The obtained reaction product was purified by distillation to obtain an alkyl-substituted aromatic phosphate mixture containing diisopropyl-substituted phenyl phosphate and triisopropyl-substituted phenyl phosphate. The obtained alkyl-substituted aromatic phosphate mixture was a colorless and odorless liquid. This is called "flame retardant 2".

(Synthesis Example 3) p-
882 parts of nonylphenol, 188 parts of phenol, 306 parts of phosphorus oxychloride and 3 parts of aluminum chloride were charged, heated to 180 ° C. with stirring for 4 hours, and further heated at 180 ° C. for 4 hours. The reaction mixture was fractionated to obtain 940 parts of bis (p-nonylphenyl) phenyl phosphate. The obtained bis (p-nonylphenyl) phenyl phosphate was a colorless and odorless liquid. This is called "flame retardant 3".

(Synthesis Example 4) p-
660 parts of nonylphenol, 150 parts of phosphorus oxychloride and 2 parts of aluminum chloride were charged, heated to 180 ° C. with stirring for 4 hours, and further heated at 180 ° C. for 4 hours. The reaction mixture was fractionated to obtain 640 parts of tris (p-nonylphenyl) phosphate. The obtained tris (p-nonylphenyl) phosphate was a colorless and odorless liquid. This is called "flame retardant 4".

<Production of Flame-Retardant Thermoplastic Polyurethane Resin Composition> (Example 1) A twin-screw extruder manufactured by Nippon Steel Works Co., Ltd. was set to a barrel temperature of 200 ° C. (however, the feeder section was 160 ° C.) and a die temperature of 200 ° C. did. 25 parts of "Flame retardant 1" was added to 100 parts of a thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.) and mixed with a Henschel mixer. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. After cooling, 120 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 2.

(Example 2) A 44 mmφ twin screw extruder manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 205 ° C. 100 parts of a thermoplastic polyurethane resin Pandex T-8190 (manufactured by Dainippon Ink and Chemicals, Inc.) were mixed with 100 parts of an isopropyl-substituted aromatic phosphate (a flame retardant manufactured by Ajinomoto Co., Inc .: Leofos 3)
5) 21 parts were added and mixed with a Henschel mixer.
The obtained mixture is supplied to an extruder and the number of rotations is 120 rpm.
After cooling, 115 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer after cooling. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 2.

Example 3 A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd. was heated to a barrel temperature of 200 ° C. (however, the feeder section 16
0 ° C.) and a die temperature of 200 ° C. To 100 parts of a thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.) was added 21 parts of tertiary butyl-substituted phenyl phosphate (flame retardant manufactured by Akzo Nobel: trade name: Fosflex 71B), and a Henschel mixer. And mixed. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. After cooling, 115 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 2.

Example 4 A reaction vessel equipped with a stirring blade was
43 parts of 1,4-butylene glycol, 354 parts of polytetramethylene glycol (molecular weight: 1,000), 137 parts of isopropyl-substituted aromatic phosphate (flame retardant manufactured by Ajinomoto Co .: Leofos 65, trade name), hindered phenolic antioxidant ( Ciba-Geigy: Irganox 1
010) 2 parts were charged, and dehydration under reduced pressure was performed at 95 ° C. for 1 hour. 214 parts of methylene diphenyl diisocyanate was added to the mixture and stirred to carry out a urethanation reaction. After pouring into a vat and solidifying, it was cured in a furnace at 160 ° C. for 10 minutes. Crush the obtained lump,
A pellet-like flame-retardant thermoplastic polyurethane resin composition was obtained. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 2.

Example 5 A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 205 ° C. 100 parts of thermoplastic polyurethane resin Pandex T-8190 (manufactured by Dainippon Ink and Chemicals, Inc.) are supplied to the extruder, and 26 parts of "flame retardant 2" are extruded using a liquid pressure pump (manufactured by Fuji Techno). And extruded at a rotation speed of 120 rpm. After cooling, 121 parts of a flame-retardant thermoplastic polyurethane resin composition were obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 2.

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[Table 1]

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[Table 2] Results of Table 1

(Comparative Example 1) A 44 mmφ twin screw extruder manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 200 ° C. Aromatic phosphorus oligomer (flame retardant manufactured by Daihachi Chemical Co., Ltd .: CR-747) 2 heated to 100 parts of thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.) 2
Two parts were added and mixed with a Henschel mixer. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. After cooling, 118 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer. Using the composition, measurement of melt viscosity, evaluation of moldability and appearance, and by injection molding plate, flame retardant performance, transparency, tensile properties,
The heat aging resistance, the wet heat resistance, and the like were evaluated. The results are shown in Table 4. The flame-retardant performance was not as high as V-2, and it was colored yellow after the heat aging test, and was further poor in wet heat resistance.

Comparative Example 2 A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 200 ° C. Ammonium polyphosphate (flame retardant: Hostafram AP462, trade name: Hoechst Co.) 6 in 100 parts of thermoplastic polyurethane resin Pandex T-8185 (Dainippon Ink & Chemicals, Inc.) 6
Was added and mixed with a Henschel mixer. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. After cooling, 100 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 4. The flame retardancy was not sufficient, V-2, and the melt viscosity was low, resulting in poor moldability and lack of transparency. Further, after the heat aging test, the test piece was markedly colored black-brown.

(Comparative Example 3) A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 205 ° C. To 100 parts of a thermoplastic polyurethane resin Pandex T-8190 (manufactured by Dainippon Ink and Chemicals, Inc.), 40 parts of "Flame Retardant 3" was added and mixed with a Henschel mixer. The obtained mixture is supplied to an extruder and extruded at a rotation speed of 120 rpm.
After cooling, 135 parts of a flame-retardant thermoplastic polyurethane resin composition was obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 4.
Although the flame retardancy was satisfactory at V-0, the moldability was poor due to the low melt viscosity.

Comparative Example 4 A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 205 ° C. To 100 parts of a thermoplastic polyurethane resin Pandex T-8190 (manufactured by Dainippon Ink and Chemicals, Inc.), 48 parts of "Flame Retardant 4" was added and mixed with a Henschel mixer. The obtained mixture is supplied to an extruder and extruded at a rotation speed of 120 rpm.
After cooling, 140 parts of a flame-retardant thermoplastic polyurethane resin composition were obtained through a pelletizer. Using this composition, measurement of melt viscosity, evaluation of moldability and appearance, and evaluation of flame retardancy, transparency, tensile properties, heat aging resistance, wet heat resistance, and the like were performed using an injection molded plate. The results are shown in Table 4.
Although the flame retardancy was satisfactory at V-0, the moldability was poor due to the low melt viscosity.

(Comparative Example 5) A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 200 ° C. 100 parts of a thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.) and 100 parts of aluminum hydroxide (flame retardant manufactured by Showa Denko KK: trade name: Heidilite H-42T)
Was added and mixed with a Henschel mixer. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. However, the strands were clay-like and could not be taken out, and the resin pressure of the extruder increased to 150 kg / cm ² or more, and extrusion was impossible. , Extrusion was stopped halfway.

(Comparative Example 6) A twin-screw extruder of 44 mmφ manufactured by Nippon Steel Works Co., Ltd.
0 ° C.) and a die temperature of 200 ° C. To 100 parts of a thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.), 30 parts of melamine cyanurate (flame retardant manufactured by Mitsubishi Chemical Corporation: trade name: MCA) was added and mixed with a Henschel mixer. The obtained mixture was supplied to an extruder and extruded at a rotation speed of 120 rpm. However, clogging occurred on a screen of a die head and the resin overflowed from a vent hole.

(Reference Example) Measurement of melt viscosity, evaluation of moldability and appearance using thermoplastic polyurethane resin Pandex T-8185 (manufactured by Dainippon Ink and Chemicals, Inc.), and flame retardancy by injection molding plate , Transparency, tensile properties,
The heat aging resistance, the wet heat resistance, and the like were evaluated. The results are shown in Table 4.

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[Table 3]

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[Table 4] Table 3 results * It was impossible to measure the degree of yellowing due to blackish brown color.

From the results in Tables 2 and 4, the flame-retardant thermoplastic polyurethane resin composition of the present invention retains the original appearance, transparency, moldability, tensile properties, heat aging resistance, wet heat resistance, etc. of the TPU. It is clear that it has excellent flame-retardant performance satisfying UL94 V-0 standard (no cotton ignition in vertical combustion test).

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The flame-retardant thermoplastic polyurethane resin composition of the present invention is a flame-retardant thermoplastic polyurethane resin composition comprising a thermoplastic polyurethane resin (A) and a non-halogen flame retardant (B). A flame-retardant thermoplastic polyurethane resin composition characterized by containing an alkyl-substituted aromatic phosphate as a non-halogen flame retardant (B), and having a specific melt viscosity, so It is possible to provide a non-halogen flame-retardant thermoplastic polyurethane resin composition having excellent flame retardancy while retaining appearance, transparency, moldability, tensile properties, heat aging resistance, moisture and heat resistance, etc. Communication cables, vehicle cables, mining cables, automotive interior materials,
It can be used for applications that dislike generation of halogen gas due to fire, such as various vehicle interior materials and house interior materials. Therefore, the industrial value of the present invention is extremely large.

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[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a shear rate and a melt viscosity of a molding material of the present invention.

[Explanation of symbols]

 1 ... upper limit of melt viscosity 2 ... lower limit of melt viscosity

Claims (5)

[Claims] 1. A flame-retardant thermoplastic polyurethane resin composition comprising a thermoplastic polyurethane resin (A) and a non-halogen flame retardant (B), wherein the non-halogen flame retardant (B) is an alkyl-substituted aromatic compound. A phosphate of the aromatic group,
The melt viscosity of the flame-retardant thermoplastic polyurethane resin composition at 200 ° C. at a shear rate of 10 to 10 ³ sec ^-1 is 10 ³ or more.
A flame-retardant thermoplastic polyurethane resin composition having a particle size of 10 ⁵ poise. 2. The non-halogen flame retardant (B) is represented by the following general formula (I): (Wherein Ar ₁ , Ar ₂ , and Ar ₃ represent an alkyl-substituted phenyl group which may be the same or different and have ₃ to 36 carbon atoms derived from the alkyl substituent in one molecule). The flame-retardant thermoplastic polyurethane resin composition according to claim 1, which is an alkyl-substituted aromatic phosphate ester to be produced. 3. The thermoplastic polyurethane resin (A) comprises 2
The flame-retardant thermoplastic polyurethane resin composition according to claim ¹ , wherein the melt viscosity at a shear rate of 10 to 10 ³ sec ^-1 at 00 ° C is 10 ³ to 10 ⁵ poise. 4. The amount of the non-halogen flame retardant (B) added is:
The amount is 10 to 80 parts by weight based on 100 parts by weight of the thermoplastic polyurethane resin (A).
The flame-retardant thermoplastic polyurethane resin composition according to the above. 5. A molding material comprising the flame-retardant thermoplastic polyurethane resin composition according to claim 1.