JP7011899B2 - Flame-retardant thermoplastic elastomer composition - Google Patents

Description

The present invention relates to a flame-retardant thermoplastic elastomer composition useful for various molded products such as electronic materials, home appliances, electrical equipment, medical tools, packaging materials, stationery and miscellaneous goods, and a flame-retardant molded product made of the composition. ..

Patent Document 1 discloses a resin composition suitable for an insulated wire in which a polyester-based elastomer resin and a modified polystyrene-based elastomer resin are used in combination with melamine cyanurate and a phosphorus-based antioxidant. However, melamine cyanurate and a metal are disclosed. There is no disclosure of concomitant use with hydrates. Further, the blending amount of melamine cyanurate with respect to 100 parts by weight of the base polymer is 3.0 to 10.0 parts by weight, and it is disclosed that if the amount of melamine cyanurate is excessively increased, the mechanical properties of the molded product deteriorate.

Patent Document 2 exemplifies aluminum hydroxide as an inorganic hydrate that can be used for a specific polyethylene terephthalate resin as a composition for a flame-retardant polyester-based decorative sheet, and melamine cyanurate is appropriately blended as desired. Although it is disclosed that aluminum hydroxide can be selected based on the thermal decomposition temperature, there is no description or suggestion, and only those having a decomposition temperature of 200 ° C or less are specifically disclosed. .. Furthermore, there is no specific disclosure of a mode in which aluminum hydroxide and melamine cyanurate are used in combination.

Japanese Unexamined Patent Publication No. 2008-143962 Japanese Unexamined Patent Publication No. 2005-298715

Since the thermoplastic polyester elastomer is flammable in nature, it is necessary to use a flame retardant in combination to impart flame retardancy. However, there is a problem that the mechanical strength and flexibility are lowered by blending the flame retardant.

An object of the present invention is to provide a flame-retardant thermoplastic elastomer composition having an excellent balance between flame retardancy, flexibility and mechanical strength, and a flame-retardant molded product made from the composition.

The present invention
[1] Thermoplastic polyester elastomer A, 1 to 40 parts by mass of triazine compound B with respect to 100 parts by mass of the thermoplastic polyester elastomer A, and metal water having a heating weight loss temperature of 220 to 300 ° C. by 5% by mass. The present invention relates to a flame-retardant thermoplastic elastomer composition containing Japanese product C, and [2] a flame-retardant molded body obtained by molding the flame-retardant thermoplastic elastomer composition according to the above [1].

The flame-retardant thermoplastic elastomer composition of the present invention has an effect of excellent balance between flame retardancy, flexibility and mechanical strength.

The thermoplastic elastomer composition of the present invention is a thermoplastic polyester elastomer A,
It contains a triazine-based compound B and a metal hydrate C having a 5% by mass heating weight loss temperature of 220 to 300 ° C.

Since general polyester-based elastomers start thermal decomposition at around 350 ° C, triazine-based compounds such as melamine cyanurate, which decomposes at the same temperature as polyester-based elastomers, are used as flame retardants suitable for use with polyester-based elastomers. be. However, when a triazine compound is used, there is a problem that the flexibility and the mechanical strength are lowered at the same time as the flame retardancy. On the other hand, the present inventors impair flexibility and mechanical strength even if the amount of melamine cyanurate is reduced by combining a triazine compound with a metal hydrate having a specific pyrolysis temperature. We have found a surprising finding that flame retardancy can be maintained, and have completed the present invention.

It is presumed that the action and effect of the metal hydrate is to decompose and absorb heat before the thermoplastic polyester elastomer in the early stage of combustion, and a sufficient flame retardant effect regardless of whether the decomposition temperature is too high or too low. Cannot be obtained. For example, the 5% by mass decomposition temperature of general aluminum hydroxide is 200 ° C. or less, and the decomposition starts at a temperature much lower than that of polyester elastomer. Therefore, if general aluminum hydroxide is used, not only the flame retardant effect is reduced, but also thermal decomposition starts at the molding temperature (170 ° C to 200 ° C) as a thermoplastic material, so that it can be obtained by foaming in the molding machine. Although the mechanical strength of the resulting elastomer composition may decrease, selecting a metal hydrate having an appropriate decomposition temperature not only provides a flame-retardant effect, but also solves the problem of mechanical strength. be able to.

The thermoplastic elastomer-based elastomer A is a thermoplastic polyester-based elastomer containing a hard segment and a soft segment from the viewpoint of flexibility and moldability.

As the hard segment of the thermoplastic polyester-based elastomer, an aromatic polyester block is preferable.

Aromatic polyester blocks include phthalic acid, terephthalic acid, isophthalic acid, 1,4- or 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'. -Aromatic dicarboxylic acid such as diphenylsulfone dicarboxylic acid, one or more of its alkyl esters and anhydrides, and 2 carbon atoms such as ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol and hexamethylene glycol. It is preferably a crystalline polyester block which is a polycondensate with one or more of the alkylene glycols of ~ 6.

Examples of the soft segment of the thermoplastic polyester-based elastomer include a polyester-type polymer block, a polyether-type polymer block, a polycarbonate-type polymer block, and the like, and among these, a polyether-type polymer block is preferable from the viewpoint of flexibility.

Examples of the polyester type polymer block include polycaprolactone, polyenan lactone, polycaprilolactone, and a polyalkylene ester formed by a condensation reaction between an aliphatic dicarboxylic acid compound and an aliphatic diol. Examples of the polyalkylene ester formed by the condensation reaction of the aliphatic dicarboxylic acid compound and the aliphatic diol include polybutylene adipate and the like.

As the polyether type polymer block, an aliphatic polyether block is preferable, and one mainly composed of polyalkylene ether glycol is more preferable.

The mass ratio (hard segment / soft segment) of the hard segment to the soft segment in the thermoplastic polyester elastomer A is preferably 10/90 to 40/60, more preferably 15/85 to 30/70 from the viewpoint of flexibility. Is.

The D hardness of the thermoplastic polyester elastomer A is preferably 15 to 90, more preferably 20 to 85, still more preferably 25 to 80, from the viewpoint of the flexibility of the thermoplastic elastomer composition.

The A hardness of the thermoplastic polyester elastomer A is preferably 60 to 99, more preferably 65 to 99, still more preferably 70 to 99, from the viewpoint of the flexibility of the thermoplastic elastomer composition.

From the viewpoint of heat resistance, the melting point of the thermoplastic polyester elastomer A is preferably 130 to 240 ° C, more preferably 140 to 230 ° C, and even more preferably 150 to 225 ° C.

Commercially available products of thermoplastic polyester elastomer A include "Keyflex (registered trademark)" (manufactured by LG Chemical Co., Ltd., trade name), "Perprene (registered trademark) P" and "Perprene S" (manufactured by Toyo Spinning Co., Ltd., Product name), "Hitrel (registered trademark)" (manufactured by Toray DuPont Co., Ltd., product name), "Flexmar (registered trademark)" (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., product name) "Lowmod (registered trademark)" (Manufactured by Nippon GE Plastic Co., Ltd., trade name), "Nichigo Polyester (registered trademark)" (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name), "Nouvelle (registered trademark)" (Teijin Kasei Co., Ltd.) Manufactured by, trade name), "Arnitel (registered trademark)" (manufactured by DSM Engineering Plastics Co., Ltd., trade name), etc.

The content of the thermoplastic polyester elastomer A in the composition of the present invention is preferably 40 to 80% by mass, more preferably 60 to 75% by mass.

As the triazine-based compound B, a compound having a triazine group such as melamine and melamine cyanurate is preferable, and in the present invention, melamine cyanurate is preferable.

Melamine cyanurate is a powder obtained by forming a mixture of cyanuric acid and melamine into an aqueous slurry, mixing them well to form salts of both in the form of fine particles, and then filtering and drying this slurry. What is a simple mixture? different. The form of melamine cyanurate is not particularly limited, but it is preferably obtained as a fine powder from the viewpoint of mechanical strength and surface properties of the molded product obtained from the composition of the present invention. Specifically, the powder image taken with a scanning electron microscope (SEM) is preferably analyzed with an image analyzer and has a volume median particle size (D ₅₀ ) of 0.5 to 20 μm, preferably 1 to 15 μm. Some are more preferred. In addition, melamine cyanurate adjusts the surface properties of the particles and changes the affinity with the matrix to suppress the aggregation of the particles, or the surface is surfaced with an organic or inorganic compound for the purpose of increasing the dispersibility in the matrix. Coated ones are preferred. Examples of the compound that coats melamine cyanurate include polyvinyl alcohol-based compounds and silicone-based compounds. In the present specification, the volume median particle size (D ₅₀ ) means the median diameter in the volume-based particle size distribution.

From the viewpoint of flame retardancy, the content of the triazine compound B is 1 to 40 parts by mass, preferably 2 to 25 parts by mass, and more preferably 10 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic polyester elastomer A. 20 parts by mass. In the present invention, flame retardancy can be maintained even with a relatively small amount of triazine compound.

The content of the triazine compound B in the composition of the present invention is preferably 3 to 23% by mass, more preferably 7 to 20% by mass.

Examples of the metal hydrate C include aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite, etc., among which the heating weight loss temperature is 5% by mass. Those with a temperature of 220 to 300 ° C are selected. In the present invention, aluminum hydroxide is preferable from the viewpoint of further improving flame retardancy and mechanical strength.

Aluminum hydroxide having a higher decomposition temperature than general aluminum hydroxide used in the present invention is, for example, in a pressure vessel without adding water to a raw material in which aluminum hydroxide and a reaction retarder that delays boehmite formation are mixed. It can be obtained by a method including a step of heating at a temperature of 170 to 300 ° C. The aluminum hydroxide obtained by such a method has a moderately high 5% by mass heating weight loss temperature, and can further improve the mechanical strength. Examples of commercially available products of aluminum hydroxide produced by the above method include aluminum hydroxide "ALH-3L" and "ALH-F" manufactured by Kawai Lime Industry Co., Ltd.

The 5% by mass heating weight loss temperature of the metal hydrate C is preferably 225 to 290 ° C, more preferably 230 to 280 ° C.

The volume median particle size (D ₅₀ ) of the metal hydrate is preferably 0.5 to 20 μm, more preferably 1 to 15 μm, and even more preferably 2 to 10 μm from the viewpoint of flame retardancy.

The content of the metal hydrate C is preferably 1 to 100 parts by mass, more preferably 2 to 50 parts by mass with respect to 100 parts by mass of the thermoplastic polyester elastomer A from the viewpoint of flame retardancy and mechanical strength. , More preferably 3 to 30 parts by mass.

The content of the metal hydrate C in the composition of the present invention is preferably 1 to 30% by mass, more preferably 3 to 25% by mass.

In the composition of the present invention, the mass ratio of the triazine-based compound B to the metal hydrate C (triazine-based compound B / metal hydrate C) is preferably 1/100 to 45/1, more preferably 10/100. ~ 40/1.

The composition of the present invention may further contain the organic acid compound D. By blending the organic acid compound D, the triazine compound B and the metal hydrate C are more uniformly dispersed in the thermoplastic polyester elastomer A, and the mechanical strength is improved.

As the organic acid compound D, one or more of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 and the acid-modified olefin-based thermoplastic elastomer D2 are preferable from the viewpoint of mechanical strength.

The acid-modified hydrogenated thermoplastic styrene elastomer D1 is a hydrogenated product of a block copolymer composed of a styrene block unit of a polymer composed of a styrene monomer and a conjugated diene block unit of a polymer composed of a conjugated diene. Is preferably acid-modified.

Examples of the styrene-based monomer constituting the styrene block unit include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene and the like.

Examples of the conjugated diene constituting the conjugated diene block unit include butadiene, isoprene, 1,3-pentadiene and the like.

The block copolymer consists of a hard segment composed of a styrene block unit and a soft segment composed of a conjugated diene block unit, and contains a styrene-based monomer unit in the block copolymer from the viewpoint of determining the overall physical properties. The amount is preferably 5 to 70% by mass, more preferably 10 to 60% by mass, still more preferably 20 to 50% by mass.

Hydrogenation of the block copolymer may be partial or total, but the hydrogenation reduces unsaturated bonds and provides heat resistance, weather resistance and mechanical strength. From these viewpoints, the hydrogenation rate is preferably 80% or more, more preferably 90% or more. The hydrogenation rate can be determined by measuring the content of carbon-carbon double bonds derived from the conjugated diene compound in the block copolymer before and after hydrogenation by ¹ H-NMR spectrum and measuring the measured values. can.

Specific examples of the hydrogenated block copolymer include a styrene-ethylene-butylene-styrene block copolymer, a styrene-ethylene / propylene-styrene block copolymer, and a styrene-ethylene-ethylene / propylene-styrene block copolymer. Combined, styrene-isobutylene-styrene block copolymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, pyridine-butadiene rubber, styrene-isoprene rubber, styrene-ethylene copolymer, styrene-butadiene-styrene block copolymer, styrene -Isoprene-styrene block copolymer, poly (α-methylstyrene) -polybutadiene-poly (α-methylstyrene), poly (α-methylstyrene) -polyisoprene-poly (α-methylstyrene), ethylene-propylene Examples include polymers, styrene-chloroprene rubber and the like. These may be used alone or as a mixture of two or more kinds, but from the viewpoint of raw material preparation and workability, styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene. -At least one selected from the group consisting of a styrene block copolymer (SEPS), a styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), and a styrene-isobutylene-styrene block copolymer (SIBS). Is preferable.

The acid modification of the hydrogenated product of the block copolymer is not particularly limited, but can be performed, for example, by introducing a carboxyl group or an acid anhydride group into the hydrogenated product. The introduction of the above-mentioned carboxyl group or acid anhydride group can be carried out according to a method known per se. Specifically, for example, a hydrogen additive and an unsaturated monocarboxylic acid exemplified by acrylic acid, methacrylic acid and the like; an unsaturated dicarboxylic acid exemplified by maleic acid, fumaric acid, hymic acid, itaconic acid and the like; anhydrous. An unsaturated dicarboxylic acid anhydride exemplified by maleic acid, hymic anhydride, itaconic anhydride and the like is heated in the presence of an organic peroxide in the presence or absence of a solvent to cause a graft reaction. Can be obtained by It can also be obtained commercially.

The acid value of the acid-modified hydrogenated thermoplastic styrene elastomer D1 is preferably 0.1 to 50 mgKOH / g, more preferably from the viewpoint of dispersibility of the triazine compound B and the metal hydrate C in the thermoplastic elastomer composition. Is 0.2 to 40 mgKOH / g, more preferably 0.5 to 30 mgKOH / g.

The melt mass flow rate (MFR) of the acid-modified hydrogenated thermoplastic styrene elastomer D1 at 230 ° C. and 2.16 kg is preferably 0.1 to 100 g / 10 min, more preferably 0.1 to 100 g / 10 min from the viewpoint of compatibility with the thermoplastic elastomer composition. It is 0.2 to 80 g / 10 min, more preferably 0.5 to 50 g / 10 min.

The amount of acid modification of the acid-modified hydrogenated thermoplastic styrene elastomer D1 is preferably 0.1 to 10% by mass, more preferably 0.3 to 5.0% by mass, and further preferably 0.5 to 3.0% by mass from the viewpoint of compatibility and workability. Is.

Examples of the acid-modified olefin-based thermoplastic elastomer D2 include ethylene-propylene copolymers, α-olefin copolymer elastomers such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene, and non-polymers thereof. Examples thereof include copolymerized elastomers with conjugated diene, and those in which at least a part of a mixture of two or more of these is acid-modified with an acid component. Examples of the acid component include unsaturated carboxylic acids and anhydrides thereof. Examples of the unsaturated carboxylic acid include (meth) acrylic acid, maleic acid, and an alkyl ester thereof. As the acid component, (meth) acrylic acid alkyl ester and / or (anhydrous) maleic acid are preferable from the viewpoint of easy copolymerization, and the form of the acid component is limited as long as it is copolymerized in the polyolefin resin. It may be any of random copolymerization, block copolymerization, graft copolymerization and the like.

More preferable as the acid-modified olefin-based thermoplastic elastomer D2 is a ternary copolymer composed of ethylene, an acrylic acid alkyl ester (methyl acrylate or ethyl acrylate) and maleic anhydride, and preferably a ternary block copolymer. The acrylic acid alkyl ester may be partially acrylic acid.

The amount of acid modification of the acid-modified olefin-based thermoplastic elastomer D2 is preferably 0.1 to 10% by mass, more preferably 0.3 to 5.0% by mass, from the viewpoint of compatibility and workability.

The melt mass flow rate (MFR) of the acid-modified olefin-based thermoplastic elastomer D2 at 190 ° C. and 2.16 kg is preferably 0.5 to 200 g / 10 min, more preferably 1 to 2 from the viewpoint of compatibility in the thermoplastic composition. It is 150 g / 10 min, more preferably 2 to 100 g / 10 min.

Examples of the organic acid compound D other than the acid-modified hydrogenated thermoplastic styrene elastomer D1 and the acid-modified olefin thermoplastic elastomer D2 include an oxide polyolefin wax and an organic acid. Oxidized polyolefin wax is obtained by oxidizing a polyolefin wax such as polypropylene wax or polyethylene wax by a method such as oxygen oxidation or chemical oxidation, and has a hydroxy group, an aldehyde group, a carboxy group, a carbonyl group, an ester group or a hydroperoxide. A functional group such as an oxide group is contained in the polyolefin skeleton. Examples of the organic acid include saturated fatty acids such as stearic acid, palmitic acid, lauric acid and myristic acid, unsaturated fatty acids such as oleic acid and linoleic acid, and preferably saturated or unsaturated fatty acids having 10 or more and 30 or less carbon atoms. It is a fatty acid.

The acid value of the oxidized polyolefin wax is preferably 0.1 to 200 mgKOH / g, more preferably 0.5 to 100 mgKOH / g, and more preferably 0.5 to 100 mgKOH / g, from the viewpoint of dispersibility of the triazine compound B and the metal hydrate C in the thermoplastic composition. It is preferably 1 to 50 mgKOH / g.

The content of the organic acid compound D is preferably 0.1 to 25 parts by mass, and more preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic polyester elastomer A.

The content of the organic acid compound D in the composition of the present invention is preferably 0.5 to 20% by mass, more preferably 1 to 5% by mass.

The composition of the present invention may further contain an epoxy-based cross-linking agent E. By blending the epoxy-based cross-linking agent, the decrease in mechanical strength due to the hydrolysis of the thermoplastic polyester-based elastomer A molecule is suppressed in the heat-melting process of the production and molding process of the composition of the present invention. That is, the apparent decrease in molecular weight is suppressed by the reaction between the carboxylic acid group or hydroxyl group at the terminal of the hydrolyzed polyester molecule and the epoxy group of the epoxy-based cross-linking agent.

As the epoxy-based cross-linking agent E, an epoxy compound which is a polymer having a styrene structure in the skeleton is preferable.

Examples of commercially available epoxy-based cross-linking agents include Alfon UG series manufactured by Toagosei Co., Ltd., Blemmer CP series manufactured by NOF Corporation, Marproof G series, and John Krill ADR series manufactured by BASF.

The weight average molecular weight of the epoxy-based cross-linking agent E is preferably 3,000 to 30,000, more preferably 5,000 to 15,000, from the viewpoint of moldability of the thermoplastic elastomer composition.

The epoxy value of the epoxy-based cross-linking agent E is preferably 0.2 to 5 meq / g, more preferably 0.3 to 3 meq / g, from the viewpoint of reactivity with the thermoplastic polyester-based elastomer A.

The content of the epoxy-based cross-linking agent E is preferably 0.1 to 10 parts by mass, and more preferably 0.2 to 7 parts by mass with respect to 100 parts by mass of the thermoplastic polyester-based elastomer A.

The content of the epoxy-based cross-linking agent E in the composition of the present invention is preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass.

The composition of the present invention may further contain a phosphorus-based flame retardant F from the viewpoint of improving flame retardancy.

As the phosphorus-based flame retardant, an inorganic type such as red phosphorus and an organic phosphorus type are known, but the phosphorus-based flame retardant F in the present invention has good dispersibility and the decomposition temperature can be selected. Organophosphorus is preferable, and a metal salt of phosphinic acid, a metal salt of a phosphinic acid derivative, and a salt of phosphoric acid and a nitrogen-containing compound are preferable. Examples of the phosphinic acid derivative include diethylphosphine acid and diphenylphosphine acid, and examples of the metal salt include salts of Al, Ti, Zn, Sn and the like. As the salt of phosphoric acid and the nitrogen-containing compound, a salt of an inorganic phosphoric acid (methaphosphoric acid, orthophosphoric acid, pyrophosphoric acid, polyphosphoric acid, etc.) and a nitrogen-containing compound (ammonia, melamine, triazine derivative, diamines, etc.) Can be mentioned.

The phosphorus content in the phosphorus-based flame retardant F is preferably 1 to 40% by mass, more preferably 2 to 30% by mass, and further preferably 5 to 25% by mass.

The 5% by mass heating weight loss temperature of the phosphorus-based flame retardant F is preferably 220 to 600 ° C, more preferably 230 to 500 ° C, and even more preferably 240 to 400 ° C.

The content of the phosphorus-based flame retardant F is preferably 0.1 to 50 parts by mass, and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic polyester elastomer A.

The content of the phosphorus-based flame retardant F in the composition of the present invention is preferably 0.1 to 5% by mass, more preferably 0.5 to 2% by mass.

The composition of the present invention may contain other thermoplastic resins or thermoplastic elastomers as long as the effects of the present invention are not impaired. Among them, the polar elastomer can improve the fusion property of the composition to the polar resin. The polar elastomer is not particularly limited, and examples thereof include NBR (nitrile rubber), polyurethane rubber, epichlorohydrin rubber, polyamide-based thermoplastic elastomer, and acrylic-based thermoplastic elastomer.

The composition of the present invention is, if necessary, a polyolefin resin such as polypropylene and polyethylene, a reinforcing agent such as carbon black, silica, carbon fiber and glass fiber, an inorganic filler and an insulating material as long as the effect of the present invention is not impaired. Heat-conducting fillers, outer lubricants such as calcium stearate, zinc stearate, pigments, antistatic agents, tackifiers, cross-linking aids, heat stabilizers, antioxidants, light stabilizers, UV absorbers, anti-blocking agents , Various additives such as a sealability improving agent, a mold release agent, a coloring agent, and a fragrance may be contained.

The composition of the present invention is, for example, a thermoplastic polyester-based elastomer A, a triazine-based compound B, and a metal hydrate C, and if necessary, an organic acid compound D, an epoxy-based cross-linking agent E, and a phosphorus-based flame retardant F. It is obtained by mixing raw materials containing additives such as the above and solidifying by cooling.

The "mixing" referred to in the present invention is not particularly limited as long as it is a method in which various components are well mixed, and the various components may be dissolved in a soluble organic solvent and mixed, or by melt kneading. It may be mixed.

In the case of melt mixing, a kneader or a general melt extruder can be used, and it is preferable to use a single-screw extruder in order to improve the kneading state. As for the supply to the extruder, various components may be directly supplied to the extruder, or a mixture of various components using a mixing device such as a Henschel mixer in advance may be supplied from one hopper or two hoppers. Each component may be charged and dispensed while being quantified with a screw or the like under the hopper.

The thermoplastic elastomer composition can be used by directly molding the product obtained by melt-mixing into a molded product, or by using pellets or powder before making a molded product to be used as a final product, depending on the application. , Sheets and other intermediate products. For example, it is melt-mixed by an extruder and extruded into a strand, and while being cooled in cold water, it is cut into pellets such as cylinders and rice granules by a cutter. The obtained pellets can usually be made into a predetermined sheet-shaped molded product or mold-molded product by a molding method such as injection molding, extrusion molding, or press molding.

From the viewpoint of flexibility, the A hardness of the thermoplastic elastomer composition of the present invention is preferably 99 or less, more preferably 97 or less, still more preferably 95 or less. Further, it is preferably 60 or more, more preferably 65 or more, and further preferably 70 or more.

Further, the D hardness of the thermoplastic elastomer composition of the present invention is preferably 70 or less, more preferably 60 or less, still more preferably 50 or less, from the viewpoint of flexibility. Further, it is preferably 15 or more, more preferably 20 or more, and further preferably 25 or more.

A flame-retardant molded product can be obtained by appropriately heat-molding the thermoplastic elastomer composition of the present invention according to a conventional method. The application of the flame-retardant molded product obtained by heat-molding the thermoplastic elastomer composition of the present invention is not particularly limited, and general styrene-based elastomers, polyolefin-based elastomers, polyurethane-based elastomers, polyamide-based elastomers, etc. It can be used in fields where acrylic elastomers, polyester elastomers and the like are used.

As the apparatus used for producing a flame-retardant molded product using the thermoplastic elastomer composition of the present invention, any molding machine capable of melting the molding material can be used. For example, a kneader, an extrusion molding machine, an injection molding machine, a press molding machine, a blow molding machine, a mixing roll and the like can be mentioned.

The flame-retardant molded product of the present invention preferably has a flame-retardant property conforming to any of V-0, V-1 and V-2 according to the UL94V standard for flammability with a test piece thickness of 2 mm.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. Various physical properties of the raw materials used in Examples and Comparative Examples were measured by the following methods.

<Component A (thermoplastic elastomer)>
[Hard segment / Soft segment (mass ratio)]
The mass ratio of the hard segment to the soft segment is measured by proton NMR measurement at 25 ° C. in a deuterated chloroform solvent using a nuclear magnetic resonance apparatus (DPX-400 manufactured by BRUKER, Germany). Calculated from the signal intensity ratio of methylene peaks adjacent to various oxygen in the structure.

[A hardness]
Measured according to JIS K 6253 Type A.

[D hardness]
Measured according to JIS K 6253 Type D.

[Melting point]
The melting point is defined as the temperature of the melting peak obtained by raising the temperature at 10 ° C / min according to the method specified in JIS K 7121 using a differential scanning calorimetry (DSC) device. When multiple melting peaks appear, the melting peak that appears at a lower temperature is taken as the melting point.

<Component B (triazine compound)>
[Volume medium particle size (D ₅₀ )]
Arbitrarily 100 images of powder taken with a scanning electron microscope (SEM) are extracted with an image analyzer, the particle size distribution is analyzed using the average value of the major axis and minor axis as the particle size, and the volume-based median diameter is determined. The volume median particle size of the diameter (D ₅₀ ).

<Component C (metal hydrate)>
[5% by mass heating weight loss temperature]
Using a thermogravimetric / differential thermal measurement (TG-DTA) device, measure the weight loss rate obtained by raising the temperature at 10 ° C / min in accordance with the method specified by JIS K7120, and measure the weight loss rate (5). Measure the temperature at which mass%) is reached.
[Volume medium particle size (D ₅₀ )]
In the same manner as for component B, the volume-based median diameter is defined as the volume median particle size (D ₅₀ ).

<Component D (organic acid compound)>
[Composition ratio]
Using a nuclear magnetic resonance apparatus (DPX-400 manufactured by BRUKER, Germany), proton NMR measurement was performed at a concentration of 3 to 5 vol% in a deuterated chloroform solvent at 25 ° C, and the signal intensity ratio of various proton peaks in the molecular structure was measured. Calculated from.
[Acid value]
0.2 g of the sample was precisely weighed in an Erlenmeyer flask with branches, 10 mL of benzyl alcohol was added, and the sample was dissolved by heating in a heater at 230 ° C. for 15 minutes under a nitrogen atmosphere. After allowing to cool to room temperature, add 10 mL of benzyl alcohol, 20 mL of chloroform, and a few drops of phenolphthalein solution, and titrate with 0.02 specified KOH solution to determine the acid value.
[Melt Mass Flow Rate (MFR)]
Measured in accordance with ASTM D1238 at 190 ° C or 230 ° C with a nominal load of 2.16 kg. Further, when it is not common to apply the MFR measurement because the melt fluidity is too high, such as a polyolefin oxide wax, the melt fluidity is evaluated by a well-known method such as melt viscosity.
[Amount of acid denaturation]
The base material before denaturation and the blend of organic acid are pressed using a 0.1 mm spacer to measure IR, and the calibration curve is based on the characteristic absorption of carbonyl (1600-1900 cm ^-1 ) and the amount of organic acid charged. Is prepared, and IR measurement (IR measuring instrument: FT-210 manufactured by Horiba Seisakusho) of the pressed plate of the acid-modified product is performed to determine the modified amount (acid content).

<Component E (epoxy-based cross-linking agent)>
[Weight average molecular weight (Mw)]
Using a gel permeation chromatography (GPC) device using tetrohydrofuran as a solvent, the measurement is performed according to the method specified in JIS K7252, and the molecular weight is measured in terms of polystyrene.
[Epoxy value]
Measure according to JIS K 7236.

<Component F (phosphorus flame retardant)>
[Phosphorus content]
SPS1500VR type ICP emission analysis manufactured by Seiko Instruments Co., Ltd. by adding hydrochloric acid to an aqueous solution obtained by heat-decomposing 0.5 g of a sample with a mixed acid of nitric acid and sulfuric acid (concentrated nitric acid / concentrated sulfuric acid (volume ratio): 1/3). Measure using the device.
[5% by mass heating weight loss temperature]
Using a thermogravimetric / differential thermal measurement (TG-DTA) device, measure the weight loss rate obtained by raising the temperature at 10 ° C / min in accordance with the method specified by JIS K7120, and measure the weight loss rate (5). Measure the temperature at which mass%) is reached.

Examples 1-18 and Comparative Examples 1-7
The raw material components were put into a mixer with the formulations (mass ratio) shown in Tables 9 and 10, and were dry-blended.

Details of the raw materials shown in Tables 9 and 10 used in Examples and Comparative Examples are as follows.

Then, the obtained mixture was melt-kneaded with an extruder (continuous kneader) under the following conditions to produce pellets of a thermoplastic composition.
[Melting and kneading conditions]
Extruder: KZW32TW-60MG-NH (manufactured by Technobel Co., Ltd.)
Cylinder temperature: 180-260 ℃
Screw rotation speed: 200-650r / min

The pellets were injection molded under the following conditions to prepare a press sheet having a thickness of 2 mm, a width of 125 mm and a length of 125 mm.

[Injection molding conditions]
Injection molding machine: 100MSIII-10E (trade name, manufactured by Mitsubishi Heavy Industries, Ltd.)
Injection molding temperature: 200 ° C
Injection pressure: 30%
Injection time: 3sec
Mold temperature: 40 ℃

The compositions obtained in Examples and Comparative Examples were evaluated as follows. The results are shown in Tables 9-11.

[Flexibility (A hardness)]
The press sheet was allowed to stand in a constant temperature and humidity chamber (temperature 23 ° C., relative humidity 50%) for 24 hours or more to stabilize the state of the sheet. Three 2 mm thick press sheets were stacked and the A hardness was measured according to JIS K7215 "Plastic Durometer Hardness Test Method".

[Flexibility (D hardness)]
The press sheet was allowed to stand in a constant temperature and humidity chamber (temperature 23 ° C., relative humidity 50%) for 24 hours or more to stabilize the state of the sheet. Three 2 mm thick press sheets were stacked and the D hardness was measured according to JIS K7215 "Plastic Durometer Hardness Test Method".

[Mechanical strength (tensile fracture stress)]
From the press sheet, use a die-cutting machine to prepare the No. 3 test piece (length 20 mm) described in JIS K7113, and use a tensile tester (Autograph AG-50kND type) manufactured by Shimadzu Corporation to 23. The test piece was pulled at a speed of 200 mm / min under a temperature environment of ° C. The stress (MPa) at break of the test piece was recorded as the tensile fracture stress.

〔Flame retardance〕
Using the method of UL94V (standard defined by Under Writers Laboratories Inc in the United States), 5 measurements were made for each sample. The test piece (length 127 mm, width 12.7 mm, thickness 2.0 mm) was molded using a hot press. The test piece was kept vertical, and after indirectly burning a burner fire at the lower end for 10 seconds, the flame was removed, and the time for extinguishing the fire that ignited the test piece was measured. Next, when the fire was extinguished, a second flame contact was performed for 10 seconds, and the time for extinguishing the ignited fire was measured in the same manner as the first time. At the same time, it was evaluated whether or not the cotton under the test piece was ignited by the falling fire, and the ignited one was designated as "Yes". The total burning time of the first and second burning times of the five samples was taken as the total burning time, and the burning rank was given according to the UL-94V standard based on the presence or absence of cotton ignition. V-0 is the highest combustion rank, and the flame retardancy decreases as it becomes V-1 and V-2. For the compositions of Examples 3, 17 and 18, flame retardancy was also measured for a test piece having a thickness of 1.0 mm.
The flame retardancy grade indicates the flame retardant class classified by the UL94V vertical combustion test. However, 5 tests were performed on all samples to make a judgment. The outline of the classification method is as follows. Other details conform to the UL94V standard.
V-0: Total burning time 50 seconds or less, maximum burning time less than 10 seconds per bottle, no flame dripping
V-1: Total burning time 250 seconds or less, maximum burning time less than 30 seconds per bottle, no flame dripping
V-2: Total burning time 250 seconds or less, maximum burning time less than 30 seconds per bottle, with flame dripping

From the above results, the flame-retardant thermoplastic elastomer compositions of Examples 1 to 18 are excellent in all of flexibility, mechanical strength, and flame retardancy as compared with those of Comparative Examples 1 to 7. You can see that there is.
In particular, from the comparison between Example 1 and Comparative Example 3, it can be seen that the general metal hydrate cannot compensate for the decrease in mechanical strength due to the blending of the triazine-based compound, and the flame retardancy also decreases.
Further, as is clear from the comparison between Example 3 and Examples 17 and 18, the addition of the phosphorus-based flame retardant improves the flexibility and flame retardancy, while the comparison between Example 17 and Comparative Example 7 shows. It can be seen that the use of heat-resistant aluminum hydroxide is superior in flame retardancy.

The flame-retardant thermoplastic elastomer composition of the present invention is used for various molded products such as electronic materials, home appliances, electric devices, medical tools, packaging materials, stationery and miscellaneous goods.

Claims (6)

At least selected from the group consisting of a hard segment having a D hardness of 15 to 80 and an A hardness of 60 to 99, which is an aromatic polyester block, and a polyester type polymer block, a polyether type polymer block, and a polycarbonate type polymer block. 1 for 100 parts by mass of the thermoplastic polyester-based elastomer A containing one kind of soft segment in a mass ratio (hard segment / soft segment) of 10/90 to 40/60. It contains up to 40 parts by mass of triazine-based compound B and aluminum hydroxide having a 5% by mass heating loss temperature of 220 to 300 ° C., and the content of the thermoplastic polyester-based polymer A is 60 to 75% by mass. Flame-retardant thermoplastic having a triazine-based compound B content of 7 to 20% by mass, the aluminum hydroxide content of 3 to 25% by mass, a D hardness of 25 to 70, and an A hardness of 60 to 99. Polymer composition. The flame-retardant thermoplastic elastomer composition according to claim 1 , wherein the triazine-based compound B contains melamine cyanurate. The flame-retardant thermoplastic elastomer composition according to claim 1 or 2 , further comprising 1 to 50 parts by mass of an organic acid compound D with respect to 100 parts by mass of the thermoplastic polyester elastomer A. The flame-retardant thermoplastic elastomer composition according to any one of claims 1 to 3 , further comprising 0.1 to 10 parts by mass of an epoxy-based cross-linking agent E with respect to 100 parts by mass of the thermoplastic polyester elastomer A. The flame-retardant thermoplastic elastomer composition according to any one of claims 1 to 4 , further comprising 1 to 50 parts by mass of a phosphorus-based flame retardant F with respect to 100 parts by mass of the thermoplastic polyester elastomer A. A flame-retardant molded product obtained by molding the flame-retardant thermoplastic elastomer composition according to any one of claims 1 to 5 .