JP2003201349A - Fiber-reinforced polyurethane resin composition, molding method and molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide fiber reinforced polyurethane resin moldings which are capable of maintaining mechanical properties such as impact resistance when left under a high temperature and high humidity. <P>SOLUTION: The resin composition comprises a thermoplastic resin, according to need a thermoplastic elastomer, a reinforcing fiber, and a carbodiimide compound such as a bis(2,6-dialkyl substituted-phenyl) carbodiimide. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fiber reinforced polyurethane resin molded article using a fiber reinforced polyurethane resin composition comprising a thermoplastic polyurethane resin, a reinforcing fiber, a carbodiimide compound, and a thermoplastic elastomer optionally added, The molding method and the fiber-reinforced thermoplastic polyurethane resin composition used therefor. The fiber-reinforced polyurethane resin molded article retains mechanical properties such as impact resistance even when kept under high temperature and high humidity.

[0002]

2. Description of the Related Art Thermoplastic polyurethane resin (TPU)
Is low in heat stability among thermoplastic resins,
A relatively low upper limit is given to the temperature during heating and melting. Therefore, the temperature at the time of molding cannot be increased to sufficiently exert the plasticizing effect, resulting in poor moldability. Therefore, it is generally difficult to improve the impact resistance of the thermoplastic polyurethane resin molded product reinforced with glass fiber long fibers (LGF) or the like. Further, the polyurethane resin is not so good in hydrolysis resistance, and even if it can be reinforced with long fibers, if it is left in an environment of high temperature and high humidity, sufficient mechanical properties, especially impact resistance can be maintained. could not.

Japanese Patent Application Laid-Open No. 09-227173 discloses 1 to 5% by weight of a water-soluble polycarbodiimide resin partially having a polyol segment, 1 to 5% by weight of a polyurethane resin,
Silane coupling agent 0.1 to 1% by weight, lubricant 0.0
A sizing agent for glass fibers is disclosed which is characterized by containing 1 to 0.5% by weight. Further, Japanese Patent Laid-Open No. 06-192206 discloses 4,4'-disubstituted bis (2,6-diisopropylphenyl) carbodiimide as an antihydrolyzing agent that is homogeneously dissolved in TPU. JP 09-
In Japanese Patent No. 255752, when a urethane resin is synthesized from diisocyanate and an ester polyol at 50 to 100 ° C., a polycarbodiimide is added at the time of synthesizing the urethane to improve hydrolysis resistance. Is disclosed. The polycarbodiimide used is a diisocyanate for polyurethanes produced using a Ti (OR) ₄ catalyst. However, these references are related to thermoplastic polyurethane resins reinforced with LGF and the like and having excellent impact resistance,
Further, nothing is taught about the retention of impact resistance when left for a certain time in a high temperature and high humidity environment.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fiber reinforced polyurethane resin molded article which retains mechanical properties such as impact resistance when left under high temperature and high humidity.

[0005]

By using a polyurethane resin composition comprising a polyurethane resin, a reinforcing fiber, and a carbodiimide compound such as bis (2,6-dialkyl-substituted phenyl) carbodiimide, the present inventors have found that The inventors have found that these problems can be solved, and completed the present invention.

That is, the first aspect of the present invention is a fiber-reinforced polyurethane resin comprising a thermoplastic polyurethane resin (TPU) and a thermoplastic elastomer (TPE) optionally added, a reinforcing fiber (R), and a carbodiimide compound (C). A composition is provided. A second aspect of the present invention provides the fiber-reinforced polyurethane resin composition according to the first aspect of the present invention, in which the thermoplastic polyurethane resin (TPU) is a polyether polyurethane resin. In a third aspect of the present invention, the reinforcing fiber (R) is selected from the group consisting of glass, carbon, silicon carbide and boron inorganic fibers; stainless metal fibers; aramid, rayon, nylon and cellulose organic fibers. The fiber-reinforced polyurethane resin composition according to the first aspect of the present invention is at least one kind. A fourth aspect of the present invention provides the fiber-reinforced polyurethane resin composition according to the third aspect of the present invention, in which the length of the reinforcing fiber (R) when formed into a pellet is 2 to 50 mm. A fifth aspect of the present invention provides the fiber-reinforced polyurethane resin composition according to the first aspect of the present invention, wherein the carbodiimide compound (C) is bis (2,6-dialkyl-substituted phenyl) carbodiimide. 6th of this invention WHEREIN: The ratio of the carbodiimide compound (C) with respect to a total of 100 weight part of polyurethane resin (TPU) and thermoplastic elastomer (TPE) is 0.01-5 weight part of this invention 1-5. The fiber-reinforced polyurethane resin composition according to any one of 1. The seventh aspect of the present invention is to provide a thermoplastic elastomer (T
PE) is a polyolefin-based thermoplastic elastomer and / or a styrene-based thermoplastic elastomer, and the fiber-reinforced polyurethane resin composition according to the first aspect of the present invention is provided. The eighth aspect of the present invention is a thermoplastic elastomer (TPE).
The fiber-reinforced polyurethane resin composition according to the seventh aspect of the present invention, wherein the melt viscosity index (MFR) is 10 or more. The ninth aspect of the present invention further provides the fiber-reinforced polyurethane resin composition according to any one of the first to eighth aspects of the present invention, which contains an antioxidant. The tenth aspect of the present invention is a molding of a fiber reinforced polyurethane resin molded article, which comprises molding the fiber reinforced polyurethane resin composition according to any one of the first to eighth aspects of the present invention by injection molding, extrusion molding or compression molding. Provide a way. The eleventh aspect of the present invention is the first aspect of the present invention.
To a carbodiimide compound (C) and a reinforcing fiber (R) which is added as necessary, as a part of the components of the fiber-reinforced polyurethane resin composition according to any one of 1 to 8 above, a thermoplastic polyurethane resin (TPU) and / or Or a masterbatch component (M) blended with at least a part of a thermoplastic elastomer (TPE), and a masterbatch component (M)
The method for molding a fiber-reinforced polyurethane resin molded article according to claim 10, wherein the remaining component (D) of the fiber-reinforced polyurethane resin composition is blended with and molded. A twelfth aspect of the present invention provides a fiber-reinforced polyurethane resin molded article obtained by the method for molding a fiber-reinforced polyurethane resin molded article according to the tenth or eleventh aspect of the present invention.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Thermoplastic polyurethane resin (TP
U) Thermoplastic polyurethane resin (TP) used in the present invention
U) is not particularly limited and may be a polyether type or a polyester type, but is preferably a polyether type thermoplastic polyurethane resin.

The starting isocyanate compound used in the TPU is not particularly limited, and conventional ones such as aromatic compounds, aliphatic compounds and alicyclic compounds can be used. As the isocyanate compound, specifically, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, or a mixture thereof, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-
Aromatic diisocyanates such as diphenylmethane diisocyanate, diphenyldimethylmethane diisocyanate, dibenzyl diisocyanate, naphthylene diisocyanate, phenylene diisocyanate, xylene diisocyanate, tetramethyl xylylene diisocyanate; tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1 , 5-diisocyanate, 3-methylpentane-1,
5-diisocyanate, 2,2,4-trimethylhexamethylene
-1,6-diisocyanate and other aliphatic diisocyanates;
There are alicyclic diisocyanates such as isophorone diisocyanate, cyclohexane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated trimethylxylylene diisocyanate. Further, modified products such as adduct modified products, carbodiimide modified products, allophanate modified products, biuret modified products, uretdione modified products, uretoimine modified products and isocyanurate modified products can also be used. These may be used alone or in combination of two or more.

Specific examples of the raw material polyol used in the TPU include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol,
Saturated and unsaturated low molecular weight glycols such as hexanediol, octanediol, and dipropylene glycol; n
-Low molecular weight alkyl glycidyl ethers such as butyl glycidyl ether and 2-ethylhexyl glycidyl ether; high molecular weight polyether glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene ether glycol; the above low molecular glycols and adipic acid, phthalic acid , Isophthalic acid, terephthalic acid,
Maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dimer acid and other dibasic acids or their anhydrides obtained by dehydration condensation Examples thereof include molecular polyester glycols and polymeric polyester glycols obtained by ring-opening polymerization of cyclic ester compounds such as caprolactone. Among them, preferably, high molecular weight polyether glycols, low molecular weight glycols,
Examples include low molecular weight alkyl glycidyl ethers.

Thermoplastic Elastomer (TPE) In the present invention, a thermoplastic elastomer (TP
E) can be added. The TPE is not particularly limited, but a polyolefin thermoplastic elastomer,
Preferable examples are styrene-based thermoplastic elastomers. As a polyolefin-based thermoplastic elastomer,
Block or random copolymer obtained by copolymerizing α-olefin and ethylene, EPR alone (mostly rubber), simple olefin rubber and polypropylene (P
P) or polyethylene (PE) mechanically blended with, those modified with ~ modified with an unsaturated carboxylic acid, and further partially or completely crosslinked the rubber phase. , These are JIS A hardness 5
0 to D hardness 70, tensile elongation at break 100% or more. As the styrene-based thermoplastic elastomer,
Acrylonitrile / butadiene / styrene block copolymer (ABS) or a simple blend of acrylonitrile / styrene block copolymer (AS) and butyl rubber (BR), styrene / butadiene / styrene block copolymer (SBS), hydrogenated styrene / Butadiene / styrene block copolymer (ESBS or SEBS),
Styrene / isoprene / styrene block copolymer (SIS), styrene / ethylene / propylene / styrene block copolymer (SEPS, which corresponds to the hydrogenated product of SIS), and styrene / butadiene chains are formed in a radial shape. Block copolymer ((SB) nX
(N is an integer of 1 to 4 and X is a polyfunctional initiator) and the like. These have a JIS A hardness of 50 to D hardness of 70 and a tensile elongation at break (TBE) of 50% or more. Hurt
Melt viscosity index of TPE (MFR at 224 ° C and 5.0 kgf / cm ² load specified in ASTM D1238)
Is not particularly limited, but one having an MFR of 5 g / 10 minutes or more, preferably 10 g / 10 minutes or more is suitable.

Reinforcing Fiber (R) As the reinforcing fiber (R) used in the present invention, inorganic fibers such as glass, carbon, silicon carbide and boron; metal fibers such as stainless steel; aramid, rayon, nylon and cellulose. And at least one selected from the group consisting of organic fibers. As the reinforcing fiber (R), a fiber having a higher elasticity than at least TPU which is the matrix resin is selected, and a fiber having a large function of strengthening the rigidity of the matrix resin is preferable. That is, glass, carbon and stainless steel are particularly preferable. The reinforcing fiber (R) may be a long fiber or a short fiber, but is preferably a long fiber, and the length of the fiber is 2 to 50 mm, preferably 4 to 25 mm. If necessary, it can be reinforced in a mixed state of long fibers and short fibers.

The types of glass fiber include E-glass,
S-glass, C-glass, AR-glass, T-glass,
Examples thereof include D-glass and R-glass. They are,
A commercially available product can be used, and it is usually in the form of so-called roving, in which a bundle of a plurality of filaments is wound into a coil. Fiber diameter of glass fiber is 3-100μ
m is suitable. If the amount is less than the above range, the glass content is relatively large when the glass content is large, and it becomes difficult to impregnate the resin. If the amount exceeds the above range, the surface appearance of the molded product is significantly deteriorated. The diameter is preferably 4 to 30 μm, particularly preferably 5 to 25 μm, most preferably 9 to 20 μm.
m.

The glass fiber may be surface-treated with a surface-treating agent containing a coupling agent. As the coupling agent, silane coupling agents such as aminosilane, epoxysilane, amidosilane, azidosilane, acrylsilane, titanate coupling agents and mixtures thereof can be used. Among these, aminosilane and epoxysilane are preferable, and aminosilane coupling agent is particularly preferable. The glass fibers may be bundled with a binder containing a surface treatment agent.

As the carbon fiber, either a pitch system made from the residue (pitch) after petroleum refining or a PAN system made from polyacrylonitrile can be used.
The ones currently on the market and relatively easily available are P
It is an AN-based carbon fiber. Carbon fibers are also commercially available in the form of rovings wound in a coil shape, and the carbon fiber diameter is preferably 5 to 7 μm. In the case of long fibers, if the length is less than 5 μm, it becomes difficult to impregnate the resin because the number of fibers is relatively increased when the carbon content is high, while the length exceeding 7 μm is not generally commercially available at present. The carbon fiber may be surface-treated with a surface-treating agent containing a binder. The type of binder is not particularly limited, but an epoxy binder is preferable.

As stainless fiber, SUS-304
And SUS-316L are commercially available, and either one or a mixture thereof can be used. When used in a building near the coast, etc., SUS-316L, which has higher corrosion resistance, is preferable because it contains a large amount of chloride ions together with moisture, but is not particularly limited. The stainless fiber may also be in the roving form. The fiber diameter is 6 to
It can be selected from any of 35 μm, but for the same reason as in the case of glass fiber, 7 to 30 μm is preferable, and 8 to 20 μm.
Those having a size of μm are particularly preferable. Depending on the type, some stainless fibers are sized with paraffin, but long fibers that are sized with paraffin can reduce breakage due to friction of the stainless fibers during impregnation and facilitate fiber bundles. Since the fiber is not opened, it is easy to handle, but it may impair the adhesion (wettability) between the resin and the stainless fiber. Therefore, it cannot be concluded that sizing is preferable. When stainless steel fiber is used, abrasion resistance is improved compared to the case where resin is reinforced by other long fibers, so it should be used particularly preferably in locations such as window frames or door frames where repeated friction occurs. Can be done. When organic fibers are used, weight reduction, which is one of the important factors for window frames and door frames, can be measured, and among these, the case of using cellulosic fibers can obtain the most weight reduction effect. it can.

Carbodiimide Compound (C) The carbodiimide compound (C) used in the present invention is a compound having a carbodiimide group represented by (-N = C = N-) in the molecule, specifically, diisopropylcarbodiimide and dicyclohexyl. Carbodiimide, di-o-
Triylcarbodiimide, diphenylcarbodiimide,
Dioctyldecylcarbodiimide, di-2,6-dimethylphenylcarbodiimide, di-p-triylcarbodiimide, di-p-methoxyphenylcarbodiimide, p-
Phenylene-bis-di-o-triylcarbodiimide, p
-Phenylene-bis-dicyclohexylcarbodiimide, hexamethylene-bis-dicyclohexylcarbodiimide, ethylene-bis-dicyclohexylcarbodiimide, ethylene-bis-diphenylcarbodiimide and other mono- or dicarbodiimide compounds, and poly (4,4 ')
-Diphenylmethanecarbodiimide), poly (3,3 '
-Dimethyl-4,4'-diphenylmethanecarbodiimide), poly (tolylcarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), poly (1,3-diisopropylphenylenecarbodiimide), poly (1-methyl) -3,5-diisopropylphenylenecarbodiimide), poly (1,3,3
Examples thereof include carbodiimide compounds such as 5-triethylphenylenecarbodiimide) and poly (triisopropylphenylenecarbodiimide). These can be used in combination of two or more. Among these, dicyclohexylcarbodiimide, di-2,6-diisopropylphenylcarbodiimide, di-2,6-dimethylphenylcarbodiimide, o-tolylcarbodiimide, poly (4,4′-).
The use of diphenylmethanecarbodiimide), poly (tolylcarbodiimide), poly (phenylenecarbodiimide), poly (triisopropylphenylenecarbodiimide) is preferable, and bis (2,6-dialkyl (C 1-8) -substituted phenyl) carbodiimide is particularly preferable. Considering blooming, the addition amount of these carbodiimide compounds (C) is a matrix resin (thermoplastic polyurethane resin (TPU) and thermoplastic elastomer (TP)).
When the total of (E) and 100) is 100 parts by weight, it is 5 parts by weight or less, preferably 0.01 to 2 parts by weight.

The polyurethane resin composition of the present invention comprises an antioxidant, a heat stabilizer, a light stabilizer, a weather stabilizer, a hydrolysis inhibitor, a plasticizer, within a range that does not impair the object of the present invention.
Even if it contains various resin additives such as colorants, flame retardants, foaming agents, nucleating agents, compatibilizers, powdered inorganic fillers such as talc, silica and pigments, lubricants, spreading agents, etc. I do not care. Therefore, the matrix resin of the fiber-reinforced polyurethane resin composition includes those containing the above-mentioned additives, fillers and the like in addition to the matrix resin. The filler may include whiskers such as potassium whisker titanate, silicon carbide whiskers, graphite whiskers, silicon nitride whiskers, alumina-boron oxide whiskers, and zinc oxide whiskers, in addition to the usual fillers.

The addition of antioxidants and heat stabilizers
Oxidation, coloring, decomposition of resin caused by heat history during production and molding of fiber reinforced polyurethane resin composition pellets,
This is a useful method for suppressing depolymerization. Further, the hydrolysis inhibitor is effective in stably preventing deterioration of mechanical properties and surface appearance when used for a long period of time in a hot and humid environment. For example, in the case of a thermoplastic polyurethane-based resin, a remarkable deterioration preventing effect can be exhibited by adding a carboxylic acid scavenger that traps a carboxylic acid that promotes hydrolysis.

In particular, when the fiber-reinforced polyurethane resin composition of the present invention contains an antioxidant, the hydrolysis resistance effect of the carbodiimide compound (C) is further improved. Preferable antioxidants used include phenolic antioxidants, phosphorus antioxidants, and sulfur antioxidants. As a phenolic antioxidant,
2,6-di-t-butyl-4-methylphenol, 1,
3,5-Tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, tetrakis {3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionyloxymethyl} methane and the like are mentioned, and among them, hindered phenol compounds are preferable, for example, 2,6-di-t-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3 , 5-di-t-butyl-4-hydroxyphenyl)
Propionate, distearyl (3,5-di-t-butyl-4-hydroxybenzyl) phosphonate, 2,2 '
-Methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-)
Butylphenol), bis {3,3-bis (4-hydroxy-3-t-butylphenyl) butyric acid}
Glycol ester, 4,4'-butylidene bis (6-
t-butyl-m-cresol), 2,2'-ethylidene bis (4,6-di-t-butylphenol), 2,2 '
-Ethylidene bis (4-sec-butyl-6-t-butylphenol), 1,1,3-tris (2-methyl-4-)
Hydroxy-5-t-butylphenyl) butane, bis {2-t-butyl-4-methyl-6- (2-hydroxy-3-t-butyl-5-methylbenzyl) phenyl} terephthalate, 1,3,5 -Tris (2,6-dimethyl-
3-hydroxy-4-t-butylbenzyl) isocyanurate, 1,3,5-tris (3,5-di-t-butyl-
4-hydroxybenzyl) isocyanurate, 1,3,5
-Tris (3,5-di-t-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,3,5-
Tris {(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxyethyl} isocyanurate, tetrakis {methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate} methane , 2-t-butyl-4-methyl-6- (2'-acryloyloxy-3'-t-butyl-5'-methylbenzyl) phenol, 3,9-bis (1 ', 1'-dimethyl-
2'-Hydroxyethyl) -2,4,8,10-tetraoxapyro {5,5} undecane, bis {β- (3-t-
Butyl-4-hydroxy-5-methylphenyl)} propionate and the like. Of these, 1, 3, 5
-Tris (2,6-dimethyl-3-hydroxy-4-t
-Butylbenzyl) isocyanurate, tetrakis {methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate} methane and the like are preferable.

Examples of the phosphorus-based antioxidant include alkyl phosphite, alkyl aryl phosphite, alkyl phosphonite, aryl phosphonite, and the like. Specifically, distearyl pentaerythritol diphosphite, tris ( 2,4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenephosphanite, bis (2,4-di-t-butylphenyl) ) Pentaerythritol-diphosphite, bis (2,4-di-t
-Butyl-4-methylphenyl) pentaerythritol-diphosphite, 1,1,3-tris (2-methyl-4)
-Ditridecyl phosphite-5-t-butylphenyl) butane etc. can be illustrated. Specific examples of the sulfur antioxidant include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyldilauryl-3,3'-thiodipropionate, Pentaerythritol tetrakis (3-lauryl thiopropionate) etc. can be mentioned.

Each of these various antioxidants can be used alone, but it is preferable to use either a phosphorus-based antioxidant or a sulfur-based antioxidant together with a phenol-based antioxidant. Thereby, remarkable heat resistance stability of the resin can be obtained. In that case, the preferable blending amount is the matrix resin component (ie, TPU and TPU).
When the total amount of PE is 100 parts by weight, the phenolic antioxidant is 0.2 to 2.5 parts by weight, preferably 0.3 to 2.2 parts by weight.
It is 0 parts by weight, and the compounding ratio of the phenol-based antioxidant and the phosphorus-based or sulfur-based antioxidant is 1/10 to 10/1 (weight ratio), preferably 1/5 to 5/1. Further, a metal halide may be used in combination with the antioxidant. As a preferable metal halide, it is possible to use copper acetate and potassium iodide as a mixture, which can be present as copper iodide in the composition. The blending ratio with the matrix resin is 0.2 to 3.0 parts by weight, preferably 0.3 to 2.0 parts by weight as copper iodide, when the total of the resin components is 100 parts by weight.
Parts by weight.

Masterbatch (M) Since the carbodiimide compound is expensive and its use requiring hydrolysis resistance is limited, some components of the fiber-reinforced polyurethane resin composition are replaced with the masterbatch component (M). This masterbatch component (M) and the masterbatch component (M) of the fiber reinforced polyurethane resin composition
You may make it shape | mold by compounding with the remaining components (D) other than. As the masterbatch component (M), a carbodiimide compound (C) and a reinforcing fiber (R) optionally added are thermoplastic polyurethane resin (TPU).
And / or at least a part of the thermoplastic elastomer (TPE). Usually, the carbodiimide compound (C) and the reinforcing fiber (R) are blended with a part of the thermoplastic polyurethane resin (TPU) to prepare a masterbatch component (M). Specific examples of the masterbatch component (M) include TPU and the compound (C); those in which the reinforcing fiber (R) is further added; Those in which TPE is further added; , Those in which resin additives are mixed, and the like. Specific examples of the resin on the remaining component (D) side include TPU and / or
Or TPE; further containing reinforcing fiber (R);
Further, those in which a resin additive is mixed may be used.

Pellet of Fiber Reinforced Polyurethane Resin Composition The fiber reinforced polyurethane resin composition, or a masterbatch component thereof, is preferably formed into pellets. The pellets can be obtained by a suitable method including a known technique, for example, by a drawing method, that is, a method of impregnating a reinforcing fiber with a matrix resin while drawing a roving of a reinforcing fiber composed of thousands to tens of thousands of filaments. The obtained strand is obtained by cutting. Any method may be used as the method of impregnating the resin. For example, a method in which a reinforcing fiber is impregnated with an emulsion of a matrix resin and coated and then dried, a method in which a powder suspension of the matrix resin is adhered to the reinforcing fiber, dried and heat-impregnated, and a matrix resin dissolved in a solvent is used. After impregnating the reinforcing fiber with the solvent, a method of removing the solvent, a method of heating the mixed fiber of the matrix resin fiber and the reinforcing fiber and impregnating with the molten matrix resin, or a heat-melted matrix resin into a bar, roll, or die. Any method such as impregnation while opening the glass fiber may be used. Of these methods,
The method of impregnating the heated and melted matrix resin while opening the glass fiber on the bar, roll, or die is most preferred because of the simplicity of the apparatus and process. The reinforcing fibers are present in the resulting pellets in the same length and in parallel alignment with the pellets. The pellet contains 5 to 80% by weight of reinforcing fiber, and in the case of masterbatch, 20
~ 80% by weight, and the pellet length is 2 mm or more,
It is 50 mm or less. If it exceeds 80% by weight, the resin cannot be sufficiently impregnated and the production becomes extremely difficult. The content of the reinforcing fiber is preferably 20 to 60% by weight. If the reinforcing fiber content is less than 5% by weight, the effect of adding reinforcing fibers is insufficient. 20 for masterbatches
If it is less than 10% by weight, the advantages of the masterbatch cannot be utilized, which is economically disadvantageous and the product range of the molded product after dilution becomes narrow. If the pellet length is less than 2 mm, the fibers in the molded product become short, and the mechanical properties, especially the impact strength, decrease. When it exceeds 50 mm, high rigidity, high impact, creep resistance, which are characteristics of long fiber reinforced thermoplastic resin,
The vibration fatigue resistance will not be further improved. Instead, clogging due to bridging in the hopper when molding by injection molding, press molding and other molding methods, and master batch of long fiber thermoplastic resin pellets When used as, it is not preferable because segregation occurs. The preferred pellet length is 4 to 30 mm. Particularly preferably 5
It is 15 mm. The shape of the pellet is not particularly limited except the length, and may have a circular cross section, an ellipse, or a quadrangle, for example. When the longest diameter of the cut surface is R1 and the smallest diameter is R2, the shape of R2 should be 50% of R1, and more preferably 60% or more. Is reduced, and bridging or the like is reduced in the molding machine hopper, which is preferable.

Molding Method The fiber-reinforced polyurethane resin composition is usually molded into pellets as described above, and then molded by injection molding, compression molding, injection compression molding, extrusion molding or the like. As a molding device, in order to suppress damage to the reinforcing fibers, molding is performed with a molding device having a plasticizing unit having a screw groove depth of 6 mm or more and a compression ratio of 2.5 or less. The reinforcing fibers in the obtained molded product have a length equivalent to the pellet length even after being subjected to shearing generated in the resin flow path in the molding machine cylinder or the mold or die. Many, and therefore the number average fiber length is usually several to several hundred times higher than that of a molded product using short fiber reinforced resin pellets. Generally, the ratio of the length of a fiber in a molded article to its cross-sectional diameter is cited as an aspect ratio, which is a measure of the degree of contribution to the mechanical properties of the molded article, or the reason why the mechanical properties of the molded article are high. Quoted as. However, due to the recent improvement in the method of improving the adhesion of the reinforcing fiber to the resin, the rigidity such as the bending elastic modulus is improved even with the short fiber reinforced resin. However, impact strength is not clear at present because the mechanism of impact absorption is very complicated, but it is still longer than a certain length (actual final shape given a molded product with an aspect ratio of 50 or more. ) Is reached, the impact strength of the resin is finally improved. Long fiber reinforced polyurethane resin compositions can increase this aspect ratio and therefore the flexural modulus (MPa) of the resin.
Divided by the notched Izod impact value (J / m) yields a ratio of 4
By selecting the resin composition, viscosity, amount of long fibers, fiber type, fiber diameter, etc. of the matrix resin so as to be 0 or less, a high flexural modulus can be exhibited while maintaining a high impact strength. As a result, it is possible to obtain a molded product having a high bending elastic modulus and a high rigidity while maintaining a high impact strength required for a plastic product such as a window frame or a door frame.

Further, the molded product of the present invention may be a foam, and the foaming can remarkably promote the weight reduction of the molded product. The foam may be a closed cell, an open cell or a mixture thereof. Expansion ratio, air bubbles (cells)
The size and the like can be controlled to desired values by adjusting the type and amount of the foaming agent, foam molding conditions, and molding equipment. However, the expansion ratio and the size of the expansion cells have a great influence on the mechanical properties, surface appearance, vibration absorption performance, impact resistance, etc. of the molded product. Preferable expansion ratio (apparent specific gravity of unexpanded molded product x 100 /
The apparent specific gravity of the molded product after foaming is 200% or less, further preferably 180% or less, and more preferably 16%.
It is 0% or less. If the size of the foamed cells is not 50 μm or less, the impact resistance is poor, preferably 30 μm, more preferably 20 μm or less, and particularly preferably 10 μm or less. In the present invention, the following foam molding method called core back or spring back can also be used. That is, a mold in which the cavity space into which the resin is injected changes from a reduced state of a volume smaller than the volume of the completed foamed resin molded product to an expanded state of a volume substantially the same as the volume of the completed foamed resin molded product. In advance, the mold is heated to a temperature not lower than the heat deformation temperature of the resin and lower than the melting temperature of the resin. Next, the resin is heated to a temperature equal to or higher than the melting temperature to be melted, the gas is dissolved in the resin, and then the resin in which the gas is dissolved is injected into the cavity space in the reduced state. After the injection of the resin is completed, the cavity space is expanded to promote the foaming of the resin in the cavity space. Next, after opening the mold,
Remove the molded product from the mold. By this method, the intermediate layer can be surely foamed even in a foamed resin molded product having a small thickness.

Examples of the foaming agent include chemical decomposition foaming agents and physical foaming agents. The chemical decomposition foaming agent is not limited as long as it decomposes by heat to generate gas, and examples thereof include oxalic acid derivatives, azo compounds, hydrazine derivatives, semicarbazides, azide compounds, nitroso compounds, triazoles, ureas and Examples thereof include nitrates, hydrides, carbonates and the like. Examples of the physical foaming agent include foaming agents that are gasified at the molding temperature, for example, low boiling point liquids such as water and alcohol, liquefied gas such as propane, butane and carbon dioxide, supercritical fluid, non-liquefied gas and the like. To be In addition,
In carbon dioxide, it is also possible to pressurize the carbon dioxide above its critical pressure to semi-liquefy (supercritical fluid) and inject it into the molten resin to disperse it. It is also possible to inject and disperse an inert gas such as nitrogen into the molten resin. Regarding the foam molding method with the addition of a foaming agent, in the case of injection molding and / or compression molding, the mold closing, the timing of the mold opening and the opening degree of the mold opening, the resin is cooled and solidified after the resin is filled in the mold. It is possible to control the foaming ratio and the size of the foamed cells by controlling immediately before the operation. Further, a method of controlling the expansion ratio and the size of foam cells by controlling the pressure of the injected gas by applying gas injection can also be used. In the case of extrusion molding, the inside of the die is designed to gradually expand from the extruder side to the resin discharge port, and the expansion ratio can be controlled by the expansion ratio. The size of the foam cells can be adjusted by controlling various factors such as the type of foaming agent, the shape of the extruder screw and the number of revolutions.

[0027]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited thereto. The raw materials used are as follows. (I) Thermoplastic polyurethane resin (TPU): Polyurethane resin: Elastollan HM76D (manufactured by BASF Polyurethane Elastomers), ASTM D1238
MFR at 224 ° C and 5.0kg load specified in 8g
/ 10 minutes (ii) thermoplastic elastomer (TPE) acrylonitrile-butadiene-styrene (ABS) resin: Sebian V-680SF (manufactured by Daicel Polymer Ltd.) AS
MFR at 230 ° C. and 5 kg load defined by TM D1238 is 5 g / 10 min (iii) Carbodiimide compound: bis (2,6-diisopropylphenyl) carbodiimide (iv) Glass fiber bundle: Fiber diameter φ17 μm, single fiber number 40
00 lines, 2200tex (v) antioxidant (AO): tetrakis {methylene-3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionate} methane (vi) Blowing agent (FA): calcium carbonate

In order to check the hydrolysis resistance of the molded product, the following various tests were conducted. The obtained resin composition pellets,
Mold clamping force 150t, screw groove depth of resin introduction part is 1
An ASTM test piece was molded by an injection molding machine which is a plasticizing unit of a uniaxial screw having a compression ratio of 0.5 and a compression ratio of 2.1 to obtain each test piece. Each test piece was annealed in a warm air dryer at 80 ° C for 24 hours, then stored in a desiccator kept at a humidity of 15% RH or less, and the desiccator was left in an air-conditioned room at 23 ° C for 24 hours. The temperature of the test piece was adjusted. The test piece prepared in this way is heated at 80 ° C × 95% R
After aging for 28 days (672 hours) in a constant temperature / humidity bath maintained at H, the following tests were conducted to determine the mechanical properties (tensile strength, bending strength, bending elastic modulus, notched Izod impact strength). The retention rate before and after aging {retention rate (%) = (measured value after aging) × 100 / (measured value before aging)} was calculated. Tensile test: According to ASTM D638. Bending test: According to ASTM D790. Notched Izod Impact Test: ASTM D256
by. Measurement of fiber length of molded product: Tensile test pieces were fired, glass fibers remaining as ash were dispersed almost evenly on a petri dish filled with water, and projected by 10 times with a projector, and transferred. One by one was measured with a digitizer, and the weight average fiber length was calculated as a histogram.

[Example 1] 70 parts by weight of a thermoplastic polyurethane resin Elastolan HM76D, 30 parts by weight of ABS resin Sevian V-680SF as a thermoplastic resin containing a rubber component, and 0.3 parts by weight of a carbodiimide compound alone, The fiber-reinforced polyurethane resin composition blended with each other is melt-kneaded with a twin-screw extruder, impregnated into a glass fiber bundle by a pultrusion method, and the strand is cut to obtain long-fiber-reinforced thermoplastic polyurethane resin composition pellets (glass A concentration of 50% by weight and a pellet length of 11 mm) was obtained. The obtained pellets were molded and the physical properties were evaluated.

Example 2 The same procedure as in Example 1 was carried out except that 100 parts by weight of the thermoplastic polyurethane resin Elastolan HM76D and 0.3 part by weight of the carbodiimide compound alone were added.

[Example 3] Long fiber reinforced thermoplastic polyurethane resin pellets (glass concentration 60% by weight, obtained by melt-kneading thermoplastic polyurethane resin Elastollan HM76D alone and impregnating glass fiber bundles by a pultrusion method Pellet length 11 mm) was mixed at 83.3% by weight, ABS resin Sebian V-680SF as a thermoplastic resin containing a rubber component at 16.7% by weight, and 0.5 parts by weight of a carbodiimide compound alone were mixed and dried before molding. Blend,
Molding was performed in the same manner as in Example 1 except that the glass concentration was adjusted to approximately 50% by weight, and the physical properties were evaluated.

Example 4 The physical properties were evaluated in the same manner as in Example 1 except that 0.5 part by weight of an antioxidant (AO) was added as an additive to the carbodiimide compound.

[Example 5] The antioxidant (A) used in Example 4 was added to the carbodiimide compound as an additive.
Example 1 except that 0.5 parts by weight of O) and 1 part by weight of a foaming agent (FA) were mixed by using a masterbatch containing 10% by weight and the expansion ratio was 1.3 times. Three
The physical properties were evaluated in the same manner as above.

[Comparative Example 1] Long-fiber-reinforced thermoplastic polyurethane resin pellets (glass concentration: 50% by weight, obtained by melt-kneading thermoplastic polyurethane resin Elastollan HM76D alone and impregnating glass fiber bundles by a pultrusion method Physical properties were evaluated in the same manner as in Example 1 except that only pellet length 11 mm) was used.

[Comparative Example 2] A thermoplastic polyurethane resin Elastollan HM76D was melt-kneaded into a long fiber,
Long-fiber reinforced thermoplastic polyurethane resin pellets obtained by dry blending a foaming agent before molding and compounding the amounts shown in Table 1 (glass concentration 60% by weight, pellet length 11 mm)
In the same manner as in Example 1 except that was used, the physical properties were evaluated.

Comparative Example 3 Physical properties were evaluated in the same manner as in Example 3 except that the carbodiimide compound was not added.

The above results are summarized in Table 1. The molded products of the examples show remarkable hydrolysis resistance as compared with the molded products of the comparative examples, and have a high retention rate of mechanical properties even after being stored at high temperature and high humidity for 28 days.

[0038]

[Table 1]

The fiber-reinforced polyurethane resin molded article of the present invention has a notched Izod impact strength retention rate of 90% after holding for 28 days in a thermo-hygrostat at 80 ° C. and RH of 95%. It is above, and it shows that hydrolysis resistance is small.

[0040]

EFFECTS OF THE INVENTION According to the present invention, a fiber reinforced polyurethane resin molded article can be obtained which retains mechanical properties such as impact resistance when left at high temperature and high humidity.

Front page continuation (51) Int.Cl. ⁷ identification code FI theme code (reference) C08K 5/29 C08K 5/29 7/14 7/14 C08L 75/00 C08L 75/00 // B29K 75:00 B29K 75 : 00 105: 12 105: 12 (72) Inventor Hiroyasu Ishizawa 500 Daikami, Yobu, Himeji-ku, Hyogo-ku 500 Daicel Ueno, Marunouchi apartment 321 F-term (reference) 4F070 AA12 AA18 AA53 AC28 AC45 AD02 AE01 FB03 4F072 AB03 AB05 AB06 AB08 AB09 AB10 AB11 AB14 AD04 AD05 AD43 AD54 AF29 AL01 4F201 AA31 AA45 AB06 AB11 AB19 AB25 AC01 AC08 AR12 AR17 BA02 BA03 BC19 BC21 BD04 BL44 BM14 4F206 AA03 AA13 AA31 AA42 AA45 AB16 AB25 AC01 JA07 JF01 JF02 JL02 461 006 002 002 002 002 002 006 002

Claims (12)

[Claims] 1. A thermoplastic polyurethane resin (TPU) and optionally a thermoplastic elastomer (TPU).
PE), a reinforcing fiber (R), and a carbodiimide compound (C), a fiber-reinforced polyurethane resin composition. 2. A thermoplastic polyurethane resin (TPU)
Is a polyether type polyurethane resin, The fiber reinforced polyurethane resin composition of Claim 1. 3. The reinforcing fiber (R) is glass, carbon,
The fiber-reinforced polyurethane resin composition according to claim 1, which is at least one selected from the group consisting of inorganic fibers made of silicon carbide and boron; metal fibers made of stainless steel; organic fibers made of aramid, rayon, nylon, and cellulose. 4. The fiber-reinforced polyurethane resin composition according to claim 3, wherein the reinforcing fiber (R) has a length of 2 to 50 mm when formed into a pellet shape. 5. The fiber-reinforced polyurethane resin composition according to claim 1, wherein the carbodiimide compound (C) is bis (2,6-dialkyl-substituted phenyl) carbodiimide. 6. The ratio of the carbodiimide compound (C) to the total 100 parts by weight of the polyurethane resin (TPU) and the thermoplastic elastomer (TPE) is 0.01 to 5 parts by weight. The fiber-reinforced polyurethane resin composition according to item. 7. The fiber-reinforced polyurethane resin composition according to claim 1, wherein the thermoplastic elastomer (TPE) is a polyolefin-based thermoplastic elastomer and / or a styrene-based thermoplastic elastomer. 8. The fiber-reinforced polyurethane resin composition according to claim 7, wherein the thermoplastic elastomer (TPE) has a melt viscosity index (MFR) of 10 or more. 9. The method according to claim 1, further comprising an antioxidant.
The fiber-reinforced polyurethane resin composition according to any one of items 1 to 8. 10. A method of molding a fiber-reinforced polyurethane resin molded article, which comprises molding the fiber-reinforced polyurethane resin composition according to claim 1 by injection molding, extrusion molding or compression molding. 11. A part of the fiber-reinforced polyurethane resin composition according to any one of claims 1 to 8 is heated with a carbodiimide compound (C) and optionally a reinforcing fiber (R). Plastic polyurethane resin (TPU)
And / or a masterbatch component (M) blended with at least a part of the thermoplastic elastomer (TPE), and the remaining component (D) of the fiber-reinforced polyurethane resin composition is blended with the masterbatch component (M). The method for molding a fiber-reinforced polyurethane resin molded article according to claim 10, wherein the molding is performed by molding. 12. A fiber-reinforced polyurethane resin molded product obtained by the method for molding a fiber-reinforced polyurethane resin molded product according to claim 10 or 11.