JP2012077223A - Fiber-reinforced elastomer and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber-reinforced elastomer which is excellent in modulus, tear strength and productivity; and to provide a method for producing the same.SOLUTION: The fiber-reinforced elastomer is obtained by kneading (A) a fiber-reinforced thermoplastic resin composition and (B) a second elastomer. In this case, the fiber-reinforced thermoplastic resin composition comprises a thermoplastic resin having (a) a polyolefin, (b) a first elastomer, (c) spherical silica which has an average particle size of at most 1 μm and whose water content is at most 1,000 ppm and (d) a polyamide; the component (a), component (b) and component (c) composing a matrix, and the component (d) being dispersed, in the matrix, as a very fine fiber which has an average diameter of at most 1 μm and whose aspect ratio is at least 2 and at most 1,000; and the component (a), component (b), component (c) and component (d) being chemically combined.

Description

  The present invention is used for tire internal members such as tire beets and carcasses, tire external members such as treads and sidewalls, automobile belts such as toothed belts and flat belts or industrial belts, hoses, rubber rolls, rubber crawls, etc. The present invention relates to a fiber-reinforced elastic body and a manufacturing method thereof.

As disclosed in Patent Documents 1 to 4, conventionally, natural fibers, polybutadiene rubber, polyisoprene rubber, ethylene / propylene rubber, nitrile / butadiene rubber, etc., short fibers such as nylon and polyester, or organic fibers having a high elastic modulus. For example, fiber reinforced elastic bodies having improved modulus and strength in which aromatic polyamide short fibers, cellulose fibers and the like are dispersed in a vulcanizable polymer have been produced. At this time, it may be produced by a vulcanization method as necessary.
These fiber-reinforced elastic bodies are used for tire members, automobile belts, industrial members, sports-related goods, and the like.
Further, fiber reinforced elastic bodies having short fibers such as nylon are known.

JP 58-79037 A JP 63-81137 A JP-A-7-278360 JP-A-9-59435

In recent years, automobile-related measures have been promoted as one of the global environmental protections. For example, there are measures to reduce the thickness and weight to improve fuel efficiency, measures by strengthening vehicle performance, environmental measures by a new system by reviewing the vehicle drive system itself, advanced functions to improve fuel efficiency, etc. In the meantime, the development speed has been accelerated.
The same applies to the development of automotive parts. For example, durability such as high output resistance, strength resistance, or high temperature characteristics of automobile members is required. On the other hand, the fiber reinforced elastic body obtained by the method according to Patent Documents 1 to 4 has a problem that the modulus, breaking strength, tearing strength, and the like are insufficient.

On the other hand, in the fiber-reinforced elastic body, it is important to disperse nylon fibers and the like sufficiently uniformly in a vulcanizable rubber polymer. When the dispersion is insufficient, the modulus, strength and the like are reduced. On the other hand, for example, in order to disperse nylon fibers in a vulcanizable rubber polymer, by rolling with a roll or the like, the rubber is subjected to a pretreatment to relieve entanglement between nylon fibers. Is dispersed in a polymer. When pretreatment between nylon fibers is not performed, the kneading time of a banbury, kneader, extruder, etc. is lengthened.
However, the above-described conventional method has been low in productivity and complicated in process, which has led to an increase in cost.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve these problems and provide a fiber-reinforced elastic body excellent in modulus, tear strength and productivity, and a method for producing the same.

To achieve the above object, the present invention provides (a) a polyolefin, (b) a first elastomer, (c) a spherical silica having an average particle size of 1 μm or less and a water content of 1000 ppm or less, and (d) a thermoplastic having a polyamide. Made of resin, component (a), component (b), and component (c) constitute a matrix, in which component (d) has an average diameter of 1 μm or less and an aspect ratio of 2 or more and 1000 or less. (A) a fiber-reinforced thermoplastic resin composition in which the components (a), (b), (c) and (d) are chemically bonded, B) A fiber-reinforced elastic body obtained by kneading a second elastomer and a method for producing the same.
In the present invention, the total amount of the component (b) and the component (B) is 100 parts by weight, the component (a) is 1 to 40 parts by weight, the component (c) is 1 to 50 parts by weight, and the component (d) It is preferable that the ratio of the ultrafine fiber which consists of 1-50 weight part.

The present invention includes those in which at least one of component (b) and composition (B) is vulcanized.
The present invention also includes those vulcanized by adding a vulcanizing agent such as sulfur, peroxide, a resin vulcanizing agent, and a vulcanization aid as required.

(A) Fiber reinforced thermoplastic resin composition and (B) 2nd elastomer used for manufacture of the fiber reinforced elastic body of this invention are demonstrated.
(A) The fiber reinforced thermoplastic resin composition is produced by the following first to third steps. A 1st process adjusts the matrix which consists of a component (a), a component (b), and a component (c). In the second step, the matrix obtained in the first step and the component (d) are melt-kneaded and reacted. In the third step, the kneaded product obtained in the second step is extruded at a temperature equal to or higher than the melting point of component (d), and then stretched and / or rolled at a temperature lower than the melting point of component (d).
In the second step, the reaction is carried out by melt-kneading, and the binder at that time is kneaded in the step of adjusting the matrix in the first step, or the component (d) is at or above the melting point of the component (d). Either a method in which a material kneaded and reacted in advance in a pretreatment is used as a binder may be used.

The component (a) polyolefin preferably has a melting point in the range of 70 to 250 ° C.
Moreover, what has a Vicat softening point of 50 to 200 degreeC, Most preferably, 50-200 degreeC is used. As such, homopolymers and copolymers of olefins having 2 to 8 carbon atoms, copolymers of olefins having 2 to 8 carbon atoms and aromatic vinyl compounds such as styrene, chlorostyrene and α-methylstyrene , An olefin having 2 to 8 carbon atoms and a vinyl acetate copolymer, a copolymer of an olefin having 2 to 8 carbon atoms and acrylic acid or an ester thereof, and a copolymer of an olefin having 2 to 8 carbon atoms and a vinylsilane compound. Preferably used.

  Specific examples include high density polyethylene, linear low density polyethylene, low density polyethylene, polypropylene, ethylene / propylene block copolymer, ethylene / propylene random copolymer, ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer. Polymer, ethylene / acrylic acid copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / propyl acrylate copolymer, ethylene / butyl acrylate copolymer, ethylene / acrylic Examples include acid 2-ethylhexyl copolymer, ethylene / hydroxyethyl acrylate copolymer, ethylene / vinylsilane copolymer, ethylene / styrene copolymer, and propylene / styrene copolymer.

  Particularly preferred among these component (a) polyolefins are high density polyethylene, linear low density polyethylene, low density polyethylene, polypropylene, ethylene / propylene block copolymer, ethylene / propylene random copolymer, ethylene / acetic acid. Examples include vinyl copolymers, ethylene / vinyl alcohol copolymers, ethylene / acrylic acid copolymers, and ethylene / methyl acrylate copolymers, and those having a melt flow index in the range of 0.2 to 50 g / 10 min. It is preferable that only one of these may be used, or two or more may be combined.

Next, the component (b) first elastomer will be described. (B) The first elastomer preferably has a glass transition temperature of 0 ° C. or lower, more preferably −20 ° C. or lower.
These include natural rubber, isoprene rubber, butadiene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, butyl rubber, chlorinated butyl rubber, brominated butyl rubber, nitrile / chloropyrene rubber, nitrile / isoprene rubber, acrylate / butadiene. Rubber, vinylpyridine / butadiene rubber, vinylpyridine / styrene / butadiene rubber, styrene / chloropyrene rubber, styrene / isoprene rubber, carboxylated styrene / butadiene rubber, carboxylated acrylonitrile / butadiene rubber, styrene / butadiene block copolymer, styrene・ Isoprene block copolymer, styrene / isoprene / styrene copolymer, styrene / ethylene / butylene / styrene copolymer, carboxylated styrene / butane Diblock rubber such as enblock copolymer, carboxylated styrene / isoprene block copolymer, styrene / propylene rubber, ethylene / propylene / diene terpolymer, ethylene / butene rubber, ethylene / butene / diene terpolymer Polymethylene type such as coalescence, chlorinated polyethylene, chlorosulfonated polyethylene, polyolefin elastomer such as ethylene / vinyl acetate copolymer, acrylic rubber, ethylene acrylic rubber, polychloroethylene trifluoride, fluoro rubber, hydrogenated nitrile / butadiene rubber, etc. Rubber having an oxygen atom in the main chain, such as a rubber having a main chain, an epichlorohydrin copolymer, an ethylene oxide / epichlorohydrin / allyl glycidyl ether copolymer, and a propylene oxide / allyl glycidyl ether copolymer The Silicone rubber such as phenylmethylsiloxane, polydimethylsiloxane, polymethylethylsiloxane, polymethylbutylsiloxane, etc., rubber having nitrogen atoms and oxygen atoms in the main chain such as nitroso rubber, polyester urethane, polyether urethane, etc. Can be mentioned. Further, those obtained by modifying these rubbers with epoxy or the like, those modified with silane, or those made maleated are also preferred.

The spherical silica having an average particle diameter of 1 μm or less and a water content of 1000 ppm or less of the component (c) is preferably a method for producing true spherical oxide fine particles by utilizing the deflagration phenomenon of metal powder (hereinafter referred to as “Vaporized Metal Combustion Method”). (Abbreviated as VMC method).
Specifically, a method in which metal powder is dispersed in an oxygen stream, oxidized by being ignited, the metal and oxide are vaporized or liquid with the reaction heat, and cooled to form fine oxide particles. Silica produced by
Silica produced by the VMC method is a spherical group of fine spherical particles and has an average particle diameter of 0.2 μm to 2.0 μm, and does not have an agglomerated structure between silicas. In addition, a material characterized by low moisture adsorption and 1000 ppm or less is used.
That is, as the fiber reinforced thermoplastic resin composition, silica produced by the VMC method has an average particle size of 1 μm or less, more preferably an average particle size of 0.5 μm. Used for.

Silica possesses silanol groups. In the fiber reinforced thermoplastic resin composition, a VMC method having a silanol group concentration of 10 μmol / m ³ or less is used. A silanol group concentration of 10 μmol / m ³ or more is not used because it is highly active and the reaction proceeds and is therefore unsuitable for a fiber-reinforced thermoplastic resin composition.
The silanol group of component (c) has a function as a coupling agent. What is the silanol group structure formed from the alkoxy group of the silane coupling agent and the alkoxy group through moisture in the silane coupling agent? It reacts easily. In addition, those preferably used for the condensation reaction with the amide group of component (d) are also used.
In particular, the component (c) is preferably used in combination with a silane coupling agent or as a mixture of three components of a silane coupling agent and an organic peroxide.

The water content in the silica of component (c) is preferably 1000 ppm or less as the water content. Regarding the water content of the silica particles, it is preferable that the content including all of surface adhesion, crystal water and the like is 1000 ppm or less. More preferably, it is 800 ppm or less, Especially preferably, it is 400 ppm or less.
About the average particle diameter of a component (c), 1 micrometer or less is preferable.

  In addition to the VMC method, silica has a wet sedimentation method, a wet gel method, a dry method, a powder melting method, etc., but any method other than the VMC method can easily adsorb moisture and has a moisture content exceeding 1000 ppm. May be. Moreover, even if it uses a water content as 1000 ppm or less after drying, it will become an irregular shape by the aggregation of a silica group. Silica obtained by the powder melting method has a strong tendency not to form aggregates, but many particles having an average particle diameter exceeding 10 μm are often observed. In addition, the particle size distribution is wide and some have a maximum particle size exceeding 50 μm.

When silica is used in the (A) fiber reinforced thermoplastic resin composition, if the particle diameter is 1 μm or more, it tends to be a foreign substance during stretching and / or rolling in the third step of adjusting the extrudate, Component (d) is not preferable because it makes it impossible to form ultrafine fibers of a thermoplastic polymer having an amide group in the main chain. Even if fibers are obtained after stretching / rolling, the aspect ratio increases beyond the range of 2 to 1000, which is not preferable.
In addition, in the third step of stretching and / or rolling at a temperature lower than the melting point of the component (d) when the form of the silica is a shape other than the spherical particles such as an irregular shape or a lump shape due to the aggregation of the silica group, fibers are formed in the third step This is not preferable because it is an unstable process.
For the above reason, as the component (c) silica, a fiber reinforced thermoplastic resin composition produced by using fine oxide silica produced by the VMC method is preferably used.

Next, the thermoplastic resin having component (d) polyamide will be described. First, a thermoplastic polymer having an amide group in the main chain (hereinafter abbreviated as polyamide) will be described.
The melting point is in the range of 130 to 350 ° C., and is higher than the melting point of the olefin of component (a), more preferably in the range of 160 to 265 ° C. As the component (d), a polyamide that gives tough fibers by extrusion and rolling is preferable.

  Specific examples of polyamides include nylon 6, nylon 66, nylon 6-nylon 66 copolymer, nylon 610, nylon 612, nylon 46, nylon 11, nylon 12, nylon MXD6, polycondensation of xylylenediamine and adipic acid. Body, polycondensate of xylyldiamine and pimelic acid, polycondensate of xylyldiamine and speric acid, polycondensate of xylyldiamine and azelaic acid, polycondensate of xylylenediamine and terephthalic acid, Polycondensate of octamethylenediamine and terephthalic acid, polycondensate of trimethylhexamethylenediamine and terephthalic acid, polycondensate of decamethylenediamine and terephthalic acid, polycondensate of undecamethylenediamine and terephthalic acid, Tetramethyle, a polycondensate of dodecamethylenediamine and terephthalic acid Polycondensates of diamine and isophthalic acid, polycondensates of octamethylene diamine and isophthalic acid, polycondensates of trimethylhexamethylene diamine and isophthalic acid, polycondensates of decamethylene diamine and isophthalic acid, undecamethylene diamine and isophthalic acid Examples thereof include polycondensates with acids and polycondensates of dodecamethylenediamine and isophthalic acid.

  Among these polyamides, particularly preferred are one selected from the group consisting of nylon 6, nylon 66, nylon 6-nylon 66 copolymer, nylon 610, nylon 612, nylon 46, nylon 11 and nylon 12. Or 2 or more types of polyamide is mentioned. These polyamides preferably have a molecular weight in the range of 10,000 to 200,000.

Most of the component (d) is dispersed in the matrix as ultrafine fibers. Specifically, 80% by weight, preferably 90% by weight or more is dispersed as ultrafine fibers.
As a fiber of a component (d), an average fiber diameter is 1 micrometer or less, More preferably, it is the range of 0.01-0.8 micrometer. The aspect ratio is 2 or more and 1000 or less, more preferably 10 to 500.

The component (d) is bonded to any of the components (a), (b), and (c) at the interface. This can be confirmed by the following method, for example. The fiber reinforced thermoplastic resin composition is refluxed with a refluxer such as Soxhlet with a solvent such as methyl ethyl ketone, toluene, xylene or the like that dissolves the component (a) and the component (b), and the component (a) and the component (b) are removed. The remaining component (c) and component (d) are then stirred with 1,2-dichlorobenzene and then allowed to stand gently to separate the suspended fibers from the precipitated silica and further collect the recovered fibers. After washing with acetone, it is weighed after drying, and this weight is defined as Wc.
And the ratio Wc / Wco with respect to Wco is calculated | required for the weight of the component (d) in a composition, and this is calculated | required as a coupling | bonding amount.
From the binding value obtained by this method, it can be considered that component (d) is combined with component (a), component (b), and component (c) in some form. As for the obtained numerical value, the coupling | bonding rate between a component (d), a component (a), a component (b), and a component (c) is 1 to 30 weight%, Especially the range of 5 to 25 weight% is preferable.

  (A) The ratio of the component of a fiber reinforced thermoplastic resin composition is as follows: component (a) 100 parts by weight of polyolefin, component (b) 10 to 600 parts by weight of rubbery polymer having a glass transition temperature of 0 ° C. or less, Component (c) 10 to 500 parts by weight of spherical silica having an average particle diameter of 1 μm or less and a water content of 1000 ppm or less, and component (d) 1 to 400 parts by weight of an ultrafine fiber of a thermoplastic polymer having an amide group in the main chain A composition consisting of parts is preferred.

When the component (b) exceeds 600 parts by weight, it is not preferable because the fiber-reinforced thermoplastic resin composition has strong adhesiveness, poor handling properties, and is difficult to be pelletized.
When the component (c) is 10 parts by weight or less, the elastic modulus is lowered, which is not preferable. On the other hand, if it exceeds 500 parts by weight, it is not preferable in forming the ultrafine fibers of the component (d) of the fiber-reinforced thermoplastic resin composition, and the proportion of the aspect ratio of 2 or more and 1000 or less is significantly reduced. The reproducibility of mechanical properties such as elastic modulus is poor and adversely affects quality.
When the proportion of component (d) exceeds 400 parts by weight, the fine fibers of component (d) are not formed in the fiber-reinforced thermoplastic resin composition.
Even if such a fiber-reinforced thermoplastic resin composition is used, a fiber-reinforced elastic body having a high stress cannot be obtained.

  Below, the binder used for (A) fiber reinforced thermoplastic resin composition is demonstrated. The amount of the binder is 0.1 to 20% by weight, preferably 0.2 to 15% by weight, when the ratio of the binder to the component (d) is 100% by weight of the total amount of the component (d) and the binder. %. When the amount of the binder is 0.1% by weight or less, a strong bond is not obtained, and the composition is inferior in creep resistance, which is not preferable. On the other hand, when the binder is 20% by weight or more, most of the component (d) has a fine spherical or egg-like aspect ratio of 2 or less and does not form ultrafine fibers. For this reason, a composition excellent in modulus cannot be obtained.

  As binders, silane coupling agents, titanate coupling agents, novolak-type alkylphenols, formaldehyde initial condensates, resol-type alkylphenol formaldehyde initial condensates, novolac-type formaldehyde initial condensates, resol-type formaldehyde initial condensates, unsaturated carboxylic acids Ordinarily used ones such as derivatives thereof can be used. Particularly preferred are silane coupling agents.

  Specific examples of the coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, vinyltriacetylsilane, and γ-methacryloxypropyltrimethoxysilane. , Β- (3,4-epoxycyclohexyl) ethylmethoxysilane, γ-glucidoxypropyltrimethoxysilane, γ-glucidoxypropylmethyldimethoxysilane, γ-glucidoxypropylmethyldiethoxysilane, γ-gluci Doxypropylethyldimethoxysilane, γ-glucidoxypropylethyldiethoxysilane, N-β- (aminoethyl) aminopropyltrimethoxysilane, N-β- (aminoethyl) aminopropyltriethoxysilane, N-β- ( Aminoethyl) aminopropi Rumethyldimethoxysilane, N-β- (aminoethyl) aminopropylethyldimethoxysilane, N-β- (aminoethyl) aminopropylethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyl Trimethoxysilane, γ- “N- (β-methacryloxyethyl) -N, N-dimethylammonium (chloride)” propylmethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and still Examples include diaminosilane. Preferably, a silane coupling agent having any of a methacryloxy group, an amino group, a mercapto group, and a vinyl group is suitable.

  An organic peroxide can be used in combination with the silane coupling agent. The amount of the organic peroxide used is preferably 0.01 to 2.0 parts by weight, more preferably 0.01 to 0.5 parts by weight with respect to 100 parts by weight of the component (a).

The organic peroxide preferably has a half-life temperature of 1 minute in a temperature range higher than the melting point of the component (a) or the melting point of the component (d) by about 20 ° C. from this temperature. Specifically, a one-minute half-life temperature of about 80 to 270 ° C. is preferable.
When a silane coupling agent and an organic peroxide are used in combination, a radical is formed on the molecular chain of the component (a), and this radical reacts with the silane coupling agent, whereby the component (a) and the component ( It is considered that reaction between each component of at least one of b) and component (d) is promoted.

  However, when a natural rubber, an isoprene rubber, a styrene / isoprene / styrene block copolymer, an ethylene / propylene / diene copolymer or the like is used for the component (b), an organic peroxide may not be used. The above rubber has a mechanochemical reaction during kneading, so that molecules in the main chain are cleaved, a -COO group is generated at the end of the main chain, becomes a peroxide, and acts as an organic peroxide. Since it is considered, it is not necessary to use an organic peroxide.

  The amount of the organic peroxide used is in the range of 0.01 to 2.0 parts by weight, but outside the range, 0.01 parts by weight or less is not preferable because the acceleration of the reaction is extremely inferior. Further, when 2.0 parts by weight or more is added, the reaction is excessively promoted alone or between each component such as component (a), component (b), component (d), etc., and the molecular weight is high or simple component Alternatively, cross-linking due to reaction between the components proceeds remarkably and becomes a gelled (lumped) state, making it difficult to produce a fiber-reinforced thermoplastic resin composition.

  Specific examples of the organic peroxide include 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane, 2,2-di- t-butylperoxybutane, 4,4-di-t-butyl-peroxyvaleric acid n-butyl ester, 2,2-bis (4,4-di-t-butylperoxycyclohexane) propane, peroxyneodecanoic acid 2,2,4-trimethylpentyl, 2,2,4-trimethylpentyl peroxyodecanoate, α-cumyl peroxycineodecanoate, t-butyl peroxyneohexanoate, t-butyl peroxypivalate, peroxy T-butyl acetate, t-butyl peroxylaurate, t-butyl peroxybenzoate, t-butyl peroxyisophthalate, etc. That. Among them, those having a one-minute half-life temperature in the range of the melt kneading temperature or about 20 ° C. higher than this temperature, specifically those having a one-minute half-life temperature of 80 to 270 ° C. are preferred.

  In the composition (A) of the present invention, a matrix composed of the component (a), the component (b), and the component (c) is formed. The matrix may have a structure in which the component (b) and the component (c) are dispersed in the form of islands in the component (a), and conversely, the component (a) and the component (c) are component ( b) A structure in which islands are dispersed may be employed. And it is preferable that it is mutually couple | bonded among three components, a component (a), a component (b), and a component (c).

  Next, the manufacturing method of (A) fiber reinforced thermoplastic resin composition is demonstrated. As a method for adjusting the matrix in the first step, the component (a), the component (b), the component (c), and the method of melt-kneading the binder include mixing the component (a) with the melting point of the binder and the component (a). Examples include a method of performing melt kneading at the above temperature and then melt kneading the component (b) and the component (c) at a temperature equal to or higher than the melting point of the component (a). The melt kneading can be performed using a kneading apparatus usually used for resins, rubbers and the like. For example, a Banbury type mixer, a kneader, a pressure type kneader, a kneader extruder, an open roll, a short screw extruder, a twin screw extruder, and the like. Particularly preferred is a twin screw extruder capable of continuous melt kneading in a short time.

The second step will be described. In the second step, the matrix component obtained by melting and kneading the component (a), component (b), component (c) and binder obtained in the first step and the component (d) are melt-kneaded. Alternatively, the matrix component obtained by melting and kneading the component (a), the component (b), and the component (c) in the first step and the component (d) previously kneaded and reacted at a melting point or higher of the component (d) are melt-kneaded.
The second step is modified by an apparatus used for kneading resin, rubber or the like. Specific apparatuses include a Banbury mixer, a kneader, a pressure kneader, a kneader extruder, an open roll, a short screw extruder, a twin screw extruder, and the like. Particularly preferred is a twin screw extruder capable of continuous melt kneading in a short time as in the first step.

The melt kneading temperature in the second step is adjusted as an extrudate by melt kneading at a temperature equal to or higher than the melting point of either component (a) or component (d).
Even when melted and kneaded at a temperature below the melting point of component (d), the kneaded product is remarkably preferable because component (d) is not kneaded or dispersed in the matrix of component (a), component (b), or component (c). Absent.

Next, the third step will be described. In the third step, the extrudate of the second step is stretched and / or rolled at a temperature lower than the melting point of the component (d). The kneaded product obtained in the second step is a spinneret, an inflation die or Drawing or rolling from a T die.
The third step is a step in which the fine particles of the component (d) in the kneaded product in the second step are transformed into fibers by spinning and extrusion. Therefore, both spinning and extrusion must be performed at a temperature equal to or higher than the melting point of component (d). Specifically, the melting is preferably performed at a melting point of the component (d) or a temperature range 20 ° C. higher than the melting point. In order to form a fiber, the kneaded material is subsequently subjected to a stretching treatment by stretching or rolling to obtain a stronger fiber. Accordingly, stretching and rolling are performed at a temperature lower than the melting point of component (d).

In the third step, for example, the kneaded product of the second step is extruded from a spinneret of an extruder and spun into a string shape or a yarn shape, and wound with a winder or the like attached with a bobbin or the like while being drafted. The draft means that the winding speed is higher than the extrusion speed of the kneaded material coming out of the spinneret of an extruder or the like, and winding is performed.
Draft ratio = winding speed / speed of kneaded product coming out of spinneret The draft ratio is preferably in the range of 1.5 to 100, more preferably in the range of 2 to 50.

In addition, the extrudate in the second step can be continuously rolled with a rolling roll or the like. For example, while extruding a kneaded extrudate from an inflation die or a T die, it is wound with a roll or the like while being drafted.
In the third step, the thermoplastic resin composition formed by drafting to form ultrafine fibers can be in various product forms such as string, thread, tape, pellet, etc., but preferably a pellet shape is more preferable. . This is because the fiber reinforced thermoplastic resin composition can be uniformly kneaded with the additional elastomer, that is, the second elastomer, by making it into pellets.

  Next, (B) the second elastomer will be described. As the second elastomer, that is, the additional elastomer, those similar to those used as the first elastomer of the component (b) of the fiber-reinforced thermoplastic resin composition are used. Accordingly, any polymer that is a rubber-like polymer at room temperature, so-called an elastomer, is used as the second elastomer, but preferably has a glass transition temperature of 0 ° C. or less, more preferably − Examples include elastomers of 20 ° C. or lower.

The second elastomer includes natural rubber, isoprene rubber, butadiene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, butyl rubber, chlorinated butyl rubber, brominated butyl rubber, nitrile / chloropyrene rubber, nitrile / isoprene rubber, acrylate / butadiene. Rubber, vinylpyridine / butadiene rubber, vinylpyridine / styrene / butadiene rubber, styrene / chloropyrene rubber, styrene / isoprene rubber, carboxylated styrene / butadiene rubber, carboxylated acrylonitrile / butadiene rubber, styrene / butadiene block copolymer, styrene・ Isoprene block copolymer, styrene / isoprene / styrene copolymer, styrene / ethylene / butylene / styrene copolymer, carboxylated styrene / Tadiene block copolymer, diene rubber such as carboxylated styrene / isoprene block copolymer, styrene / propylene rubber, ethylene / propylene / diene terpolymer, ethylene / butene rubber, ethylene / butene / diene ternary copolymer Polymers, polyolefin elastomers such as chlorinated polyethylene, chlorosulfonated polyethylene, and ethylene / vinyl acetate copolymers, polymethylene such as acrylic rubber, ethylene acrylic rubber, polytrifluoroethylene ethylene, fluororubber, hydrogenated nitrile and butadiene rubber Rubber having a main chain of type, epichlorohydrin copolymer, ethylene oxide / epichlorohydrin / allyl glycidyl ether copolymer, propylene oxide / allyl glycidyl ether copolymer, etc., having an oxygen atom in the main chain Rubber Silicone rubber such as polyphenylmethylsiloxane, polydimethylsiloxane, polymethylethylsiloxane, polymethylbutylsiloxane, etc. Rubber having nitrogen and oxygen atoms in addition to carbon atoms in the main chain, such as nitroso rubber, polyester urethane, polyether urethane, etc. Is mentioned. As the second elastomer, only one kind of these rubbers may be used, or two or more kinds may be combined.
The second elastomer may be the same as or different from the first elastomer.

In the fiber-reinforced elastic body of the present invention, the proportion of polyolefin is 1 to 40 parts by weight, preferably 2 to 30 parts by weight, with respect to the total amount of the first elastomer and the second elastomer of 100 parts by weight. 1 to 50 parts by weight of spherical silica having a water content of 1000 ppm or less at 1 μm or less, preferably 5 to 40 parts by weight, and the proportion of ultrafine fibers made of a thermoplastic polymer having polyamide is 1 to 50 parts by weight, preferably 2 to 50 parts by weight. 35 parts by weight.
When the proportion of polyolefin is more than 40 parts by weight, a fiber-reinforced elastic body without rubber elasticity is not preferable. On the other hand, if the amount is less than 1 part by weight, the physical properties of the fiber-reinforced elastic body are not preferable because the fatigue resistance has a particularly directivity and the physical properties perpendicular to the fiber orientation become low. When the amount of silica exceeds 50 parts by weight, fiber orientation becomes difficult, physical properties such as modulus perpendicular to the fiber orientation vary, and the quality becomes unstable. If the silica is less than 1 weight, the modulus is low, which is not preferable. When the amount of ultrafine fibers is more than 50 parts by weight, only a fiber-reinforced elastic body having a small elongation can be obtained. On the other hand, if it is less than 1 part by weight, only a fiber-reinforced elastic body having a low modulus can be obtained.

  The fiber-reinforced elastic body of the present invention is produced by kneading the above-mentioned (A) fiber-reinforced thermoplastic resin composition and (B) the second elastomer. If the ratio of the polyolefin to the total amount of the first and second elastomers in the obtained fiber-reinforced elastic body, the spherical silica having an average particle diameter of 1 μm or less and a water content of 1000 ppm or less, and the ultrafine fibers is within the above range, The second elastomer is not limited, but the weight ratio of (B) the second elastomer and (A) the fiber-reinforced thermoplastic resin composition is 20/1 to 0.1 / 1, particularly 10/1 to 0.5. A range of / 1 is preferable because the kneading operation is easy.

The kneading temperature of (A) the fiber reinforced thermoplastic resin composition and (B) the second elastomer is that of the thermoplastic resin having the polyamide of component (d) constituting the ultrafine fiber in the fiber reinforced thermoplastic resin composition. A temperature lower than the melting point and higher than the melting point of the polyolefin of component (a) is required. Kneading at a temperature higher than the melting point of the thermoplastic resin having the component (d) polyamide is not preferable because the ultrafine fibers in the fiber-reinforced thermoplastic resin composition melt and deform into spherical particles or the like. Moreover, when knead | mixing at temperature lower than the polyolefin of a component (a), dispersion | distribution of the fine fiber in (A) fiber reinforced thermoplastic resin composition is bad, and fiber reinforced elasticity is not obtained.
The kneading temperature of (A) the fiber reinforced thermoplastic resin composition and (B) the second elastomer is not higher than the melting point of the thermoplastic resin having the polyamide of component (d), preferably 20 ° C. or lower than the melting point temperature, The temperature is higher than the melting point of the polyolefin of component (a), preferably higher than 10 ° C.

  In the kneading, a rubber reinforcing agent such as carbon black, a rubber softening agent such as process oil, a vulcanizing agent, a vulcanizing aid, an anti-aging agent and the like are added and kneaded. The temperature rises during the kneading, but the temperature is controlled as necessary so as not to be higher than the melting point of the thermoplastic resin having the polyamide of component (d). Preferably it is 145-180 degreeC, Although kneading | mixing time is not limited, Preferably it is 1-10 minutes. At this time, various vulcanizing agents and vulcanization aids may be kneaded together at room temperature to 100 ° C. Fully disperse and draw into a sheet. When the obtained sheet is molded and vulcanized, a vulcanized product of a fiber reinforced elastic body is obtained. The amount of the vulcanizing agent at this time is preferably in the range of 0.1 to 5.0 parts by weight, particularly 0.5 to 3.0 parts by weight with respect to 100 parts by weight of the total amount of the first and second elastomers. . The amount of the vulcanization aid is preferably 0.01 to 2.0 parts by weight, particularly preferably 0.1 to 1.0 parts by weight based on 100 parts by weight of the total amount of the first and second elastomers.

As the vulcanizing agent, known vulcanizing agents such as sulfur, organic peroxides, resin vulcanizing agents and the like are used. As the vulcanization aid, aldehyde / ammonia, aldehyde / amine, guanidine, thiourea, thiazole, thiuram, dithiocarbamate, xanthate and the like are used.
The vulcanization temperature when a vulcanizing agent or the like is added to the fiber-reinforced elastic composition of the present invention is preferably about 100 to 180 ° C. However, the vulcanization temperature needs to be lower than the melting point of the thermoplastic resin constituting the ultrafine fibers in the fiber-reinforced elastic composition. When vulcanization is performed at a temperature equal to or higher than the melting point of this thermoplastic resin, (A) the fiber formed at the stage of adjusting the fiber-reinforced thermoplastic resin composition is dissolved, and the fiber-reinforced elastic composition having a high modulus. It is because it cannot be obtained.

  The fiber reinforced elastic composition of the present invention includes various fillers such as carbon black, white carbon, activated calcium carbonate, ultrafine magnesium silicate, clay, zinc white, diatomaceous earth, recycled rubber, powder rubber, ebonite, A stabilizer such as amine / aldehyde, amine / ketone, amine, phenol, imidazole, sulfur-containing antioxidant, phosphorus-containing antioxidant, and various pigments may be included.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to the range of these Examples. In the examples and comparative examples, the fiber reinforced thermoplastic resin composition and the fiber reinforced elastic body were measured as follows.

(1) Observation of dispersion shape of component (d) in fiber reinforced thermoplastic composition Good solvent for rubber of each sample, for example, mixed solvent of o-dichlorobenzene and xylene (weight ratio when first elastomer is EPDM) 50:50) at 100 ° C. to extract and remove the component (a) olefin and the first elastomer of component (b), and after stirring with o-dichlorobenzene, leave it gently and precipitate. It was separated into silica and floating fibers, and the floating fibers were collected and observed with an electron microscope.
On the other hand, for a fiber reinforced thermoplastic composition using hydrogenated acrylonitrile butadiene rubber (hereinafter referred to as HNBR) as the first elastomer, the solvent methyl ethyl ketone was stirred at 50 ° C. to remove HNBR. The fibers were collected by the same operation method as the natural rubber fiber collection method described above, and then observed with an electron microscope.

(2) Measurement of modulus, tensile strength, and elongation at break of fiber reinforced elastic body The fiber reinforced elastic body was punched out into a No. 3 dumbbell and measured according to JISK6251.

"Preparation of fiber reinforced thermoplastic resin composition"
(Sample 1)
As component (a), high-density polyethylene (HDPE M3800 MFR (g / 10 min) 8 made by Keiyo Polyethylene), and as component (b), HNBR (Zetpol 2010L Mooney viscosity 57.5 density (g / cc) 0.950 made by ZEON) 0.950 ), Silica as the component (c) (manufactured by SO-C2 VMC manufactured by Admatex, silica secondary unaggregated structure, average particle size 0.5 μm), and polyamide (hereinafter referred to as nylon 66) as the component (d) (Ube nylon manufactured by Ube Industries) 2026B melting point 265 ° C.).
100 parts by weight of component (a) HDPE, 100 parts by weight of component (b) HNBR, and 40 parts by weight of component (c) of 0.75 parts by weight of γ-methacryloxypropyltrimethoxy with respect to 100 parts by weight of component (b) After melt-kneading 0.1 parts by weight of dicumyl peroxide with respect to silane and the component (a) at a temperature of 170 ° C. higher than the melting point of the component (a) using a Banbury mixer, It was used as a pellet. The obtained pellet was used as a matrix component.

Next, 100 parts by weight of nylon 66 as the component (d) is melt-kneaded with a twin-screw extruder heated to 280 ° C. with respect to 100 parts by weight of the HNBR in 240 parts by weight of the obtained pellets. Then, it was pelletized with a pelletizer while being drawn at a draft ratio of 5 using a take-up machine.
The obtained pellet was stirred with a solvent methyl ethyl ketone at 50 ° C. to remove HNBR, and then refluxed at 100 ° C. in a mixed solvent of o-dichlorobenzene and xylene (weight ratio 50:50). The component (a) olefin was extracted and removed, and further stirred with o-dichlorobenzene, then allowed to stand gently, separated into precipitated silica and floating fibers, and the floating fibers were collected and observed with an electron microscope. It was confirmed that the fibers had an average fiber diameter of 0.2 μm.

(Sample 2)
Sample 2 was prepared and pelletized in the same manner as Sample 1, except that the proportion of the component 66 nylon 66 was increased to 240 parts by weight with respect to 100 parts by weight of the component (b) HNBR.
When the obtained pellets were observed in the same manner as in sample 1, they were confirmed to be fibers having an average fiber diameter of 0.3 μm.

(Sample 3)
The ratio of the component (c) silica was increased to 100 parts by weight with respect to 100 parts by weight of the component (b) HNBR, and the sample 3 was adjusted and pelletized in the same manner as the sample 2.
When the obtained pellets were observed in the same manner as in sample 1, they were confirmed to be fibers having an average fiber diameter of 0.3 μm.

(Sample 4)
Sample 4 was prepared and pelletized in the same manner as Sample 3, except that the component (c) silica was not added.
When the obtained pellets were observed in the same manner as in Sample 1, the fibers were observed and confirmed to be fibers having an average fiber diameter of 0.2 μm.

(Sample 5)
Component (a) is 50 parts by weight of LDPE (F522 MFR 5 grams / 10 min. Made by Ube Maruzen Polyethylene), and the first elastomer of component (b) is EPDM (JSR EP-22 Mooney viscosity 42 density (g / cc) 0.86. ) 100 parts by weight, 50 parts by weight of component (c) silica, 100 parts by weight of component 6 (d) polyamide 6 (hereinafter referred to as nylon 6) Turned into.
The obtained pellet was refluxed at 100 ° C. in a mixed solvent of o-dichlorobenzene and xylene (weight ratio 50:50) to extract component (a) HDPE and component (b) first elastomer EPDM, After removing and further stirring in o-dichlorobenzene, it is allowed to stand gently and separated into precipitated silica and floating fibers. The floating fibers are collected, and the fibers are observed. The fibers having an average fiber diameter of 0.2 μm It was confirmed that.

(Sample 6)
Sample 6 was prepared and pelletized in the same manner as Sample 5, except that the component (c) silica was not used.
When the obtained pellet was observed in the same manner as in Sample 5, the fiber was confirmed to be a fiber having an average fiber diameter of 0.2 μm.
The composition table of Samples 1 to 6 is shown in Table 1.

(Examples 1-6)
Examples 1 to 6 and Comparative Examples 1 and 2 will be described below with reference to Table 2.
As shown in Table 2, the fiber reinforced thermoplastic resin compositions shown in Examples 1 to 6 and Comparative Examples 1 and 2, parts by weight such as the second elastomer (HNBR), carbon black (FEF), zinc white No. 1, stearic acid, an anti-aging agent (Naugard XL-1, Nocrack MBZ), a vulcanizing agent peroxide (Percadox 14/40) and the like were vulcanized according to the formulation shown in Table 2.
The blending procedure is as follows: HNBR and a fiber reinforced thermoplastic resin composition are put into a Brabender plastograph set at 160 ° C. and masticated for 30 seconds, and then carbon black (FEF), zinc white 1, stearic acid, anti-aging agent After kneading for 4 minutes, peroxide was blended on an open roll set at 80 ° C. The resulting blend was vulcanized at 160 ° C. for 30 minutes to obtain a vulcanized product of the fiber reinforced elastic composition.
The ratio of the fibers of nylon 66 to the total of 100 parts by weight of HNBR and HNBR added as the second elastomer in the fiber-reinforced thermoplastic resin composition was in the range of 5 to 30 parts by weight (Examples 1 to 3). 6).
In all of the vulcanizates of Examples 1 to 6, ultrafine fibers of nylon 66 were uniformly dispersed in HNBR.

"Vulcanized physical properties"
As apparent from Table 2, in the vulcanized physical properties of the fiber-reinforced elastic bodies of Examples 1 to 6, the modulus of 100% elongation of the tensile physical properties was 8.5 to 23.8 MPa.
On the other hand, the mixing | blending prescription and mixing | blending procedure of the comparative example 1 were performed similarly to Examples 1-6. At that time, the modulus of 100% elongation of tensile properties was 5.7 MPa, which was a lower modulus than Examples 1-6. This is considered because sample 4 in Table 2 does not contain the component (c) silica (see Table 1), and thus has a low crosslinking density.
In Comparative Example 2, an elastic body was prepared in the same manner as in Example 1 except that the HNBR of the second elastomer was increased to 100 parts by weight without using the fiber-reinforced thermoplastic resin composition. The modulus of 100% elongation of the tensile properties of the obtained elastic body was 3.9 MPa, which was a significantly lower value than Examples 1-6.

(Examples 7 to 9)
As shown in Table 3, component weight parts such as fiber reinforced thermoplastic resin compositions (samples) and second elastomers (EPDM) shown in Examples 7 to 9 and Comparative Examples 3 and 4, and carbon black (HAF) , Naphthenic oil, zinc white No. 1, stearic acid, vulcanization accelerators TS, M, and sulfur were vulcanized.
The blending procedure was as follows: EPDM and a fiber reinforced thermoplastic resin composition were put into a Brabender plastograph set at 140 ° C. and masticated for 30 seconds, and then carbon black (HAF), naphthenic oil, zinc white No. 1, stearic acid, After mixing for 4 minutes, vulcanization accelerators TS, M, and sulfur were blended on an open roll set at 60 ° C. The obtained blend was vulcanized at 160 ° C. for 15 minutes to obtain a vulcanized product of a fiber reinforced elastic composition.

In Examples 7 to 9, the ratio of the fibers of nylon 6 to the total of 100 parts by weight of EPDM and EPDM added as the second elastomer in the fiber-reinforced thermoplastic resin composition is in the range of 7 to 15 parts by weight. there were.
When observed with an electron microscope, all of the vulcanizates of Examples 7 to 9 had nylon 6 ultrafine fibers uniformly dispersed in EPDM.

In Example 10, EPDM in the fiber reinforced thermoplastic resin composition, 80 parts by weight of EPDM added as the second elastomer, and 10 parts by weight of butyl rubber “IIR” (Nippon Butyl Co., Ltd. Butyl 365 ML1 + 8 (125 ° C.) 38) A fiber reinforced elastic body was obtained in the same manner as in Example 7 except that the total amount was 100 parts by weight.
In the vulcanized product of Example 10 as well, all nylon 6 ultrafine fibers were uniformly dispersed in 100 parts by weight of the total amount of EPDM in the fiber reinforced thermoplastic resin composition, EPDM of the second elastomer, and butyl rubber. It was.

"Vulcanized physical properties"
As apparent from Table 3, the modulus in the parallel direction to the fiber direction of 100% elongation in the tensile properties of the vulcanizates of the fiber-reinforced elastic bodies of Examples 7 to 10 was 7.3 to 9.7 MPa. The 100% elongation modulus in the fiber vertical direction was 4.5 to 5.7 MPa. The tensile strength was 12.6 to 14.6 MPa.
Regarding the tear strength, the parallel direction to the fiber orientation direction was 50 to 53 N / mm, while the perpendicular direction to the fiber orientation direction was 54 to 58 N / mm.
The direction perpendicular to the fiber orientation direction had higher tear strength than the parallel direction. This is thought to be because the effect of suppressing tearing was exhibited by the fine fibers oriented during tearing.

  The blending formulation and blending procedure of Comparative Example 3 were performed in the same manner as in Example 7. The modulus in the direction parallel to the fiber direction of the 100% elongation modulus in the fiber vertical direction was 6.2 MPa. The 100% elongation modulus in the fiber vertical direction was 3.9 MPa. The tensile strength was 10.5 MPa. All were low values compared with Examples 7-10.

  Regarding the tear strength of Comparative Example 3, the direction parallel to the fiber orientation direction was 43 N / mm, while the direction perpendicular to the fiber orientation direction was 48 N / mm. The tear strength was low compared to Examples 7 to 10 in both the direction perpendicular to and parallel to the fiber orientation direction. For this reason, sample 5 of the fiber reinforced thermoplastic resin composition used in Examples 7 to 10 uses silica of component (c), and the silanol of this silica is contained in the fiber reinforced thermoplastic resin composition. The chemical reaction with the component (a) LDPE, the component (b) EPDM, the component (d) nylon 6 and the like is considered to increase the crosslink density and improve the tear strength.

In Comparative Example 4, an elastic body was prepared in the same manner as in Example 7, except that the fiber reinforced thermoplastic resin composition was not used and the EPDM of the second elastomer was increased to 100 parts by weight. The modulus of 100% elongation of the tensile properties of the obtained elastic body was 2.8 MPa, which was a significantly lower value than Examples 7-10. The tensile strength was 11.5 MPa. All were low values compared with Examples 7-10.
The tear strength of Comparative Example 4 was 41 to 43 N / mm, which was a significantly lower value than Examples 7 to 10.

Further, as apparent from Table 3, the hardness of Examples 7 to 10 is 76 to 82, and a predetermined hardness can be obtained, so that the rigidity is also excellent.

Claims (11)

(A) polyolefin,
(B) a first elastomer,
(C) spherical silica having an average particle size of 1 μm or less and a water content of 1000 ppm or less,
(D) a thermoplastic resin having polyamide,
The component (a), the component (b), and the component (c) constitute a matrix, and the component (d) has an average diameter of 1 μm or less and an aspect ratio of 2 to 1000 in the matrix. (A) a fiber-reinforced thermoplastic resin composition that is dispersed as fibers, and each of the components (a), (b), (c), and (d) is chemically bonded;
(B) A fiber-reinforced elastic body obtained by kneading a second elastomer.   The total amount of the component (b) and the composition (B) is 100 parts by weight, the component (a) is 1 to 40 parts by weight, the component (c) is 1 to 50 parts by weight, and the component (d) is extremely fine. The fiber-reinforced elastic body according to claim 1, wherein 1 to 50 parts by weight of the fine fiber is used.   The fiber-reinforced elastic body according to claim 1, wherein at least one of the component (b) and the composition (B) is vulcanized.   In the composition (A), 80% or more of the component (d) is dispersed as ultrafine fibers in the matrix of the component (a), the component (b), and the component (c). The fiber reinforced elastic body as described in any one of 1-3.   The composition (A) has a silane coupling agent, and in the composition (A), the ultrafine fiber of the component (d) is at least of the component (a), the component (b), and the component (c). The fiber-reinforced elastic body according to any one of claims 1 to 4, wherein the fiber-reinforced elastic body is chemically bonded to any one of the components through at least one of a silane coupling agent and the component (c).   The fiber-reinforced elastic body according to any one of claims 1 to 5, wherein the melting point of the component (d) is 130 to 350 ° C.   The fiber-reinforced elastic body according to any one of claims 1 to 6, wherein the component (a) has a softening point of 50 ° C or higher or a melting point in the range of 70 to 250 ° C.   The fiber-reinforced elastic body according to any one of claims 1 to 7, wherein at least one of the component (b) and the composition (B) is a vulcanizable rubber.   The fiber-reinforced elastic body according to any one of claims 1 to 8, wherein at least one of the component (b) and the composition (B) is a thermoplastic elastomer. (A) polyolefin,
(B) a first elastomer,
(C) an average particle diameter of 1 μm or less and a water content of 1000 ppm or less of spherical silica and (d) a thermoplastic resin having a polyamide,
Component (a), component (b), and component (c) constitute a matrix, and component (d) is dispersed in the matrix as ultrafine fibers having an average diameter of 1 μm or less and an aspect ratio of 2 to 1000. And (A) a fiber reinforced thermoplastic resin composition in which each component of component (a), component (b), component (c) and component (d) is chemically bonded;
(B) A method for producing a fiber-reinforced elastic body, which comprises kneading a second elastomer. (A) polyolefin,
(B) a first elastomer,
(C) an average particle diameter of 1 μm or less and a water content of 1000 ppm or less of spherical silica and (d) a thermoplastic resin having a polyamide,
Component (a), component (b), and component (c) constitute a matrix, and component (d) is dispersed in the matrix as ultrafine fibers having an average diameter of 1 μm or less and an aspect ratio of 2 to 1000. And (A) a fiber reinforced thermoplastic resin composition in which each component of component (a), component (b), component (c) and component (d) is chemically bonded;
(B) a second elastomer;
(C) a vulcanizing agent;
A method for producing a fiber-reinforced elastic body comprising kneading and then heating.