JPH04325537A - Thermoplastic elastomer composition, molding and its production - Google Patents

Abstract

PURPOSE:To provide a thermoplastic elastomer molding, a crosslinked elastomer composition and a crosslinked elastomer molding having excellent tensile strength, elasticity and fuel oil resistance and practicable performances. CONSTITUTION:A thermoplastic elastomer molding made from 100 pts.wt. acrylic elastomer and at least 6 pts.wt. polyvinylidene fluoride, wherein the polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers or reticules. This molding is obtained by subjecting a mixture of the acrylic elastomer with the polyvinylidene fluoride resin or a molding thereof to a temperature higher than the melting point of the polyvinylidene fluoride resin during the period from the time when they are mixed to the time when the molding is withdrawn. A crosslinked thermoplastic elastomer composition in which the acrylic elastomer is crosslinked with a crosslinking agent, and the polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers or reticules and which has a content of diethylene glycol insolubles of 55% or above at 175 deg.C and its molding.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer molded product containing a mixture of an acrylic elastomer and a polyvinylidene fluoride resin, a crosslinked elastomer composition, a crosslinked elastomer molded product, and a method for producing the same.

0002

BACKGROUND OF THE INVENTION Recently, attempts have been made to impart the excellent properties of polyvinylidene fluoride resin to acrylic elastomer by mixing the acrylic elastomer and polyvinylidene fluoride resin. All of these are made by crosslinking a mixture of acrylic elastomer and polyvinylidene fluoride resin with a special crosslinking agent or organic peroxide that acts on the crosslinking monomer copolymerized into the acrylic elastomer to achieve the desired durability. In order to obtain a product with excellent properties, crosslinking the composition containing the acrylic elastomer and polyvinylidene fluoride resin is an essential condition. (JP-A-60-208312, JP-A-64-54050, JP-A-1-1520)
16, JP-A-1-152133, JP-A-1-152134)

0003

[Problems to be Solved by the Invention] However, since the composition of the acrylic elastomer and polyvinylidene fluoride resin of the above invention contains a crosslinking agent for crosslinking in advance, it cannot be used as a resin having a high softening temperature. When manufacturing laminates, bonding, coextrusion, etc., vulcanization reactions (hereinafter referred to as scorch) may occur in the composition during molding, making molding impossible. There was a problem in that it was often extremely difficult to select a crosslinking agent.

In order to solve these problems, the present inventors conducted research on mixtures of acrylic elastomers and polyvinylidene fluoride resins, and found that in mixtures of acrylic elastomers and polyvinylidene fluoride resins, If polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers, or networks, it is possible to simply mix the acrylic elastomer and polyvinylidene fluoride resin without vulcanizing and crosslinking the mixture. It is possible to obtain thermoplastic elastomer molded products, crosslinked elastomer compositions, and crosslinked elastomer molded products that have excellent tensile strength, elasticity, fuel oil resistance, etc., and can exhibit practical performance. The present invention has been completed.

[0005]

[Means for Solving the Problems] That is, the first invention of the present invention contains 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin, and the polyvinylidene fluoride resin is the same as the acrylic elastomer. Among these, it is a thermoplastic elastic molded product characterized by dispersion in the form of whiskers, fibers, or meshes.

The second invention is a method for producing a thermoplastic elastic molded product by molding a mixture obtained by mixing 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin. A thermoplastic elastic body characterized in that the mixture or the molded product is exposed to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin between the mixing of the acrylic elastomer and the polyvinylidene fluoride resin and the time of taking out the molded product. This is a method for manufacturing a molded article.

The third invention is an acrylic elastomer 1
00 parts by weight of polyvinylidene fluoride resin, 6 parts by weight or more of polyvinylidene fluoride resin, and a crosslinking agent. (Y) substantially decomposing the crosslinking agent of the mixture containing at least the acrylic elastomer and the crosslinking agent while simultaneously applying shearing to the mixture, or at least One of the steps of substantially decomposing the crosslinking agent while kneading the crosslinking agent into the system containing the acrylic elastomer is carried out in the order of (X) to (Y), and (Y) to ( This is a method for producing a thermoplastic crosslinked elastomer composition, characterized in that steps (X) and (Y) are carried out in this order or at the same time.

The fourth invention is an acrylic elastomer 1
00 parts by weight of polyvinylidene fluoride resin, 6 parts by weight or more of polyvinylidene fluoride resin, and a crosslinking agent. and (Y) simultaneously substantially decomposing the crosslinking agent of the mixture containing at least the acrylic elastomer and the crosslinking agent. a step of applying shear;
Alternatively, at least one of the steps of kneading the crosslinking agent into the system containing the acrylic elastomer and substantially decomposing the crosslinking agent at the same time is performed from step (X) to step (Y).
order of steps, (Y) step to (X) step order, or (X
This is a method for producing a thermoplastic crosslinked elastomer molded article, characterized in that step ) and step (Y) are carried out simultaneously.

The fifth invention is an acrylic elastomer 1
00 parts by weight, 6 parts by weight or more of polyvinylidene fluoride resin, and a crosslinking agent, the crosslinking agent being substantially decomposed,
Polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers, or networks.
This is a thermoplastic crosslinked elastomer composition characterized by having an insoluble content in diethylene glycol at 75°C of 55% or more.

[0010] The sixth invention is an acrylic elastomer 1
00 parts by weight, 6 parts by weight or more of polyvinylidene fluoride resin, and a crosslinking agent, the crosslinking agent being substantially decomposed,
Polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers, or networks.
This is a thermoplastic crosslinked elastic molded article characterized by having an insoluble content in diethylene glycol at 75°C of 55% or more.

The present invention will be explained in detail below. The present inventors have discovered that by simply mixing 6 parts by weight or more of polyvinylidene fluoride resin with 100 parts by weight of acrylic elastomer and leaving it at a specific temperature, a thermoplastic elastic molded product of acrylic elastomer can be obtained. Elastomer 10
For example, by kneading 6 parts by weight or more of polyvinylidene fluoride resin per 0 parts by weight in the presence of a crosslinking agent, the crosslinking agent is simultaneously decomposed to cause crosslinking in the acrylic elastomer, and then heated at a specific temperature. It has been found that a plastic crosslinked elastomer composition and a crosslinked elastomer molded article can be obtained.

The present invention utilizes the conventional vulcanization process, in which a crosslinking agent corresponding to the acrylic elastomer used as a raw material is added, and the acrylic elastomer is left to stand at a temperature at which the reaction of the crosslinking agent occurs rapidly. The present invention is characterized in that a molded article can be obtained by a molding method that does not require a vulcanization step to form crosslinks of a polyvinylidene fluoride resin composition. Therefore, the thermoplastic elastomer molded article, composition, and molded article of the present invention do not contain a crosslinking agent, or even if they contain a crosslinking agent, the crosslinking agent is substantially decomposed, and the molded article is molded during the molding process. There is no possibility of scorch occurring during the process, and it is possible to select a wide range of molding conditions that correspond to the performance of the desired product.

The thermoplastic elastic molded article of the present invention contains 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin, and the polyvinylidene fluoride resin has a whisker-like shape in the acrylic elastomer. , dispersed in the form of fibers or meshes.

FIG. 1 is a schematic diagram showing an example of a thermoplastic elastic molded article of the present invention. As shown in the figure, the thermoplastic elastic molded product of the present invention has polyvinylidene fluoride resin dispersed in an acrylic elastomer 1.
2 is a part where polyvinylidene fluoride resin is present in a high concentration, and 3 shows polyvinylidene fluoride resin extending from the part 2 in the form of whiskers, fibers, or networks, and as a whole, the polyvinylidene fluoride resin is present in the acrylic elastomer 1. It has a structure in which portions 2 of polyvinylidene fluoride resin present at a high concentration are dispersed through polyvinylidene fluoride resin 3 extending in the form of whiskers, fibers, or meshes.

The acrylic elastomer used in the present invention contains an acrylic acid alkyl ester and an acrylic acid alkoxyalkyl ester as main components, and a polymer containing a copolymerizable ethylenically unsaturated compound and a crosslinking monomer as other components. Indicates union.

Examples of acrylic acid alkyl esters include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-methylpentyl acrylate, n-octyl acrylate,
2-ethylhexyl acrylate, n-decyl acrylate, n-dodecyl acrylate, n-octadecyl acrylate, cyanomethyl acrylate, 1-cyanoethyl acrylate, 2-cyanoethyl acrylate, 1
-cyanopropyl acrylate, 2-cyanopropyl acrylate, 3-cyanopropyl acrylate, 4-cyanobutyl acrylate, 6-cyanohexyl acrylate, 2-ethyl-6-cyanohexyl acrylate,
Examples include 8-cyanooctyl acrylate.

Examples of acrylic acid alkoxyalkyl esters include 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-(n-propoxy)ethyl acrylate, 2-(n-butoxy)ethyl acrylate, and 3-methoxypropyl acrylate. , 3-ethoxypropyl acrylate, 2-(n-propoxy)propyl acrylate, 2-(n-butoxy)propyl acrylate, and the like.

[0018] As the copolymerizable ethylenically unsaturated compound, various compounds can be used as required, examples include acrylic acid, methacrylic acid, crotonic acid, 2-pentenoic acid, maleic acid. , carboxyl group-containing compounds such as fumaric acid and itaconic acid, 1,1-dihydroperfluoroethyl (meth)acrylate, 1,
1-dihydroperfluoropropyl (meth)acrylate, 1,1,5-trihydroperfluorohexyl (meth)acrylate, 1,1,2,2-tetrahydroperfluoropropyl (meth)acrylate, 1,1,7-
Fluorine-containing acrylic acid esters such as trihydroperfluoroheptyl (meth)acrylate, 1,1-dihydroperfluorooctyl (meth)acrylate, and 1,1-dihydroperfluorodecyl (meth)acrylate, 1
- Hydroxyl group-containing compounds such as hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and hydroxyethyl (meth)acrylate; tertiary amino groups such as diethylaminoethyl (meth)acrylate and dibutylaminoethyl (meth)acrylate; Containing monomers, methacrylates such as methyl methacrylate, octyl methacrylate, alkyl vinyl ketones such as methyl vinyl ketone, vinyl and allyl ethers such as vinyl ethyl ether, allyl methyl ether,
Vinyl aromatic compounds such as styrene, α-methylstyrene, chlorostyrene, vinyltoluene, vinyl nitriles such as acrylonitrile and methacrylonitrile, ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, vinyl acetate, propion Examples include vinyl acid, alkyl fumarate, and the like.

Examples of crosslinking monomers include diene compounds, dihydrodicyclopentadienyl group-containing (meth)
Examples include acrylic esters, epoxy group-containing ethylenically unsaturated compounds, active halogen-containing ethylenically unsaturated compounds, carboxyl group-containing ethylenically unsaturated compounds, and active hydrogen group-containing ethylenically unsaturated compounds. Butadiene, isoprene, ethylidene norbornene, dicyclopentadiene, dihydrodicyclopentadiene (meth)acrylate, allyl glycidiether, glycidyl methacrylate, glycidyl acrylate, 2-chloroethyl vinyl ether, 2-chloroethyl acrylate, 2-chloroethyl Acrylate, 2-chloroethyl methacrylate, vinyl chloroacetate, acrylic acid, methacrylic acid, maleic acid,
Examples include fumaric acid, monomethyl ester of maleic acid, monomethyl ester of fumaric acid, N-methylol acrylamide, and allyl cyanoacetate.

Acrylic elastomers used for the purpose of obtaining high fuel oil resistance by mixing with polyvinylidene fluoride resins include 0 to 15% by weight of ethylene, 0 to 40% by weight of vinyl carboxylate, and 0 to 20% by weight of acrylonitrile. It is obtained by polymerizing 60 to 100% by weight of alkoxyalkyl acrylate. A preferred acrylic elastomer is alkoxylalkyl acrylate 80
~100% by weight, 0 to 20% by weight of acrylonitrile, 0 to 5% by weight of ethylene, and 0 to 5% by weight of fatty acid vinyl. A more preferable acrylic elastomer is an alkoxyalkyl acrylate of 80 to 10
0% by weight and 0 to 20% by weight of acrylonitrile, and a particularly preferred acrylic elastomer is 85 to 95% by weight of alkoxyalkyl acrylate.
and 5 to 15% by weight of acrylonitrile.

The polyvinylidene fluoride resin used in the present invention refers to polyvinylidene fluoride and a copolymer of vinylidene fluoride and other copolymerizable monomers. Other copolymer monomers include, for example, hexafluoropropylene,
Pentafluoropropylene, trifluoroethylene, trifluorochloroethylene, tetrafluoroethylene vinyl fluoride, perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), other olefins, acrylic esters, etc., and one of these or Two or more types are used for copolymerization.

The amount of polyvinylidene fluoride resin mixed with the acrylic elastomer is 1 part of the acrylic elastomer.
00 parts by weight or more, preferably 20 parts by weight or more, more preferably 30 to 80 parts by weight,
If it is less than 6 parts by weight, the presence of whisker-like, fibrous, or mesh-like networks of the polyvinylidene fluoride resin in the acrylic elastomer will not be sufficient, and the networks of the polyvinylidene fluoride resin will not be sufficiently interconnected, so that the tensile strength of the mixture will be reduced. Strength does not reach practical strength. Further, a mixture containing 30 parts by weight or more of polyvinylidene fluoride resin provides good tensile strength. In terms of developing tensile strength, there is no upper limit for the content of polyvinylidene fluoride resin, but as the amount of polyvinylidene fluoride resin mixed increases, the hardness of the molded product increases, and the cost of the mixture also increases, so elastomer Its uses are becoming increasingly limited.

The method for producing the thermoplastic elastic molded product of the present invention described above is produced by molding a mixture obtained by mixing 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin. However, it is necessary to expose the mixture or the molded product to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin between the time the acrylic elastomer and the polyvinylidene fluoride resin are mixed until the molded product is taken out. By exposing this mixture or molded product to a temperature higher than the melting point of the polyvinylidene fluoride resin, the polyvinylidene fluoride resin is dissolved in the acrylic elastomer.
Whisker-like, fibrous, or mesh-like dispersed structures are formed.

The method of mixing the acrylic elastomer and polyvinylidene fluoride resin is usually the method of mixing rubber and thermoplastic resin, that is, the open roll method used in the rubber industry and when preparing thermoplastic resin compounds. A closed mixer such as a Banbury mixer or an extruder type mixer such as a co-kneader can be used.

Specific examples of methods for obtaining molded products by exposing a mixture obtained by mixing an acrylic elastomer and a polyvinylidene fluoride resin or a molded product thereof to a temperature higher than the melting point of the polyvinylidene fluoride resin include: A method in which the two are mixed and then molded at a temperature higher than the melting point of the vinylidene resin; ■ A method in which a mixture of both is molded at a temperature higher than the melting point of the polyvinylidene fluoride resin; ■ A method in which both are molded at a temperature lower than the melting point of the polyvinylidene fluoride resin. and then molding the mixture after bathing it in a temperature higher than the melting point of the polyvinylidene fluoride resin; (1) mixing both at a temperature lower than the melting point of the polyvinylidene fluoride resin;
A method such as molding at a temperature lower than the melting point of the polyvinylidene fluoride resin and then exposing the molded product to a temperature higher than the melting point of the polyvinylidene fluoride resin can be used.

The form of the polyvinylidene fluoride resin used in the present invention is not particularly limited, but for example, powder, granules, granules, blocks, plates, or sheets can be used. can.

When the polyvinylidene fluoride resin is a powder, the polyvinylidene fluoride resin powder is kneaded into the acrylic elastomer at a temperature lower than the melting point of the polyvinylidene fluoride resin, and the polyvinylidene fluoride resin is mixed into the acrylic elastomer in advance. It is also effective to obtain a mixture by mechanically dispersing resin powder in a solid state, and then heating the mixture to a temperature higher than the melting point of the polyvinylidene fluoride resin and continuing kneading. This method is excellent in that the polyvinylidene fluoride resin can be mechanically and uniformly dispersed in the acrylic elastomer in advance.

Furthermore, after kneading polyvinylidene fluoride resin powder into an acrylic elastomer at a temperature lower than the melting point of the polyvinylidene fluoride resin, sheeting it as it is at a temperature below the melting point of the polyvinylidene fluoride resin and molding it again, It is also effective to include a step of heating the polyvinylidene fluoride resin to a temperature higher than its melting point during the molding process.

Next, the thermoplastic crosslinked elastomer composition of the present invention, which may contain a crosslinking agent for crosslinking the acrylic elastomer, will be described. The thermoplastic crosslinked elastomer composition contains 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, and the crosslinking agent is substantially decomposed, and the polyvinylidene fluoride resin is It is dispersed in the form of whiskers, fibers, or networks in the elastomer, and its insoluble content in diethylene glycol at 175°C is 55% or more.

When a crosslinking agent for an acrylic elastomer is used to prepare the thermoplastic crosslinked elastomer composition of the present invention, the crosslinking agent is a crosslinking agent corresponding to the crosslinking monomer copolymerized with the acrylic elastomer. It is common to use agents. In the case of an acrylic elastomer in which a crosslinkable monomer is not copolymerized, an organic peroxide is used, and a polyfunctional monomer and other additives can also be used in combination with this.

When the crosslinking monomer is a diene compound or a dihydrodicyclopentadienyl group-containing (meth)acrylic ester, organic peroxides and vulcanizing agents used for natural rubber, etc. are generally used as the crosslinking agent. used. Also,
When the crosslinking monomer is an epoxy group-containing ethylenic compound, in addition to the curing agent used for epoxy resins, organic carboxylic acid ammonium, dithiocarbamate, quaternary ammonium salt, guanidine, sulfur compound, alkaline earth metal hydroxide Lead oxide, zinc oxide, lead oxide, and zinc oxide can be used. In addition, when the crosslinking monomer is an active halogen-containing ethylenic compound, organic ammonium carboxylate,
Combinations of organic carboxylic acid alkali metal salts and sulfur compounds can be used. When the crosslinkable monomer is an ethylenically unsaturated compound containing a carboxyl group, an organic amine compound such as a guanidine compound can be used.

[0032] When using an organic peroxide as a crosslinking agent,
As the organic peroxide, those commonly used for crosslinking rubber can be used, and examples thereof include di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, α,α-bis (t-butylperoxyisopropyl)benzene, 2,5-dimethyl 2,5-di(t-butylperoxy)hexane, 2,5
-dimethyl-2,5-di(t-butylperoxyhexyne-3,1,1-bis(t-butylperoxy)-3,
3,5-trimethylcyclohexane, n-butyl-4,
4-bis(t-butylperoxy)valerate, 2,2
-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, and the like.

Although the amount of the crosslinking agent is not limited, it is usually used in an amount of about 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight, per 100 parts by weight of the acrylic elastomer. If it is less than 0.1 part by weight, the effect of addition is often small, and if it exceeds 10 parts by weight, the fluidity of the resulting composition may be impaired.

[0034] When using peroxide, it is more effective to use it together with a polyfunctional monomer, and the appropriate amount is 0.5 parts by weight or less per 100 parts by weight of the acrylic elastomer. It is. If the amount exceeds 0.5 part by weight, the fluidity of the resulting composition may be impaired.

As the polyfunctional monomer, trimethylolpropane trimethacrylate and trimethylolpropane triacrylate are the most effective, including triallyl isocyanurate, triallyl cyanurate, triallyl trimellitate, and trimethylolpropane triacrylate. ,
1,6-hexanediol acrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, diallyl phthalate, 1,2-polybutadiene, etc. are also applicable.

Further, when crosslinking using a peroxide, it may be effective to use a radical scavenger or a thiourea derivative in combination in order to balance the physical properties of the crosslinked product. It is desirable to use 3 parts by weight or less of the radical scavenger and 5 parts by weight or less of the thiourea derivative based on 100 parts by weight of the acrylic elastomer. If a large amount of radical scavenger is used, peroxide is consumed and the purpose of balancing the physical properties of the crosslinked product is lost. If a large amount of a thiourea derivative is used, it will have the opposite effect of deteriorating the physical properties of the crosslinked product. It is desirable to use them alone or in combination within the above range.

As the radical scavenger, compounds generally used as polymerization inhibitors or anti-aging agents, sulfur or sulfur-containing compounds are used, and typical examples include phenothiazine and 2-6-di-t-butyl-p-cresol. and sulfur compounds such as rubber vulcanization accelerators.

In addition, various fillers, plasticizers, processing aids or stabilizers commonly used in the rubber industry can be added to suit the application of the mixture. It is also possible to mix nitrile rubber, hydrogenated nitrile rubber, epichlorohydrin rubber, ethylene propylene rubber, butyl rubber, fluororubber, etc., if necessary.

When the filler is used in an amount of 5 to 300 parts by weight based on 100 parts by weight of the acrylic elastomer, the mixing state and processability are improved and more effective mixing becomes possible. If it is less than 5 parts by weight, the effect is often low;
If the amount exceeds the weight part, processability may be impaired.

The plasticizer may be one that does not impair the purpose of the present invention and has an affinity for the composition, such as α-
Examples include olefin oligomers, polybutenes, polyethers, and polyesters. Furthermore, if desired, it is also possible to mix it with other rubbers, such as various other rubbers with excellent fuel oil resistance.

[0041] The method for producing the thermoplastic crosslinked elastomer composition of the present invention described above is based on
From a raw material system containing 00 parts by weight of polyvinylidene fluoride resin, 6 parts by weight or more of polyvinylidene fluoride resin, and a crosslinking agent, (X) a mixture containing at least an acrylic elastomer and polyvinylidene fluoride resin is heated to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin. and (Y) substantially decomposing the crosslinking agent of the mixture containing at least the acrylic elastomer and simultaneously applying shear, or while kneading the crosslinking agent into the system containing at least the acrylic elastomer. At the same time, one of the steps of substantially decomposing the crosslinking agent is carried out in the order of (X) to (Y);
) process to (X) process, or (X) process and (Y)
Manufactured by a method in which the steps are performed simultaneously.

In the above step (X), mixing the acrylic elastomer and polyvinylidene fluoride resin includes:
The equipment used for kneading the above-mentioned rubber and thermoplastic resin is usually used, and in step (X), the mixture obtained by mixing the above-mentioned acrylic elastomer and polyvinylidene fluoride resin is heated to a temperature above the melting point of the polyvinylidene fluoride resin. A method similar to the method of bathing at a temperature of 1 can be used.

The above step (Y) is a step of substantially decomposing the crosslinking agent of the mixture containing at least an acrylic elastomer and a crosslinking agent while simultaneously applying shear (Y-1).
(Step Y-2) or a step of substantially decomposing the crosslinking agent while kneading the crosslinking agent into a system containing at least an acrylic elastomer (Step Y-2).

[0044] As a specific method for the Y-1 step, a mixture of an acrylic elastomer containing a crosslinking agent and a polyvinylidene fluoride resin is placed in a closed mixer, and the crosslinking agent is decomposed while applying mechanical shear. An example of this method is to raise the temperature to substantially decompose the crosslinking agent to obtain a composition containing 55% or more of insoluble matter in diethylene glycol at 175° C. in the mixture.

[0045] As a specific method for the Y-2 step, the acrylic elastomer is put into a closed mixer, heated to the decomposition temperature of the crosslinking agent while applying shear, and then the crosslinking agent is added and kneaded until the material is completely mixed. A method for obtaining a composition containing 55% or more of insoluble matter in diethylene glycol at 175° C. can be mentioned by temporarily decomposing the crosslinking agent and then kneading another crosslinking agent.

Next, the thermoplastic crosslinked elastic molded article of the present invention contains 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, and the crosslinking agent is substantially decomposed. The polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers, or networks, and the insoluble content in diethylene glycol at 175°C is 55% or more.

The method for producing a thermoplastic crosslinked elastomer molded article of the present invention includes a method for producing a molded article from the above thermoplastic crosslinked elastomer composition, or the above steps (X) to (Y). In this method, a molded article is manufactured by performing the steps (Y) to (X) in this order, or the (X) and (Y) steps simultaneously.

The thermoplastic crosslinked elastomer composition and crosslinked elastic molded article of the present invention are obtained by dispersing polyvinylidene fluoride resin in an acrylic elastomer in the form of whiskers, fibers, or networks. Moreover, since the acrylic elastomer has a structure in which the acrylic elastomer is crosslinked with a crosslinking agent and the crosslinking agent is substantially decomposed, the molded product has good physical properties such as compression set.

Further, it is desirable that the thermoplastic crosslinked elastomer composition and crosslinked elastomer molded product of the present invention have an insoluble content in diethylene glycol of 55% or more, preferably 55% to 70% at 175°C. minutes is 55
%, it is difficult to obtain excellent compression set. Also, 7
If it exceeds 0%, compression set is good, but moldability tends to decrease.

Further, the thermoplastic crosslinked elastomer composition and the crosslinked elastomer molded article of the present invention have a volume change (Δ
V) is preferably in the range of 50 to 250%, preferably 100 to 200%; if it is less than 50%, moldability is poor;
If it exceeds 250%, it is difficult to obtain excellent compression set.

The thermoplastic elastomer molded product, crosslinked elastomer composition, and crosslinked elastomer molded product of the present invention are useful as materials suitable for producing various engineering products, such as diaphragms, packings, and gaskets. , hoses, tubes, etc.

[0052]

[Examples] The present invention will be specifically explained below with reference to Examples. Examples 1 to 7 and Comparative Examples 1 to 3 Using acrylic elastomer A and polyvinylidene fluoride resin, according to the formulation and molding method shown in Table 1,
The thermoplastic elastomer composition was molded, and the physical properties of the molded product were measured. The results are shown in Table 1. Acrylic elastomer A, polyvinylidene fluoride resin, molding method, and test method are shown at the end.

From the results in Table 1, it can be seen that by mixing 6 parts by weight or more of polyvinylidene fluoride resin with 100 parts by weight of the acrylic elastomer, practical strength can be developed without going through the conventional vulcanization process.

Examples 8 to 13 and Comparative Examples 4 to 5 Using acrylic elastomer B and polyvinylidene fluoride resin, thermoplastic elastomer compositions were molded according to the formulation and molding method shown in Table 2. Physical properties were measured. The results are shown in Table 2. Acrylic elastomer B
, polyvinylidene fluoride resin, molding method, and test method are shown at the end.

From the results in Table 1, it can be seen that by mixing 6 parts by weight or more of polyvinylidene fluoride resin with 100 parts by weight of the acrylic elastomer, practical strength can be developed without going through the conventional vulcanization process. In addition, a thermoplastic elastomer composition (Example 10) obtained by kneading a crosslinking agent for a normal acrylic elastomer in advance and decomposing it during mixing of the acrylic elastomer and polyvinylidene fluoride resin also shows sufficient performance. It is recognized that

(1)-1 Acrylic elastomer A
Dissolve 2120 g of polyvinyl alcohol and 86 g of sodium acetate in a 130 liter autoclave to make 65
Pour in the aqueous solution adjusted so that the amount of the autoclave is 1.5 g, and while stirring, add 8.6 kg of vinyl acetate and 34.6 kg of 2-methoxyethyl acrylate to emulsify it. After purging the inside of the autoclave with nitrogen gas, ethylene monomer is forced into the autoclave from the top. did. Ethylene pressure is 45Kg/cm2 at polymerization temperature of 55℃
I adjusted it so that A polymerization initiator aqueous solution was separately added several times through an injection port, and the polymerization was stopped in about 10 hours.
The monomer was removed, coagulated with a 3% borax aqueous solution, dehydrated, and the dehydrated and dried polymer was made into acrylic elastomer A.
And so.

(1)-2 Acrylic elastomer B
Production: 43 kg of water, 4 kg of acrylonitrile, 36 kg of methoxyethyl acrylate in a 130 liter autoclave.
, 700 g each of Denka Poval B-05 and B-17 as polyvinyl alcohol, 60 g of sodium acetate, 2 g of ferric sulfate, 4 g of ethylenediaminetetraacetic acid, and 90 g of a cocatalyst were added and mixed with stirring, and the internal temperature of the autoclave was set to 45°C. . The air above the autoclave was replaced with nitrogen.

Separately, an aqueous polymerization initiator solution was injected through an injection port to allow polymerization to proceed, and the injection was completed in 12 hours. An aqueous solution of Glauber's salt was added to the produced polymer emulsion to solidify the polymer, which was washed with water, dehydrated and dried to obtain an acrylic elastomer B.

(2) Polyvinylidene fluoride resin As shown in Table 1, a polyvinylidene fluoride powder product KYNAR741 (melting point (165 to 170°C) manufactured by Pennwalt Co., Ltd.) was used.

(3) Molding method (molding method A) The acrylic elastomer is heated to a surface temperature of 40
The mixture was wound around a roll at 0.degree. C., and after kneading finely powdered polyvinylidene fluoride resin, a filler was further kneaded. The resulting mixture was wound around a roll having a surface temperature of 170° C. for 5 minutes, turned 3/4 once per minute on the left and right, sheeted, and cooled at room temperature. The obtained sheet was pressed using a press molding machine at 170°C for 10 minutes. Further, the molded product was cooled with water for 10 minutes while being kept under pressure. (Molding method B) Molding was carried out without performing the operation using rolls with a surface temperature of 170° C. in molding method A. (Molding method C) Molding was carried out under the press molding temperature condition of 150°C in molding method A. (Molding method D) After kneading polyvinylidene fluoride resin powder into an acrylic elastomer with a crosslinking agent and other fillers at a surface temperature of 40°C using an 8-inch roll, heat treatment and I did the molding.

(4) Physical properties After being molded and left at room temperature for one day, JIS K6
301, various physical properties were measured.

Fuel oil resistance: Fuel C (isooctane/toluene: 50/50% by volume) and Fuel C
/Ethanol: 80/20% by volume mixed solution (E-20)
The volume change (ΔV) after immersion at 40° C. for 70 hours was determined.

Diethylene glycol insoluble matter: After immersing in diethylene glycol at 175°C for 22 hours, 200°C
It was dried in a gear oven for 70 hours, its weight was measured, and the insoluble content was determined using the following formula (I).

[0064]

[Math 1]

However, W = 100 + 175°C Part of the formulation dissolved in diethylene glycol Resistance to diethylene glycol: The volume change (ΔV) after immersion in diethylene glycol at 175°C for 22 hours was measured and determined by the following formula (II).

[0066]

[Math 2]

However, V1 = weight in air before immersion - weight in water before immersion V2 = weight in air after immersion - weight in water after immersion

006
8] (5)-1 Observation of the mixed state A thin section of the mixture was prepared using a microtome, and the degree of development of the polyvinylidene fluoride resin network in the acrylic elastomer was observed using an electron microscope. The evaluation is as follows.

◎: Large amount of mesh development is observed ○
: Those with mesh development observed △: Those with some mesh development observed ×: Those with no mesh development observed

(5)-2 Morphology of thermoplastic molded product Figure 2 is an electron micrograph (magnification: 15 ,000 times), and compositions corresponding to Example 3, Example 4, and Comparative Example 3 in FIGS. 3 to 5, respectively,
In order to make the presence of polyvinylidene fluoride resin easier to understand, a similar electron micrograph showing the particle structure of polyvinylidene fluoride resin in a molded product without carbon black is shown.

[0071]

[Table 1]

[0072]

[Table 2]

(Note) 3) Product name: “Perhexa V-40” manufactured by NOF Corporation (contains 40% by weight of N-butyl-4,4-bis(t-butylperoxy)valerate)

[0074]

As explained above, in the thermoplastic elastic molded article of the present invention, in a mixture of an acrylic elastomer and a polyvinylidene fluoride resin, the polyvinylidene fluoride resin has a whisker-like shape in the acrylic elastomer. Because they are dispersed in the form of fibers or networks, you can simply mix acrylic elastomer and polyvinylidene fluoride resin without vulcanizing and crosslinking the mixture, and it has excellent tensile strength, elasticity, and fuel oil resistance. Effects with practical performance can be obtained.

In addition, in the crosslinked elastomer composition and crosslinked elastomer molded product of the present invention, an acrylic elastomer is crosslinked with a crosslinking agent, and in the acrylic elastomer, polyvinylidene fluoride resin has a whisker-like or fibrous shape. Or, since it is dispersed in a network, it not only improves the compression set due to crosslinking, but also has excellent tensile strength, elasticity, fuel oil resistance, etc., and has practical performance effects.

Furthermore, according to the manufacturing method of the present invention, the thermoplastic elastomer molded article, the crosslinked elastomer composition, and the crosslinked elastomer molded material, which have practical performance even without the conventional vulcanization process, can be produced. You can get things easily.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of a thermoplastic elastic molded article of the present invention.

[Fig. 2] Electron micrograph showing the particle structure of polyvinylidene fluoride resin in the molded product of Example 3 (magnification: 15,
000 times).

FIG. 3: Electron micrograph showing the particle structure of polyvinylidene fluoride resin in a molded product with a composition corresponding to Example 3 but excluding carbon black (magnification: 15,000x)
It is.

FIG. 4: Electron micrograph showing the particle structure of polyvinylidene fluoride resin in a molded product with a composition corresponding to Example 4 but excluding carbon black (magnification: 15,000 times)
It is.

FIG. 5: Electron micrograph showing the particle structure of polyvinylidene fluoride resin in a molded product with a composition corresponding to Comparative Example 3 but excluding carbon black (magnification: 15,000 times)
It is.

[Explanation of symbols]

1 Acrylic elastomer 2 Portion where polyvinylidene fluoride resin is present in high concentration 3 Polyvinylidene fluoride resin extending in the form of whiskers, fibers, or networks

Claims (6)

[Claims] Claim 1: Contains 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin, wherein the polyvinylidene fluoride resin is dispersed in the acrylic elastomer in the form of whiskers, fibers, or networks. A thermoplastic elastic molded article characterized by: 2. A method for producing a thermoplastic elastic molded article by molding a mixture obtained by mixing 100 parts by weight of an acrylic elastomer and 6 parts by weight or more of a polyvinylidene fluoride resin, the method comprising: From mixing the polyvinylidene fluoride resin to taking out the molded product,
A method for producing a thermoplastic elastic molded article, which comprises exposing the mixture or molded article to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin. 3. A method for producing a thermoplastic elastomer composition from a raw material system containing 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, the method comprising: (X) at least an acrylic elastomer; A step of exposing a mixture containing an elastomer and a polyvinylidene fluoride resin to a temperature higher than the melting point of the polyvinylidene fluoride resin, and (Y) substantially decomposing the crosslinking agent of the mixture containing at least an acrylic elastomer and a crosslinking agent. Either a step of simultaneously applying shear, or a step of substantially decomposing the crosslinking agent while simultaneously kneading the crosslinking agent into a system containing at least an acrylic elastomer,
(X) process to (Y) process, (Y) process to (X)
A method for producing a thermoplastic crosslinked elastomer composition, characterized in that the steps are performed in order or the steps (X) and (Y) are performed simultaneously. 4. A method for producing a thermoplastic elastomer molded article by molding a mixture obtained from a raw material system containing 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, the method comprising: , (X) a step of exposing a mixture containing at least an acrylic elastomer and a polyvinylidene fluoride resin to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin, and (Y) a crosslinking agent for the mixture containing at least an acrylic elastomer and a crosslinking agent. (X) From process to (Y) process order,
(Y) process to (X) process, or (X) process and (
Y) A method for producing a thermoplastic crosslinked elastomer molded article, characterized in that the steps are carried out simultaneously. 5. Contains 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, the crosslinking agent being substantially decomposed, and the polyvinylidene fluoride resin being contained in the acrylic elastomer. , a thermoplastic crosslinked elastomer composition characterized in that it is dispersed in the form of whiskers, fibers, or networks, and has an insoluble content in diethylene glycol of 55% or more at 175°C. 6. Contains 100 parts by weight of an acrylic elastomer, 6 parts by weight or more of a polyvinylidene fluoride resin, and a crosslinking agent, the crosslinking agent being substantially decomposed, and the polyvinylidene fluoride resin being contained in the acrylic elastomer. A thermoplastic crosslinked elastic molded article, which is dispersed in the form of whiskers, fibers, or networks, and has an insoluble content in diethylene glycol of 55% or more at 175°C.