JP2000159901A - Production of elastic body formed article having thermoplastic property, crosslinked elastic body composition and crosslinked elastic body formed article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for manufacturing an elastic body formed article having thermoplastic property excellent in tensile strength, elasticity and fuel oil resistance, and having a practical performance. SOLUTION: A process for manufacturing an elastic body formed article having thermoplastic property by molding a mixture obtained by mixing 100 pts.wt. of an acrylic elastomer and 6 pts.wt. or more of a polyvinylidene fluoride resin, and taking it out as a formed article. In this process, at any point from mixing of the acrylic elastomer and the polyvinylidene fluoride resin to taking out of the formed article, the mixture or the formed article is exposed to a temperature above the melting point of the polyvinylidene fluoride resin. In the obtained elastic body formed article, the polyvinylidene fluoride resin is dispersed in a hair shape, fabric shape or net shape in the acrylic elastomer.

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 article in which an acrylic elastomer and a polyvinylidene fluoride resin are mixed, a crosslinked elastic composition, and a method for producing a crosslinked elastomer molded article.

[0002]

2. Description of the Related Art Recently, an acrylic elastomer is mixed with a polyvinylidene fluoride resin to impart excellent properties of the polyvinylidene fluoride resin to the acrylic elastomer. In each case, the desired durability is achieved by crosslinking a mixture of an acrylic elastomer and a polyvinylidene fluoride resin with a special crosslinking agent or an organic peroxide that acts on a crosslinking monomer copolymerized with the acrylic elastomer. A product having excellent properties is obtained, and it is an essential condition to crosslink a composition containing an acrylic elastomer and a polyvinylidene fluoride resin. (JP-A-60-208312, JP-A-64-54050, JP-A-1-152
016, JP-A-1-152133, JP-A-1-152134)

[0003]

However, the composition of the acrylic elastomer and the polyvinylidene fluoride resin of the invention described above contains a resin having a high softening temperature because a crosslinking agent for crosslinking is mixed in advance. When manufacturing, laminating, co-extruding products, etc., a vulcanization reaction (hereinafter referred to as scorch) may occur in the composition during molding, and molding may be impossible. In addition, there is a problem that the selection of a crosslinking agent is often extremely difficult.

The present inventors have conducted research on a mixture of an acrylic elastomer and a polyvinylidene fluoride resin in order to solve such a problem. As a result, in a mixture of an acrylic elastomer and a polyvinylidene fluoride resin, When the polyvinylidene fluoride resin is dispersed in the form of whiskers, fibers or meshes in the acrylic elastomer, the mixture can be vulcanized and not cross-linked, just mixing the acrylic elastomer and the polyvinylidene fluoride resin. Therefore, it is possible to obtain a thermoplastic elastic molded article, a crosslinked elastic composition, and a crosslinked elastic molded article which are excellent in tensile strength, elasticity, fuel oil resistance, etc. and can exhibit practical performance. Heading, the present invention has been completed.

[0005]

That is, the first invention of the present invention is to form 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 to form a thermoplastic elastomer. A method for producing a molded article, comprising mixing the acrylic elastomer and polyvinylidene fluoride resin until the molded article is formed, or after molding to give a molded article, and then mixing the mixture or the molded article with polyvinylidene fluoride. This is a method for producing a thermoplastic elastic molded article, characterized in that the resin is bathed at a temperature not lower than the melting point of the resin.

A second invention is a method for producing a thermoplastic elastic 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, (X) a step of bathing a mixture containing at least the acrylic elastomer and the polyvinylidene fluoride resin at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin; and (Y) a crosslinking agent of the mixture containing at least the acrylic elastomer and the crosslinking agent. (X) a step of simultaneously applying shear while substantially decomposing, or a step of substantially decomposing the crosslinking agent while kneading the crosslinking agent into a system containing at least the acrylic elastomer, To (Y) process order,
A method for producing a thermoplastic crosslinked elastic composition, wherein the steps (Y) to (X) are performed in order, or the steps (X) and (Y) are simultaneously performed.

In a third aspect of the present invention, a thermoplastic elastomer molded article is formed by molding a mixture obtained from a raw material system containing 100 parts by weight of an acrylic elastomer, at least 6 parts by weight of a polyvinylidene fluoride resin and a crosslinking agent. A method of manufacturing,
(X) a step of bathing a mixture containing at least the acrylic elastomer and the polyvinylidene fluoride resin at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin; and (Y) a crosslinking agent of the mixture containing at least the acrylic elastomer and the crosslinking agent. (X) a step of simultaneously applying shear while substantially decomposing, or a step of substantially decomposing the crosslinking agent while kneading the crosslinking agent into a system containing at least the acrylic elastomer, From step (Y) to step (Y), step (Y) to step (X), or step (X) and step (Y) at the same time. is there.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The present inventors can obtain a thermoplastic elastomer molded article of an acrylic elastomer simply by mixing at least 6 parts by weight of a polyvinylidene fluoride resin with 100 parts by weight of an acrylic elastomer and keeping the mixture at a specific temperature. 6 parts by weight or more of polyvinylidene fluoride resin with respect to 100 parts by weight of the elastomer, for example, in the presence of a crosslinking agent, kneading while simultaneously decomposing the crosslinking agent to cause crosslinking of the acrylic elastomer, and by maintaining a specific temperature. It has been found that a thermoplastic crosslinked elastic material composition and a crosslinked elastic material molded product can be obtained.

In the present invention, a so-called vulcanization step, that is, a crosslinking agent corresponding to an acrylic elastomer used as a raw material is added, and the mixture is allowed to stand at a temperature at which the reaction of the crosslinking agent is promptly carried out. It is characterized in that a molded product can be obtained by a molding method that does not require a vulcanization step of forming a crosslink of the polyvinylidene fluoride resin composition. Therefore, the thermoplastic elastic molded article, the crosslinked elastic composition and the crosslinked elastic molded article obtained by the present invention do not contain a crosslinking agent, or the crosslinking agent is substantially contained even if the crosslinking agent is contained. Since there is no possibility of generating scorch during the molding process in the molding process, it is possible to select a wide range of molding conditions corresponding to the performance of the target product.

The thermoplastic elastomer molded article produced according to 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 contained in the acrylic elastomer. , Whiskers, fibers or meshes.

FIG. 1 is a schematic explanatory view showing an example of a molded thermoplastic elastic body produced according to the present invention. As shown in the figure, the thermoplastic elastomer molded article produced according to the present invention has an acrylic elastomer 1 in which polyvinylidene fluoride resin is dispersed, and 2 shows a high concentration of polyvinylidene fluoride resin. Reference numeral 3 denotes a polyvinylidene fluoride resin extending in a whisker-like, fibrous, or mesh-like form from the second part, and extends in the acrylic elastomer 1 as a whole in a whisker-like, fibrous, or mesh-like form. It has a structure in which the polyvinylidene fluoride resin 2 is present at a high concentration with the polyvinylidene fluoride resin 3 serving as an intermediary.

[0012] The acrylic elastomer used in the present invention is a polymer containing an alkyl acrylate or an alkoxyalkyl acrylate as a main component, and a copolymerizable ethylenically unsaturated compound and a crosslinkable monomer as other components. Indicates merging.

Examples of the alkyl acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-methylpentyl acrylate, and the like. 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, 8-cyanooctyl acrylate, and the like.

Examples of the alkoxyalkyl acrylate 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.

As the copolymerizable ethylenically unsaturated compound, various compounds can be used, if necessary. Examples thereof include acrylic acid, methacrylic acid, crotonic acid, 2-pentenoic acid, and maleic acid. , Fumaric acid, itaconic acid, and other carboxyl group-containing compounds, 1,1-dihydroperfluoroethyl (meth) acrylate,
1-dihydroperfluoropropyl (meth) acrylate, 1,1,5-trihydroperfluorohexyl (meth) acrylate, 1,1,2,2-tetrahydroperfluoropropyl (meth) acrylate, 1,1,7-
Fluorinated acrylates such as trihydroperfluoroheptyl (meth) acrylate, 1,1-dihydroperfluorooctyl (meth) acrylate, 1,1-dihydroperfluorodecyl (meth) acrylate;
Hydroxyl-containing compounds such as 1-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and hydroxyethyl (meth) acrylate; tertiary aminos such as diethylaminoethyl (meth) acrylate and dibutylaminoethyl (meth) acrylate Group-containing monomer, methyl methacrylate, methacrylate such as octyl methacrylate, alkyl vinyl ketone such as methyl vinyl ketone, vinyl ethyl ether, vinyl and allyl ether such as allyl methyl ether, styrene, α-methylstyrene, chlorostyrene,
Vinyl aromatic compounds such as vinyl toluene, vinyl nitriles such as acrylonitrile and methacrylonitrile,
Ethylene, propylene, vinyl chloride, vinylidene chloride,
Examples include vinyl fluoride, vinylidene fluoride, vinyl acetate, vinyl propionate, and alkyl fumarate.

Examples of the crosslinking monomer include a diene compound and a dihydrodicyclopentadienyl group-containing (meth) compound.
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, specific examples of which include: Butadiene, isoprene, ethylidene norbornene, dicyclopentadiene, dihydrodicyclopentadiele (meth) acrylate, allyl glycidyl ether, glycidyl methacrylate, glycidyl acrylate, 2-chloroethyl vinyl ether, 2-chloroethyl vinyl acrylate, 2-chloroethyl Acrylate, 2-chloroethyl methacrylate, vinyl chloroacetate, acrylic acid, methacrylic acid, maleic acid, fumaric acid, maleic acid monomethyl ester, fumaric acid monomethyl ester Le, N- methylol acrylamide, and allyl cyano acetate.

Acrylic elastomers used for the purpose of obtaining a high level of fuel oil resistance by mixing with polyvinylidene fluoride resin include ethylene 0 to 15% by weight, vinyl carboxylate 0 to 40% by weight, acrylonitrile 0 to 20%. % By weight, and 60 to 100% by weight of an alkoxyalkyl acrylate. Preferred acrylic elastomers are alkoxyl alkyl acrylate 80
-100% by weight, acrylonitrile 0-20% by weight, ethylene 0-5% by weight and fatty acid vinyl 0-5% by weight. More preferred acrylic elastomers are alkoxyalkyl acrylates 80 to 10
0% by weight and 0 to 20% by weight of acrylonitrile are polymerized. Particularly preferred acrylic elastomer is 85 to 95% by weight of alkoxyalkyl acrylate.
And acrylonitrile in a proportion of 5 to 15% by weight.

The polyvinylidene fluoride resin used in the present invention is polyvinylidene fluoride or a copolymer of vinylidene fluoride and another copolymerizable monomer. As other copolymer monomers, for example, hexafluoropropylene,
Pentafluoropropylene, trifluoroethylene, trifluorochloroethylene, tetrafluoroethylene vinyl fluoride, perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), other olefins, acrylates, etc. Two or more are used for copolymerization.

The mixing amount of the polyvinylidene fluoride resin to the acrylic elastomer is as follows.
6 parts by weight or more, preferably 20 parts by weight or more, more preferably 30 to 80 parts by weight with respect to 00 parts by weight,
If the amount is less than 6 parts by weight, the presence of a whisker-like, fibrous or mesh-like network of the polyvinylidene fluoride resin in the acrylic elastomer is not sufficient, and it is not sufficient for the networks of the polyvinylidene fluoride resin to be connected to each other. Strength does not reach practical strength. In addition, a mixture having a polyvinylidene fluoride resin content of 30 parts by weight or more gives good tensile strength. In the expression of the tensile strength, there is no upper limit of the content of the polyvinylidene fluoride resin, but the hardness of the molded article increases as the mixing amount of the polyvinylidene fluoride resin increases,
Also, the cost of the mixture increases, so that its use as an elastomer is gradually limited.

The method for producing a thermoplastic elastomer molded article 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 bathe the mixture or the molded product at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin before removing the molded product from the mixing of the acrylic elastomer and the polyvinylidene fluoride resin. By bathing this mixture or molded product at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin, the polyvinylidene fluoride resin is
A whisker-like, fibrous or mesh-like structure is formed.

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

A specific example of a method for obtaining a molded product by bathing a mixture obtained by mixing an acrylic elastomer and a polyvinylidene fluoride resin or a molded product thereof at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin is as follows. A method in which the two are mixed at a temperature equal to or higher than the melting point of the resin and then molded.A method in which the mixture of both is molded at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin. The two are mixed at a temperature lower than the melting point of the polyvinylidene fluoride resin. Then, the mixture is bathed at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin, and then molded.The mixture is mixed at a temperature lower than the melting point of the polyvinylidene fluoride resin, and then molded at a temperature lower than the melting point of the polyvinylidene fluoride resin. Then, the molded article is bathed at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin, Etc. can be used.

The form of the polyvinylidene fluoride resin used in the present invention does not need to be particularly limited. For example, a powdery, granular, granular, block, plate, or sheet-like resin may be used. it can.

When the polyvinylidene fluoride resin is a powder, the polyvinylidene fluoride resin powder is kneaded with the acrylic elastomer at a temperature lower than the melting point of the polyvinylidene fluoride resin, and the polyvinylidene fluoride is preliminarily incorporated into the acrylic elastomer. It is also effective to mechanically disperse the resin powder in a solid state and then heat the mixture to a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin to continue kneading to obtain a mixture. This method is excellent in that the polyvinylidene fluoride resin can be mechanically and uniformly dispersed in the acrylic elastomer in advance.

Further, after the polyvinylidene fluoride resin powder is kneaded with the acrylic elastomer at a temperature lower than the melting point of the polyvinylidene fluoride resin, the sheet is directly sheeted at a temperature lower than the melting point of the polyvinylidene fluoride resin. It is also effective to provide a heating step in the molding step at a temperature higher than the melting point of the polyvinylidene fluoride resin.

Next, in the present invention, a method for producing the thermoplastic crosslinked elastic composition of the present invention containing the crosslinking agent may be used, which may contain a crosslinking agent for crosslinking the acrylic elastomer. explain. The thermoplastic crosslinked elastic composition obtained by 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 an acrylic elastomer in a whisker-like, fiber-like or mesh-like form, and has an insoluble content in diethylene glycol at 175 ° C. of 55% or more.

When an acrylic elastomer crosslinking agent 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 an agent. In the case of an acrylic elastomer in which the crosslinkable monomer is not copolymerized, an organic peroxide may be used, and a polyfunctional monomer and other additives may be used in combination.

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

When an organic peroxide is used as the crosslinking agent,
As the organic peroxide, those generally used for crosslinking rubber can be used and are not particularly limited. For example, di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, α, α-bis (T-butylperoxyisopropyl) benzene, 2,5-dimethyl2,5-di (t-butylperoxy) hexane,
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 the range of about 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the acrylic elastomer. If the amount 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 obtained composition may be impaired.

When a peroxide is used, it is more effective to use a polyfunctional monomer in combination, and the amount is preferably 0.5 part by weight or less based on 100 parts by weight of the acrylic elastomer. It is. If it exceeds 0.5 part by weight, the fluidity of the obtained composition may be impaired.

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

When a peroxide is used for crosslinking, the combined use of a radical scavenger or a thiourea derivative may be effective in balancing the properties of the crosslinked product. It is desirable that the radical scavenger be used in an amount of 3 parts by weight or less and the thiourea derivative be used in an amount of 5 parts by weight or less based on 100 parts by weight of the acrylic elastomer. If a large amount of the radical scavenger is used, the peroxide is consumed, deviating from the purpose of balancing the physical properties of the crosslinked product. The use of a large amount of a thiourea derivative also has the adverse 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, a compound generally used as a polymerization inhibitor or an antioxidant, sulfur or a sulfur-containing compound is used. Representative examples thereof include phenothiazine, 2-6-di-t-butyl-p-cresol. And sulfur compounds such as vulcanization accelerators for rubber.

In addition, various fillers, plasticizers, processing aids or stabilizers generally used in the rubber industry can be added to suit the use of the mixture. If necessary, a nitrile rubber, a hydrogenated nitrile rubber, an epichlorohydrin rubber, an ethylene propylene rubber, a butyl rubber, a fluorine rubber or the like can be mixed.

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 the amount is less than 5 parts by weight, the effect is often low,
If the amount is more than the weight part, workability may be impaired.

As the plasticizer, those which do not impair the object of the present invention, those which have an affinity for the composition, for example, α-
Olefin oligomers, polybutenes, polyethers, polyesters and the like are mentioned. Further, if desired, a mixture with other rubbers, for example, various rubbers having excellent fuel oil resistance, is also possible.

The method for producing the thermoplastic crosslinked elastic composition of the present invention described above uses the acrylic elastomer 1
From a raw material system containing 00 parts by weight, 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 not lower than the melting point of the polyvinylidene fluoride resin. And (Y) simultaneously shearing while substantially decomposing the cross-linking agent of the mixture containing at least the acrylic elastomer and the kneading the cross-linking 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 performed in the order of the steps (X) to (Y),
It is manufactured by the method of performing the steps (X) and (Y) simultaneously in the order of the steps (Y) and (X).

In the above step (X), the mixing of the acrylic elastomer and the polyvinylidene fluoride resin includes:
The equipment used for kneading the rubber and the thermoplastic resin described above is usually used. In the step (X), the mixture obtained by mixing the acrylic elastomer and the polyvinylidene fluoride resin is heated to the melting point of the polyvinylidene fluoride resin or more. The same method as the method of bathing at the above temperature can be used.

In the step (Y), the step of applying shear while simultaneously substantially decomposing the crosslinking agent of the mixture containing at least the acrylic elastomer and the crosslinking agent (Y-1)
Step (Y-2)) or a step of substantially decomposing the cross-linking agent while kneading the cross-linking agent into the system containing at least the acrylic elastomer.

As a specific method of the Y-1 step, a mixture of an acrylic elastomer containing a cross-linking agent and polyvinylidene fluoride resin is charged into a closed mixer and mechanically sheared to decompose the cross-linking agent. Increasing the temperature to substantially decompose the crosslinking agent to obtain a composition containing 55% or more of an insoluble component in diethylene glycol at 175 ° C. in the mixture.

As a specific method of the step Y-2, an acrylic elastomer is put into a closed mixer, heated to a decomposition temperature of the crosslinking agent while applying shear, and then the crosslinking agent is added and kneaded. A method of decomposing a crosslinking agent, kneading another crosslinking agent, and obtaining a composition containing 55% or more of an insoluble content in diethylene glycol at 175 ° C.

Next, a method for producing the thermoplastic crosslinked elastic body molded article of the present invention will be described. The thermoplastic crosslinked elastic molded article produced according to 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 an acrylic elastomer in a whisker-like, fibrous or mesh-like form, and has an insoluble content in diethylene glycol at 175 ° C. of 55% or more.

The method for producing a thermoplastic crosslinked elastic body molded article of the present invention is a method for producing a molded article from the above thermoplastic crosslinked elastic body composition, or the above steps (X) to (Y). , The order from the step (Y) to the step (X), or the step (X) and the step (Y) are simultaneously performed to produce a molded article.

The thermoplastic cross-linked elastic composition and the cross-linked elastic molded article produced according to the present invention are obtained by forming a polyvinylidene fluoride resin in an acrylic elastomer into a whisker-like, fibrous or mesh-like form in an acrylic elastomer. Since the acrylic elastomer is dispersed and the acrylic elastomer is cross-linked by a cross-linking agent, and the cross-linking agent has a substantially decomposed structure, the physical properties of the molded product such as compression set are good.

Further, the thermoplastic crosslinked elastic composition and the crosslinked elastic molded article produced according to the present invention have a temperature of 175 ° C.
55% insolubles in diethylene glycol
As described above, the content is preferably 55% to 70%, and if the insoluble content is less than 55%, it is difficult to obtain excellent compression set. Also, when it exceeds 70%, the compression set is good,
Moldability tends to decrease.

Further, the thermoplastic crosslinked elastic composition and the crosslinked elastic molded article produced according to the present invention are 175
Volume change (ΔV) after immersion in diethylene glycol at 22 ° C. for 22 hours is 50 to 250%, preferably 10 to 250%.
If it is less than 50%, the moldability is poor, and if it exceeds 250%, it is difficult to obtain excellent compression set.

The thermoplastic elastic molded article, crosslinked elastic composition, and crosslinked elastic molded article produced according to the present invention are useful as materials suitable for obtaining various engineering articles. Packing, gasket, hose,
It can be applied to tubes and the like.

[0049]

EXAMPLES The present invention will be specifically described below with reference to examples. Examples 1 to 7 and Comparative Examples 1 to 3 Using an acrylic elastomer A and a polyvinylidene fluoride resin, by the compounding formulation and the molding method shown in Table 1,
The thermoplastic elastomer composition was molded, and the physical properties of the molded product were measured. Table 1 shows the results. The acrylic elastomer A, polyvinylidene fluoride resin, molding method and test method are shown at the end.

From the results shown in Table 1, it can be confirmed that practical strength is exhibited without mixing the conventional vulcanization step by mixing at least 6 parts by weight of polyvinylidene fluoride resin with 100 parts by weight of acrylic elastomer.

Examples 8 to 13 and Comparative Examples 4 to 5 By using the acrylic elastomer B and the polyvinylidene fluoride resin, according to the formulation and the molding method shown in Table 2,
The thermoplastic elastomer composition was molded, and the physical properties of the molded product were measured. Table 2 shows the results. Acrylic elastomer B, polyvinylidene fluoride resin, molding method and test method are shown at the end.

From the results shown in Table 2, it is recognized that practical strength is exhibited without mixing the conventional vulcanization step by mixing at least 6 parts by weight of polyvinylidene fluoride resin with 100 parts by weight of the acrylic elastomer. Further, a thermoplastic elastomer composition (Example 10) obtained by kneading a conventional acrylic elastomer crosslinking agent in advance and decomposing it during mixing of the acrylic elastomer and the polyvinylidene fluoride resin (Example 10) also shows sufficient performance. It is recognized that.

(1) -1 Production of Acrylic Elastomer A In a 130 liter autoclave, 2120 g of polyvinyl alcohol and 86 g of sodium acetate were dissolved to prepare a solution.
g of an aqueous solution adjusted to be 0.1 g, and while stirring, 8.6 kg of vinyl acetate and 34.6 kg of 2-methoxyethyl acrylate were added to emulsify. After the inside of the autoclave was replaced with nitrogen gas, ethylene monomer was injected from above. did. The ethylene pressure is 45 kg / cm ² at a polymerization temperature of 55 ° C.
It was adjusted to become. Separately dispensed the polymerization initiator aqueous solution several times from the injection port, stopped the polymerization in about 10 hours,
After demonomerization, coagulation and dehydration with a 3% aqueous borax solution, the dehydrated and dried polymer is converted to an acrylic elastomer A
And

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

An aqueous solution of a polymerization initiator was separately injected from an injection port to advance polymerization, and the injection was completed in 12 hours. An aqueous solution of Glauber's salt was added to the resulting polymer emulsion to coagulate the polymer, which was washed with water, dried and dried to obtain an acrylic elastomer B.

(2) Polyvinylidene fluoride resin As shown in Table 1, powdery polyvinylidene fluoride KYNAR 741: manufactured by Penwort Co., Ltd., melting point (165 to 17)
0 ° C.).

(3) Molding Method (Molding Method A) Acrylic elastomer is treated at a surface temperature of 40
After winding around a roll at ℃ and kneading the finely powdered polyvinylidene fluoride resin, the filler was further kneaded. The obtained mixture was wound around a roll having a surface temperature of 170 ° C. for 5 minutes, and 3/4 cutting was performed once right and left once a minute, followed by sheeting and cooling at room temperature. The obtained sheet was pressed at 170 ° C. for 10 minutes using a press molding machine. Further, it was water-cooled for 10 minutes in a pressurized state and molded. (Molding method B) Molding was carried out without performing the operation using a roll having a surface temperature of 170 ° C. in molding method A. (Molding Method C) The molding was carried out at a temperature of 150 ° C. in press molding in Molding Method A. (Molding Method D) Polyvinylidene fluoride resin powder is mixed with an acrylic elastomer using an 8-inch roll at a surface temperature of 40 ° C. together with a crosslinking agent and other fillers. Molding was performed.

(4) Physical properties After molding, the specimen was left at room temperature for one day, and then subjected to JIS K63.
01, various physical properties were measured.

Fuel oil resistance: 4% in a mixed liquid (E-20) of Fuel C (isooctane / toluene: 50/50% by volume) and Fuel C / ethanol: 80/20% by volume.
The volume change (ΔV) after immersion at 0 ° C. for 70 hours was determined.

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

[0061]

(Equation 1)

However, W = 100 + 175 ° C. The number of parts of the compound dissolved in diethylene glycol Diethylene glycol resistance: The volume change (ΔV) after immersion in diethylene glycol at 175 ° C. for 22 hours was measured and determined by the following equation (II).

[0063]

(Equation 2)

Where V ₁ = weight in air before immersion−weight in water before immersion V ₂ = weight in air after immersion−weight in water after immersion

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

◎: A large amount of mesh development was observed. ：: A small mesh development was observed.

(5) -2 Form of Thermoplastic Molded Product FIG. 2 shows a molded product of Example 3 of the present invention (a flake: a thickness of 50 n).
m) shows an electron micrograph (magnification: 15,000 times) showing the particle structure of the polyvinylidene fluoride resin, and FIGS. 3 to 5 show the compositions corresponding to Examples 3, 4 and Comparative Example 3, respectively. In order to make the presence of the vinylidene fluoride resin easier to understand, a similar electron micrograph showing the particle structure of the polyvinylidene fluoride resin in the molded article excluding carbon black is shown.

[0068]

[Table 1]

[0069]

[Table 2]

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

[0071]

As described above, the thermoplastic elastomer molded article produced according to the present invention is a mixture of an acrylic elastomer and a polyvinylidene fluoride resin, wherein the polyvinylidene fluoride resin is one of the acrylic elastomers. Because they are dispersed in the form of whiskers, fibers or meshes,
Even if the mixture is not crosslinked by vulcanization, only by mixing the acrylic elastomer and the polyvinylidene fluoride resin, it is possible to obtain an effect having excellent tensile strength, elasticity, fuel oil resistance and the like and practical performance.

Further, the crosslinked elastic composition and the crosslinked elastic molded article produced according to the present invention are obtained by crosslinking an acrylic elastomer with a crosslinking agent, and in the acrylic elastomer, a polyvinylidene fluoride resin has a whisker-like shape. Since it is dispersed in a fibrous or network form, in addition to an improvement in compression set due to cross-linking, it has excellent tensile strength, elasticity, fuel oil resistance and the like, and has an effect having practical performance.

As described above, according to the production method of the present invention,
Even without the conventional vulcanization step, the above-mentioned thermoplastic elastic molded article, crosslinked elastic composition, and crosslinked elastic molded article having practical performance can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing an example of a thermoplastic elastic molded article produced according to the present invention.

FIG. 2 is an electron micrograph (magnification: 15, 15) showing the particle structure of polyvinylidene fluoride resin in the molded product of Example 3.
000 times).

FIG. 3 is an electron micrograph (magnification: 15,000 times) showing the particle structure of a polyvinylidene fluoride resin in a molded product having a composition corresponding to that of Example 3 and excluding carbon black.
It is.

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

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Acrylic elastomer 2 Part in which polyvinylidene fluoride resin exists in high concentration 3 Polyvinylidene fluoride resin which expanded in a whisker-like, fibrous or mesh-like form

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (Reference) C08L 27:16)

Claims (3)

[Claims] 1. A method for producing a thermoplastic elastomer 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, comprising: Heating the mixture or the molded product at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin from mixing of the polyvinylidene fluoride resin to forming a molded product or after molding to form a molded product. A method for producing a plastic elastic molded article. 2. 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, wherein (X) at least an acrylic resin A step of bathing the mixture containing the elastomer and the polyvinylidene fluoride resin at a temperature equal to or higher than the melting point of the polyvinylidene fluoride resin,
(Y) a step of applying shear while simultaneously substantially decomposing the cross-linking agent of the mixture containing at least the acrylic elastomer and the cross-linking agent, or simultaneously adding the cross-linking agent while kneading the cross-linking agent to the system containing at least the acrylic elastomer. One of the steps of substantially decomposing,
Step (X) to step (Y), step (Y) to step (X)
A method for producing a thermoplastic crosslinked elastic composition, comprising performing the steps in order, or steps (X) and (Y) simultaneously. 3. 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. (X) bathing a mixture containing at least the acrylic elastomer and the polyvinylidene fluoride resin at 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 the acrylic elastomer and the crosslinking agent. One step of simultaneously applying shear while substantially decomposing the compound, or substantially decomposing the cross-linking agent simultaneously while kneading the cross-linking agent into at least the system containing the acrylic elastomer, From the process to the (Y) process,
A method for producing a molded article of a thermoplastic crosslinked elastic material, wherein the steps (Y) to (X) are performed in order, or the steps (X) and (Y) are simultaneously performed.