JP7218636B2 - RESIN COMPOSITION AND METHOD FOR MANUFACTURING THERMALLY VERY CROSSLINKABLE MOLDED PRODUCT USING SAME RESIN COMPOSITION - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin composition having thermoreversible crosslinkability and a method for producing a thermoreversibly crosslinkable molded article using the resin composition.

For the purpose of improving the practical physical properties of resins, it is common practice to introduce a crosslinked structure into resins to increase cohesive strength of resins and improve physical properties such as heat resistance and mechanical strength.
Resins into which a crosslinked structure has been introduced are prone to gelation and have problems in terms of moldability. Therefore, the cross-linking step is conventionally performed after the molding is completed, and specific methods include a method of irradiating radiation, application of a reaction using moisture in the air, and the like.
However, these methods have problems such as insufficient cross-linking immediately after molding and cost issues. In addition, from the standpoint of environmental protection and resource conservation, the requirements for the recycling of molded products, punched parts, and burrs are becoming more and more stringent. , was considered a problem.

In order to solve these problems, for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 6-57062) discloses that melt molding is possible without forming a crosslinked structure at the processing temperature, and rapid crosslinking occurs during the cooling and solidification process after molding. A thermoreversible crosslinkable resin composition capable of forming a structure and completely dissociating the crosslinks by heating to the molding temperature again, that is, having extremely high crosslink formation reaction rate and crosslink dissociation reaction rate, and a molded article using the same is proposed.

JP-A-6-57062

Patent Document 1 states that a metal salt of an organic carboxylic acid is suitably used as a reaction accelerator used in a thermoreversibly crosslinkable resin composition and a molded article using the same.
In recent years, due to environmental concerns, resin compositions and moldings using the same are sometimes required to have a reduced metal ion content or be free of metal ions, but past inventions have not been able to meet such demands. Can not.
Also, in this prior art, various tertiary amine compounds are exemplified as reaction accelerators, but these tertiary amine compounds actually have low activity as reaction accelerators, and some have almost no activity. be.

The present invention solves the problems of the prior art, is free of metal ions, has excellent molding properties, and at the same time, has a thermoreversible crosslinkability with a strong crosslinked structure at room temperature, and uses the same. An object of the present invention is to economically and advantageously provide a thermally reversibly crosslinkable molded article.

As a result of extensive studies in order to solve the above problems, the present inventors have found that a composition comprising a specific polyolefin and a polyhydric alcohol is blended with a reaction accelerator containing a compound having a specific structure in the molecule. have discovered a metal ion-free, thermoreversibly crosslinkable resin composition and a method for producing a thermoreversibly crosslinkable molding using the same, and have completed the present invention based on these findings.

That is, according to the present invention, a resin composition containing the following component (a), component (b) and component (c),
The component (a) is a polyolefin having at least one carboxylic anhydride structure, and the concentration of the carboxylic anhydride structure in the polyolefin is 0.1 to 20% by mass,
The component (b) is a polyhydric alcohol compound having at least two hydroxyl groups in the molecule,
The component (c) is a compound having a structure represented by the following general formula (1) and is a reaction accelerator excluding compounds having a structure represented by the following general formula (2),
The molar ratio of the hydroxyl group unit in the polyhydric alcohol compound as the component (b) to the unit derived from the carboxylic anhydride structure in the polyolefin as the component (a) is 0.01 to 10. is in the range of
Provide a resin composition characterized in that the reaction accelerator which is the component (c) is contained in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the polyolefin which is the component (a). be done.
General formula (1): -N=C (-N<)-
General formula (2): -N=C(-NH ₂ )-

In the resin composition of the present invention, the reaction accelerator may be a compound represented by the following general formula (3).
General formula (3): R ¹ -N=C(-NR ² R ³ )-R ⁴
In the above general formula (3),
R ¹ is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group has a ring structure. may form, the ring structure may form a heterocyclic ring structure,
R ² is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group has a ring structure. may form, the ring structure may form a heterocyclic ring structure,
R ³ is a group selected from a hydrocarbon group having 1 to 10 carbon atoms and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group forms a ring structure; may be, the ring structure may form a heterocyclic ring structure,
R ⁴ is a group selected from a hydrogen atom, a halogen group, an ester group, a nitro group, a cyano group, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent; and the hydrocarbon group may form a ring structure, and the ring structure may form a heterocyclic ring structure.

In the resin composition of the present invention, the reaction accelerator is at least one compound selected from the group consisting of imidazole compounds, benzimidazole compounds, diazabicyclononene compounds, diazabicycloundecene compounds, and imidazoline compounds. may be

According to the present invention, there is provided a method for producing a thermoreversibly crosslinkable molded article, characterized in that the resin composition is melt-molded and a crosslinked structure is formed in the cooling process.

The resin composition of the present invention is free of metal ions due to the presence of a reaction accelerator containing a highly active compound, has excellent moldability, and at the same time has a thermoreversible crosslinkability in which the crosslinked structure at room temperature is strong. It is possible to economically and advantageously provide a product and a thermoreversibly crosslinkable molded product using the same.

The present invention provides a resin composition containing the following components (a), (b) and (c),
The component (a) is a polyolefin having at least one carboxylic anhydride structure, and the concentration of the carboxylic anhydride structure in the polyolefin is 0.1 to 20% by mass,
The component (b) is a polyhydric alcohol compound having at least two hydroxyl groups in the molecule,
The component (c) is a compound having a structure represented by the following general formula (1) and is a reaction accelerator excluding compounds having a structure represented by the following general formula (2),
The molar ratio of the hydroxyl group unit in the polyhydric alcohol compound as the component (b) to the unit derived from the carboxylic anhydride structure in the polyolefin as the component (a) is 0.01 to 10. is in the range of
The resin composition is characterized in that the reaction accelerator which is the component (c) is contained in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the polyolefin which is the component (a). It is.
General formula (1): -N=C (-N<)-
General formula (2): -N=C(-NH ₂ )-
Since the constituent requirements and features of the present invention have been outlined above, each requirement of the present invention will be specifically described in detail below as a mode for carrying out the present invention.

1. Component (a): Polyolefin having at least one carboxylic anhydride structure Component (a), a polyolefin having at least one carboxylic anhydride structure, is a polyolefin having at least one carboxylic anhydride structure. There is no particular limitation if it is, and it may have a carboxylic anhydride structure in the main chain of the molecule by copolymerization of the carboxylic anhydride and the olefin, or graft modification of the carboxylic anhydride to the polyolefin. Examples thereof include ethylene-maleic anhydride-acrylic acid ester terpolymers and modified polyolefins grafted with unsaturated carboxylic acid anhydrides shown below.

Examples of those having a carboxylic anhydride structure in the main chain of the molecule obtained by copolymerization of a carboxylic anhydride and an olefin include ethylene and a radically polymerizable α,β-unsaturated dicarboxylic anhydride comonomer. A copolymer can be exemplified.
Examples of α,β-unsaturated dicarboxylic anhydride comonomers include anhydrides of α,β-unsaturated dicarboxylic acids such as maleic acid and citraconic acid, among which maleic anhydride is preferred.

The polyolefin having at least one carboxylic anhydride structure may be obtained by copolymerizing other radically polymerizable comonomers in addition to the carboxylic anhydride and the olefin.
Other radically polymerizable comonomers include acrylate comonomers, methacrylate comonomers, carboxylic acid vinyl ester comonomers, and the like.
Specific examples of the acrylate comonomer include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, etc. Among them, methyl acrylate and ethyl acrylate are preferred.
Specific examples of the methacrylate comonomer include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, etc. Among them, methyl methacrylate and ethyl methacrylate are preferable.
Specific examples of the carboxylic acid vinyl ester comonomer include vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, etc. Among them, vinyl acetate is preferable.

Specific examples of polyolefins having at least one carboxylic acid anhydride structure include binary copolymers such as ethylene-maleic anhydride copolymers.
Examples of terpolymers include ethylene-maleic anhydride-methyl acrylate copolymer, ethylene-maleic anhydride-ethyl acrylate copolymer, and ethylene-maleic anhydride-methyl methacrylate copolymer. , ethylene-maleic anhydride-ethyl methacrylate copolymer, and ethylene-maleic anhydride-vinyl acetate copolymer.
Furthermore, multicomponent copolymers in which the above comonomers are combined are also included.
Among the above copolymers, ethylene-maleic anhydride-methyl acrylate copolymer, ethylene-maleic anhydride-ethyl acrylate copolymer, ethylene-maleic anhydride-methyl methacrylate copolymer, ethylene-anhydride A preferred example is a maleic acid-ethyl methacrylate copolymer.
The content of the above comonomer is preferably such that the amount of polar groups is 5 to 40 mass %. If the amount of polar groups is less than 5% by mass, the adhesion of the resin composition tends to be insufficient, and if it exceeds 40% by mass, the durability of the resin composition tends to decrease.

Modified polyolefins obtained by modifying polyolefins with carboxylic anhydrides are examples of polyolefins obtained by graft-modifying and adding carboxylic anhydrides. Polyolefins used for producing modified polyolefins include homopolymers of olefins such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, or two or more of these olefins. They are random or block copolymers or binary or multi-component copolymers of vinyl acetate, acrylic acid, methacrylic acid, acrylic acid esters, methacrylic acid esters, etc., containing these olefins as main components.
Specifically, high-density polyethylene, low-density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-vinyl acetate copolymer, ethylene-butene-1 copolymer, propylene-butene-1 copolymer, ethylene - acrylic acid ester copolymer, ethylene-maleic anhydride-acrylic acid ester copolymer, and the like. You may use these individually or in mixture of 2 or more types.

Examples of unsaturated carboxylic anhydrides used as graft monomers include maleic anhydride, itaconic anhydride, endic anhydride, citraconic anhydride, 1-butene-3,4-dicarboxylic anhydride, and 18 carbon atoms. alkenyl succinic anhydride having a double bond at the terminal, and alkadienyl succinic anhydride having a double bond at the terminal and having 18 or less carbon atoms. These may be used singly or in combination of two or more. Of these, maleic anhydride and itaconic anhydride are preferred.

Any known grafting method can be employed. That is, a solution grafting method in which a radical initiator and an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride are mixed and reacted in a solution of a polyolefin dissolved in a solvent, and a melt grafting method in which a solvent is not present and is modified in an extruder. radiation grafting methods using electron beams and the like can be used. Furthermore, after graft modification by these methods, it is preferable to remove unreacted substances, reaction by-products, and the like by solvent washing or the like.

The component concentration of the carboxylic anhydride structure in the polyolefin that is the component (a) must be in the range of 0.1 to 20% by mass, preferably in the range of 1 to 10% by mass. It is more preferably in the range of up to 5% by mass, and a more preferred embodiment is 1.3 to 3.6% by mass. If the component concentration of the carboxylic anhydride structure is less than 0.1% by mass, the crosslinking density, which is the object of the present invention, will be insufficient, which is not preferred. On the other hand, if it exceeds 20% by mass, properties such as flexibility and mechanical strength are impaired, which is not preferable.
Furthermore, the MFR of the polyolefin used in the present invention is measured according to JIS K7210-1 (2014) under the conditions of a temperature of 190 ° C. and a load of 21.18 N (2.16 kg), and is 0.1 to 1000 g / 10 minutes. is preferred. Outside this range, it is difficult to obtain a resin composition that meets the object of the present invention.

2. Component (b): Polyhydric alcohol compound having at least two hydroxyl groups in the molecule The polyhydric alcohol compound having at least two hydroxyl groups in the molecule, which is the component (b), includes, for example,
Glycols such as ethylene glycol, diethylene glycol and triethylene glycol;
Alcohol compounds such as 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, trimethylolethane, trimethylolpropane, di(trimethylolpropane), and pentaerythritol ;
sugars such as arbitol, sorbitol, xylose, arabinose, glucose, galactose, sorbose, fructose, palatinose, maltotriose, malezitose;
Saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyolefin oligomer having a plurality of hydroxyl groups, ethylene-hydroxyethyl (meth)acrylate [(meth)acrylate means methacrylate and acrylate. Same hereafter] A polymer having a plurality of hydroxyl groups in its molecule, such as a copolymer;
1,3-dihydroxypropane, 2,2-dimethyl-1,3-dihydroxypropane, trimethylolethane, 1,1,1-trimethylolpropane, 1,1,1-trimethylolhexane, 1,1,1- Trimethyloldodecane, 2-cyclohexyl-2-methylol-1,3-dihydroxypropane, 2-(p-methylphenyl)-2-methylol-1,3-dihydroxypropane, pentaerythritol, glycerin, diglycerin, hexadiglycerin , octaglycerin, and polyoxyalkylene compounds obtained by addition reaction of ethylene oxide or propylene oxide to decaglycerin;
Glycerin monostearate, glycerin monooleate, glycerin monolaurate, glycerin monocaprylate, glycerin monohexanoate, glycerin monophenethyl ester, glycerin monopropionate, diglycerin monostearate, diglycerin distearate, di glycerin monooleate, diglycerin monohexanoate, diglycerin dioctanoate, tetraglycerin monostearate, tetraglycerin tristearate, tetraglycerin tetrastearate, tetraglycerin trihexanoate, tetraglycerin monophenethyl ester, Hexaglycerin monostearate, hexaglycerin distearate, hexaglycerin penttearate, hexaglycerin trioleate, hexaglycerin monolaurate, hexaglycerin pentalaurate, decaglycerin monostearate, decaglycerin octastearate, decaglycerin penta Polyglycerin alkyl esters such as oleate, decaglycerin dilaurate, pentadecaglycerin distearate, pentadecaglycerin decoleate, octadecaglycerin tetrastearate;
Sorbitan alkyls such as sorbitan monostearate, sorbitan monooleate, sorbitan monolaurate, sorbitan monocaprylate, sorbitan monohexanoate, sorbitan monophenethyl ester, sorbitan monopropionate, sorbitan tristearate, sorbitan tetrastearate and esters.
The melting point of these polyhydric alcohol compounds is preferably 300° C. or less in consideration of thermal deterioration of the polyolefin of component (a). Moreover, these polyhydric alcohol compounds can also be used individually or in combination of 2 or more types.

The polyhydric alcohol of the component (b) of the resin composition of the present invention has hydroxyl groups contained in the polyhydric alcohol compound relative to units derived from the unsaturated carboxylic anhydride structure contained in the polyolefin of the component (a). may be in the range of 0.01 to 10, preferably in the range of 0.05 to 5, more preferably in the range of 0.1 to 3, and as a further preferred embodiment 1 .2 to 1.6. If this molar ratio is less than 0.01, it tends to be insufficient to introduce an effective amount of the crosslinked structure into the resin composition, and if it exceeds 10, it may be processed during molding in some cases. The crosslinked structure does not completely dissociate at temperature, and molding tends to be extremely difficult. Moreover, the polyhydric alcohol may bleed out from the resin composition.

3. Component (c): Reaction Accelerator The reaction accelerator, which is component (c), is a compound having a structure represented by the following general formula (1) and having a structure represented by the following general formula (2). It is a reaction accelerator that removes the compound having the acid anhydride group, and is a compound that accelerates the reaction with the acid anhydride group. As such a reaction accelerator, there are various things, but the following organic amine compounds can be mentioned as highly active organic compounds.
General formula (1): -N=C (-N<)-
General formula (2): -N=C(-NH ₂ )-

Among the above reaction accelerators, compounds represented by the following general formula (3) are preferred.
General formula (3): R ¹ -N=C(-NR ² R ³ )-R ⁴
In the above general formula (3),
R ¹ is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group has a ring structure. may form, the ring structure may form a heterocyclic ring structure,
R ² is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group has a ring structure. may form, the ring structure may form a heterocyclic ring structure,
R ³ is a group selected from a hydrocarbon group having 1 to 10 carbon atoms and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group forms a ring structure; may be, the ring structure may form a heterocyclic ring structure,
R ⁴ is a group selected from a hydrogen atom, a halogen group, an ester group, a nitro group, a cyano group, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent; and the hydrocarbon group may form a ring structure, and the ring structure may form a heterocyclic ring structure.

Furthermore, the reaction accelerator is preferably at least one compound selected from the group consisting of imidazole compounds, benzimidazole compounds, diazabicyclononene compounds, diazabicycloundecene compounds, and imidazoline compounds.

Specific examples of reaction accelerators include 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, imidazole, 1-methyl imidazole, 2-methylimidazole, 4-methylimidazole, 1-ethylimidazole, 2-ethylimidazole, 1-propylimidazole, 1-butylimidazole, 2-butylimidazole, N-acetylimidazole, 1-allylimidazole, N-tert -butoxycarbonylimidazole, 1-tert-butylimidazole, 1-benzylimidazole, 1-isopropylimidazole, 1,2-dimethylimidazole, benzimidazole, 1-methylbenzimidazole, 2-methylbenzimidazole, 5-methylbenzimidazole, 5,6-dimethylbenzimidazole, 1-benzyl-2-methylimidazole, 1,1′-carbonyldiimidazole, 1-(2-cyanoethyl)-2-methylimidazole, 1-(2-cyanoethyl)-2-un Decylimidazole, 1,2-dimethylbenzimidazole, 1,2-dimethyl-5-nitroimidazole, 4,5-diphenylimidazole, 2-ethyl-1H-benzimidazole, ethyl 4-imidazolecarboxylate, 2-ethyl-4 -methylimidazole, 2-heptadecylimidazole, hypoxanthine, albendazole, purine, imidazoline, 2-methyl-2-imidazoline, 2-ethyl-2-imidazoline, 2-propyl-2-imidazoline, 2-phenylimidazoline, 2 -Benzylimidazoline, naphazoline, 5-pyrazolone, compounds in which various functional groups such as alkyl groups, phenyl groups, halogen groups, ester groups, nitro groups, and cyano groups are further added to the above compounds, the above compounds, and the above compounds Polymer compounds containing compounds further added with various functional groups such as alkyl groups, phenyl groups, halogen groups, ester groups, nitro groups, cyano groups, etc. as monomers, salts obtained by reacting the above compounds with various acids, imidazolium salts etc.

The reaction accelerator which is component (c) may be contained in the resin composition in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the polyolefin which is component (a), and is 0.01 to 7 parts by mass. is preferably contained in the range of 0.05 to 5 parts by mass, more preferably in the range of 0.5 to 1.5 parts by mass. If this amount is less than 0.001 parts by mass, it tends to be insufficient to introduce a crosslinked structure into the resin composition in an effective amount, and if it exceeds 10 parts by mass, molding may be conducted in some cases. In some cases, the crosslinked structure is not completely dissociated at the processing temperature, and molding tends to be extremely difficult. In addition, the reaction accelerator may bleed out from the resin composition.

The acid anhydride structure contained in the polyolefin used in the resin composition of the present invention reacts with the hydroxyl groups contained in the polyhydric alcohol to form a monoester, thereby introducing a crosslinked structure into the resin composition. It is considered to be a thing. A composition consisting of two components, a polyolefin containing an acid anhydride group and a polyhydric alcohol, exhibits the property of a so-called thermoreversible crosslinkable resin in which the crosslinked structure dissociates at high temperatures and forms a crosslinked structure again upon cooling. , the crosslink formation reaction rate and the crosslink dissociation reaction rate are extremely slow, and sufficient physical properties cannot be exhibited under general thermoforming processing conditions.

However, in the present invention, a reaction accelerator is added to the composition to increase the cross-linking reaction rate and the cross-linking dissociation reaction rate, thereby making the composition practically usable. This is thought to be because the reaction accelerator increases the reaction rate between the acid anhydride structure contained in the polyolefin and the hydroxyl group of the polyhydric alcohol. A thermoreversibly crosslinkable resin composition exhibiting sufficient physical properties can be obtained.

Although the resin composition of the present invention varies depending on the type of polyolefin used, by selecting an appropriate molding temperature, the ester bonds are dissociated, making it possible to exhibit good moldability. When solidified by cooling, the ester bond is quickly formed again and the cross-linking reaction progresses, and it is presumed that the cross-linked structure is introduced into the interior of the resulting molded product and exerts the effect of increasing its strength. However, this mechanism has not been completely elucidated, and the present invention is not bound by this.

4. Method for Producing Resin Composition The resin composition of the present invention is molded by melt-kneading. A crosslinked structure is not formed during this molding process.

5. Method for Producing Thermoreversibly Crosslinkable Molded Article The resin composition of the present invention can be formed into a thermoreversibly crosslinkable molded article by melt-molding the resin composition and forming a crosslinked structure in the cooling process. After the resin composition of the present invention is molded into pellets, plates, films, or various moldings by injection molding, it forms a crosslinked structure in the cooling and solidification process, increases cohesive force, and improves mechanical strength. In addition, even if a crosslinked structure is once formed, this structure is dissociated by melting to recover moldability, and a crosslinked structure is formed again in the process of cooling and solidifying after a new molding, resulting in high-strength thermoreversible crosslinking. A flexible molded product can be obtained.

The molding conditions for the resin composition and the thermoreversibly crosslinkable molded article may vary depending on the type of resin and the type of alcohol compound, but generally the extruder and die temperature should be set to a resin temperature of 200° C. or higher. By setting the temperature to be higher than the melting point of the polyhydric alcohol, the cross-linking in the resin composition is dissociated and melt molding becomes possible. At the time of solidification by cooling, the crosslinking reaction proceeds rapidly due to the curing by the reaction accelerator, and a thermoreversibly crosslinkable molded article into which a crosslinked structure is introduced is obtained. Therefore, the strength of the resin is improved, and a thermoreversibly crosslinkable molded article that can be used in various applications can be obtained.
Thermoreversibly crosslinkable moldings include, for example, various films, various tapes (especially dicing tapes), blow moldings, injection moldings, laminate moldings, etc. Various packaging materials, containers, machine parts, industrial materials, daily necessities, etc. can be used. It can also be used as a resin modifier to improve environmental stress cracking resistance (ESCR), mechanical strength and the like.

In the following, the present invention will be described in more detail with examples and comparative examples, demonstrating the superiority of the present invention and the superiority of the configuration of the present invention, but the present invention is limited by these examples. not a thing
The measurement methods used in Examples and Comparative Examples are as follows.

[Physical property measurement method]
(1) MFR
It was measured under conditions of a temperature of 190° C. and a load of 21.18 N (2.16 kg) in accordance with JIS K7210-1 (2014).

(2) Storage modulus G' at 130°C
A press-molded sample of 10 mm×50 mm×3 mm thick was prepared from the resin composition, and solid viscoelasticity measurement (Rectoangular torsion method) was performed using a rheometer (ARES) manufactured by Rheometric Scientific. Measurements were taken while increasing the temperature, and the value of the storage modulus G' when reaching 130°C was recorded. The higher the storage elastic modulus G' at 130°C, the higher the heat resistance of the crosslinked structure.

(3) Elastic Retention Temperature A press-molded sample of 10 mm×50 mm×3 mm thick was prepared from the resin composition, and solid viscoelasticity was measured (rectoangular torsion method) with a rheometer (ARES) manufactured by Rheometric Scientific. The temperature was measured while increasing the temperature, and the temperature at which the storage elastic modulus G' decreased to 1,000 Pa was defined as the "elasticity retention temperature." The higher the elastic retention temperature, the higher the heat resistance (heat resistance limit) of the crosslinked structure.

(4) Comprehensive Evaluation The resin composition was comprehensively evaluated according to the following criteria.
When the storage elastic modulus G′ at 130° C. was 5.0×10 ⁴ Pa or more, it was evaluated as “◯”, and when it was less than 5.0×10 ⁴ Pa, it was evaluated as “×”.
In addition, when the elastic retention temperature was 170°C or higher, it was evaluated as "◯", and when it was lower than 170°C, it was evaluated as "x".
In addition, judging from the raw materials of the resin composition, those that theoretically do not contain metal ions are indicated by "○", and those that contain metal ions are indicated by "x".
When all of the above evaluation results are "O", the overall evaluation is "O", and when at least one of the above evaluation results is "X", the overall evaluation is "X".

(Example 1)
Ethylene-maleic anhydride-methyl acrylate terpolymer A ( Hereinafter, a terpolymer A) was produced. Quantification of the maleic anhydride structure was determined by infrared absorption spectroscopy.
Table 1 shows the composition of the terpolymer A and the physical property values in solid viscoelasticity measurement.

Next, to the terpolymer A, di(trimethylolpropane) was added as a polyhydric alcohol so as to be 3.7% by mass relative to the terpolymer A. At this time, the molar ratio of di(trimethylolpropane) molecules to units derived from the maleic anhydride structure is 0.4, and the molar ratio of hydroxyl groups to units derived from the maleic anhydride structure is 1.6.
Furthermore, to the terpolymer A, imidazole was added as a reaction accelerator so as to be 1 part by mass with respect to 100 parts by mass of the terpolymer A.
These three components were dry-blended in a tumbler, melt-kneaded at 190° C. using a 30 mmφ twin-screw extruder, and pelletized to obtain a resin composition.
Table 2 shows the composition of this resin composition. In Table 2, Di(TMP) means di(trimethylolpropane), 1,10-DEC means 1,10-decanediol, Im means imidazole, 1MIm means 1-methylimidazole. 2MIm means 2-methylimidazole, 2E4MIm means 2-ethyl-4-methylimidazole, DBU means 1,8-diazabicyclo[5.4.0]-7-undecene, N, N-DMA means N'N-dimethylaniline, TOA means trioctadecylamine, and metal salt (a) is Na salt of ethylene-methacrylic acid (18% by mass) copolymer (10% by mass of methacrylic acid Neutralization, MFR: 3.0 g/10 min).

The measured values of solid viscoelasticity measurement are as follows: raw material resin alone (terpolymer A) cannot be measured for storage elastic modulus G' at 130°C (because the elastic retention temperature is 130°C or lower), and the elastic retention temperature is 109°C. On the other hand, in the pellets of the resin composition of the present invention, the storage elastic modulus G' at 130 ° C. was 9.6 × 10 ⁴ Pa and the elastic retention temperature was 193 ° C. It was confirmed that the structure was formed. Based on the above results, the evaluation results of the above three items are that the storage elastic modulus G' at 130 ° C. is "○", the elastic retention temperature is "○", and the raw material of this resin composition does not contain metal ions. Therefore, the environmental compatibility was given "○", and the comprehensive evaluation was given "○".
Table 3 shows the evaluation results of the resin composition.

A film was also molded using this resin composition.
For molding, a film molding machine having a 25 mm diameter extruder and a 200 mm wide T-die was used to produce a film having a thickness of 90 μm at a resin temperature of 200° C. and a take-up speed of 5 m/min. Molding was carried out without any particular problems. The resulting film had good appearance and transparency. From this result, it was confirmed that the resin composition of the present invention can be melt-molded.

(Examples 2 to 20)
A resin composition was produced in the same manner as in Example 1 except that the formulations shown in Table 2 were used. Table 3 shows the evaluation results of the resin composition.
In addition, the ethylene-maleic anhydride-methyl acrylate used as the raw material resin has an MFR of 9 g/10 min, a maleic anhydride structure content of 1.3% by mass, and a methyl acrylate structure content of 13% by mass. Table 1 shows the composition of the terpolymer B and the physical property values in solid viscoelasticity measurement.

(Comparative Examples 1 to 15)
A resin composition was produced in the same manner as in Example 1 except that the formulations shown in Table 2 were used. Table 3 shows the evaluation results of the resin composition.
In addition, the ethylene-maleic anhydride-methyl acrylate used as the raw material resin has an MFR of 31 g/10 min, a maleic anhydride structure content of 0.05% by mass, and a methyl acrylate structure content of 15% by mass. Table 1 shows the composition of the terpolymer C and the physical property values in solid viscoelasticity measurement.

The resin compositions described in Examples 1 to 20 satisfy the requirements of the present invention and have crosslinked structures having heat resistance close to that of resin compositions using metal ions, although they are free of metal ions. Also, depending on the type of reaction accelerator, it has a crosslinked structure with heat resistance equal to or higher than that of a resin composition using metal ions, excellent molding properties, and molded products are advantageous from the viewpoint of environmental compatibility. .
On the other hand, the resin compositions of Comparative Examples 1 to 8 have storage elastic modulus G′ at 130° C. and elastic retention temperature which are almost the same as those of the raw material resin, and it can be judged that a crosslinked structure cannot be formed. The organic amine compound added as a reaction accelerator does not function as a reaction accelerator.
The resin compositions of Comparative Examples 9 to 12 have no problem in terms of physical performance, but metal ions are used to realize the performance, and the molded products are inferior from the viewpoint of environmental compatibility.
The resin composition of Comparative Example 13 has a low elastic retention temperature due to a small molar ratio of hydroxyl groups to the acid anhydride, and the resin composition of Comparative Example 14 has a low elastic retention temperature due to a small amount of the reaction accelerator. Resin composition No. 15 has a low elastic retention temperature due to a low component concentration of the carboxylic anhydride structure in component (a), and it can be determined that no crosslinked structure is formed in any of the resin compositions.

As is clear from the above, although the resin composition of the present invention is metal ion-free, it has a crosslinked structure having heat resistance close to that of a resin composition using metal ions, and also has a reaction accelerator. Depending on the type, it has a cross-linked structure with heat resistance equal to or higher than that of a resin composition using metal ions, and it is possible to provide molded products that are advantageous in terms of environmental compatibility because they have excellent moldability. The industrial value of the resin composition and molded article of the invention is extremely high.

Claims (3)

A resin composition containing the following component (a), component (b) and component (c),
The component (a) is a polyolefin having at least one carboxylic anhydride structure, and the concentration of the carboxylic anhydride structure in the polyolefin is 0.1 to 20% by mass,
The component (b) is a polyhydric alcohol compound having at least two hydroxyl groups in the molecule,
The component (c) is a reaction accelerator that is a compound represented by the following general formula (3) ,
The molar ratio of the hydroxyl group unit in the polyhydric alcohol compound as the component (b) to the unit derived from the carboxylic anhydride structure in the polyolefin as the component (a) is 0.01 to 10. is in the range of
The reaction accelerator that is the component (c) is contained in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the polyolefin that is the component (a) ,
The polyolefin has at least one carboxylic anhydride structure and is a single weight of an olefin selected from the group consisting of ethylene, propylene, 1-butene, 1-hexene, and 4-methyl-1-pentene. Coalescence, or random or block copolymers of two or more of these olefins, or vinyl acetate, acrylic acid, methacrylic acid, acrylic acid esters, and methacrylic acid esters based on these olefins A resin composition comprising, as polyolefins, a binary or multi-component copolymer with at least one selected from the group consisting of :
General formula (3): R ¹ -N=C(-NR ² R ³ )-R ⁴
In the above general formula (3),
R ¹ is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group is R ³ and may be combined to form a ring structure, the ring structure may form a heterocyclic structure,
R ² is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group is R ⁴ and may be combined to form a ring structure, the ring structure may form a heterocyclic ring structure,
R ³ is a group selected from a hydrocarbon group having 1 to 10 carbon atoms and a hydrocarbon group having 1 to 10 carbon atoms having a substituent, and the hydrocarbon group is bonded to R ¹ may form a ring structure, the ring structure may form a heterocyclic structure,
R ⁴ is a group selected from a hydrogen atom, a halogen group, an ester group, a nitro group, a cyano group, a hydrocarbon group having 1 to 10 carbon atoms, and a hydrocarbon group having 1 to 10 carbon atoms having a substituent; and the hydrocarbon group may combine with R ² to form a ring structure, or the ring structure may form a heterocyclic ring structure. 2. The reaction accelerator according to claim 1 , which is at least one compound selected from the group consisting of imidazole compounds, benzimidazole compounds, diazabicyclononene compounds, diazabicycloundecene compounds, and imidazoline compounds. Resin composition. 3. A method for producing a thermoreversibly crosslinkable molded article, which comprises melt-molding the resin composition according to claim 1 or 2 , and forming a crosslinked structure in the cooling process.