JPH0616770A - Cross-linkable resin composition and production of cross-linked resin therefrom - Google Patents

Abstract

PURPOSE:To provide a cross-linkable resin composition excellent in preservability at normal temperatures, readily cross-linkable on heating, comprising an ethylene-based copolymer, blocked isocyanate and protected isocyanate at specified proportion. CONSTITUTION:The crosslinkable resin composition comprising (A) an ethylene- based copolymer produced from (1) ethylene, (2) at a copolymerization rate of 1.0-2.0wt.%, a hydroxyl group-contg. polymerizable compound having OH groups capable of binding to the C-atoms other than those each carrying polymerizable unsaturated bond, and (3) a polymerizable ester compound and/or polymerizable ether compound at a copolymerization rate of 21-60wt.% when totaled for the compound (2) and (B) a blocked isocyanate having in one molecule at least two protected isocyanate groups, and (C) 0.2-10mol, based on a total of 100mol of the monomer units for the component A, of a protected isocyanate. The other objective cross-linked resin can be obtained by heating this composition at a temperature not higher than the dissociation temperature of the isocyanate group plus 30 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a crosslinkable resin composition useful as a molding material and a physical property such as tensile strength, heat resistance, solvent resistance, weather resistance, permanent elongation, low temperature characteristics, etc., using the composition. And a method for producing a crosslinked resin excellent in heat resistance.

[0002]

2. Description of the Related Art Ethylene / acrylic acid ester copolymer rubber has been proposed as a composition having excellent properties such as heat resistance and weather resistance (for example, JP-A-58-11181).
4 publication). Since this composition has a carboxyl group as a crosslinking site, it can be amine-crosslinked or ionic-crosslinked. However, in order to exert the heat resistance that is the rubber characteristic, it is necessary to carry out crosslinking with a diamine or polyamine, but an uncrosslinked composition obtained by kneading a diamine or polyamine into this rubber does not react even at room temperature. It has the drawback of lacking storage stability because it is prone to occur. Further, in the case of amine cross-linking, it is complicated to select the type of amine and other compounding agents (for example, a cross-linking aid) and to determine the mixing and cross-linking conditions in order to obtain an appropriate cross-linked product.

Further, JP-B-50-116525 discloses a saponified product of ethylene / vinyl acetate copolymer (hereinafter sometimes abbreviated as EVA), which is an unsaturated compound containing an unsaturated carboxyl group or a cyclic acid anhydride. A composition consisting of an acid-modified product obtained by reacting a polyisocyanate with a polyisocyanate compound has been proposed, but this is a heat-resistant adhesive composition, and EVA must be saponified. Further, it has a drawback that carbon dioxide gas generated during the reaction between the acid component and the isocyanate compound remains as fine bubbles inside the molded body. In addition, Japanese Examined Japanese Patent Publication Sho 61-8
In 7719, a curable resin composition of a copolymer of aminoalkyl acrylate or methacrylate and an ethylenically unsaturated monomer and a blocked isocyanate is proposed, which is useful as a baking type paint or an adhesive. Since it is a composition, it has disadvantages such as poor flexibility and permanent elongation, and generally difficult molding in the rubber industry and the polyolefin industry.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and provides a crosslinkable resin composition which is excellent in storage stability at room temperature, causes a crosslinking reaction by heating, and does not generate a gas at that time. In addition, it is an object of the present invention to provide a method for producing a crosslinked resin which is excellent in physical properties such as tensile strength, heat resistance, solvent resistance, weather resistance, oil resistance, permanent elongation and low temperature characteristics using the composition.

The present invention achieves the above object by blending a block isocyanate with an ethylene-based copolymer of ethylene, a hydroxyl group-containing monomer and another polar group-containing monomer, and crosslinking with a urethane bond. That is, in the present invention, the copolymerization ratio of (A) ethylene is 1.0 to 1.0.
20% by weight is composed of a hydroxyl group-containing polymerizable compound having an OH group bonded to a carbon other than the polymerizable unsaturated bond carbon and an ester polymerizable compound and / or an ether polymerizable compound. And / or an ethylene-based copolymer having a copolymerization ratio of the ether-based polymerizable compound of 21 to 60% by weight in total with the hydroxyl-containing polymerizable compound and (B) a protected isocyanate group in at least one molecule. A crosslinkable resin containing 2 blocked isocyanates and 0.2 to 10 mol of protected isocyanate groups per 100 mol of the total of the monomer units constituting the ethylene copolymer. The composition is provided with the crosslinkable resin composition at a temperature not lower than the dissociation temperature of the protected isocyanate group contained in the composition, 300 ° C or higher. There is provided a method for manufacturing a crosslinked resin, which comprises heating at a temperature below.

The crosslinkable resin composition of the present invention contains the ethylene copolymer (A) and the blocked isocyanate (B) as described above, but the ethylene copolymer which is the component (A). Is obtained by radically polymerizing ethylene and a hydroxyl group-containing polymerizable compound having an OH group bonded to a carbon other than the polymerizable unsaturated bond carbon and an ester polymerizable compound and / or an ether polymerizable compound under high pressure. It is a copolymer that is used. Here, as the hydroxyl group-containing polymerizable compound having an OH group bonded to carbon other than the polymerizable unsaturated bond carbon, hydroxyalkyl (meth) acrylate [(meth) acrylate means methacrylate and acrylate. The same shall apply hereinafter], hydroxyalkylalkoxy (meth) acrylate, hydroxyalkyldialkoxy (meth) acrylate, hydroxyalkylpolyalkoxy (meth) acrylate, hydroxyalkylvinylether, hydroxyalkylalkoxyvinylether, hydroxyalkyldialkoxyvinylether, hydroxyalkylpolyalkoxyvinylether And so on. More specifically, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethylethoxy (meth) acrylate, dipropylene glycol mono (meth). Examples thereof include acrylate, 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, and allyl alcohol.

The ethylene-based copolymer used in the present invention contains 1.0 to 20 hydroxyl group-containing polymerizable compounds as described above.
It must be copolymerized by weight percent. When the copolymerization ratio of the hydroxyl group-containing polymerizable compound is less than 1.0% by weight, the crosslinking with the blocked isocyanate is insufficient,
The heat resistance and weather resistance are deteriorated, and the effect of the present invention does not change even if it exceeds 20% by weight.

The ethylene-based copolymer used in the present invention further comprises, as constituent monomers, one or more of an ester-based polymerizable compound and an ether-based polymerizable compound (hereinafter, these may be referred to as a third comonomer). Contains. Here, examples of the ester-based polymerizable compound include vinyl acetate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, lauryl acrylate, benzyl acrylate, and acrylic acid. N, N-dimethylaminoethyl, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, fumaric acid Examples include dibutyl, dimethyl maleate, diethyl maleate, dipropyl maleate, dibutyl maleate and the like. Examples of the ether-based polymerizable compound include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether,
Examples include octadecyl vinyl ether and phenyl vinyl ether.

The copolymerization ratio of the third comonomer is such that the total amount with the hydroxyl group-containing polymerizable compound is 21 to 60% by weight, preferably 25 to 60% by weight. This total amount is 21% by weight
If it is less than the target rubber properties are insufficient,
If it exceeds 60% by weight, the properties of the rubber are satisfied, but it is not necessary in terms of production and cost.

The ethylene copolymer used in the resin composition of the present invention is a composition prepared by blending ethylene, a hydroxyl group-containing polymerizable compound and a third comonomer so as to have the above composition at 700 to 3000 atm, preferably 1000 atm. ~ 2500
100 to 300 ° C., preferably 150 to 270 at atmospheric pressure
It is obtained by polymerizing in the presence of a radical initiator at ℃ (average temperature in the reactor). If the pressure is less than 700 atm, the molecular weight of the polymer cannot be increased, the moldability is deteriorated, and the polymer having sufficient physical properties cannot be obtained. On the other hand, a pressure exceeding 3000 atm is substantially meaningless and only increases the manufacturing cost. Further, if the temperature is lower than 100 ° C, the reaction is not stable and the conversion rate to the polymer is lowered, which is economically problematic. If the temperature is higher than 300 ° C, the molecular weight of the polymer cannot be increased and a runaway reaction may occur. Danger occurs. At the time of production, basically, ordinary low-density polyethylene production equipment and technology can be used. As a reactor type, an autoclave with a stirrer or a tubular type can be used, and if necessary, a plurality of reactors can be connected in series or in parallel to carry out multistage polymerization. Further, in the case of an autoclave type reactor, by partitioning the inside of the reactor into a plurality of zones, it is possible to provide a temperature distribution and more strictly control the temperature. Upon polymerization, ethylene, a hydroxyl group-containing polymerizable compound and a third comonomer are compressed and fed into a reactor,
Polymerization is performed by utilizing the separately injected radical initiator. The hydroxyl group-containing polymerizable compound and the third comonomer may be diluted with a solvent and used for handling reasons.

As a solvent, water; hexane, heptane, octane, decane, petroleum ether, cyclohexane, benzene, toluene, xylene, ethylbenzene, dodecylbenzene, tetralin, turpentine, and other hydrocarbons; ethyl ether, isopropyl ether, methylphenyl ether , Ethers such as ethylbenzyl ether, dioxane, furan, tetrahydrofuran, diethyl acetal; ketones such as acetone, methyl acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, ethyl butyl ketone, diisopropyl ketone acetonyl acetone, mesityl oxide, cyclohexanone Kinds; methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl Alcohols, alcohols such as t-butyl alcohol and octyl alcohol; methyl formate, ethyl formate, isobutyl formate, amyl formate, methyl acetate, ethyl acetate, isobutyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, ethyl propionate, isoamyl propionate. , Ethyl butyrate, isoamyl butyrate,
Esters such as methyl acetoacetate, isoamyl isovalerate, methyl lactate, isoamyl lactate, ethyl benzoate, dimethyl oxalate, diethyl oxalate, dibutyl oxalate, diethyl malonate, dimethyl phthalate, dibutyl phthalate, dibutyl tartrate; Acids such as acetic acid; carbon disulfide, dimethyl sulfoxide, propane sultone, triethyl phosphate, triphenyl phosphate and the like. These solvents can be used in combination of two or more, if necessary.

The radical initiator is not particularly limited as long as it is a compound capable of generating a radical, and for example, di-t-
Dialkyl peroxides such as butyl peroxide, dicumyl peroxide and t-butyl cumyl peroxide; diacyl peroxides such as acetyl peroxide, i-butyl peroxide and octanoyl peroxide; di i-propyl peroxydicarbonate , Peroxydicarbonates such as di2-ethylhexylperoxydicarbonate; peroxyesters such as t-butylperoxypivalate and t-butylperoxylaurate; methylethylketone peroxide, 1,1-bis-t-butylperoxide Peroxyketals such as oxycyclohexane and 2,2-bis-t-butylperoxyoctanone; organic peroxides such as t-butyl hydroperoxide, cumene hydroperoxide and other hydroperoxides, and others 2.
Examples thereof include azo compounds such as 2-azobisisobutyronitrile and oxygen.

In addition, various chain transfer agents can be used as a molecular weight regulator in the polymerization. Examples of the chain transfer agent include olefins such as propylene, butene and hexene; paraffins such as ethane, propane and butane; carbonyl compounds such as acetone, methyl ethyl ketone and methyl acetate; aromatic hydrocarbons such as toluene, xylene and ethylbenzene. Kind of things can be mentioned.

The copolymer obtained as described above is discharged from the reactor together with the unreacted monomer, and the high pressure separator,
In some cases, the polymer and the monomer or the low molecular weight polymer are separated through a medium pressure separator or a low pressure separator, and then pelletized through a kneader or a veil or an extruder, while the unreacted monomer has a low molecular weight. The polymer is filtered off and then recycled for reuse. Additives such as those described below can also be added in the case of pelletization or pelletization. The ethylene copolymer thus obtained has MFR
(190 ° C., load 2.16 kg, JIS-K7210) usually 0.1 to 1000 (g / 10 minutes) is used. When this MFR exceeds 1000 (g / 10 minutes),
When the finally obtained ethylene-based copolymer is mixed with the blocked isocyanate, it becomes difficult to mix it uniformly, and the appearance, moldability and mechanical strength of the obtained composition are deteriorated. The preferred MFR range is 0.3-30
It is 0 (g / 10 minutes). Further, it is also possible to use a copolymer obtained by grafting ethylene and a third comonomer at 21% by weight or more and a hydroxyl group-containing polymerizable compound at 1.0% by weight or more on the copolymer obtained under high pressure.

The resin composition of the present invention further contains a blocked isocyanate having at least two protected isocyanate groups in one molecule (hereinafter, abbreviated as blocked isocyanate). That is, the blocked isocyanate is a compound having a protected isocyanate group obtained by reacting an isocyanate group and a protective agent by a conventional method, the protected isocyanate group at a specific temperature according to the protective group It is thermally dissociated by heating to remove the protective agent and regenerate the isocyanate group. The blocked isocyanate used in the present invention is a compound having at least two such isocyanate groups in one molecule, but one having two to three is preferable. Such a blocked isocyanate is obtained by reacting a polyisocyanate with a protective agent.

Typical polyisocyanates are reaction products of an excess amount of aromatic, aliphatic or alicyclic diisocyanate, triisocyanate and diisocyanate with polyisocyanate having a molecular weight of 60 to 2000 as a chain extender. Is mentioned. Here, as typical examples of diisocyanates, alkylene diisocyanates such as ethylene diisocyanate, tetramethylene diisocyanate and hexamethylene diisocyanate; tolylene diisocyanate, metaphenylene diisocyanate,
Aromatic diisocyanates such as diphenylmethane diisocyanate; 4 ′, 4-methylene-bis (cyclohexyl isocyanate), ω, ω-diisocyanate-1,4
Alicyclic diisocyanates such as dimethylcyclohexane and isophorone diisocyanate. Further, as a typical example of triisocyanate, a trimer of diisocyanate, for example, a trimer of tolylene diisocyanate,
Hexamethylene diisocyanate trimer etc. are mentioned.

A typical example of the polyisocyanate using the chain extender is a reaction product of the above-mentioned excess amount of diisocyanate and a polyol having a molecular weight of 60 to 2,000. Examples of the polyol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetramethylene glycol, hexamethylene glycol, trimethylolpropane, pentaerythritol and the like.

In the present invention, 2 mol of the above-mentioned diisocyanate and 1 of the above-mentioned diol are used as the diisocyanate component.
It is advantageous to use the blocked isocyanates obtained by reacting with mols, which are further reacted with protecting agents. This blocked isocyanate is represented by the following general formula (I).

[0019]

[Chemical 1]

[In the formula, Bl represents a residue of an isocyanate protecting agent, R ¹ represents a residue of a divalent isocyanate,
It represents a hydrocarbon group having 2 to 20 carbon atoms, R ² represents a hydrogen atom or a methyl group, m represents an integer of 1 to 5, and n represents 1 to 1.
Represents an integer of 30. ]

The diisocyanate which is the starting material for the blocked isocyanate represented by the general formula (I) includes tolylene diisocyanate, diphenylene diisocyanate, 4,4'-methylene-bis (cyclohexyl isocyanate) and isophorone diisocyanate among the above diisocyanates. Is preferred, and isophorone diisocyanate is more preferred. Among the above-mentioned diols, ethylene glycol, diethylene glycol, propylene glycol and tetramethylene glycol are preferable as the starting material for the blocked isocyanate represented by the general formula (I).

In the general formula (I), Bl is a residue of a protecting agent, which is a group obtained by removing a hydrogen atom from the protecting agent. As the protective agent, any of phenol type, lactam type, active methylene type, acid amide type, imide type, amine type, imidazole type, urea type, imine type and oxime type can be used. Of these, phenol-based, lactam-based, acid amide-based, active methylene-based and oxime-based protective agents are preferable, and lactam-based protective agents are more preferable. Here, examples of the phenol-based protective agent include monohydric phenols such as phenol, cresol, xylenol, ethylphenol, and nonylphenol. As a lactam-based protective agent, β-
Propiolactam, γ-butyrolactam, δ-valerolactam, ε-caprolactam and the like are preferable. Examples of the acid amide-based protective agent include monocarboxylic acid amides such as acetanilide, acetic acid amide, stearic acid amide. Examples of the active methylene-based protecting agent include dialkyl malonate, alkyl acetoacetate (the alkyl is preferably a methyl group or an ethyl group), acetylacetone and the like. Furthermore, as the oxime-based protective agent,
Formaldoxime, acetoaldoxime, methyl ethyl ketone oxime, cyclohexanone oxime and the like can be mentioned. The protective agent is liberated in the composition at a temperature equal to or higher than the dissociation temperature, but it is preferable that the protective agent does not impair the appearance of the molded product such as foaming of a crosslinked product.

In the present invention, the block isocyanate may be used alone or in combination of two or more kinds.
For example, the blocked isocyanate represented by the general formula (I) can be used in combination with the other blocked isocyanate. In this case, the proportion of the blocked isocyanate represented by the general formula (I) in all the blocked isocyanates is 10 mol% or more, preferably 20 mol% or more, more preferably 50 mol% or more. The presence of the blocked isocyanate represented by the general formula (I) is extremely important for imparting a physical property balance to the crosslinked product. The function of the blocked isocyanate of the general formula (I) is not always clear in order to maintain appropriate flexibility, ensure elongation, and increase breaking strength.

The crosslinkable resin composition of the present invention is produced by mixing the above-mentioned (A) ethylene copolymer and (B) blocked isocyanate, and the mixing ratio of both components is ethylene. It is limited by the relationship between the total number of moles of the constituent monomer units of the system copolymer and the number of moles of the protected isocyanate group in the blocked isocyanate. That is, the total of the constituent monomer units of the ethylene-based copolymer is 1
The number of moles of the protected isocyanate group in the block isocyanate is 0.2 to 10 moles, preferably 0.3 to 5 moles, relative to 00 moles, and the hydroxyl group in the constituent monomer of the ethylene copolymer. The number of moles of the protected isocyanate group per mole of the polymerizable compound unit is 0.0
It is preferably set to 2 to 2.5 mol. If the number of moles of the protected isocyanate group per mole of the hydroxyl group-containing polymerizable compound unit exceeds 2.5 moles, not only the crosslinking becomes incomplete, but also the strength and heat resistance of the obtained crosslinked product are not necessarily sufficient. It does not become.

To produce the crosslinkable resin composition of the present invention, the ethylene copolymer (A) and the blocked isocyanate (B) may be mixed by various means. As a mixing method, for example, they may be mixed in a solvent such as toluene, xylene, ethyl acetate, or methyl ethyl ketone.
Dry blending may be performed using a mixer such as a Henschel mixer or tumbler that is commonly used in the field of olefin polymers, and melting may be performed using a kneader such as a Banbury mixer, kneader, extruder, or roll mill. A method of kneading can be mentioned. At this time, a uniform mixture can be obtained by previously dry-blending and melt-kneading the resulting mixture. During melt-kneading, it is necessary that the ethylene copolymer and the blocked isocyanate do not substantially undergo a crosslinking reaction. In the unlikely event of crosslinking, not only the moldability will deteriorate when the resulting composition is molded and processed, but it will also cause deterioration in heat resistance and appearance when the desired shape of the molded product or the molded product is crosslinked. Not preferable. Therefore, the temperature of melt-kneading depends on the type of blocked isocyanate, particularly the type of protective agent, and is generally 80 to 140 ° C., preferably 90 ° C.
˜130 ° C., but importantly below the dissociation temperature of the blocked isocyanate. When kneading at a temperature exceeding the dissociation temperature, the ethylene copolymer and the blocked isocyanate are partially or entirely crosslinked, and the above problems occur.

Additives which are generally used in the field of olefin polymers for producing resin compositions, for example, stabilizers against oxygen, light (ultraviolet rays) and heat, antistatic agents, lubricants, nucleating agents, pigments. (Colorant), foaming agent, processing improver and the like can be added within a range that does not impair the properties of the crosslinked product of the present invention.

The resin composition of the present invention obtained as described above can be formed into a molded product by almost any existing molding method. For example, in the method of casting and heating the composition, a desired molded article can be obtained by heating and crosslinking by cast molding, compression molding, transfer molding, powder molding and the like. The crosslinking depends on the type of blocked isocyanate, but is usually 100 to 300 ° C, preferably 150 to 250 ° C. On the other hand, the higher the temperature, the shorter the cross-linking treatment is, but usually 100 to 20.
30 seconds to 60 minutes at 0 ° C., and 10 seconds to 30 minutes at 200 to 300 ° C. are preferable.

[0028]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Examples 1 to 15 and Comparative Examples 1 to 8 Polymerization was carried out at a temperature of 190 to 230 ° C. and a pressure of 18 in an autoclave type reactor divided into 2 zones with an internal capacity of 4 liters.
It was carried out using t-butylperoxypivalate as an initiator under the conditions of 00 to 1950 atm. The hydroxyl group-containing polymerizable compound or the compound and other monomer and / or solvent were injected upstream of the second-stage compressor and were supplied together with ethylene to the first zone of the reactor. The produced copolymer was separated from unreacted monomers by a high-pressure separator and a low-pressure separator, and was pelletized or pelletized by using an extruder to produce copolymers shown by A to H below. The hydroxyl group-containing polymerizable compound and the content of the third comonomer in each copolymer were measured by using an infrared spectrometer and ¹³ C-NMR, and MFR was measured according to JIS-
K7210 was measured at 190 ° C. under a load of 2.16 kg.

A. Ethylene / methyl acrylate / 2-hydroxyethyl methacrylate copolymer Methyl acrylate content 23.8% by weight, 2-hydroxyethyl methacrylate content 6.8% by weight, MFR22
(G / 10 minutes) B. Ethylene / ethyl acrylate / 2-hydroxyethyl acrylate copolymer Ethyl acrylate content 28% by weight, 2-hydroxyethyl acrylate content 9.5% by weight, MFR 38 (g /
10 minutes) C.I. Ethylene / methyl methacrylate / 2-hydroxyethyl acrylate copolymer Methyl methacrylate content 31% by weight, 2-hydroxyethyl acrylate content 3.8% by weight, MFR 68 (g
/ 10 minutes) D. Ethylene / methyl acrylate / 2-hydroxyethyl acrylate copolymer Methyl acrylate content 25.9% by weight, 2-hydroxyethyl acrylate content 14.2% by weight, MFR18
(G / 10 minutes) E. Ethylene / vinyl acetate / 2-hydroxyethyl methacrylate copolymer Vinyl acetate content 23.5% by weight, 2-hydroxyethyl methacrylate content 4.7% by weight, MFR46 (g / 1
0 minutes) F. Ethylene / butyl acrylate / 2-hydroxyethyl acrylate copolymer Butyl acrylate content 18.2% by weight, 2-hydroxyethyl acrylate content 16.1% by weight, MFR26
(G / 10 minutes) G.I. Ethylene / methyl methacrylate / 2-hydroxyethyl acrylate copolymer Methyl methacrylate content 32.6% by weight, 2-hydroxyethyl acrylate content 0.49% by weight, MFR52
(G / 10 minutes) Ethylene / methyl acrylate / 2-hydroxyethyl acrylate copolymer Methyl acrylate content 7.8% by weight, 2-hydroxyethyl acrylate content 7.2% by weight, MFR27 (g /
10 minutes)

The blocked isocyanate used is as follows. A blocked isocyanate having a 2: 1 adduct of isophorone diisocyanate and ethylene glycol protected with ε-caprolactam (hereinafter referred to as BIS-
It is abbreviated as A. A dissociation temperature of 160 ° C.), a blocked isocyanate in which a 2: 1 adduct of tolylene diisocyanate and diethylene glycol is protected with m-cresol (hereinafter abbreviated as BIS-B. Dissociation temperature of 160 ° C.),
Blocked isocyanate in which tolylene diisocyanate is protected with methyl ethyl ketone (hereinafter abbreviated as BIS-C. Dissociation temperature 130 ° C.) and 2: 1 adduct of isophorone diisocyanate and propylene glycol are mixed with ε.
-A blocked isocyanate protected with caprolactam (hereinafter abbreviated as BIS-D. Dissociation temperature 160 ° C) was used.

The ethylene copolymer shown in Table 1 and the blocked isocyanate were mixed in the mixing ratio shown in Table 1,
30 mmφ vent extruder (C ₁ 100 ° C, C ₂ 110
Pelletized at 120 ° C., C ₃ 120 ° C. and die 120 ° C.). At that time, 500 ppm (by weight) of 2,6-di-t-butyl-4-methylphenol was added as a stabilizer.

[0033]

[Table 1]

[0034]

[Table 2]

100 kg / c of the resin composition having the above composition
A sheet was manufactured by crosslinking under pressure of m ² (gauge pressure) at the temperature and time shown in Table 2 and compression molding. Regarding the obtained sheet, the tensile test (breaking strength and breaking elongation), Shore hardness A and permanent elongation were JIS-K63.
The heat resistance test was carried out at 170 ° C. for 100 hours, and the residual tensile elongation (elongation) was measured according to JIS.
-Measured according to K6301. The measurement results are shown in Table 3.

[0036]

[Table 3]

[0037]

[Table 4]

[0038]

[Table 5]

[0039]

EFFECTS OF THE INVENTION The crosslinkable resin composition according to the present invention has excellent storage stability at room temperature, is easily crosslinked by heating, and does not generate gas at that time. By heating and crosslinking this crosslinkable resin composition according to the method of the present invention, heat resistance, solvent resistance, weather resistance, ultraviolet resistance and ozone resistance are excellent, and rubber properties (for example, tensile strength and elongation rate) are obtained. , Permanent elongation) and hardness, as well as a crosslinked resin with excellent low temperature properties. Therefore, the crosslinkable resin composition according to the present invention is expected to be effectively used as a molding material for moldings having excellent various physical properties.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuaki Tsutsumi 2 Nakanosu, Oita City, Oita Prefecture Showa Denko Oita Factory

Claims (3)

[Claims] 1. A copolymerization ratio of (A) ethylene with 1.0 to 2
It is composed of a hydroxyl group-containing polymerizable compound having an OH group bonded to carbon other than 0% by weight of the polymerizable unsaturated bond carbon and an ester-based polymerizable compound and / or an ether-based polymerizable compound. And / or an ethylene-based copolymer having a copolymerization ratio of the ether-based polymerizable compound of 21 to 60% by weight in total with the hydroxyl-containing polymerizable compound and (B) a protected isocyanate group in at least one molecule. Containing two blocked isocyanates, the total amount of the monomer units constituting the ethylene-based copolymer is 100 mol, and the protected isocyanate group is
The crosslinkable resin composition is present in an amount of 0.2 to 10 mol. 2. The mole number of the protected isocyanate group is 0.02 to 2.5 moles per mole of the hydroxyl group-containing polymerizable compound unit in the constituent monomer of the ethylene copolymer. Crosslinkable resin composition. 3. The production of a crosslinked resin, which comprises heating the crosslinkable resin composition according to claim 1 at a temperature not lower than the dissociation temperature of protected isocyanate groups contained in the composition and not higher than 300 ° C. Method.