JP2000034376A - Olefin polymer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an olefin polymer composition having good crosslinkability and crosslink dissociation properties, excellent thermoreversible crosslinkability, and no bleed-out. A modified olefin polymer modified with the following components (A) and (B) (A) unsaturated carboxylic acid anhydride and unsaturated carboxylic acid ester, wherein the carboxylic acid anhydride per molecule is Olefin polymer (B) in which the average number of bond groups is one or more, and the ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups in the modified olefin polymer is 0.5 to 20 (B) It is composed of a hydroxyl group-containing polymer having an average number of hydroxyl groups of 1 or more per molecule, and the ratio of the number of hydroxyl groups of the component (B) to the number of carboxylic anhydride groups of the component (A) is from 0.1 to 0.1.
5. The reversible crosslinkable olefin polymer composition which is 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an olefin polymer composition, and more particularly, to a so-called thermoreversible crosslinkable olefin polymer which can repeatedly form crosslinks at low temperatures and dissociate crosslinks at high temperatures. It relates to a polymer composition.

[0002]

2. Description of the Related Art Olefinic resins such as polyethylene and polypropylene are excellent in moldability, mechanical strength, transparency, chemical resistance, etc., and are variously molded such as extrusion molding, injection molding, hollow molding, compression molding, and rotational molding. It is shaped into a desired shape in the molten state by the method and is widely used in various fields. Also, in order to impart heat resistance and improve mechanical strength at high temperatures, etc., compounding of organic peroxide, irradiation of radiation Alternatively, it is often used as a crosslinked body which has been subjected to a crosslinking treatment by utilizing a silanol condensation reaction or the like. On the other hand, from the standpoint of environmental protection and resource saving, it is becoming increasingly necessary to reuse used resins.However, this crosslinked resin is no longer thermoplastic. It cannot be reused by melt molding without it, and there is a strong demand for compatibility between this crosslinked product and thermoplasticity.

On the other hand, at low temperatures, crosslinks are formed,
In contrast to some conventional techniques as a method of dissociating the crosslinks at high temperature to impart thermoplasticity, an olefin resin composition having excellent thermoreversible crosslinkability, particularly high crosslink formation reaction rate and crosslink dissociation reaction rate JP-A-6-5
Nos. 7062 and 7-94029 disclose unsaturated carboxylic anhydride-modified olefin resins and polyhydric alcohol compounds having at least two hydroxyl groups in the molecule, for example, glycols such as ethylene glycol,
Alcohols such as 1,4-butanediol, sugars such as sorbitol, polyoxyalkylene compounds such as trimethylolpropane, polyglycerin alkyl esters such as diglycerin monostearate, sorbitan alkyl esters such as sorbitan monostearate An olefin resin composition comprising a polymer having a plurality of hydroxyl groups in a molecule such as an ethylene-hydroxyethyl acrylate copolymer and a reaction accelerator such as a metal salt of a carboxylic acid is disclosed.

According to studies by the present inventors, a thermoreversible crosslinkable composition based on the reaction between a carboxylic acid anhydride group and a hydroxyl group basically comprises one molecule of a carboxylic acid anhydride group. And one molecule of hydroxyl group reacts to form a carboxylic acid monoester, and one reaction of the generated carboxylic acid monoester and one molecule of hydroxyl group further reacts to form a carboxylic acid diester. The former carboxylic acid monoester formation reaction has good thermoreversibility, but the latter carboxylic acid diester formation reaction has poor heat reversibility, and further, in the above-mentioned prior art, acid anhydrides are used. Although the initial cross-linking degree is high because the metal salt formation reaction between the group and the organic carboxylic acid metal salt also occurs at the same time, the formation of the subsequent cross-links is extremely slow,
In addition, the metal salt formation reaction is easily dissociated at a high temperature, and since the ester formation reaction is reduced by the reaction, the degree of heat-resistant cross-linking is reduced as a whole. It has been found that there is a problem that the heat resistance of the composition is inferior, and when the polyhydric alcohol compound is excessive, bleed-out easily occurs in the composition.

[0005]

SUMMARY OF THE INVENTION Based on the results of the above-mentioned study on the prior art, the present inventors have achieved excellent crosslinking reaction rates and crosslinking dissociation reaction rates without using metal salts of organic carboxylic acids. As a result of intensive studies to obtain a thermoreversible crosslinkable olefin-based polymer composition, the present invention has been achieved.Therefore, the present invention provides high thermoreversible crosslinkability having high crosslinkability and crosslink dissociation. It is an object of the present invention to provide an olefin polymer composition having no bleed-out.

[0006]

Means for Solving the Problems The present inventors have formulated a specific modified olefin polymer modified with an unsaturated carboxylic anhydride and an unsaturated carboxylic acid ester with a specific hydroxyl group-containing polymer in a specific amount. The present invention has been accomplished by finding that the above-mentioned object can be attained by carrying out, that is, the present invention provides the following (A) and (B) components (A) unsaturated carboxylic anhydride and unsaturated carboxylic acid anhydride. A modified olefin polymer modified with a carboxylic acid ester, wherein the average number of carboxylic acid anhydride groups per molecule is one or more, and the carboxylic acid anhydride in the modified olefin polymer is A modified olefin polymer having a ratio of the number of carboxylic acid ester groups to the number of groups of 0.5 to 20 (B) a polymer comprising a hydroxyl group-containing polymer having an average number of hydroxyl groups of 1 or more per molecule; , 0.1 is ratio of the number of hydroxyl groups (A) (B) component to the carboxylic acid anhydride groups of components
5. The reversible crosslinkable olefin polymer composition which is 5.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The modified olefin polymer modified by the unsaturated carboxylic anhydride and the unsaturated carboxylic acid ester as the component (A) in the present invention basically includes an α-olefin and ethylene. Terpolymers of ethylenically unsaturated carboxylic acid anhydrides and ethylenically unsaturated carboxylic acid esters, and ternary copolymers of α-olefins and ethylenically unsaturated carboxylic acid anhydrides Graft with acid ester, graft with α-olefin and ethylenically unsaturated carboxylic acid ester with ethylenically unsaturated carboxylic anhydride, ethylenically unsaturated carboxylic acid with α-olefin polymer There is a graft with an anhydride and an ethylenically unsaturated carboxylic acid ester.

As the α-olefin in the former terpolymer, for example, ethylene, propylene, butene-
1,3-methylbutene-1, pentene-1,3-methylpentene-1,4-methylpentene-1, hexene-
1, octene-1, decene-1 and the like.

Examples of the ethylenically unsaturated carboxylic anhydride include 2-octen-1-yl succinate anhydride, 2-dodecene-1-yl succinate anhydride, and 2-octadecene-1-succinic anhydride. Yl anhydride, maleic anhydride, 2,3-dimethylmaleic anhydride, bromomaleic anhydride, dichloromaleic anhydride, citraconic anhydride, itaconic anhydride, 1-butene-3,4-dicarboxylic acid Acid anhydride, 1-cyclopentene-1,2-dicarboxylic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, exo-3,6 -Epoxy-1,2,3,6-tetrahydrophthalic anhydride, 5-norbornene-2,3-
Dicarboxylic anhydride, methyl-5-norbornene-2,
3-dicarboxylic anhydride, endo-bicyclo [2.
2.2] oct-5-ene-2,3-dicarboxylic anhydride, bicyclo [2.2.2] oct-7-ene-2,
3,5,6-tetracarboxylic anhydride and the like.

The ethylenically unsaturated carboxylic acid ester is preferably an ester of an alkyl group having about 1 to 20 carbon atoms, for example, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid Propyl,
Butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate,
Examples include stearyl (meth) acrylate and dimethyl maleate. Here, "(meth) acrylic acid" refers to acrylic acid and methacrylic acid.

The former ternary copolymer includes the α
-In addition to a terpolymer of an olefin, the ethylenically unsaturated carboxylic anhydride and the ethylenically unsaturated carboxylic acid ester, further, an ethylenically unsaturated carboxylic acid compound such as (meth) acrylic acid and maleic acid And ethylenically unsaturated ester compounds such as vinyl acetate, ethylenically unsaturated amide compounds such as (meth) acrylamide and N-methyl (meth) acrylamide, and other ethylenically unsaturated compounds such as styrene and (meth) acrylonitrile. It may be a quaternary or higher copolymerized copolymer. These copolymers can be produced by a conventionally known polymerization method such as bulk, solution, suspension and the like.

Also, a binary copolymer of an α-olefin and an ethylenically unsaturated carboxylic acid anhydride, and a binary copolymer of an α-olefin and an ethylenically unsaturated carboxylic acid ester in the latter graft product Examples of the same include the same α-olefin, ethylenically unsaturated carboxylic anhydride, and ethylenically unsaturated carboxylic acid ester as mentioned in the former terpolymer, and α-olefin in the latter graft. Examples of the olefin-based polymer include homopolymers of ethylene such as low-density / medium-density / high-density polyethylene (branched or linear), ethylene, propylene, butene-1, 3-methylbutene-1, and pentene. −
1,3-methylpentene-1,4-methylpentene-
Α- such as 1, hexene-1, octene-1, and decene-1
Ethylene resins such as copolymers with olefins, ethylene and vinyl esters such as vinyl acetate, copolymers with other monomers such as (meth) acrylic acid or their esters, propylene homopolymers, propylene And α-olefins such as ethylene, butene-1,3-methylbutene-1, pentene-1,3-methylpentene-1,4-methylpentene-1, hexene-1, octene-1, and decene-1 Copolymer, propylene, and other monomers such as diene compounds such as isoprene, 1,3-butadiene, 1,3-pentadiene, 1,4-hexadiene, 1,5-hexadiene, and 1,9-decadiene Examples thereof include propylene-based resins such as copolymers, and homopolymers and copolymers of α-olefins such as butene-1,4-methylpentene-1 and hexene-1.

The ethylenically unsaturated carboxylic acid ester and the ethylenically unsaturated carboxylic acid anhydride to be grafted are the same as those described in the above terpolymer. These grafts can be produced by a conventionally known grafting method such as melt-kneading, solution, or suspension.

The modified olefin polymer of the component (A) in the present invention includes a terpolymer of ethylene, maleic anhydride and an alkyl (meth) acrylate, and an α-olefin polymer. Is preferably a grafted product of maleic anhydride and an alkyl (meth) acrylate, particularly a terpolymer of ethylene, maleic anhydride, and methyl or ethyl (meth) acrylate. .

In the present invention, the modified olefin polymer as the component (A) has an unsaturated carboxylic anhydride unit content of 0.1% by weight or more, particularly 0.5% by weight or more. It is preferable that the average number of bonds as a carboxylic anhydride group per molecule of the modified olefin polymer, which is determined based on the number average molecular weight of the modified olefin polymer and the multiplier of this content, is one It is essential that the number is at least 1.5, and it is preferable that the number is 1.5 or more. Here, when the average number of bonds is less than 1, the crosslinkability of the composition is inferior.

In the present invention, the modified olefin polymer as the component (A) is a carboxylic acid derived from the unsaturated carboxylic acid ester with respect to the number of carboxylic acid anhydride groups derived from the unsaturated carboxylic acid anhydride. It is essential that the ratio of the number of ester groups is 0.5 to 20;
It is preferably from 5 to 15. If the ratio is less than the above range, the crosslink dissociation property of the composition is poor, while if it exceeds the range, the crosslinkability of the composition is poor.

The modified olefin polymer of the component (A) in the present invention has an average number of carboxylic acid anhydride groups per molecule and a ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups. As long as the above range is satisfied, the modified olefin polymer may be diluted with an unmodified olefin polymer.

In the present invention, the hydroxyl group of the component (B) which bonds with the carboxylic acid anhydride group of the unsaturated carboxylic anhydride and the unsaturated carboxylic acid ester-modified olefin polymer of the component (A) to form a crosslink. Examples of the containing polymer include ethylene- (meth) acrylate 2-hydroxyethyl copolymer, 2- (meth) acrylate 2-hydroxyethyl grafted polyethylene, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, and low molecular weight. Polyolefin polyols, polyalkylene ether glycols, polyoxyalkylene polyols, hydroxyl-terminated diene polymers and their hydrogenated products or adipates thereof, hydroxyl-terminated polycaprolactones, etc., and these have a number average molecular weight of 500 to 10,000 It is preferred that Among them, in the present invention, from the viewpoint of imparting flexibility to the composition, those having a crystallinity of 30% or less are preferable. Specifically, low molecular weight polyolefin polyols, polyalkylene ether glycols, Alkylene polyols, hydroxyl-terminated diene polymers and hydrogenated products thereof are preferred.

In the present invention, the hydroxyl group-containing polymer as the component (B) is obtained by calculating the number-average molecular weight of the hydroxyl group-containing polymer by the multiplier of the hydroxyl group content. It is essential that the average number of bonds is 1 or more, and preferably 1.5 or more. If the number of hydroxyl groups per molecule is less than one, the crosslinkability of the composition will be poor.

The hydroxyl group-containing polymer of the component (B) in the present invention is a polymer diluted with a hydroxyl group-free polymer as long as the average number of hydroxyl groups per molecule satisfies the above range. Is also good.

In the reversible crosslinkable olefin polymer composition of the present invention, the composition ratio of the modified olefin polymer (A) and the hydroxyl group-containing polymer (B) is as follows. (B) based on the number of carboxylic anhydride groups
It is essential that the ratio of the number of hydroxyl groups of the component is from 0.1 to 5, and preferably from 0.1 to 3. Here, if the ratio of the number of hydroxyl groups to the number of carboxylic acid anhydride groups is less than the above range, the crosslinkability of the composition will be inferior. In addition, the bleed-out property is poor, and in any case, the object of the present invention cannot be achieved.

In the present invention, the term "reversible crosslinkability" refers to crosslinkability, that is, the heat deformation rate at the time of crosslinking is 35% or less, and the crosslink dissociation property, that is, the heat deformation rate after the crosslink dissociation treatment is 65%.
The above properties are referred to. If these values are out of the above ranges, problems such as slow progress of cross-linking, or the difficulty of dissociation after cross-linking once occur. The more preferable range of the crosslinkability is 30% or less, the more preferable range is 20% or less, the more preferable range of the crosslink dissociation is 80% or more, and the more preferable range is 90% or more.

The reversible crosslinkable olefin polymer composition of the present invention basically comprises the above components (A) and (B), but as long as the effects of the present invention are not impaired,
(B) It may contain a component other than the component, and specifically, for example, various commonly used additives such as an antioxidant, an ultraviolet absorber, a nucleating agent, a neutralizing agent, a lubricant, An anti-blocking agent, a dispersant, a flow improver, a release agent, a flame retardant, a colorant, a filler, and the like can be added. on the other hand,
Conventional "reaction accelerators" such as metal salts of carboxylic acids
As described above, the composition of the present invention tends to inhibit reversible cross-linking, so that it is not desirable to add it.

The reversible crosslinkable olefin polymer composition of the present invention comprises the above components (A) and (B) as essential components,
A method of adding other optional components, uniformly mixing each component with a Henschel mixer, a ribbon blender, a V-type blender, etc., and then melt-kneading with a single or multi-screw extruder, a roll, a Banbury mixer, a kneader, a Brabender, etc. Alternatively, using a single-screw or multi-screw extruder, the component (A) or the component (A) and other optional components are supplied from the inlet of the extruder, and the component (B) and other optional components or the component (B) are extruded. It can be prepared by, for example, a method of feeding and melting and kneading in the middle of the machine.

The reversible crosslinkable olefin polymer composition of the present invention as described above can be molded by various molding methods commonly used for thermoplastic resins, such as injection molding, extrusion molding, hollow molding, compression molding, and rotational molding. Thus, a reversible crosslinked molded article can be obtained by shaping into a desired shape in a molten state, and when a used molded article is reused, etc., it is again formed into a desired shape in a molten state by a similar molding method. It can be shaped into a crosslinked molded article.

[0026]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the invention. In addition, the modified olefin polymer of the component (A) used in Examples and Comparative Examples,
The hydroxyl group-containing polymer of the component (B) and the metal salt of the carboxylic acid (component (C)) are as follows.

(A) Component A-1: ethylene-maleic anhydride-ethyl acrylate terpolymer (maleic anhydride unit content 2.5% by weight measured by infrared absorption spectrum, ethyl acrylate) The unit content is 12.5% by weight, the ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups is 4.9, the number average molecular weight measured by gel permeation chromatography is 19800, and the number average molecular weight and the maleic anhydride unit content are 4. average number of carboxylic acid anhydride groups per molecule of the modified olefin polymer determined based on the multiplier
0, "Bondane TX8030" manufactured by Sumitomo Chemical Co., Ltd.)

A-2: ethylene-maleic anhydride-ethyl acrylate terpolymer (maleic anhydride unit content: 2.4% by weight as measured by infrared absorption spectrum;
2. Ethyl acrylate unit content 7.5% by weight, ratio of the number of carboxylic ester groups to the number of carboxylic anhydride groups
1. Number average molecular weight of 19300 measured by gel permeation chromatography, average bond of carboxylic acid anhydride groups per molecule of modified olefin polymer determined based on the number average molecular weight and the multiplier of maleic anhydride unit content Number 4.7, "Bondane LX" manufactured by Sumitomo Chemical Co., Ltd.
4110 ")

A-3; terpolymer of ethylene-maleic anhydride-ethyl acrylate (maleic anhydride unit content: 1.5% by weight as measured by infrared absorption spectrum;
1. Ethyl acrylate unit content: 4.2% by weight, ratio of the number of carboxylic ester groups to the number of carboxylic anhydride groups
7. Number average molecular weight of 20,000 measured by gel permeation chromatography, average bond of carboxylic anhydride groups per molecule of modified olefin polymer determined based on a multiplier of number average molecular weight and maleic anhydride unit content 3.1 units, "Bondane FX" manufactured by Sumitomo Chemical Co., Ltd.
8000 ")

A-4: ethylene-maleic anhydride-ethyl acrylate terpolymer (maleic anhydride unit content: 2.0% by weight as measured by infrared absorption spectrum;
Ethyl acrylate unit content 24.0% by weight, ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups 1
1.8, a number average molecular weight of 15,300 measured by gel permeation chromatography, and a number of carboxylic acid anhydride groups per molecule of the modified olefin polymer determined based on a multiplier of the number average molecular weight and the maleic anhydride unit content Average bond number 3.1, "Bondane HX8140" manufactured by Sumitomo Chemical Co., Ltd.)

A-5: Ethylene-butene-1 copolymer (melt flow rate 9 g / 10 min, density 0.925 g)
/ Cm ³ , "Z-50MG" manufactured by Nippon Polychem Co., Ltd.) 2
0 parts by weight, ethylene-butene-1 copolymer (melt flow rate 18 g / 10 min, density 0.890 g / cm ³ ,
1.0 part by weight of maleic anhydride, 5.0 parts by weight of stearyl acrylate, 2,5-dimethyl-2,5-bis, based on 80 parts by weight of "Tuffmer A200090" manufactured by Mitsui Chemicals, Inc. After adding 0.1 part by weight of (tertiary butyl peroxy) hexane and uniformly mixing with a Henschel mixer, a twin-screw extruder (Ikegai Co., Ltd., PC
(M-30, D = 30 mm, L / D = 32), a melt grafting reaction was performed to obtain a modified olefin-based polymer of maleic anhydride of ethylene-butene-1 copolymer and stearyl acrylate. The extruder was C ₁ : 150 ° C.
_{C 2: 190 ℃, C 3} ~D: 230 ℃, Ns: 200r
pm, Q: Operated under the conditions of 10 kg / Hr. The resulting modified olefin polymer has a melt flow rate of 13
g / 10 minutes, after reprecipitation purification treatment to remove ungrafted matter, a maleic anhydride unit content of 0.8% by weight, a stearyl acrylate unit content of 2.0% by weight, measured by infrared absorption spectrum, Ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups 0.76, number average molecular weight 5 measured by gel permeation chromatography
3000, the average number of carboxylic acid anhydride groups per molecule of the modified olefin polymer was 4.3, which was determined based on the multiplier of the number average molecular weight and the maleic anhydride unit content.

A-6 (for Comparative Example); ethylene-maleic anhydride-ethyl acrylate terpolymer (maleic anhydride unit content 0.8% by weight measured by infrared absorption spectrum, acrylic acid Ethyl unit content 30.0% by weight, ratio of the number of carboxylic acid ester groups to the number of carboxylic anhydride groups 36.7, number average molecular weight 18700 measured by gel permeation chromatography, number average molecular weight and maleic anhydride unit content The average number of carboxylic acid anhydride groups per molecule of the modified olefin-based polymer determined based on the multiplier of 1.5 is "Bondane AX8390" manufactured by Sumitomo Chemical Co., Ltd.)

A-7 (for comparative example); ethylene-butene-
1 copolymer (melt flow rate 9 g / 10 min, density 0.925 g / cm ³ , Nippon Polychem Co., Ltd. “Z-5”
0MG "), 100 parts by weight of maleic anhydride, 0.06 parts by weight of 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane are uniformly mixed with a Henschel mixer. Graft grafting with a twin-screw extruder (PCM-30, D = 30 mm, L / D = 32, manufactured by Ikegai Co., Ltd.), and modified ethylene-butene-1 copolymer with maleic anhydride A polymer was obtained. Incidentally, the extruder _{C 1: 150 ℃, C 2} : 190 ℃, C
_{3 to} D: 230 ° C, Ns: 200 rpm, Q: 10 kg
/ Hr. The resulting modified olefin polymer was subjected to reprecipitation purification at a melt flow rate of 2.0 g / 10 minutes to remove ungrafted products, and then had a maleic anhydride unit content of 0.1 as measured by an infrared absorption spectrum.
8% by weight, a number average molecular weight of 26,000 measured by gel permeation chromatography, and a number of carboxylic acid anhydride groups per molecule of the modified olefin polymer determined based on a multiplier of the number average molecular weight and the maleic anhydride unit content. The average number of bonds was 2.1.

(B) Component B-1: Hydrogenated product of hydroxyl-terminated polybutadiene (hydroxyl content 2.0% by weight, number-average molecular weight 1000, hydroxyl-containing weight determined based on a multiplier of number-average molecular weight and hydroxyl content) Average number of hydroxyl groups bonded per molecule of 1.6,
Crystallinity 0%, “Nissau PB GI-1” manufactured by Nippon Soda Co., Ltd.
000 ") B-2; Hydrogenated hydroxyl-terminated polybutadiene (hydroxyl group content: 1.5% by weight, number average molecular weight: 2000, per hydroxyl group-containing polymer molecule determined based on a multiplier of the number average molecular weight and the hydroxyl group content) The average bond number of the hydroxyl group is 1.7,
Crystallinity 0%, "Nissau PB GI-2" manufactured by Nippon Soda Co., Ltd.
000 ")

B-3: Hydrogenated product of hydroxyl-terminated polybutadiene (having a hydroxyl content of 0.9% by weight and a number average molecular weight of 30)
The average number of hydroxyl groups per molecule of a hydroxyl-containing polymer, determined based on the multiplier of the number-average molecular weight and the hydroxyl group content, is 1.6, the degree of crystallinity is 0%, "Nisso P" manufactured by Nippon Soda Co., Ltd.
B GI-3000 ”) B-4; low molecular weight polyolefin polyol (hydroxyl content 1.4% by weight, number average molecular weight 2,000, per hydroxyl group-containing polymer molecule determined based on a multiplier of the number average molecular weight and the hydroxyl group content) (Average number of hydroxyl groups: 1.7, crystallinity: 0%, "Polytail HA" manufactured by Mitsubishi Chemical Corporation)

B-5: 2-hydroxyethyl methacrylate-grafted ethylene-butene-1 copolymer (2-hydroxyethyl methacrylate unit content 0.8% by weight, number average molecular weight 2050, measured by infrared absorption spectrum)
0, hydroxyl-containing polymer 1 determined based on a multiplier of the number average molecular weight and the content of 2-hydroxyethyl methacrylate unit
Average number of hydroxyl groups per molecule: 1.3, crystallinity: 6
5.6%) B-6 (for comparative example); hydrogenated polybutadiene (hydroxyl content: 0% by weight, number average molecular weight: 1000, crystallinity: 0%, “Nissau PB BI-100” manufactured by Nippon Soda Co., Ltd.)
0 ")

Component (C) (for comparative example: metal carboxylate)
S) C-1; dilaurate Shibuchiru tin C-2; zinc acetate dihydrate C-3; cerium acetate (III) - hydrate C-4; Calcium stearate

<Examples 1 to 9 and Comparative Examples 1 to 9> The components (A) and (B) and further the components (C) shown in Table 1 were used in the composition ratios shown in Table 1, Using a lavender plastmill (manufactured by Toyo Seiki Co., Ltd.), 180 ° C, 5
The mixture was melt-kneaded at 0 rpm for 10 minutes to prepare an olefin polymer composition. The obtained composition was evaluated for crosslinkability, crosslink dissociation, flexibility, and bleed-out by the following methods. The results are shown in Table 1.

Example 10 A twin-screw kneader ("TEX-30" manufactured by Nippon Steel Works) was used as the component (A) and the component (B) at the composition ratios shown in Table 1.
First, the component (A) is melt-kneaded at a cylinder temperature of 200 ° C. and a screw rotation speed of 200 rpm, and the component (B) is charged in the middle of the kneader to melt-knead the two components, whereby the olefin polymer composition is obtained. Prepared. The obtained composition was evaluated for crosslinkability, crosslink dissociation, flexibility, and bleed-out by the following methods. The results are shown in Table 1.

Crosslinkability A 1 mm-thick press molding test prepared by preheating at 230 ° C. for 5 minutes, then heating under a pressure of 100 kg / cm ² for 5 minutes, and cooling under a pressure of 120 kg / cm ^2. After heat-treating the piece at 80 ° C. for 24 hours to crosslink,
140 in accordance with JIS C3005 (Heating deformation)
The heating deformation rate was measured under the conditions of 1 ° C. and 1 kgf.

Cross-linking and dissociation property A 1-mm-thick press-forming test produced by preheating at 230 ° C. for 5 minutes, heating under a pressure of 100 kg / cm ² for 5 minutes, and cooling under a pressure of 120 kg / cm ^2. After heat-treating the piece at 80 ° C. for 24 hours to crosslink,
After preheating again at 230 ° C. for 5 minutes, 100 kg / c
After heating under a pressure of m ² for 5 minutes and cooling under a pressure of 120 kg / cm ² , the heating deformation rate was measured at 140 ° C. and 1 kgf in accordance with JIS C3005 (heating deformation).

Flexibility A hardness was measured according to JIS K6301. Bleed-out property After preheating at 230 ° C. for 5 minutes, a press-formed test piece having a thickness of 1 mm produced by heating under a pressure of 100 kg / cm ² for 5 minutes and cooling under a pressure of 120 kg / cm ² , Heat treatment at 80 ° C. for 24 hours to crosslink, 23
After standing at 96 ° C. for 96 hours, a clean CaF ₂ plate was pressed on the surface at 23 ° C. at a pressure of 100 g / cm ² for 5 minutes.
The infrared absorption spectrum of the CaF ₂ plate was measured, and the absorbance A ₂₉₂₀ at ₂₉₂₀ cm ^{−1 at which} the CH asymmetric stretching vibration peak of the methylene group appeared was determined (the difference from the infrared absorption spectrum of the CaF ₂ plate measured in advance as a background). ), This was considered the bleed-out amount.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

According to the present invention, a reversible crosslinkable olefin polymer composition having good crosslinkability and crosslink dissociation properties, excellent thermoreversible crosslinkability, and no bleed-out can be provided. Therefore, the reversible crosslinkable olefin polymer composition of the present invention can be formed into a desired shape in a molten state by a molding method generally used for a thermoplastic resin to form a reversible crosslinked molded article. Even when the reversibly crosslinked molded article is reused or the like, the reversible crosslinked molded article can be obtained again by reshaping into a desired shape in a molten state by the same molding method.

Claims (4)

[Claims] 1. A modified olefin polymer modified by the following components (A) and (B): (A) an unsaturated carboxylic anhydride and an unsaturated carboxylic acid ester, wherein the carboxylic acid per molecule is A modified olefin polymer having an average bond number of one or more anhydride groups and a ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups in the modified olefin polymer of 0.5 to 20 (B A) a polymer comprising a hydroxyl group-containing polymer having an average number of hydroxyl groups of 1 or more per molecule, wherein the ratio of the number of hydroxyl groups of component (B) to the number of carboxylic anhydride groups of component (A) is 0.1 to
5. A reversible crosslinkable olefin polymer composition, which is 5. 2. The reversibly crosslinkable olefin polymer composition according to claim 1, wherein the modified olefin polymer as the component (A) is an ethylene-maleic anhydride-alkyl (meth) acrylate copolymer. object. 3. The modified olefin polymer of component (A) has an average number of carboxylic anhydride groups per molecule of 1.
5 or more and one of the hydroxyl group-containing polymers of the component (B)
The reversible crosslinkable olefin polymer composition according to claim 1 or 2, wherein the average number of hydroxyl groups per molecule is 1.5 or more. 4. The method according to claim 1, wherein the hydroxyl group-containing polymer as the component (B) has a crystallinity of 30% or less.
Item 6. The reversible crosslinkable olefin polymer composition according to item 1.