JPH0699503B2 - Polymer modification method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a block copolymer comprising a vinyl aromatic compound and a conjugated diene, or a block copolymer and a thermoplastic resin and / or a rubber-like polymer. The present invention relates to a method for modifying a polymer, which comprises modifying the mixture with at least one modifier selected from unsaturated carboxylic acids and derivatives thereof in the presence of the phenolic stabilizer.

[Conventional technology]

Heretofore, many attempts have been made to improve the adhesiveness, the green strength, etc. by modifying a resin or rubber with an unsaturated carboxylic acid compound having high functionality, such as a maleic acid compound. For example, Japanese Unexamined Patent Publication (Kokai) No. 50-56427 suggests a method of generating a radical by a radical initiator or heating to maleate a block copolymer composed of butadiene and styrene in the presence of a rubber developing oil. Further, JP-A-55-13720 and JP-A-55-25315 disclose a method of maleating a block copolymer of butadiene and styrene in an organic solvent in the presence of a radical polymerization catalyst. . Further, JP-A-52-123443 also suggests a method of maleating a block copolymer of butadiene and styrene together with polyethylene in a screw type extruder in the presence of a radical initiator.

[Problems to be Solved by the Invention]

However, in any of these methods, maleation occurs under the generation of radicals, and thus gelation of the obtained modified block copolymer is unavoidable. Then, the modified block copolymer results in a marked decrease in properties as a thermoplastic rubber, for example, melt flow properties and appearance properties.

Under these circumstances, the present inventor has conducted extensive studies to solve the above problems, using a screw extruder,
It has been found that when a modification reaction is carried out under a specific reaction condition in the absence of a radical initiator, a modified polymer having excellent melting properties and having a low toluene insoluble content can be obtained.
No. 03 and JP-A-55-60511. However,
The modified block copolymers obtained by the methods disclosed in these documents do not always have good color tones, and their improvement is necessary.

Under these circumstances, the present inventor has investigated a method for obtaining a modified polymer having excellent color tone and melting characteristics and having less gel-like substance mixed therein, and using a specific phenol compound and a sulfur compound having a specific amount in specific amounts. As a result, they have found that the antioxidants that have hitherto been used have an unexpected effect, and have reached the present invention.

[Means and Actions for Solving the Problems]

That is, the present invention has at least one vinyl aromatic hydrocarbon-based polymer segment and at least one conjugated diene-based polymer segment and has a vinyl aromatic hydrocarbon content of 5 to 5. 180% by weight of at least one modifier selected from unsaturated carboxylic acids and their derivatives is added to 95% by weight of a block copolymer or a mixture of the block copolymer and a thermoplastic resin and / or a rubber-like polymer. In the reaction at a temperature of ~ 320 ° C, the block copolymer or the mixture 10
0.05 to 5 parts by weight of the following general formulas [I] and [I
I] in combination with a phenolic compound, or 0.05 ~
5 parts by weight of at least one compound selected from the phenolic compounds represented by the following general formulas [I] and [II],
The modification reaction is carried out in the presence of 0.01 to 5 parts by weight of a sulfur-based stabilizer, a phosphorus-based stabilizer and at least one stabilizer selected from the phenol-based stabilizers represented by the following formulas [III] to [VII]. A method for modifying a polymer, which is characterized in that it is carried out.

(In the above formula, R ₁ represents an alkyl group or an aromatic group, and R ₂ is R ₃ is an alkyl group having 1 to 18 carbon atoms, R ₄ is tert
-Butyl group or cyclohexyl group, R ₅ represents hydrogen or an alkyl group having 1 to 18 carbon atoms. ) (In the above formula, R ₃ and R ₄ are the same as above, R ₆ is an alkenyl group having 2 to 4 carbon atoms, and R ₇ is an alkyl group having 1 to 18 carbon atoms.) The present invention will be described in detail below.

The block copolymer used in the present invention comprises at least 1
, Preferably 2 or more vinyl aromatic hydrocarbon-based polymer segments and at least one conjugated diene-based polymer segment, wherein the vinyl aromatic hydrocarbon content is between 5 and 95. % By weight, preferably 10-90% by weight,
More preferably, it is 15 to 85% by weight. When the content of the vinyl aromatic hydrocarbon is 60% by weight or less, preferably 55% by weight or less, the block copolymer exhibits characteristics as a thermoplastic elastic body, and the content of the vinyl aromatic hydrocarbon is 60% by weight. %, Preferably 65% by weight or more, the thermoplastic resin exhibits properties.

The block copolymer used in the present invention may be produced by any known method, for example, JP-B-36-19286.
Examples thereof include methods described in JP-B No. 43-17979, JP-B-45-31951, and JP-B-46-32415. These are a method of block-copolymerizing a conjugated diene and a vinyl aromatic hydrocarbon in a hydrocarbon solvent using a polymerization initiator such as an organic lithium compound, and are represented by the general formula: (AB) n, AB-A) n. , BA-B) n (in the above formula, A is a polymer segment mainly containing a vinyl aromatic hydrocarbon, and B is a polymer segment mainly containing a conjugated diene. A boundary between the A segment and the B segment Do not necessarily have to be clearly distinguished, and n
Is an integer of 1 or more. ) Or a general formula [(B-Anm ₊₁ X, [(A-Bnm ₊₁ X [(B-AnBm ₊₁ X, [(A-BnAm ₊₁ X (wherein A and B are the same as above. And X is, for example, a polyepoxy compound such as silicon tetrachloride, tin tetrachloride, epoxidized soybean oil, etc., a residue of a coupling agent such as polyhalogenated hydrocarbon, carboxylic acid ester, polyvinyl compound, polyketone compound or a polyfunctional compound. It represents a residue of an initiator such as an organolithium compound, and m and n are integers of 1 or more), which is a block copolymer represented by the above formula. 50% by weight of vinyl aromatic hydrocarbon
It shows a copolymer block of a vinyl aromatic hydrocarbon and a conjugated diene and / or a vinyl aromatic hydrocarbon homopolymer block containing the above, and a polymer block mainly containing a conjugated diene contains 50% by weight of a conjugated diene. 2 shows a copolymer block of a conjugated diene and a vinyl aromatic hydrocarbon and / or a conjugated diene homopolymer block contained in an excess amount. The vinyl aromatic hydrocarbon in the copolymer block may be distributed uniformly or in a taper shape. A plurality of uniformly distributed portions and / or taperedly distributed portions may coexist in each block.

The block copolymer used in the present invention may be any mixture of the block copolymers represented by the above general formula.

The conjugated diene used in the present invention is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene,
2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-
Hexadiene, etc.
Examples include 3-butadiene and isoprene. These are 1
Not only the seeds but also two or more kinds may be mixed and used.

Examples of the vinyl aromatic hydrocarbon used in the present invention include styrene, o-methylstyrene, p-methylstyrene and p-te.
There are rt-butyl styrene, 1,3-dimethyl styrene, α-methyl styrene, vinyl naphthalene, vinyl anthracene and the like, but styrene is particularly common. These may be used alone or in combination of two or more.

Number average molecular weight of the block copolymer used in the present invention 10,0
It is from 00 to 800,000, preferably from 30,000 to 500,000.

In the present invention, it is also possible to use a terminal-modified block copolymer in which a polar group-containing compound is reacted with the active terminal of the polymer to bond a polar group-containing atomic group in the polymer chain. Here, the polar group-containing atomic group means an atomic group containing at least one atom selected from nitrogen, oxygen, silicon, phosphorus, sulfur and tin.

Specifically, carboxyl group, carbonyl group, thiocarbonyl group, acid halide group, acid anhydride group, carboxylic acid group, thiocarboxylic acid group, aldehyde group, thioaldehyde group, carboxylic acid ester group, amide group, sulfonic acid Base,
Sulfonate group, phosphate group, phosphate group,
Amino group, imino group, nitrile group, pyridyl group, quinoline group, epoxy group, thioepoxy group, sulfido group, isocyanate group, isothiocyanate group, silicon halide group, alkoxy silicon group, halogenated tin group, alkyl tin group, phenyl tin group, etc. An atomic group containing at least one polar group selected from More specifically, the terminal modification treatment agent described in Japanese Patent Application No. 61-129179 can be used, and the terminal modification treatment agent described in the specification is within the scope of the present invention. The terminal modification treatment agent for imparting a polar group-containing atomic group is 0.1 to 10 mol, preferably 0.2 to 5 mol, based on one atom equivalent of lithium metal at the polymer terminal,
More preferably, 0.5 to 2 mol is used.

Further, in the present invention, the block copolymer or the terminal-modified block copolymer obtained above can be partially or selectively hydrogenated by a hydrogenation reaction (hydrogenation reaction). The hydrogenation rate can be arbitrarily selected, and in order to improve the heat resistance deterioration while maintaining the properties of the unhydrogenated polymer, the aliphatic double bond based on the conjugated diene is 3% or more, 80% or more.
%, Preferably 5% or more but less than 75% Hydrogenated, or 80% to improve heat deterioration resistance and weather resistance
It is recommended to hydrogenate the above, preferably 90% or more.
In this case, hydrogen of an aromatic double bond based on the vinyl aromatic compound copolymerized with the polymer block A mainly containing the vinyl aromatic compound and the polymer block B mainly containing the conjugated diene compound as the case requires. The addition rate is not particularly limited, but the hydrogen addition rate is preferably 20% or less. The amount of unhydrogenated aliphatic double bonds contained in the hydrogenated block copolymer can be easily known by an infrared spectrophotometer, a nuclear magnetic resonance apparatus or the like. As the catalyst used in the hydrogenation reaction, (1) a supported heterogeneous catalyst in which a metal such as Ni, Pt, Pd, Ru is supported on carbon, silica, alumina, diatomaceous earth, and (2) Ni Known are homogeneous catalysts such as so-called Ziegler-type catalysts that use organic acid salts such as Co, Fe, Cr or acetylacetone salts and reducing agents such as organic Al, or so-called organic complex catalysts such as organic metal compounds such as Ru and Rh. Has been. As a specific method, Japanese Patent Publication No. 42-8704,
According to the method described in JP-B-43-6636 or JP-A-59-133203, JP-A-60-220147,
Hydrogenation can be performed in the presence of a hydrogenation catalyst in an inert solvent to obtain a hydrogenated product, and the hydrogenated block copolymer used in the present invention can be synthesized. At that time, the hydrogenation rate of the aliphatic double bond based on the conjugated diene compound in the block copolymer can be controlled to an arbitrary value by adjusting the reaction temperature, the reaction time, the hydrogen supply amount, the catalyst amount and the like.

In the present invention, a mixture of the block copolymer with a thermoplastic resin and / or a rubber-like polymer can be modified. As the thermoplastic resin, polystyrene, impact-resistant rubber-modified styrene polymer, acrylonitrile-styrene copolymer, styrene-maleic anhydride copolymer, acrylonitrile-butadiene-styrene copolymer, methacrylic acid ester-butadiene-styrene copolymer. Polystyrene resin such as polymer, polyethylene, a copolymer of ethylene containing 50% or more of ethylene and another monomer copolymerizable therewith, for example, an ethylene-propylene copolymer,
Ethylene-vinyl acetate copolymers and hydrolysates thereof, polyethylene-based resins such as ethylene-acrylic acid ionomers and chlorinated polyethylene, polypropylene, propylene containing 50% or more of propylene and a copolymerizable monomer thereof with a copolymerizable monomer. Polymers such as propylene-ethylene copolymers, propylene-ethyl acrylate copolymers, polypropylene resins such as chlorinated polypropylene, polybutene-1, butene-1 and copolymerization with other monomers copolymerizable therewith Polybutene-based resin, polyvinyl chloride, polyvinylidene chloride, vinyl chloride and / or vinylidene chloride containing 50% or more of vinylidene chloride, which is a united body, and co-weight of vinyl chloride and / or vinylidene chloride and other monomer copolymerizable therewith Combined polyvinyl chloride resin, vinyl acetate content is 50% or more Polyvinyl acetate resin which is a copolymer of vinyl acetate and other copolymerizable monomer and its hydrolyzate, acrylic acid and its ester and amide, methacrylic acid and its ester and amide polymer, and these acrylic acid-based resins Polyacrylate resin which is a copolymer with other copolymerizable monomer containing 50% or more of monomers, polymer of acrylonitrile and / or methacrylonitrile, containing 50% or more of these acrylonitrile monomers Nitrile resins that are copolymers with other copolymerizable monomers, linear polymers in which the structural units of the polymers are linked by repeating amide group bonds, such as ε-
Aminocaprolactam and ω-amino laurolactam ring-opening polymer, ε-aminoundecanoic acid condensation polymer, hexamethylenediamen and adipic acid, polyamide resin such as condensation polymer with dibasic acid such as sebacic acid, A linear polymer in which the structural units of the polymer are bonded by repeating ester bonds, for example, a dibasic acid such as phthalic acid or isophthalic acid or a derivative thereof, and a glycol component such as ethylene glycol, propylene glycol or butylene glycol. Polyester resin which is a condensate, polyphenylene ether resin or grafted polyphenylene ether resin obtained by graft-polymerizing vinyl-substituted aromatic hydrocarbon on the resin, polyphenylene sulfide resin, polyoxymethylene, trioxane and alkylene. Polyacetate such as copolymer with oxide Tar-based resins, linear polymers in which structural units of the polymer are bonded by repeating carbonic acid ester type bonds, for example, dihydroxy such as 4,4'-dihydroxydiphenylalkane and 4,4'-dihydroxydiphenyl sulfide. Polymers obtained by the reaction of a compound and phosgene, or polycarbonate resins such as polymers obtained by the transesterification reaction of the dihydroxy compound and diphenyl carbonate, polyethersulfone, polysulfone resins such as polyallylsulfone,
Thermoplastic polyurethane resin obtained by polyaddition reaction of diisocyanate component and glycol component, polybutadiene resin such as trans polybutadiene and 1,2-polybutadiene, and polyarylate which is polycondensation polymer composed of bisphenol A and phthalic acid component. Examples of the resin include a series resin, a fluororesin having a structure in which a part or all of hydrogen in a chain hydrocarbon polymer compound is replaced with fluorine, a polyoxybenzoyl resin, and a polyimide resin.

As the rubber-like polymer, polybutadiene, polyisoprene, styrene-butadiene copolymer, butadiene-
Acrylonitrile copolymer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, polybutene, thermoplastic polyester elastomer, thermoplastic polyamide elastomer, thermoplastic polyurethane elastomer, silicone rubber, epichlorohydrin rubber, acrylic rubber, ethylene- Examples thereof include vinyl acetate copolymer fluororubber.

In the present invention, the mixing ratio (weight ratio) in the case of modifying the block copolymer with a thermoplastic resin or a rubber-like polymer is generally 99/1 to 3/97, preferably 97/3 to
It is 5/95. These may be mixed in advance, or may be mixed in the denaturing reaction device during the denaturing reaction. The modified product of the mixture of the block copolymer and the thermoplastic resin or the rubber-like elastic material is excellent in compatibility with the unmodified thermoplastic or rubber-like elastic material, and at the same time, the block copolymer. Higher temperature than when used alone, e.g. 200-3
The denaturing reaction at 20 ° C, preferably 220 to 300 ° C can be carried out more smoothly.

Examples of the unsaturated carboxylic acid and derivative which are the modifiers used in the present invention include maleic acid, maleic anhydride, maleic acid ester, maleic acid amide, maleic acid imide,
Fumaric acid, fumaric acid ester, fumaric acid amide, fumaric acid imide, itaconic acid, itaconic anhydride, itaconic acid ester, itaconic acid amide, itaconic acid imide, halogenated maleic acid, anhydrous halogenated maleic acid, halogenated maleic acid ester , Halogenated maleic amide,
Halogenated maleic acid imide, cis-4-cyclohexene-1,2-dicarboxylic acid, cis-4-cyclohexene-1,2-dicarboxylic acid anhydride, cis-4-cyclohexene-
1,2-dicarboxylic acid ester, cis-4-cyclohexene-1,2-dicarboxylic acid amide, cis-4-cyclohexene-1,2-dicarboxylic acid imide, endo-cis-bicyclo (2,2,1) -5 -Heptene-2,3-dicarboxylic acid, anhydrous endo-cis-bicyclo (2,2,1) -5-heptene-
2,3-dicarboxylic acid, endo-cis-bicyclo (2,2,1)
-5-heptene-2,3-dicarboxylic acid ester, endo-cis-bicyclo (2,2,1) -5-heptene-2,3-dicarboxylic acid amide, endo-cis-bicyclo (2,2,1) −
Examples thereof include 5-heptene-2,3-dicarboxylic acid imide, acrylic acid, acrylic acid ester, acrylic acid amide, methacrylic acid, methacrylic acid ester (eg methyl methacrylate, glycidyl methacrylate), and methacrylic acid amide. These can be used not only as one type but also as a mixture of two or more types. Of these, unsaturated dicarboxylic acids or derivatives thereof are preferable, and maleic anhydride is particularly preferable.

In the present invention, the amount of the at least one modifier selected from unsaturated carboxylic acids and derivatives thereof is generally 0.1 to 10 per 100 parts by weight of the block copolymer or the mixture.
0 parts by weight, preferably 0.3 to 50 parts by weight, more preferably 0.
5 to 20 parts by weight. When the amount of the modifier is too small, the modifying effect is small, while when the amount of the modifier is too large, the color tone deteriorates, and it becomes complicated to remove the unreacted modifier from the modified product, or the modification It is not preferable because a homopolymer of the agent itself is mixed.

In the present invention, the temperature at which the modifier is reacted with the block copolymer or the mixture is 180 to 320 ° C., preferably 20
0 to 280 ° C. When the reaction temperature is less than 180 ° C, the reaction rate of the modifier is low and the modifying effect is small, which is not preferable. On the other hand, if the reaction temperature is higher than 320 ° C., the color tone and the melting property are deteriorated, and the gel-like substance insoluble in the solvent such as toluene is often produced, which is not preferable. In the present invention, it is preferable to carry out the modification reaction in the absence of a radical initiator such as a peroxide or an azo compound in order to suppress the formation of a gelled material during the modification reaction. An operation such as increasing the reaction rate of the modifier may be carried out by using a small amount of the radical initiator within a range that does not cause formation.

As the radical initiator, those having a decomposition temperature of 100 to 200 ° C. for obtaining a half-life of 10 hours are generally preferred, and specific examples thereof include α, α′-bis (tert-butylperoxy-m-isopropyl). ) Benzene, dicumyl peroxide, di-tert-butyl peroxide, tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di (tert
-Butylperoxy) hexane and 2,5-dimethyl-
2,5-di (tert-butylperoxy) hexyne-3, n
-Butyl 4,4-bis (tert-butylperoxy) valerate, 1,1-bis (tert-butylperoxy) 3,3,5-trimethylcyclohexane, tert-butyl hydroperoxide, cumene hydroperoxide, diisopropyl Benzene hydroperoxide, paramenthane hydroperoxide, 2,5-dimethylhexane-2,5-
Examples thereof include dihydroperoxide and 1,1,3,3-tetramethylbutyl hydroperoxide. These radical initiators may be the block copolymer or the mixture.
Generally 0.001 to 5 parts by weight, preferably 0.01 per 100 parts by weight
To 2 parts by weight, more preferably 0.05 to 1 part by weight.

The most important feature of the present invention is 0.05 to 5 parts by weight, preferably 0.1 to 5 parts by weight per 100 parts by weight of the block copolymer or the mixture.
The modification reaction is carried out in the presence of 2 parts by weight of at least one selected from the phenolic compounds represented by the general formulas [I] and [II]. When the amount of each of the phenolic compounds used is less than 0.05 parts by weight, the effect of improving the color tone and the melting property and the effect of suppressing the formation of the gel-like substance are not observed. The above effect is not exhibited. In the compound represented by the general formula [I], the substituent R ₁ represents an alkyl group or an aromatic group, and specifically, an alkyl group having 1 to 24 carbon atoms, a cycloalkyl group, an alkyl-substituted cycloalkyl group, phenyl Examples thereof include a group, an alkyl-substituted phenyl group, a biphenyl group and an alkyl-substituted biphenyl group, but a paraphenylene group is particularly preferable. The substituent R ₃ has 1 to 18 carbon atoms, preferably 1
To 8 and more preferably 1 to 4 alkyl groups, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isobutyl group, a tert-butyl group, an isoamyl group, a tert-amyl group and a tert-octyl group. Examples thereof include methyl group, tert-butyl group and tert-amyl group. The substituent R ₄ is preferably a tert-butyl group. Specific examples of the substituent R ₅ include hydrogen, methyl group, ethyl group, propyl group and butyl group, with hydrogen or methyl group being particularly preferred. The substituent R ₆ is an alkenyl group having 2 to 4 carbon atoms, specifically, an ethenyl group, an isopropenyl group, a propenyl group, an isobutenyl group, a butenyl group and the like. Particularly preferred is the ethenyl group. Specific examples of the substituent R ₇ include a methyl group, an ethyl group, a propyl group and a butyl group, and a methyl group and a propyl group are particularly preferable.

In the present invention, at least one selected from the phenolic compounds represented by the following general formulas [III] to [VII] in order to obtain a modified polymer having more excellent color tone and melting characteristics and further containing less gel-like substance 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight.

(In the above formula, R ₃ , R ₄ and R ₆ are the same as above, and R ₈
Is Indicates. R ₉ represents an alkyl group having 2 to 20 carbon atoms, preferably 4 to 18 carbon atoms, and specific examples thereof include a cyclohexyl group, an octyl group and a dodecyl group. In the present invention, as specifically described in Examples, the phenol compounds represented by the general formulas [I] and [II] are used in combination, or the general formulas [I] and [II] are used. ] At least 1 selected from the phenolic compounds represented by
In addition to the seed stabilizer, at least one of other phenolic compounds, other sulfur stabilizers and phosphorus stabilizers is added to 0.01
~ 5 parts by weight can be used in combination. Preferable specific examples thereof include (A) 3,9-bis [2- {3- (3-tert-butyl-
4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, triethyleneglycol-bis [3- (3- tert-butyl-5-methyl-
4-Hydroxyphenyl) propionate], 1,3,5-
Tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid, 2,2'-methylene-
Bis (4-methyl-6-tert-butylphenol), 1,
1,3-tris (2-methyl-4-hydroxy-5-tert
-Butylphenyl) butane, 2,2'-methylene-bis-
(4-ethyl-6-tert-butylphenol), 2,2 '
-Methylene-bis- (4-methyl-6-sylohexylphenol), 4,4'-thiobis- (3-methyl-6-ter
(B-) Dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3 ′ -Thiodipropionic acid ester, lauryl stearyl-3,3′-thiodipropionic acid ester, pentaerythritol tetrakis- (lauryl thiopropionate), 3,9-bis (2-dodecylthioethyl) -2,4 , 8,10-Tetraoxaspiro [5 ・
5] At least one sulfur stabilizer selected from undecane and 3,9- (2-octadecylthiopropyl) -2,4,8,10-tetraoxaspiro [5.5] undecane (C) Tris (nonyl) Phenyl) phosphite, cyclic neopentanetetraylbis (octadecylphosphite), tris (2,4-di-tert-butylphenyl) phosphite, 4,4'-butylidene-bis (3-methyl-6-tert) -Butylphenyl-di-tridecyl) phosphite, 4,4'-biphenylenediphosphinic acid tetrakis (2,4-di-tertbutylphenyl),
Cyclic neopentane tetrayl bis (2,4-di-t
At least one phosphorus-based stabilizer selected from ert-butylphenyl) phosphite. These can generally be used in an amount of 0.05 to 5 parts by weight, preferably 0.1 to 2 parts by weight, per 100 parts by weight of the block copolymer or the mixture.

In the present invention, a block copolymer or a mixture of the block copolymer and a thermoplastic resin or a rubbery polymer is selected from the phenolic compounds represented by the general formulas [I] and [II] defined in the present invention. The composition may be prepared by pre-blending at least one of the above compounds and then used in the modification method of the present invention. Further, at least one selected from the phenolic compounds represented by the general formulas [I] and [II] defined in the present invention in a block copolymer or a mixture of the block copolymer and a thermoplastic resin or a rubber-like polymer. And at least one selected from the phenolic compounds represented by the general formulas [III] to [VII] and / or the above (A), (B),
The composition may be prepared by previously blending at least one kind of the stabilizer (C), and then used in the modification method of the present invention.

The method of the present invention is preferably carried out in the absence of an organic solvent and under melt kneading, but may be carried out in a state of being dissolved in an organic solvent if necessary. Examples of the melt-kneading method include a method using a general kneader such as an internal mixer, a co-kneader, a continuous kneader with a twin-screw rotor, a single-screw, a twin-screw or a multi-screw extruder, and particularly an extruder is used. The method is preferable for continuous production. In the melt-kneading method using an extruder, the average residence time in the extruder is generally 10 to 1000 seconds, preferably 30 to 500 seconds. If the average residence time is too short, problems such as low reaction rate or nonuniform reaction occur, while if the average residence time is too long, gelled substances become prominent, which is not preferable. .

Further, in the method of the present invention, the amount of the unreacted modifier remaining in the modified polymer after the modification reaction is 1 part by weight or less, preferably 0.5 part by weight or less, per 100 parts by weight of the modified polymer. Is preferable in order to obtain a modified polymer having an excellent color tone.
For this purpose, it is recommended that the modification reaction is carried out by using an extruder equipped with a ventable device and removing the unreacted modifying agent from the vent section by means such as decompression.

In the method of the present invention, the modification reaction can be carried out in the presence of a basic inorganic compound to obtain an ionic crosslinked modified polymer. Basic inorganic compounds are generally monovalent, divalent and trivalent metal compounds such as sodium compounds,
Potassium compounds, magnesium compounds, calcium compounds, zinc compounds, aluminum compounds and the like,
Suitable examples of these metal compounds include hydroxides, alcoholates, carboxylates and oxides. Among them, magnesium hydroxide, magnesium oxide, calcium hydroxide, aluminum hydroxide, compounds mainly containing them, and mixtures thereof can be preferably used. The addition amount of these is 0.01 to 5 parts by weight, preferably 0.05 to 3 parts by weight, based on 100 parts by weight of the block copolymer or the mixture.

The modified polymer obtained by the present invention, in addition to the thermoplastic polymer and the rubber-like polymer, a reinforcing agent, a filler, an antioxidant, an ultraviolet absorber, a colorant, a pigment, a lubricant, a flame retardant, It is possible to add foaming agents and other additives. More specific examples of the above-mentioned additives that can be added to the modified polymer obtained in the present invention are described in "Handbook Rubber / Plastic Compounded Chemicals, 1974, issued by Rubber Digest".

〔The invention's effect〕

The present invention not only provides an industrial production method for stably obtaining a polymer modified with an unsaturated carboxylic acid or a derivative thereof, but also has an excellent color tone and melt adhesion property, and a modified heavy polymer containing less gel-like substances. A coalescence is obtained. The modified polymer obtained according to the present invention is modified with an unsaturated carboxylic acid or a derivative thereof to make use of various thermoplastic resin / thermosetting resin modifiers, footwear materials, pressure sensitive adhesives / adhesives. It can be used as a material, asphalt modifier, wire cable material, vulcanized gum modifier, etc.

〔Example〕

The following examples are given to explain the present invention in more detail, but these examples are for showing the excellent effects obtained by the present invention, and do not limit the scope of the present invention. . The block copolymer used in the examples of the present invention was manufactured as follows.

[Block copolymer (A)]

In a nitrogen gas atmosphere, n-butyllithium was added to an n-hexane solution containing 15 parts by weight of 1,3-butadiene and 20 parts by weight of styrene, and the mixture was polymerized at 70 ° C. for 2 hours.
N containing 45 parts by weight of 1,3-butadiene and 20 parts by weight of styrene
-Hexane solution was added and the mixture was polymerized at 70 ° C for 2 hours. The polymer obtained has a styrene content of 40% by weight, MI (G) of 10 g / 10 mi.
It was a block copolymer of n BABA structure.

[Block copolymer (B)]

In a nitrogen gas atmosphere, n-butyllithium was added to a cyclohexane solution containing 30 parts by weight of styrene, and the temperature was 70 ° C.
After 1 hour of polymerization, a cyclohexane solution containing 70 parts by weight of 1,3-butadiene was added and the mixture was polymerized at 70 ° C. for 2 hours. Thereafter, tetrachlorosilane was added to 1/4 mol of the used n-butyllithium to give a styrene content of 30% by weight, MI.
(G) A block copolymer having 20 g / 10 min (AB ₄ Si structure was obtained.

[Block copolymer (C)]

In a nitrogen gas atmosphere, a cyclohexane solution containing 30 parts by weight of styrene and 0.3 parts by weight of tetrahydrofuran was added to the solution.
-Add butyllithium, polymerize at 70 ° C for 1 hour,
A cyclohexane solution containing 20 parts by weight of 1,3-butadiene and 50 parts by weight of styrene was added and polymerization was carried out at 70 ° C. for 2 hours. The polymer obtained had a styrene content of 80% by weight, MI (G) of 8 g / 10 m.
It was a block copolymer having an ABA structure of in.

Examples 1 to 7 and Comparative Examples 1 to 4 100 parts by weight of block copolymer (A) and maleic anhydride 2
After compounding parts by weight and the stabilizers shown in Table 1, 30
It was supplied to an mmφ extruder and a maleation reaction was carried out at 240 ° C. The average residence time in the extruder was about 90 seconds. Unreacted maleic anhydride was removed by a reduced pressure from a vent portion attached to a portion near the tip of the extruder so that the amount of residual maleic anhydride in the modified polymer was 0.2% by weight or less.

The amount of maleic anhydride added to each of the modified block copolymers obtained was 0.4 to 0.6% by weight. Table 1 shows the melt viscosity retention rate, toluene insoluble content, and color tone of the obtained modified block copolymer. It can be seen that the modified block copolymer, which has been subjected to the modification reaction in the presence of the phenolic compound specified in the present invention, is excellent in color tone and melt viscosity characteristics, and contains little toluene-insoluble gel-like substance.

In Example 1, when the unreacted maleic anhydride was not removed from the vent portion, the modified block copolymer pellets obtained had ab value of 38 and a slightly poor color tone. The amount of unreacted maleic anhydride in this modified block copolymer was 1.3% by weight.

(Note 1) The blending amount of each stabilizer indicates the blending ratio (parts by weight) with respect to 100 parts by weight of the block copolymer or a mixture of the block copolymer and the thermoplastic resin or the rubber-like polymer.

The following were used as stabilizers.

A0-1: In the general formula [I], R ₃ is a methyl group, and R ₄ is t
ert-butyl group, R ₅ has R ₆ is hydrogen, R ₁ is a phenolic compound A0-2 is a para-phenylene group; in the general formula [II], R ₃ and R ₄ is tert-
Butyl group, R ₆ is an ethenyl group, R ₇ is a methyl group phenol compound A0-3; 2-tert-butyl-6- (3-tert-butyl-2-
Hydroxy-5-methylbenzyl) -4-methylphenyl acrylate A0-4; 3,9-bis [2- {3- (3-tert-butyl-4-
Hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane A0-5; n-octadecyl-3- (3 ', 5'-di-tert-
Butyl-4'hydroxyphenyl) propionate A0-6; tetrakis- [methylene-3- (3 ', 5'-di-
tert-butyl-4'hydroxyphenyl) propionate] methane A0-7; 1,3,5-trimethyl-2,4,6-tris (3,5-di-t
ert-Butyl-4-hydroxybenzyl) benzene A0-8; 2,4-bis- (n-octylthio) -6- (4-
Hydroxy-3,5-di-tert-butylanilino) -1,3,5
-Triazine A0-9; tris (nonylphenyl) phosphite A0-10; tris (2,4-di-tert-butylphenyl) phosphite A0-11; 2,6-di-tert-butyl-4-methylphenol A0-12; distearyl-3,3'-thiodipropionate A0-13; in the general formula (II), R ₃ is tert- amyl, R ₄ is tert- butyl group, R ₆ is ethenyl , R ₇ is a methyl group phenolic compound (Note 2) Melt viscosity characteristics were judged by the melt viscosity retention rate.

Melt flow was measured under G condition (200 ° C., 5 kg load), and judgment was made according to the following criteria.

◎: Retention rate of 80% or more ○: Retention rate of 60% or more and less than 80% △: Retention rate of 40% or more and less than 60% ×: Retention rate of less than 40% (Note 3) 5 g of modified polymer is melted in 200 g of toluene After that, the mixture was filtered through a 100-mesh wire net, the toluene-insoluble matter remaining in the wire-mesh was vacuum dried at 90 ° C. for 2 hours, and the weight was measured to determine the proportion of the toluene-insoluble matter. The toluene insoluble content was judged according to the following criteria.

◎; less than 0.05% by weight ○; 0.05% by weight or more and less than 0.1% by weight △; 0.1% by weight or more and less than 0.5% by weight ×; 0.5% by weight or more (Note 4) The color tone of the modified polymer in pellet form is Nippon Denshoku It was examined with an ND-V6B integrated visual measuring instrument manufactured by Kogyo Co., Ltd. The quality of the color tone was measured by the b value according to the following criteria. The larger the b value, the larger the apparent yellowness.

◎; b value less than 30 ○; b value 30 or more, less than 35 △; b value 35 or more, less than 40 ×; b value 40 or more Comparative Example 5 Using 0.5 parts by weight of phenothiazine instead of the phenol compound in Example 1. The modification reaction was carried out in the same manner as in Example 1. The melt viscosity retention rate and toluene insoluble content of the obtained modified block copolymer were both good (rank ⊚), and the color tone was at the level of rank Δ. When the above modified block copolymer was exposed to sunlight for 1 week, the color changed to reddish brown and the color tone was poor. (Rank x).
The modified block copolymers of Examples 1 to 7 showed almost no discoloration under the same sun exposure conditions.

Comparative Example 6 When the modification reaction of Example 1 was carried out at 330 ° C., gelation occurred during the modification reaction, and a smooth modification reaction could not be carried out.

Examples 8 to 28 According to the compounding method shown in Table 2, after mixing the stabilizers with 100 parts by weight of the mixture of the block copolymer and the thermoplastic resin or the rubber-like polymer, the cylinder temperature was changed to Table 2 The mixture was supplied to a 30 mmφ extruder set to the temperature shown in 1 above, and extrusion kneading and granulation were performed. Average residence time in the extruder is 60 ~
Adjusted to a range of 120 seconds.

The melt viscosity of the obtained block copolymer mixture shows a markedly higher melt viscosity than the block copolymer mixture obtained by using the stabilizers outside the scope of the present invention, and the color tone is good and the gel-like insoluble matter is present. There was little mixing of things.

(Note 5) MMA; methyl methacrylate polymer PA; nylon-6,6 ABS; acrylonitrile-butadiene-styrene copolymer PC; polycarbonate TPET; thermoplastic polyester elastomer NBR; acrylonitrile-butadiene copolymer AS; acrylonitrile-styrene copolymer Polymer PPE; Polyphenylene ether PET; Polyethylene terephthalate PBT; Polybutylene terephthalate PS; Polystyrene MS; Methyl methacrylate / styrene copolymer PP; Polypropylene PB; 1,2-Polybutadiene (Note 6) Stabilizers A; A0-1 ... 0.5 parts by weight, A0-3 ... 0.5 parts by weight, A0-6 ... 0.5 parts by weight, A0-9 ... 1.0 parts by weight Stabilizer B; A0-2 ... 1.0 parts by weight, A0-3 ... 0.5 parts by weight, A0 -Ten
... 0.5 parts by weight, stabilizers C; A0-1 ... 0.2 parts by weight, A0-2 ... 0.5 parts by weight, A0-12
… 1.0 parts by weight, A0-8… 0.5 parts by weight Stabilizer D; A0-5… 0.5 parts by weight, A0-8… 0.5 parts by weight, A0-10
… 0.5 parts by weight, A0-13… 0.5 parts by weight (Note 7) Stabilizers are A0 as a comparative example corresponding to each example.
-11 ... 1.0 parts by weight, A0-9 ... 0.5 parts by weight, A0-12 ... 0.5 parts by weight, the modification reaction was carried out, and the melt flow of the modified polymer of Example and the modified polymer of Comparative Example (measurement conditions were ASTM D-
(In accordance with 1238) was compared and the melt viscosity measurement was judged according to the following criteria.

(Melt flow of modified polymer of Example)-(melt flow of modified polymer of Comparative Example) ◎; 2g / 10min or more ○: 1g / 10min or more, less than 2g / 10min △; 0.5g / 10min or more, 1g / 10min Less than ×; less than 0.5 g / 10 min Examples 29 to 49 According to the compounding method shown in Table 3, 100 parts by weight of a mixture of a block copolymer and a thermoplastic or rubbery polymer was added to 5 parts by weight of maleic anhydride. Cylinder temperature is set to the temperature shown in Table 3 after compounding stabilizers and 30mm
It was supplied to a φ extruder to carry out a maleation reaction. The average residence time in the extruder was adjusted to the range of 60 to 120 seconds. Unreacted maleic anhydride was removed from the pent section attached near the tip of the extruder by reduced pressure so that the amount of maleic anhydride remaining in the modified polymer was 0.3% by weight or less.

The amount of maleic anhydride added to the obtained modified block copolymer was 0.2 to 1.5% by weight. Also, the melt viscosity of the obtained modified block copolymer shows a markedly better melt viscosity than the modified block copolymer obtained by using the stabilizers outside the scope of the present invention, and the color tone is good and gel-like. The mixture of insoluble matter was small.

Example 50 Before deactivating the block copolymer (A), N-methylpyrrolidone was reacted with the active end of the block copolymer (A), and an end-modified block copolymer having N-methylpyrrolidone reaction residue bonded to the polymer chain end was used. Was produced. Examples 8 to 28 except that the end-modified block copolymer is used as the block copolymer
A denaturing reaction was carried out in the same manner as in. Each of the obtained modified products exhibited the same good melt viscosity characteristics as in Examples 8 to 28.

Example 51 The block copolymer (B) was hydrogenated with a Ti-based hydrogenation catalyst described in JP-A-59-133203, and the hydrogenation rate of the butadiene part was
A 30% hydrogenated block copolymer was obtained. Examples except that the hydrogenated block copolymer is used as the block copolymer
The denaturing reaction was performed by the same method as 36 to 43. All of the obtained modified products showed good melt viscosity characteristics similar to those of Examples 36 to 43.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C08L 71/12 LQP 77/00 LQS

Claims (1)

[Claims] 1. A polymer segment containing at least one vinyl aromatic hydrocarbon as a main component and at least one polymer segment containing a conjugated diene as a main component, and having a vinyl aromatic hydrocarbon content of 5 to 95. 180% by weight of at least one modifier selected from unsaturated carboxylic acids and their derivatives in a block copolymer or a mixture of the block copolymer and the thermoplastic resin and / or rubber-like polymer in a weight percentage of When the reaction is carried out at a temperature of 320 ° C., a combination of 0.05 to 5 parts by weight of a phenolic compound represented by the following general formulas [I] and [II] per 100 parts by weight of the block copolymer or the mixture,
Or 0.05 to 5 parts by weight of at least one compound selected from the phenolic compounds represented by the following general formulas [I] and [II], and 0.01 to 5 parts by weight of a sulfur-based stabilizer, a phosphorus-based stabilizer and the following: A method for modifying a polymer, which comprises performing a modification reaction in the presence of at least one stabilizer selected from the phenolic stabilizers represented by formulas [III] to [VII]. (In the above formula, R ₁ represents an alkyl group or an aromatic group, and R ₂ is R ₃ is an alkyl group having 1 to 18 carbon atoms, R ₄ is tert
-Butyl group or cyclohexyl group, R ₅ represents hydrogen or an alkyl group having 1 to 18 carbon atoms. ) (In the above formula, R ₃ and R ₄ are the same as above, R ₆ is an alkenyl group having 2 to 4 carbon atoms, and R ₇ is an alkyl group having 1 to 18 carbon atoms.)