JPH04149236A - Production of graft copolymer - Google Patents

Abstract

PURPOSE:To obtain the subject copolymer suitable as modifying agents, etc., for resins by reacting a specific copolymer with a borane compound, then oxidizing the part bound to the boron and then reacting the resultant copolymer with a modified olefinic resin containing an unsaturated carboxylic acid introduced thereinto. CONSTITUTION:A copolymer of (i) an alkenyl aromatic compound such as styrene and (ii) a conjugated diene compound such as isoprene is made to react with (iii) a borane compound, expressed by the formula (Z<1> and Z<2> are H, alkyl, etc.) and having boron-hydrogen bond, preferably at-10 to +150 deg.C, then reacted with, e.g. hydrogen peroxide and oxidized to provide (A) an alcoholic hydroxyl groupmodified copolymer. On the other hand, ethylene is reacted with acrylic acid to afford (B) an unsaturated carboxylic acidmodified olefinic resin, which is subsequently reacted with the component (A), preferably at 0-400 deg.C to afford the objective copolymer.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a copolymer having both a polymer chain mainly consisting of an alkenyl aromatic compound and a polymer chain mainly consisting of a conjugated diene compound in the same molecule. The present invention relates to a method for producing a graft copolymer with a modified olefin resin.

This graft copolymer itself is a thermoplastic resin having excellent physical properties, and is also an excellent resin modifier and resin compatibilizer. In particular, since the graft copolymer has a polymer chain with rubber-like properties mainly composed of a conjugated diene compound, when used as a resin modifier or a phase droplet forming agent, the effect of improving impact resistance is large.

(Prior Art) Graft or block copolymers using olefin resins are synthesized by various methods as shown below.

Many attempts have been made to graft-polymerize radically polymerizable monomers onto polyolefins for a long time, and are disclosed, for example, in Japanese Patent Laid-Open Nos. 49-55790 and 50-32287.

However, in general, radical graft polymerization methods do not have a sufficiently high grafting rate or grafting efficiency, and in many cases, radical polymerization initiators such as organic peroxides are used, so molecular cleavage and crosslinking reactions of the backbone polymer to be grafted are prevented. This easily occurs, and the desired graft copolymer cannot be obtained efficiently.

On the other hand, by using a specific vanadium-based Ziegler-Natsuta type catalyst that has the ability to live polymerize α-olefins, a radical group is formed at the active end of the living polyolefin, and methyl methacrylate is polymerized.
Method for producing block copolymers of olefins and methyl methacrylate (Makromol, Chem, 1
86.11.1985), and a method in which a block copolymer of α-olefin and styrene is obtained by adding a halogen to the active end of the living polyolefin and coupling this with living polystyryllithium (C, C, Pr1ce[”Coordinati
on Polymerization.

Plenum Pub, New York, 198
3. P, 24B).

However, since these methods polymerize α-olefins using specific Ziegler-Natsuta type catalysts, the chain block portions of the produced polyolefins have specialized polymer structures. Therefore, it is inevitable that the uses of block copolymers obtained by these methods will be limited.

Furthermore, as a method similar to the above, a halogen is added to the terminal double bond of a polyolefin obtained using a so-called Kaminski type Ziegler-Natsuta type catalyst, and a coupling reaction between the halogen and living polystyryllithium is performed to obtain α.
- There is a method for obtaining a block copolymer of olefin and styrene (Japanese Unexamined Patent Publication No. 158709/1983). However, in this method, unreacted halogen remains in the reaction product, which tends to cause deterioration of the polymer during heat treatment such as molding after synthesis.

In addition, a method for obtaining a block copolymer of polyolefin, polystyrene, and polybutadiene using anionic polymerization active sites and Ziegler-Natsuta type polymerization activation methods (Japanese Unexamined Patent Publication No. 60-20918, Eu
r, Polym, J, 17°1175, 1,98
1, Makromol, Chem, 181.18
15°1980).

However, these methods have various problems, such as a decrease in catalyst activity and blocking efficiency due to low active site conversion efficiency, and difficulty in obtaining a copolymer with the desired controlled molecular weight. have.

In addition, the conventional technology is a binary proton or graft copolymer containing an olefin resin, and a tertiary system, especially a graft copolymer containing a polymer chain having rubber-like properties mainly composed of a conjugated diene compound. The polymer has not been synthesized.

(Problems to be Solved by the Invention) In order to solve the above-mentioned problems, the present invention provides a polymer chain #ji (a) mainly consisting of an alkenyl aromatic compound and a polymer chain (b) mainly consisting of a conjugated diene compound. ) as a trunk polymer and an olefin resin as a branch polymer.

(Means for Solving the Problems) The present invention combines a polymer chain (a) mainly consisting of an alkenyl aromatic compound and a polymer chain mainly consisting of a conjugated diene compound [(b) in the same molecule. The copolymer (c) with the general formula % (in the formula, Zl and Z2 each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydrocarbon oxy group, or a halogen atom) An alcoholic hydroxyl group-modified copolymer obtained by reacting a borane compound having at least one boron-hydrogen bond and then oxidizing the poron bonding site is reacted with a modified olefin resin into which an unsaturated carboxylic acid or a derivative thereof has been introduced. This is a method for producing a graft copolymer, which is characterized by:

(1) Alcoholic hydroxyl group-modified copolymer A polymer chain (a) mainly containing an alkenyl aromatic compound (hereinafter referred to as chain (a)) and a conjugated diene compound in the same molecule used in the present invention Polymer chain (b) (hereinafter referred to as chain (b)
copolymer (C) (hereinafter referred to as copolymer (
(referred to as c)) is a copolymer (c) that has a small number (one each) of chains (a, ) and chains (b) in the same molecule, and chains (a) and chains (b) are It includes a so-called linear block structure connected in a shape, a so-called radial teleblock structure connected in a branched manner, or a so-called graft-like branched structure in which one side is a trunk and the other is a branch.

The alkenyl aromatic compound used in the present invention has the general formula (wherein R1 and R2 each represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkenyl group having 1 to 6 carbon atoms, and R
3 and R4 each represent a hydrogen atom, a C1-6 alkyl group, or a halogen atom, and R5, R6, and R7 each represent a hydrogen atom, a halogen atom, a C1-6 alkyl group, or a C1-6 alkyl group. represents an alkenyl group, or R6 and R
? forms a part of an aromatic ring, and may form a naphthyl group, etc.).

Specific examples of alkenyl aromatic compounds include styrene,
Examples include α-methylstyrene, vinylxylene, vinyltoluene, vinylnaphthalene, divinylbenzene, bromostyrene or chlorostyrene, among which styrene, a-methylstyrene, vinyl Toluene and vinylxylene are preferred, and styrene is more preferred.

Chain (a) contains 25% by weight based on 100% of its total weight.
It may contain copolymer components other than alkenyl aromatic compounds within a range not exceeding % by weight.

The conjugated diene compound used in the present invention is not particularly limited, but is usually one of unsubstituted, 2-substituted or 23-substituted 1,3-dienes of diolefinic unsaturated hydrocarbons having 4 to 12 carbon atoms. Consists of at least one type. Examples of the substituent include an alkyl group, an aryl group, a halogen atom, a cyano group, and a nitro group.

Specific examples of conjugated diene compounds include 1,3-butadiene,
Examples include isoprene, chlorobrene, 2-cyano-1,3-butadiene, and 2,3-dimethyl-1,3-butadiene.

Chain (b) has a weight of 25% by weight based on its total weight of 100%.
It may contain a copolymer component other than the conjugated diene compound within a range not exceeding % by weight.

The proportion of chains (a) in copolymer (c) is
) at 5 to 95% by weight based on 100% by weight of the total weight of
The proportion of chain (b) is preferably in the range of 95 to 5% by weight.
The molecular weight, molecular weight distribution, and manufacturing method of the copolymer (c) are not particularly limited.

The poran compound (I) used in the present invention contains at least 1
The substituents are independently a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydrocarbon oxy group, or a halogen atom. Specific examples include diborane and complex compounds of borane and Lewis bases, such as borane-tetrahydrofuran complex, borane-triethylamine complex, borane-pyridine complex, borane-ammonium complex, borane-t-
Butylamine complex, borane-N,N-diethylaniline complex, borane-N,N-diisopropylethylamine complex, borane]nodimethylamine complex, borane-4-dimethylaminopyridine complex, borane-4-ethylmorpholine complex, borane- 2,6-lutidine complex, borane-4
-Methylmorpholine complex, borane-methylsulfide complex, borane-morpholine complex, borane-1,4-thioxane complex, borane-4-phenylmorpholine complex, borane-piperidine complex, borane-poly(2-vinylpyridine) complex, borane-pyridine complex, porane-tributylphysphine complex, borane-triphenylphosphine complex, as well as 3-(methylthio)propylborane, thexylporane, catecholborane, 9-borabicyclo[3,3,],]nonane (abbreviation 49-BEN), dithiamylborane, dichloroborane, dicyclohexylborane, etc., and preferably borane-tetrahydrofuran complex, poran-pyridine complex, borane-methylsulfide complex, or borane-methylsulfide complex from the viewpoint of easy availability and chemical stability.
~BBN etc.

The reaction between the copolymer (e) and the borane compound (1) having one boron-hydrogen bond is a so-called hydroboration reaction, in which the unsaturated double bond in the chain (b) and the borane compound The 6-hydroboration reaction is carried out in a solvent under an inert gas atmosphere, preferably under a nitrogen gas or argon gas atmosphere, and is not particularly limited as long as it is a sufficiently dehydrated aprotic solvent.
Aprotic polar melts such as tetrahydrofuran, dioxane or diglyme are preferred.

Furthermore, there is no restriction on the amount of the borane compound used.

The reaction temperature is between -10°C and 150°C, and higher temperatures are advantageous for the reaction to proceed. In addition, when using a poran compound containing two or three or more boron-hydrogen bonds, gelation of the copolymer (C) occurs due to the hydroboration reaction, but the final product containing hydroxyl groups is formed by the subsequent oxidation reaction. There is no gel formation in the copolymer.

Although the reaction time depends on reaction conditions such as temperature, the reaction is almost completed within 30 minutes, and sufficient results can be obtained in 1 hour.

In the borane-modified copolymer of the present invention, which is obtained by reacting the copolymer (c) with the borane compound (I), the borane-carbon bond site can be easily converted into an aliphatic alcoholic hydroxyl group by an oxidation reaction under alkaline conditions. I can do it.

As the oxidizing agent, hydrogen peroxide is most preferred, but oxidized oxyamines and air can also be used.

Hydrogen peroxide can be used in various concentrations, but an aqueous solution of 20 to 40% by weight is preferred in terms of safety and reaction efficiency. Although there is no particular limitation, it is preferably 3 to 20 times the number of moles of the borane group, and more preferably 5 to 15 times the number of moles of the borane group.

To achieve alkaline conditions, it is preferable to use alkali metal hydroxides, alkaline earth metal hydroxides, etc., and among them, sodium hydroxide or canium hydroxide is more preferable. The amount added is preferably 176 to 3 times the number of moles of hydrogen peroxide used, and more preferably 1/4 to 2 times the number of moles of hydrogen peroxide used.

The reaction temperature is in the range of -10 to 100°C, but -10 to 100°C.
70°C is preferred, and -10 to 50°C is more preferred.

The reaction time is preferably 30 minutes or more after adding hydrogen peroxide,
Less than 3 hours is sufficient.

In addition, after the hydroporation reaction between the copolymer (c) and the poran compound, the oxidation reaction described above is subsequently performed without isolating the produced borane-modified polymer to induce it into an alcoholic hydroxyl group. You can also do 1.

(2) Modified olefin resin The olefin resin used in the present invention is a homopolymer such as ethylene, propylene, butene-1,3-methylbutene-1,4-methylpentene-1, or a majority weight of these. It is a copolymer consisting of

In particular, crystalline propylene polymers, i.e. crystalline propylene homopolymers, crystalline propylene-ethylene or propylene-butene-1 random copolymers, or crystalline propylene-ethylene or propylene-butene-1
A one-block copolymer is preferred, and it further contains an olefin resin containing a polyunsaturated compound such as dialkenylbenzene, methyloctadiene or methylhexadiene as a copolymerization component.

Examples of unsaturated carboxylic acids or derivatives thereof that can be used to modify olefinic resins include acrylic acid, methacrylic acid, malic acid, itaconic acid, citraconic acid, fumaric acid, hymic acid, crotonic acid, Mesaconic acid, sorbic acid, or their esters, acid anhydrides, metal salts, amides, imides, etc., among which acrylic acid, methacrylic acid, and maleic anhydride are preferred;
Two or more of these can also be used in combination.

The amount of the unsaturated carboxylic acid or its derivative used is 0.1 to 300 parts, preferably 2 to 1 to 200 parts, per 100 parts by weight of the olefin resin (hereinafter referred to as parts). If the amount of unsaturated carboxylic acid or its derivative is less than 0.1 part, the improvement effect of the present invention will hardly be achieved, and if it exceeds 300 parts, the mechanical properties of the olefin resin will be difficult to exhibit.

The modified olefin resin used in the present invention is produced by subjecting an olefin resin together with an unsaturated carboxylic acid or its derivative to conventionally known radical graft polymerization conditions.
For example, a method of irradiating radiation such as γ-rays or electron beams while the olefin resin and the monomer coexist; a method of irradiating the olefin resin with radiation and then allowing the monomer to coexist;
Any method can be employed in the present invention, such as a method in which the olefin resin and the monomer are coexisting in a solution state, a molten state, or a dispersed state, and graft polymerization is carried out in the presence of a radical polymerization catalyst. As the radical polymerization catalyst, penzoyl peroxide, t-butyl peroxybenzoate,
Organic peroxides such as dicumyl peroxide, t-butyl hydroperoxide, 1-butylperoxyacetate, diisobrobyl peroxydicarbonate, 2,2-bis(1-butylperoxy)octane, methyl ethyl ketone peroxide, etc. Examples include inorganic peroxides such as potassium persulfide, azo compounds such as α,α'-azobisisobutyronitrile, and redox catalysts such as hydrogen peroxide and ferrous salts. These radical polymerization catalysts are appropriately selected depending on the polymerization method, and one type or two or more types can also be used in combination. The temperature of the radical graft polymerization reaction is usually 30 to 350°C, preferably 50 to 350°C.
The temperature is in the range of 300°C, and the polymerization time is in the range of 30 seconds to 50 hours, preferably 1 minute to 24 hours. The amount of the radical polymerization catalyst to be used is appropriately selected from the range of 0 to 100 parts, preferably 0 to 30 parts, based on 100 parts of the olefin resin.

(3) Graft copolymer The graft copolymer is produced by a reaction between the alcoholic hydroxyl group of the alcoholic hydroxyl group-modified copolymer and the unsaturated carboxylic acid or its derivative introduced into the modified olefin resin.

The reaction temperature of this reaction is 0 to 400°C, preferably 0 to 400°C.
The 6 reactions at 300°C may be either solution reactions or melt reactions. In solution reactions, benzene, toluene, xylene, etc. are used as solvents, but are not particularly limited. Also, during the reaction, An acid, a base, etc. may be added as a catalyst.

The graft copolymer of the present invention can be separated and
It can be subjected to processing such as purification.

(Examples) Hereinafter, the present invention will be explained in detail with reference to Examples, but the scope of the present invention is not particularly limited thereby.

Production Example 1: Production of Alcoholic Ice Hydroxyl Group-Modified Copolymer (1) 5 g of a commercially available styrene-butadiene block copolymer (styrene copolymerization amount 60% by weight, product 82 TR2400, manufactured by Nippon Synthetic Rubber ■) was sufficiently prepared. 300 dried and replaced with nitrogen
TId! 101 ml of tetrahydrofuran, which was placed in a three-ring flask and thoroughly dehydrated and purified with lithium aluminum hydride.
d was added and stirred at room temperature to completely dissolve the styrene-butadiene block copolymer. This solution was cooled to 0°C, and 11,4 mmol of 9-BBN was added to it under a nitrogen stream.
The reaction mixture was stirred for hours. Then sodium hydroxide 0.
Add 90g and 1.55wI of 30% hydrogen peroxide solution,
After further stirring at 0°C for 1 hour, the temperature was raised to 40°C and the reaction was stirred for 1 hour. After the reaction was completed, the solution was diluted with methanol 1j2.
to precipitate the hydroxyl group-modified copolymer. The precipitated hydroxyl group-modified copolymer was filtered with suction and then dried. Yield is 4
．． It was 9g.

When this hydroxyl group-modified copolymer was analyzed by NMR,
The content of alcoholic hydroxyl groups is 0.8 tamol/1
g copolymer. The obtained copolymer is referred to as an alcoholic hydroxyl group-modified copolymer (1).

Production Example 2: Production of Alcoholic Ice Hydroxyl Group-Modified Copolymer (2) 5 g of a commercially available styrene-butadiene block copolymer (styrene copolymerization amount 15% by weight, trade name: TR2900, manufactured by Nippon Synthetic Rubber ■) was sufficiently prepared. 300 dried and nitrogen-substituted
- Tetrahydrofuran 1001d, which was placed in a three-ring flask and thoroughly dehydrated and purified with lithium aluminum hydride! was added and stirred at room temperature to completely dissolve the styrene-butadiene block copolymer. Cool the solution to 0°C and
-BBN was added at 40.8 mmol and stirred for 1 hour under a nitrogen stream to react. After that, 1.63g of sodium hydroxide
Add 13.9 J of 30% by weight hydrogen peroxide solution and heat at 0°C.
After stirring for an hour, the temperature was raised to 40°C, and the mixture was further stirred for 1 hour to react. After the reaction was completed, the solution was poured into methanol to precipitate the hydroxyl group-modified copolymer. The precipitated hydroxyl group-modified copolymer was filtered with suction and then dried. Yield was 5.1g.

When this hydroxyl group-modified copolymer was analyzed by NMR,
The content of alcoholic hydroxyl groups is 1.4 mmol/l g
It was a copolymer. The obtained copolymer is referred to as an alcoholic hydroxyl group-modified copolymer (2).

Production Example 3: Production of modified olefin resin (1) Copolymer of propylene and 7-methyl-1,6-octadiene (7-methyl-1,6-octadiene content 2 mol%, crystals determined by X-ray diffraction method) 46.5%, ASTM
250g of melt flow rate (MFR 2g/10min) at 230°C measured in accordance with D1238 and 250g of maleic anhydride were placed in a 10β glass flask equipped with a stirrer that had been sufficiently purged with nitrogen in advance, Chlorobenzene 5β was added and dissolved by heating and stirring at 110°C. To this solution, 0.6 g of benzoyl peroxide dissolved in chlorobenzene 500- was added dropwise over 2 hours.
After the dropwise addition was completed, the reaction was further carried out at 110°C for 3 hours. The obtained reaction product was poured into 150ml of acetone, and the product was precipitated and washed twice, followed by drying under reduced pressure to obtain a modified copolymer. The maleic anhydride content of this modified copolymer was determined by infrared spectroscopy to 4.
2% by weight, MFR was 2.8 g/10 min. The obtained resin is referred to as modified olefin resin (1).

Production Example 4: Production of modified olefin resin (2) Propylene homopolymer powder (MFR at 230°C: I
g/10 minutes) and 50 g of maleic anhydride were placed in a glass flask equipped with a stirrer at 1.
The mixture was heated and stirred at °C to dissolve. Add 5 xylene to this l@ solution.
25g of benzoyl peroxide dissolved in 00-
It was added dropwise over a period of time, and after the completion of the dropwise addition, the reaction was further carried out at 110°C for 3 hours. 6. The reaction product obtained was poured into acetone at 15°C, and the product was precipitated and filtered and washed twice. After that, the mixture was dried under reduced pressure to obtain a modified propylene resin. The maleic anhydride content of this modified propylene resin is
0.67% by weight by infrared spectroscopy, MFR is 7-7
g/10 minutes, the obtained resin is referred to as modified olefin resin (2).

Production Example 5: Production of modified olefin resin (3) As a catalyst, a propylene resin having a double bond at the terminal (number average molecular weight: 8
．． 100 (polystyrene equivalent value) and 25 g of maleic anhydride were placed in a 1 g autoclave equipped with a stirrer that had been sufficiently purged with nitrogen in advance, and 50 g of decane was added. ' was added and reacted at 200°C for 8 hours. The obtained reaction product was poured into acetone at 5° C., and the product was precipitated and filtered and washed twice, followed by drying under reduced pressure to obtain a modified propylene resin. Yield was 48.2g. The maleic anhydride content of this modified propylene resin was determined by NMR measurement to be 0.0], 1% by weight. The obtained resin is referred to as a modified olefin resin (3).

Example 1 3 g of alcoholic hydroxyl group-modified copolymer (1), 3 g of modified olefin resin (1) and 0 p-toluenesulfonic acid
．． 12 g was charged into a 300 mt' flask, and xylene 120- was added thereto, and the reactant was reacted for 5 hours while refluxing the xylene. The reactant was poured into methanol II2, and the product was filtered and dried under reduced pressure. The amount of polymer obtained was 5.9 g. This polymer was subjected to Soxhlet extraction with tetrahydrofuran for 5 hours to remove unreacted modified copolymer, resulting in 4.7 g of graft copolymer. Infrared spectroscopic analysis revealed that the content of the alcoholic hydroxyl group-modified copolymer (1) in this graft copolymer was 36.2% by weight.

Example 2 Modified olefin resin (
The same procedure as in Example 1 was carried out except that 3) was used. The amount of polymer obtained was 5.8 g. This polymer was subjected to Soxhlet extraction with tetrahydrofuran for 5 hours to remove unreacted modified copolymer, and as a result, 5.1 g of graft copolymer was obtained. Infrared spectroscopic analysis revealed that the content of the alcoholic hydroxyl group-modified copolymer (1) in this graft copolymer was 412% by weight.

Example 3 25 g of alcoholic hydroxyl group-modified copolymer (2) and 25 g of modified olefin resin (2) were heated for 6 minutes at 230° C. and 60 rpm in a Toyo Seiki blast mill with an internal volume of 60 mm. It was melted and kneaded. The obtained resin was subjected to Soxhlet extraction with tetrahydrofuran for 5 hours to remove unreacted modified copolymer, and as a result, 3.6 g of graft copolymer was obtained. Infrared spectroscopic analysis revealed that the content of the alcoholic hydroxyl group-modified copolymer (2) in this graft copolymer was 16.7% by weight.

Application example Propylene resin (manufactured by Mitsubishi Yuka ■, product name: TAB) and poly(2,6-cymethyl-1,4-phenylene ether)
(manufactured by Nippon Polyether Co., Ltd., intrinsic viscosity 0.4 df!/g measured in chloroform at 30°C), the graft copolymer obtained in Example 2, and the commercially available styrene-butadiene block copolymer (styrene copolymer 60% by weight, trade name TR2400, manufactured by Japan Synthetic Rubber ■) with the composition shown in Table 1, in a blast mill manufactured by Toyo Seiki Co., Ltd. with an internal volume of 60 mm.
The mixture was melt-kneaded at 280° C. for 6 minutes at 5 rotations and 60 rpm.

The physical properties of the obtained thermoplastic resin composition were evaluated as follows, and the results are shown in Table 1.

(1) Flexural modulus Using a test piece with a width of 25 mm and a length of 80 mm+, JISK
It was measured using an Instron testing machine in accordance with 7203.

(2) Izot impact strength According to JIS K7110, the unnotched Izot impact strength at 23° C. was measured by stacking three test pieces of two thicknesses.

(Effects of the Invention) As is clear from Table 1, the thermoplastic resin composition using the graft copolymer according to the present invention exhibits high mechanical strength, particularly excellent impact resistance improvement effects.

Claims (1)

[Scope of Claims] A copolymer (c) having both a polymer chain (a) mainly composed of an alkenyl aromatic compound and a polymer chain (b) mainly composed of a conjugated diene compound in the same molecule. , General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (I) (In the formula, Z^1 and Z^2 each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a hydrocarbon oxy group, or a halogen atom. ) A modified olefin in which an unsaturated carboxylic acid or a derivative thereof is introduced into an alcoholic hydroxyl group-modified copolymer obtained by reacting a borane compound having at least one boron-hydrogen bond represented by the formula and then oxidizing the boron bonding site. A method for producing a graft copolymer, which comprises reacting a system resin.