JPH04261426A - Production of terminal carboxyl-modified polyphenylene ether - Google Patents

Abstract

PURPOSE:To obtain the subject terminal carboxyl-modified polyphenylene ether having an improved compatibility with a resin such as a modified polyolefin or a polyester by making a polyphenylene ether functional. CONSTITUTION:A terminal-epoxidized polyphenylene ether represented by formula I [Q<1> is halogen, primary or secondary alkyl group, etc.; Q<2> is H, halogen, etc.; R is divalent fatty, alicyclic, heterocyclic or (substituted)aromatic hydrocarbon; n>=10] is reacted with a polycarboxylic acid (e.g. maleic acid or fumaric acid) in an organic solvent (e.g. benzene or toluene) at a temperature within a range of room temperature-200 deg.C, preferably 50-150 deg.C, thus giving the objective terminal carboxyl-modified polyphenylene ether having a molecular structure of formula II (A is polyphenylene ether residue; B is polycarboxylic acid residue).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing terminal carboxylic acid-modified polyphenylene ethers by functionalizing polyphenylene ethers.

Compared to unfunctionalized polyphenylene ether, the terminal carboxylic acid-modified polyphenylene ether of the present invention reacts with the functional groups of the blended resin when blended with other resins, thereby increasing the compatibility between the resins. This has the effect of increasing the impact strength of the composition, and is also useful as a precursor for graft or block copolymers.

0003

[Prior Art] Polyphenylene ether is an extremely useful thermoplastic resin with excellent heat resistance, mechanical properties, electrical properties, water resistance, acid resistance, alkali resistance, and self-extinguishing properties, and is used as an engineering plastic material. , many applications are being developed. However, this resin has a high melt viscosity due to its high glass transition temperature, and therefore has disadvantages such as poor moldability and poor impact resistance as an engineering plastic.

Blends with polyolefins or other engineering plastics have been carried out with the aim of improving these drawbacks, but the two polymers are inherently poorly compatible and the resulting compositions are brittle and difficult to machine. The mechanical strength and impact strength are reduced, making it impossible to put it to practical use. Compatibilizers have been used to solve this problem, and most compatibilizers are graft or block copolymers of both polymers. When synthesizing these copolymers, it is conceivable to react the terminal phenolic hydroxyl group of polyphenylene ether with a functional group in another polymer.

However, the types of functional groups of other polymers that can react with phenolic hydroxyl groups are limited, and the scope of their use is naturally limited. Therefore, many terminal group-modified polyphenylene ethers have been proposed for the purpose of increasing the reactivity of polyphenylene ethers.

As a method for modifying polyphenylene ether with carboxylic acid, a method of modifying polyphenylene ether with an acid anhydride or carboxylic acid having an unsaturated bond, preferably maleic anhydride, is disclosed in JP-A-56-26913 and JP-A-56-269-1. No. 49753 and other publications.

It has been reported that carboxylic acid-modified polyphenylene ether produced by these methods has an unsaturated bond of the modifier added to the main chain of the polyphenylene ether (
Journal of Polymer Science
e: Part A: Polymer Chem
istry, vol. 27, p. 3371, 1989). Furthermore, modification of polyphenylene ether by these methods requires reaction at high temperatures or in the presence of radicals, which causes problems such as deterioration of polyphenylene ether, and there are still many problems to be solved.

[0008] Furthermore, a method of acid-modifying the terminals of polyphenylene ether using trimellitic anhydride chloride is disclosed in JP-A-62-43455, but there is a problem in that it uses acid chloride which is corrosive to metals. be.

[0009]

[Problems to be Solved by the Invention] An object of the present invention is to provide an extremely easy method for producing terminal carboxylic acid-modified polyphenylene ether that can improve compatibility with resins such as modified polyolefins, polyesters, and polyamides. do.

0010

[Means for Solving the Problems] The present inventors have discovered that by reacting polyphenylene ether with an epoxidized terminal with a polycarboxylic acid, a terminal carboxylic acid-modified polyphenylene ether can be produced extremely easily compared to conventional methods. They discovered what they could do and completed the present invention.

That is, the present invention provides general formula (I)

00
12]

[Case 2]

(In the formula, Q1 each represents a halogen atom, a primary or secondary alkyl group, an alkenyl group, a phenyl group, an aminoalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group, and each Q2 represents a hydrogen atom) Represents an atom, a halogen atom, a primary or secondary alkyl group, a phenyl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group.R is a divalent aliphatic, alicyclic, or heterocyclic group. or a substituted or unsubstituted aromatic hydrocarbon group, where n represents a number of 10 or more) is reacted with a polycarboxylic acid to produce a terminal carboxylic acid-modified polyphenylene ether. .

Polyphenylene ether The polyphenylene ether used in the present invention has the general formula (
II)

[0015]

[Chemical formula 3]

(In the formula, Q1 each represents a halogen atom, a primary or secondary alkyl group, an alkenyl group, a phenyl group, an aminoalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group, and each Q2 represents a hydrogen atom,
a homopolymer having a structural unit of a halogen atom, a primary or secondary alkyl group, a phenyl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group, where n is a number of 10 or more; or It is a copolymer.

Suitable examples of primary alkyl groups include methyl,
Ethyl, n-propyl, n-butyl, n-amyl, isoamyl, 2-methylbutyl, n-hexyl, 2,3-dimethylbutyl, 2-, 3- or 4-methylpentyl or heptyl. Suitable examples of secondary alkyl groups are:
Isopropyl, sec-butyl or 1-methylpentyl. In most cases, Q1 is an alkyl group or a phenyl group, especially an alkyl group having 1 to 4 carbon atoms, and Q2 is a hydrogen atom. Suitable polyphenylene ether homopolymers include, for example, 2,6-dimethyl-1,4-
It consists of phenylene ether units. Suitable copolymers include the above units and 2,3,6-trimethyl-
It is a random copolymer consisting of a combination of 1,4-phenylene ether units. Many suitable homopolymers and random copolymers are described in the patent literature. For example, polyphenylene ethers containing molecular moieties that improve properties such as molecular weight, melt viscosity and/or impact strength may also be used.
It is also suitable. Examples include polyphenylene ether, in which a vinyl monomer such as a vinyl aromatic compound such as acrylonitrile or styrene, or a polymer such as polystyrene or an elastomer is grafted onto polyphenylene ether.

The molecular weight of polyphenylene ether is usually such that the intrinsic viscosity at 30° C. in chloroform is 0.2 to 0.8 d.
This corresponds to about 1/g.

Polyphenylene ethers are usually produced by oxidative coupling of the monomers mentioned above, and a number of catalyst systems are known for this oxidative coupling polymerization. There are no particular restrictions on the selection of the catalyst, and any known catalyst can be used.

For example, it contains at least one heavy metal compound such as copper, manganese, cobalt, etc., usually in combination with various other substances.

Method for producing terminally epoxidized polyphenylene ether Epoxidation of the terminal group of polyphenylene ether is described in, for example, JP-A-63-125525 and JP-A-2-6.
4127 and Japanese Patent Publication No. 63-503388.

The terminally epoxidized polyphenylene ether can be obtained by contacting the polyphenylene ether with an epoxy compound under heating.

As a specific method, if the epoxy compound is liquid at the reaction temperature and can dissolve polyphenylene ether, the epoxy compound can be used as both a solvent and a reactant. In addition, if the epoxy compound is solid at the reaction temperature or the epoxy compound does not dissolve the polyphenylene ether, a solvent that is a good solvent for both the polyphenylene ether and the epoxy compound and does not participate in the reaction, such as benzene, An aromatic hydrocarbon solvent such as toluene; a halogenated hydrocarbon solvent such as chloroform; or a halogenated aromatic hydrocarbon solvent such as chlorobenzene or dichlorobenzene is added.

[0024] The epoxy compound is preferably an epoxy compound having a halide at one end or an epoxy compound at both ends.
epichlorohydrin, 2-methylepichlorohydrin,
Epoxychlorotriazine and the like are preferred, and as a double-terminated epoxy compound, 2,2-bis(4-glycidylphenyl ether)propane and epoxy resin are preferred. Alternatively, terminal epoxidized polyphenylene ether can be obtained by reacting terephthalic acid chloride and glycidol.

The quantitative ratio of the epoxy compound used for terminal epoxidation to the polyphenylene ether is at least 1.0 times, preferably at least 2.0 times, the number of moles of the epoxy group relative to the terminal phenolic hydroxyl group of the polyphenylene ether.

The basic compounds used to promote the reaction are not particularly limited in type, but include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; alcoholates such as sodium methoxide and sodium ethoxide. etc. are preferred. The amount added is 1.0 equivalent or more, preferably 1.2 equivalent or more, particularly preferably 1.5 equivalent or more relative to the epoxy compound.

The reaction temperature is preferably around 80 to 120°C, and the reaction time is usually about 1 to 8 hours.

After the reaction, the system is cooled and the reaction mixture is poured into a poor solvent for polyphenylene ether, such as methanol, to precipitate the polyphenylene ether with epoxidized terminals.

After the reaction, the precipitate is filtered and then washed with water and methanol to remove unreacted epoxy compounds and alkali compounds. After washing, the precipitate is filtered out and 80~
It is dried at 110° C. under reduced pressure or normal pressure to obtain terminally epoxidized polyphenylene ether.

Polycarboxylic Acid The polycarboxylic acid used in the present invention is preferably a compound having at least two carboxyl groups in the same molecule.

Examples of suitable polycarboxylic acids include maleic acid, fumaric acid, maleic anhydride, succinic acid, succinic anhydride, phthalic acid, phthalic anhydride, glutamic acid, tartaric acid, trimellitic acid, trimellitic anhydride, citric acid. , malic acid, agaricic acid, meso-butene-1,2,3,4-
Examples include tetracarboxylic acid, 3-butene-1,2,3-tricarboxylic acid, 1,3,5-pentanetricarboxylic acid, tricarballylic acid, and 1,1,2,3-propanetetracarboxylic acid. These polycarboxylic acids may be used alone or in a mixture of two or more.

[0032] The terminal carboxylic acid-modified polyphenylene ether produced by the method of the present invention is prepared by mixing the terminal epoxidized polyphenylene ether represented by the general formula (I) and the polycarboxylic acid in an organic solvent at room temperature to 200°C, preferably 50 to 200°C. It can be easily produced by reacting in a temperature range of 150°C. Further, at this time, the reaction can be carried out in the presence of a catalyst that promotes the reaction of epoxy groups.

[0033] The organic solvent used here is desirably capable of dissolving the raw material polyphenylene ether. Specifically, aromatic hydrocarbon solvents such as benzene, toluene, and xylene; halogenated aromatic hydrocarbon solvents such as chlorobenzene and dichlorobenzene; halogenated hydrocarbon solvents such as chloroform, trichloroethylene, and carbon tetrachloride; N-methyl-2-pyrrolidone, 1,3-dimethyl-
Examples include aprotic polar solvents such as 2-imidazolidinone.

As a catalyst for promoting the reaction of epoxy groups, N, N
-dimethylaminopyridine, benzyldimethylamine,
Tertiary amines such as tributylamine and tris(dimethylamino)methylphenol; quaternary ammonium salts such as triethylbenzylammonium chloride and tetramethylammonium chloride; imidazole compounds such as 2-methyl-4-ethylimidazole and 2-methylimidazole; etc. is used.

[0035] 1.0 mol or more, preferably 2.0 mol or more of the polycarboxylic acid is used per 1 mol of the epoxy group of the terminally epoxidized polyphenylene ether. The organic solvent used in the production is used in an amount sufficient to completely dissolve the polyphenylene ether. The epoxy group reaction accelerator is used in an amount of 1 to 10% by weight of the terminally epoxidized polyphenylene ether used. Furthermore, the terminal carboxylic acid-modified polyphenylene ether produced by the method of the present invention is obtained by melt-kneading the terminal epoxidized polyphenylene ether represented by the general formula (I) and the polycarboxylic acid at a temperature of 200 to 390°C using a kneader or the like. It can also be manufactured by Also in this case, the reaction can be carried out in the presence of an epoxy group reaction promoting catalyst. The epoxy group reaction promoting catalyst used here, its usage amount, and the usage amount of polycarboxylic acid are the same as described above.

The structure of the terminal-carboxylic acid-modified polyphenylene ether produced in the present invention is expressed by the following formula (III
) has the molecular structure.

[0037]

[C4]

[0038]

[Examples] The present invention will be explained in detail below using examples.

The polyphenylene ether used in these examples was poly(2,6-dimethyl-1,4-phenylene ether) (PPE, intrinsic viscosity measured in chloroform at 30°C; 0.30 dl/g). be.

The reaction rate between the terminal phenolic hydroxyl group of polyphenylene ether and the epoxy compound and the carboxyl group of the terminal carboxylic acid-modified polyphenylene ether were confirmed by adding a 1.5% by weight carbon disulfide solution of polyphenylene ether to a quartz cell with an optical path length of 10 mm. This was carried out by measuring the infrared absorption spectrum using That is, the absorbance of the terminal phenolic hydroxyl group before and after the reaction (3,610
The reaction rate was calculated from the value of cm-1).

Production Example 1 5 liters of epichlorohydrin was added to 350 g of polyphenylene ether, and the mixture was stirred and dissolved at 100° C. under a nitrogen atmosphere. 70g of sodium ethoxide in this solution
and 300 ml of methanol were added over 20 minutes. Furthermore, stirring was continued at 100°C for 4 hours. After the reaction mixture was cooled to room temperature, 10 liters of methanol was added to precipitate the terminally epoxidized polyphenylene ether. After filtering this product, it was washed with 10 liters of methanol, further washed twice with 10 liters of pure water, and washed again with 10 liters of methanol. When the obtained terminal epoxidized polyphenylene ether was dried under reduced pressure at 80°C, 351 g was obtained.
Met.

When the terminal groups were quantified, it was found that 99% of the terminal phenolic hydroxyl groups of the raw material polyphenylene ether had reacted.

Examples 1 to 4 Terminal epoxidized polyphenylene ether 10 of Production Example 1
g, polycarboxylic acid listed in Table 1, and toluene 200ml
, N,N-dimethylaminopyridine (0.1 g) was charged into a reactor and heated and stirred for a predetermined period of time.

Thereafter, the resulting modified resin was poured into 1 liter of methanol to precipitate it. This was filtered and washed twice with 1 liter of methanol. The mixture was dried under reduced pressure at 90° C. to obtain terminal carboxylic acid-modified polyphenylene ether. Table 1 shows the absorption positions of carboxyl groups in the infrared absorption spectrum.

[0045]

[Table 1]

FIG. 1 shows the infrared absorption spectrum of a cast film prepared from a chloroform solution of the terminal carboxylic acid-modified polyphenylene ether obtained in Example 1.

[0047]

[Figure 1]

Application Example 1 3.0 g of terminal carboxylic acid-modified polyphenylene ether obtained in Example 2 and hydroxyl group-modified polypropylene (number average molecular weight 84,400, weight average molecular weight 419,000
, hydroxyl group content 5.25% by weight) and 0.1 g of para-toluenesulfonic acid were dissolved in 100 ml of xylene and heated under reflux for 7 hours under a nitrogen atmosphere.

After the reaction was completed, the reaction mixture was poured into 1 liter of methanol to precipitate the reacted polymer. After filtration, the polymer was further washed with 1 liter of methanol, and then dried under reduced pressure at 80° C., and 6.0 g of polymer was recovered.

Next, 1.56 g of the obtained polymer was subjected to Soxhlet extraction for 7 hours using 200 ml of chloroform as a solvent to extract and remove polyphenylene ether that had not undergone the graft reaction. As a result, the amount of polyphenylene ether extracted and removed was 0.619 g, and the content of polyphenylene ether in the graft polymer was found to be 17.1% by weight.

[0051]

Effects of the Invention As shown in the Examples, the method for producing terminal carboxylic acid-modified polyphenylene ether of the present invention is extremely easy, and as shown in Application Example 1, the method for producing polyphenylene ether modified with a terminal carboxylic acid is extremely easy. It can be easily grafted.

[Brief explanation of the drawing]

FIG. 1 is an infrared absorption spectrum of the terminal carboxylic acid-modified polyphenylene ether (cast film prepared from a chloroform solution) obtained in Example 1.

Claims (1)

[Claims] Claim 1: General formula (I) [Formula 1] (wherein, Q1 is each a halogen atom, a primary or secondary alkyl group, an alkenyl group, a phenyl group, an aminoalkyl group, a hydrocarbonoxy group, or a halo Represents a hydrocarbon oxy group, and Q2 is a hydrogen atom, a halogen atom, and
Represents a primary or secondary alkyl group, phenyl group, haloalkyl group, hydrocarbonoxy group or halohydrocarbonoxy group. R represents a divalent aliphatic, alicyclic, heterocyclic, or substituted or unsubstituted aromatic hydrocarbon group. n is 10
A method for producing a terminal carboxylic acid-modified polyphenylene ether, in which a terminal epoxidized polyphenylene ether represented by the above number is reacted with a polycarboxylic acid.