JPH04145125A - Production of terminal carboxylic acid-modified polyphenylene ether - Google Patents

Abstract

PURPOSE:To obtain the subject ether with enhanced compatibility with modified polyolefins and impact strength useful as a material for engineering plastics by reacting a specific polyphenylene ether with a benzyl halide derivative. CONSTITUTION:(A) A polyphenylene ether expressed by formula I (Q<1> is halogen, primary or secondary alkyl, phenyl, etc.; Q<2> is H, halogen, primary or secondary alkyl or phenyl; n is >=10) is reacted with (B) a benzyl halide derivative expressed by formula II (R<1> and R<2> are H or 1-6C hydrocarbon; R<3> is direct bond or 1-32C bifunctional hydrocarbon; Y is OH or reactive residue of carboxyl group; X is halogen; m is 1-5) to afford the objective ether expressed by formula III.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing terminal carboxylic acid-modified polyphenylene ether by modifying the terminal phenolic hydroxyl group of polyphenylene ether.

Compared to unmodified polyphenylene ether, the terminal carboxylic acid-modified polyphenylene ether produced by the production method of the present invention reacts with the functional groups of the blended resin to increase the compatibility between the resins and improve 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.

(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. However, this resin has a high melt viscosity due to its high glass transition temperature, which results in poor moldability and poor impact resistance as an engineering plastic. It has the following disadvantages.

Blending with polyolefins or other engineering plastics has been carried out with the aim of improving these shortcomings, but the two polymers are inherently poorly compatible and the resulting compositions are brittle and have poor mechanical properties. The strength and impact strength are reduced and it cannot be put 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 the terminal phenolic hydroxyl group 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-
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 (Journa
l of Polymer 5science: Par
(see AP Polymer Chemistry, 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.

In addition, a method for acid-modifying the end groups of polyphenylene ether using trimellidic anhydride chloride was disclosed in Japanese Patent Application Laid-Open No. 62-1999.
Although it is disclosed in Japanese Patent No. 43455, it uses acid chloride, which is corrosive to metals, and because the functional groups are connected by ester bonds, there are problems such as easy hydrolysis.

(Problems to be Solved by the Invention) The present invention provides an extremely easy method for producing terminal carboxylic acid-modified polyphenylene ether that can form a composition with good compatibility with resins such as modified polyolefins, polyesters, and polyamides. With the goal.

(Means for Solving the Problems) The present inventors have discovered that by modifying polyphenylene ether (the D-terminal phenolic hydroxyl group using a halogenated benzyl derivative), polyphenylene ether modified with a terminal carboxylic acid can be easily produced compared to conventional methods. They discovered that ether can be obtained and completed the present invention.

The present invention is based on the general formula (wherein Q' each represents a halogen atom, a secondary or secondary alkyl group, a phenyl group, an aminoalkyl group, a hydrocarbonoxy group, or a heterohydrocarbonoxy group, and Q2 is (each represents a hydrogen atom, a halogen atom, a primary or secondary alkyl group, a phenyl group, a haloalkyl group, a hydrocarbonoxy group, or a helohydrocarbonoxy group, and n represents a number of 10 or more) to the ether, - formula (wherein R' and R2 are each a hydrogen atom or a carbon number of 1 to 6
represents a hydrocarbon group, R3 is a direct bond or has 1 to 3 carbon atoms
represents a divalent hydrocarbon group of characterized by reacting a benzyl derivative with the general formula (wherein Q', Q2, R1, R2, R3, Y, m and n
is the same as above) This is a method for producing terminal carboxylic acid-modified polyphenylene ether.

The polyphenylene ether used in the present invention has the formula - It is a homopolymer or copolymer having the structure.

Suitable examples of primary alkyl groups for Q' and Q2 are methyl, ethyl, n-propyl, n-butyl, n-amyl, isoamyl, 2-methylbutyl, n-hexyl, 2,3-
Dimethylbutyl, 2-13- or 4-methylpentyl or heptyl. Suitable examples of secondary alkyl are:
Isopropyl, 5ec-butyl or 1-methylpentyl. In most cases Q' is an alkyl or phenyl group, especially an alkyl group having 1 to 4 carbon atoms, and Q2 is a hydrogen atom. A suitable polyphenylene ether homopolymer is, for example, one consisting of 2,6-dimethyl-1,4-phenylene ether units. Suitable copolymers include the above units and 2.3.6-h rimel-1.4-
It is a random copolymer consisting of a combination of phenylene ether units. Many suitable homopolymers and random copolymers are described in the patent literature. Polyphenylene ethers containing molecular moieties that improve properties such as, for example, molecular weight, melt viscosity and/or impact strength are 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 usually corresponds to an intrinsic viscosity of about 0.2 to 0.88/g at 30°C in chloroform.

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, those containing at least one heavy metal compound such as copper, manganese, cobalt, etc., usually in combination with various other substances.

General formula (III) used for modification of polyphenylene ether
) is a compound having at least one halogenated benzyl group and at least one carboxyl group. Here, X represents a halogen atom, specifically fluorine, chlorine, bromine, iodine, etc.

Preferred specific examples of halogenated benzyl derivatives include:
p-Chloromethylphenylacetic acid, p-promedylphenylacetic acid, 4-chloromethylbenzoic acid, 4-bromomethylbenzoic acid, 4-chloromethylphthalic anhydride, 3-chloromethylphthalic anhydride
Examples include chloromethylphthalic acid.

The terminal carboxylic acid-modified polyphenylene ether represented by the general formula (I) produced in the present invention is produced by combining the polyphenylene ether represented by the -41 formula (II) and the halogenated benzyl derivative represented by the general formula (rlI) in the presence of a basic catalyst. There is tU
By reacting in a medium, or in a mixed solvent of an organic solvent in which polyphenylene ether can be dissolved and an aqueous solution of a water-retaining inorganic basic catalyst, in the presence of a phase transfer catalyst,
It can be easily produced by reacting polyphenylene ether with a halogenated benzyl derivative.

The organic solvent used here is desirably capable of dissolving polyphenylene ether. Specifically, aromatic solvents such as benzene, toluene, and xylene; halogenated aromatic solvents such as chlorobenzene and dichlorobenzene; halogenated hydrocarbon solvents such as chloroform, trichloroethylene, and carbon tetrachloride, etc. .

Examples of the basic catalyst include alcoholades such as sodium methoxide and sodium ethoxide.

Benzyldimethylamine, triethylamine, tributylamine, 1,8-diazabicyclo[5,4,0]-7
-Tertiary amines such as undecene (DBU) can be mentioned. Examples of water-soluble inorganic basic catalysts include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkali metal carbonates such as sodium carbonate and potassium carbonate.

Examples of the phase transfer catalyst include quaternary ammonium salts, quaternary phosphonium salts, and tertiary sulfonium salts. Preferred are quaternary ammonium salts, specific examples of which include benzyltrimethylammonium chloride, benzyltriethylammonium chloride, benzyltributylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium hydrogen sulfate, or trioctylmethylammonium. Examples include chloride.

In this reaction, 1 mole of the terminal phenolic hydroxyl group of polyphenylene ether is treated with 1 mole of the modifier represented by the formula (III).
~30 moles are used, preferably 2 to 20 moles. The organic solvent is 3 parts by weight per 100 parts by weight of polyphenylene ether.
00 to 1000 parts by weight are used. The basic catalyst contains 1=lO equivalent per equivalent of modifier used, preferably 1
~3 equivalents are used. The phase transfer catalyst is used in an amount of 1 to 10 parts by weight per 100 parts by weight of polyphenylene ether.

To explain the specific manufacturing procedure of terminal carboxylic acid-modified polyphenylene ether (I), polyphenylene ether (
]T) in an organic solvent by heating and then adding a basic catalyst, or adding a water droplet of an inorganic basic catalyst and a phase transfer catalyst, and increasing the temperature from room temperature to a temperature that does not exceed the boiling point of the organic solvent used. It is produced by adding a halogenated benzyl derivative, which is a modifier, to react at high temperature, and then heating and stirring until the reaction is completed.

(Example) 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 d!!/g).

The reaction rate of the terminal phenolic hydroxyl group of polyphenylene ether was reported in the Journal of Applied Polymer Science Near Bride Polymer Symposium (Jo
Urnal of Applied Polymer 5
Science: Applied Polymer S
ymposiuml, vol. 34 (1978), 103-
The calculation was performed by quantifying the terminal phenolic hydroxyl groups before and after the reaction according to the method described on page 117.

Example 1 20.0 g of polyphenylene ether and 200 g of toluene
ml was charged into a reactor and heated and stirred at 80°C to dissolve polyphenylene ether. Subsequently, after adding 1.5 g of sodium ethoxide as a basic catalyst, the temperature of the reaction mixture was raised to 90° C. and stirring was continued for 30 minutes. While maintaining this temperature, 5.1 g of p-bromomethylphenylacetic acid was added over 15 minutes. Furthermore, after heating and stirring for 7 hours, the reaction mixture was poured into 1.5 f2 of methanol to precipitate the produced modified resin. This was washed separately with condensed water at 1°C, and then washed with methanol 11°C.
The mixture was dried under reduced pressure at °C to obtain terminal carboxylic acid-modified polyphenylene ether. The yield is 100%, and the reaction rate of the terminal phenolic hydroxyl group of polyphenylene ether is 303%.
Met.

Example 2 200g of polyphenylene ether and 200w of toluene
11 was charged into a reactor and heated and stirred at 80°C to dissolve polyphenylene ether. Subsequently, 5.0 g of a 50% aqueous sodium hydroxide solution was added as a basic catalyst, and 10 g of trioctylmethylammonium chloride was further added, the temperature of the reaction mixture was raised to 90° C., and stirring was continued for 30 minutes.

While maintaining this temperature, 3.8 g of an aqueous solution of 4-chloromethylbensikoic acid was added over 15 minutes.

Thereafter, the same treatment as in Example 1 was carried out to obtain terminal carboxylic acid-modified polyphenylene ether. The yield was 94.9%, and the reaction rate of the terminal phenolic hydroxyl group of polyphenylene ether was 98.8%.

FIG. 1 shows the infrared absorption spectrum of a cast film prepared from a chloroform solution of the obtained terminal carboxylic acid-modified polyphenylene ether. 1700cm-'
Absorption presumed to be due to the carbonyl group of the carboxyl group was observed nearby.

Example 3 The temperature of the reaction mixture was 88°C, and as a modifier, 5
．． A terminal carboxylic acid-modified polyphenylene ether was obtained in the same manner as in Example 2 except that 0 g of aqueous p-bromomethylphenylacetic acid was used. Yield is 100%
The reaction rate of the terminal phenolic hydroxyl group of polyphenylene ether was 80.3%.

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 62.0'00, weight average molecular weight 450.0
00, hydroxyl group content 05% by weight) and 0.1 g of aluminum isopropoxide as a reaction catalyst were dissolved in xylene 1001111 and heated under reflux for 7 hours under a nitrogen atmosphere.

After the reaction was completed, the reaction mixture was poured into methanol II2,
The reacted polymer was precipitated. After cleaning the mold with methanol at 1℃, it was heated and dried under reduced pressure at 80℃.6
．． 0g of polymer was recovered.

Next, 1.646 g of the obtained polymer was added to chloroform 2
Soxhlet extraction was performed for 7 hours using 00+al' as a solvent, and the polyphenylene ether that did not undergo the graft reaction was extracted and removed. As a result, it was found that the amount of polyphenylene ether extracted and removed was 0.595 g, and the content of polyphenylene ether in the graft body was 217% by weight.

(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;
This can also easily be treated with polypropylene, as shown in Application Example 1.

We were able to perform a graft connection.

[Brief explanation of drawings]

FIG. 1 shows the infrared absorption spectrum of the terminal carboxylic acid-modified polyphenylene ether obtained in Example 2 (cast film prepared by dissolving in chloroform).

Claims (1)

[Claims] General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (II) (In the formula, Q^1 is each a halogen atom, a primary or secondary alkyl group, a phenyl group, an aminoalkyl group, Represents a hydrocarbon oxy group or a halohydrocarbon oxy group, Q^2
each represents a hydrogen atom, a halogen atom, a primary or secondary alkyl group, a phenyl group, a haloalkyl group, a hydrocarbonoxy group, or a halohydrocarbonoxy group, and n represents a number of 10 or more) Ether has a general formula▲mathematical formula, chemical formula, table, etc.▼(III) (In the formula, R^1 and R^2 are each a hydrogen atom or a carbon number of 1
~6 hydrocarbon group, R^3 represents a direct bond or a divalent hydrocarbon group having 1 to 32 carbon atoms, Y represents a reactive residue of an OH group or a carboxyl group, and X is a halogen atom (where m represents an integer from 1 to 5) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) (In the formula, Q^ 1, Q^2, R^1, R^2, R^3, Y
, m and n are the same as above) A method for producing a terminal carboxylic acid-modified polyphenylene ether.