JPS5850605B2 - Method for producing graft copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a polyester polymer as a main chain, and uses acyloxystyrene, diacyloxystyrene (hereinafter referred to as acyloxystyrenes), hydroxystyrene, and dihydroxystyrene (hereinafter referred to as hydroxystyrene). The main chain is a graft copolymer or a polyester polymer grafted with a side chain mainly containing at least one of the above acyloxystyrenes and/or the above hydroxystyrenes and a polyene compound. This invention relates to a method for producing a graft copolymer co-grafted with main side chains.

One purpose of the present invention is to provide a method for producing a novel graft copolymer having excellent properties.Another purpose of the present invention is to improve the adhesiveness, dyeability, water absorption, gas permeability, and In addition to improving various properties such as oxidation resistance, flame retardance, and reactivity with other compounds, ion exchange fibers,
It can be used as ion exchange membranes, reverse osmosis membranes, pressure dialysis membranes, etc.

As a result of various studies for the above purpose, the present inventors have found that acyloxystyrenes and/or hydroxystyrenes can be graft-polymerized onto polyester polymers by so-called pre-irradiation method or simultaneous irradiation method using ionizing radiation. It has been found that mixtures of styrenes and/or hydroxystyrenes and polyene compounds can also be graft-polymerized onto polyester polymers in a similar manner.

The polyester polymer grafted with acyloxystyrenes and/or hydroxystyrenes of the present invention has poor adhesion, dyeability, water absorption, gas permeability, oxidation resistance, and compatibility with other compounds, which are disadvantages of polyester polymers. It is a completely new substance with improved reactivity and many useful uses, such as as a raw material for reactive polymers.

In addition, in the polyester polymer in which acyloxystyrenes and/or hydroxystyrenes and a polyene compound are co-grafted according to the present invention, the co-grafted polyene compound forms a partially cross-linked network structure, so that the polyene compound It has superior properties such as chemical resistance, heat resistance, and flame retardancy compared to those without graft polymerization.

Therefore, the gist of the present invention is to apply ionizing radiation to a polymer by adding a monomer mainly composed of acyloxystyrenes and/or hydroxystyrenes or a monomer mixture mainly composed of acyloxystyrenes and/or hydroxystyrenes and a polyene compound. A method for producing a graft copolymer, characterized by carrying out graft or co-graft polymerization using the present invention.

The polyester polymers used in the present invention include aliphatic polyesters such as polyethylene adipate and polybutylene sebacate, aromatic polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene isophthalate, polyto-4-phenylene sebacate, and polyto-4-phenylene sebacate. - Alicyclic polyesters such as cyclohexane cyclovinyl adipate are used.

These polymers may be in the form of powder, fiber, film, or any other form.

In addition, acyloxystyrenes to be subjected to graft polymerization,
That is, acyloxystyrene or diacyloxystyrene is represented by the general formula.

In the formula, n is 1 or 2, the position of the substituent can be arbitrarily selected, and R is a straight chain or branched aliphatic, alicyclic or aromatic hydrocarbon group having 1 to 20 carbon atoms. represent.

Specific examples of these include acetoxystyrene, diacetoxystyrene, fropionyloxystyrene, dipropionyloxystyrene, butyroyloxystyrene,
Examples include siftyroyloxystyrene, benzoyloxystyrene, dibenzoyloxystyrene, and the most commonly used are acetoxystyrene and diacetoxystyrene.

The hydroxystyrenes to be subjected to graft polymerization, ie, hydroxystyrene or dihydroxystyrene, may be any isomer having a different substituent position, or may be a mixture thereof.

Further, as the polyene compound to be subjected to graft polymerization, a compound containing two or more polymerizable double bonds in the molecule is used, such as divinylbenzene isoprene,
In addition to phtadiene, cyclopentadiene, ethylethenenorbornene, etc., polyhydric alcohol esters of acrylic acid or methacrylic acid, divinyl esters of adipic acid, etc. are used.

Among them, divinylbenzene and polyhydric alcohol ester of acrylic acid are preferably used.

Divinylbenzene has three isomers, ortho, meta, and para, and any of these isomers can be used, and a mixture of these is generally used.

Lucivinylbenzene, which is generally obtained as a commercial product, is often a mixture containing about 45% by weight of ethylvinylbenzene in addition to divinylbenzene, but this mixture may be subjected to the reaction as it is.

In the present invention, when a monomer mixture mainly composed of acyloxystyrenes and/or hydroxystyrenes and a polyene compound is co-grafted onto a polyester polymer, the acyloxystyrenes and the polyene compound are mixed as monomers for graft polymerization. Alternatively, hydroxystyrenes and a polyene compound may be mixed and subjected to the reaction, or acyloxystyrenes, hydroxystyrenes, and a polyene compound may be mixed and subjected to the reaction. good.

The mixing ratio of the acyloxystyrenes and/or hydroxystyrenes and the polyene compound can be selected arbitrarily, and the physical properties of the graft copolymer obtained will change depending on the mixing ratio, so the desired physical properties of the graft copolymer can be determined. The ratio should be selected depending on the conditions, but usually the ratio of acyloxystyrenes and/or hydroxystyrenes to the polyene compound is in the range of 200/1 to 1/1, and in the range of 50/1 to 2/1. is preferred.

These acyloxystyrenes and/or hydroxystyrenes or a mixture of them and a polyene compound are dissolved in an organic solvent and subjected to graft polymerization as a solution. Alternatively, an organic solvent can be used that uniformly dissolves both the polyene compound and the polyene compound.

For example, ketones such as acetone and methyl ethyl ketone, carboxylic acids such as formic acid and acetic acid, esters such as ethyl acetate and methyl acetate, alcohols such as methanol and ethanol, ethers such as tetrahydrofuran and dioxane, N-N-
Amides such as dimethylformamide and N-N-dimethylacetamide, aromatic L such as benzene and toluene, aliphatic or alicyclic hydrocarbons such as n-hepetane and cyclohexane, and mixed solvents thereof are suitable.

When the purpose is to graft to the inside of the polyester polymer used, it is desirable to use an organic solvent that swells the polymer.

A novel graft copolymer can also be obtained that can be grafted only on the surface.

The monomer concentration in the solution does not need to be particularly limited, but
．． A range of 1 to 80% by weight is suitable, and a range of 5 to 50% by weight is preferred.

The graft polymerization of the present invention is carried out using ionizing radiation.

Graft polymerization methods using ionizing radiation include a pre-irradiation method in which the main chain polymer is irradiated with ionizing radiation in the absence of the monomer to be grafted, and then the polymer is brought into contact with the monomer, and a method in which the monomer and polymer coexist. Although there is a simultaneous irradiation method in which ionizing radiation is irradiated below, either method may be used in the present invention.

As the ionizing radiation, various radiations such as r-rays, X-rays, electron beams, α-rays, or mixed radiations thereof can be used.

The intensity of the ionizing radiation used, that is, the dose rate, is approximately 10
3 to 1011 rad per hour is suitable.

For gamma radiation, dose rates of 105 to 106 rad/hour are usually advantageous, and for electron beams, dose rates as high as IO9 to 1011 rad/hour can be advantageously used.

The use of electron beams generated from an electron accelerator is particularly effective because it allows high-dose irradiation in a short period of time.

The total irradiation dose required for graft polymerization is usually 105 rand or more.

There is no need to particularly limit the temperature during the radiation irradiation in the pre-irradiation method, but if the temperature becomes too high, radicals will disappear, which is not very preferable, so the temperature during the irradiation is preferably room temperature or lower.

In carrying out the present invention, when using the pre-irradiation method, the polyester polymer is irradiated with ionizing radiation in a vacuum, nitrogen stream, or air to generate scavenged radicals or polymer peroxides in the polyester polymer. Then, the polyester polymer is immersed in an organic solvent solution containing acyloxystyrenes and/or hydroxystyrenes, or these and a polyene compound, so that monomers are absorbed into the scavenging radicals or polymer peroxide formation sites of the polyester polymer. Graft polymerized.

If a polyene compound is used, partial crosslinking of the resulting graft copolymer by the grafted polyene compound also occurs.

When irradiation with ionizing radiation is carried out in a vacuum or in a nitrogen stream, the graft polymerization reaction proceeds satisfactorily at room temperature or lower, and may also be carried out at a temperature higher than room temperature.

When irradiation with ionizing radiation is carried out in air, the graft polymerization reaction is preferably carried out at a temperature of 60°C or higher.

Industrially, a pre-irradiation method in air or in a nitrogen stream is advantageous.

In addition, when using the simultaneous irradiation method, the polyester polymer is immersed in an organic solvent solution containing acyloxystyrenes and/or hydroxystyrenes or these and a polyene compound, and ionizing radiation is irradiated onto the polyester polymer. Monomers are immediately graft-polymerized onto the radicals generated.

If a polyene compound is used, crosslinking by the grafted polyene compound also takes place, as in the pre-irradiation method.

Although room temperature is sufficient for the reaction temperature, it may be higher.

During graft polymerization, oxygen present in the monomer solution may inhibit the reaction, so it is preferable to reduce dissolved oxygen by a method such as nitrogen substitution.

The concentration of the acyloxystyrenes and/or hydroxystyrenes or the monomer mixture of these and a polyene compound to be subjected to the graft polymerization reaction can be changed as appropriate depending on the graft ratio required for the intended graft copolymer.

Further, the grafting ratio of the resulting graft copolymer does not need to be particularly limited, but from the viewpoint of modifying the polyester polymer, it is preferably 0.1% by weight or more.

The graft copolymer thus produced is washed with an organic solvent if necessary.

Furthermore, in the case of a graft copolymer having a side chain containing acyloxystyrenes, the acyloxy group in the side chain can be converted into a hydroxyl group by hydrolysis treatment, if necessary.

This hydrolysis treatment can be easily carried out under mild conditions.

That is, using an acid or a base as a catalyst, the graft copolymer is placed in an aqueous solution or a mixed solution of water and a water-soluble organic solvent containing these catalysts to carry out a hydrolysis reaction of the acyloxy groups in the side chains.

Since the hydrolysis reaction is mainly carried out in a heterogeneous system, a water-soluble organic solvent such as alcohol or ketone and water are used to increase the affinity between the substrate and the catalyst and to dissolve the organic acid released when an acidic catalyst is used. Preferably, it is carried out in a mixture with.

A suitable hydrolysis temperature is 50 to 100°C.

In this hydrolysis treatment, the hydrolysis rate of the acyloxy group in the side chain can be changed arbitrarily.

According to the present invention, the side chain mainly consists of acyloxystyrenes and/or hydroxystyrenes or these and a polyene compound, and when a polyene compound is used, the polyene compound contained in the side chain partially A novel graft copolymer having a crosslinked networked polyester polymer as its main chain can be obtained.

This graft copolymer has excellent adhesion, dyeability, water absorption, gas permeability, and oxidation resistance, which are the disadvantages of polyester polymers.
Graft copolymers with hydroxystyrene groups in their side chains have improved or newly developed flame retardancy or reactivity with other compounds, and these properties are excellent, making them useful for reactive polymers and ion-exchange fibers. , ion exchange membrane, reverse osmosis membrane,
It is a useful new substance that has many uses, such as as a raw material for pressure dialysis membranes.

The present invention will be further explained below with reference to Examples.

Example 1 A solution 701 of 50% by weight p-acetoxystyrene and 50% by weight methanol was placed in one leg of a glass H-shaped ampoule.
Add rLl and thoroughly degas it using the freeze-thaw method in a vacuum.

Insert a polyethylene terephthalate film (thickness 60μ, weight 1.194?) into the other leg and irradiate it with an electron beam of 10Mrad (acceleration voltage 2.0MeV, acceleration current 1.0yrLA) at room temperature in a nitrogen stream, and Make a vacuum.

After creating a sufficient vacuum, the monomer solution was transferred to the film side and reacted at 60° C. for 8 hours.

After the reaction, the ampoule was opened and the film was taken out, thoroughly washed with acetone, and dried under reduced pressure until it reached a constant weight.

The grafting rate calculated from the weight difference before and after the reaction was 75%.

This material did not change in weight even after repeated acetone extraction.

Example 2 45% by weight of p-acetoxystyrene and divinylbenzene (purity 55%,
(contains 5% ethylstyrene) 5% by weight, methanol 50%
A solution of 701 rLl of % by weight was added and thoroughly degassed by freeze-thaw method under vacuum.

A polyethylene terephthalate film (thickness 60μ, weight 1.198S') irradiated with 10Mrad of electron beam (acceleration voltage 2.0MeV, acceleration current 1.0mA) at room temperature in a nitrogen stream was placed in the other leg, and the film was heated sufficiently. Make a vacuum.

After creating a sufficient vacuum, the monomer solution was transferred to the film side and reacted at 60° C. for 6 hours.

After the reaction, it was thoroughly washed with acetone and dried under reduced pressure until it reached a constant weight.

The grafting rate determined from the weight difference before and after the reaction was 5.8%.

1001 with a cooling tube attached to the film obtained as above.
The mixture was placed in an rLl flask, and 50w1l of a concentrated hydrochloric acid-methanol solution having a mixing ratio of 1:4 by volume was added thereto, and the mixture was heated on a water bath for 30 minutes.

The grafting ratios of p-acetoxystyrene and divinylbenzene calculated from the difference in weight of the film before and after the hydrolysis treatment were 4.6% and 1.2%, respectively.

Example 3 Graft polymerization was carried out in the same manner as in Example 1 except that 3,4-diacetoxystyrene was used instead of p-acetoxystyrene.

The graft ratio calculated from the weight increase of the obtained graft film was 8.0%.

Example 4 Graft polymerization was carried out in the same manner as in Example 2 except that 3,4-diacetoxystyrene was used instead of p-acetoxystyrene.

The total grafting rate calculated from the weight increase of the obtained graft film was 6.8%, and as a result of further hydrolysis treatment of this graft film, 3,4-diacetoxy, which was calculated from the weight difference between the graft film before and after treatment, was 6.8%. The grafting rate of styrene and divinylbenzene is 5.3% each.
, 1.5%.

Example 5 Polyethylene terephthalate fibers were put into one leg (the thinner side) of a glass H-shaped ampoule (10 mm in diameter, 0.5 mm thick on one leg, and 1 ridge on the other legs), and the other leg was filled with polyethylene terephthalate fiber. A solution of 60% by weight of p-acetoxystyrene and 40% by weight of methanol was added to the container, and after sufficient deaeration by the freeze-thaw method under vacuum, the solution was melt-sealed.

The monomer solution part was frozen, thoroughly covered with a lead plate, and the entire H-type cell was cooled to -30°C. Using an electron accelerator, an electron beam was applied at an acceleration voltage of 2 MeV and an acceleration current of 1 mA for 20 minutes.
Polyethylene terephthalate fibers were irradiated in a Mrad vacuum.

After irradiation, the monomer solution was transferred to the fiber side and reacted at 40° C. for 24 hours.

After the reaction, the package was opened and the fibers were taken out, thoroughly washed with acetone, and dried under reduced pressure until a constant weight was obtained.

The grafting rate calculated from the weight difference before and after the reaction was 12.8%.
Met.

This material did not change in weight even after repeated acetone extraction.

Example 6 Graft polymerization was carried out in the same manner as in Example 5 except that a 60 μm thick polyethylene terephthalate film was used as the backbone polymer.

The grafting rate calculated from the weight increase of the obtained film was 15.1%.

Example 7 Graft polymerization was carried out in the same manner as in Example 5 except that 3,4-diacetoxystyrene was used instead of p-acetoxystyrene.

The grafting ratio calculated from the weight increase of the obtained fiber was 13
．． It was 6%.

Example 8 Graft polymerization was carried out in the same manner as in Example 5 except that a solution consisting of 70% by weight of p-hydroxystyrene and 30% by weight of benzene was used as the monomer solution.

The grafting ratio calculated from the weight increase of the obtained fiber was 2.8.
%Met.

Example 9 As a monomer solution for graft polymerization, 45% by weight of p-7 setoxystyrene and divinylbenzene (purity 55%) were used.
Graft polymerization was carried out in the same manner as in Example 5, except that a solution consisting of 5% by weight (containing 45% ethylstyrene) and 50% by weight methanol was used.

The overall grafting rate was 73%. As a result of hydrolyzing this fiber, the grafting ratios of p-acetoxystyrene and divinylbenzene determined from the weight difference between the grafted fibers before and after the treatment were 5.9% and 1.4%, respectively.

Example 10 A polyethylene terephthalate film was placed in a 30 rnl glass ampoule, a solution of 40% by weight p-hydroxystyrene and 60% by weight toluene was placed thereon, and after repeated deaeration by freeze deaeration method, it was melt-sealed. did.

This material was exposed to cobalt-60 gamma rays at a dose rate of 5X1 at room temperature.
Irradiation was performed for 16 hours at 0.05 rad/hr.

After irradiation, the film was opened and taken out, thoroughly washed with acetone to completely remove by-product p-hydroxystyrene homopolymer, and then dried under reduced pressure until it reached a constant weight.

The grafting rate calculated from the weight difference before and after the reaction was 4.5%.

Claims (1)

[Claims] 1. Graft polymerizing a monomer or a monomer mixture containing hydroxystyrenes and/or acyloxystyrenes represented by the general formula % to a polyester polymer using ionizing radiation. A method for producing a graft copolymer, characterized by: 2. The method according to claim 1, characterized in that a monomer mixture containing hydroxystyrenes and/or acyloxystyrenes and a polyene compound as main components is used.