JPS5850607B2 - Method for producing graft copolymer - Google Patents

Description

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

One purpose of the present invention is to provide a method for producing a new graft copolymer having excellent properties, and another purpose is to improve the adhesiveness, dyeability, water absorption, gas permeability, and The objective is to improve various properties such as oxidation resistance, flame retardance, and reactivity with other compounds, and to use it as ion exchange fibers, ion exchange membranes, reverse osmosis membranes, pressure dialysis membranes, etc.

As a result of various studies for the above purpose, the present inventors have discovered that acyloxystyrenes and/or hydroxystyrenes can be graft-polymerized onto polyamide-based 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 polyamide-based polymers in a similar manner.

The polyamide 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 polyamide polymers. It is a completely new substance with improved reactivity and has many useful uses, such as as a raw material for reactive polymers.

In addition, in the polyamide 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 crosslinked network structure, so that the polyene compound is not grafted. It has superior properties such as chemical resistance, heat resistance and flame retardancy compared to non-polymerized products.

Therefore, the gist of the present invention is to add a monomer mainly composed of acyloxystyrenes and/or hydroxystyrenes or a monomer mixture mainly composed of acyloxystyrenes and/or hydroxystyrenes and a polyene compound to a polyamide polymer. The present invention relates to a method for producing a graft copolymer, characterized in that graft or cograft polymerization is carried out using radiation.

Examples of the polyamide polymer used in the present invention include aliphatic polymers such as polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 6-6), and polyhexamethylene sebamide (nylon 6-10). polyamide,
Aromatic polyamides such as polyethylene terephthalamide, alicyclic polyamides such as POIJ1.4-cyclohexaneadipamide, etc. 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 gelast 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, inoprene,
In addition to phtadiene, cyclopentashne, ethylidene norbornene, 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.

Further, divinylbenzene that 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 used as is for the reaction.

In the present invention, when a monomer mixture mainly composed of acyloxystyrenes and/or hydroxystyrenes and a polyene compound is co-grafted onto a polyamide 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 arbitrarily selected, and the physical properties of the graft copolymer obtained will change depending on the mixing ratio, so the desired graft copolymer The ratio should be selected depending on the physical properties of the acyloxystyrenes and/or hydroxystyrenes and the polyene compound, but a range of 200/1 to 1/1 is usually appropriate, and 50/l to 2/1. A range of 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. An organic solvent that uniformly dissolves the compound or both the polyene compound and the polyene compound is used.

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 butyl acetate, alcohols such as methanol and ethanol, ethers such as tetrahydrofuran and dioxane, N-N-
Amides such as dimethylformamide and N.N-dimethylacetamide, aromatic solvents such as benzene and toluene, aliphatic or alicyclic hydrocarbons such as n-hebutane and cyclohexane, and mixed solvents thereof are suitable.

When the purpose is to graft to the inside of the polyamide 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
, 1 to 80% by weight, preferably 5 to 50% by weight.

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.

Various types of radiation can be used as the ionizing radiation, such as gamma rays, X-rays, electron beams, alpha rays, or mixed radiation of these.

The intensity of the ionizing radiation used, i.e. the dose rate, is 10”
~1011 rad/hour is suitable.

For gamma radiation, dose rates of 10" to 106 rand per hour are usually advantageous, while for electron beams dose rates as high as 109 to 1011 rand per 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 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 irradiation is preferably room temperature or lower.

In carrying out the present invention, when using the pre-irradiation method, the polyamide polymer is irradiated with ionizing radiation in a vacuum, nitrogen stream, or air to generate trapped radicals or polymer peroxides in the polyamide polymer. Then, the polyamide-based 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-generating sites of the polyamide-based 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 polyamide polymer is immersed in an organic solvent solution containing acyloxystyrenes and/or hydroxystyrenes, or these and a polyene compound, and then ionizing radiation is irradiated to the polyamide polymer. Monomers are immediately graft-polymerized onto the radicals generated above.

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 ground ratio of the resulting graft copolymer is not particularly limited, but from the viewpoint of modifying the polyamide 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.

Namely. 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.

Hydrolysis temperature is 50-1o. °C is appropriate.

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 present invention has a side chain mainly composed 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 It is possible to obtain a novel graft copolymer whose main chain is a polyamide-based polymer that has been crosslinked and networked.

This graft copolymer improves or newly develops the disadvantages of polyamide polymers such as adhesion, dyeability, water absorption, gas permeability, oxidation resistance, flame retardancy, and reactivity with other compounds. Graft copolymers with hydroxystyrene groups in their side chains have excellent properties and are used in many applications such as raw materials for reactive polymers, ion exchange fibers, ion exchange membranes, reverse osmosis membranes, and pressure dialysis membranes. It is a useful new substance with

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

Example I 70T of a solution of 50% by weight p-acetoxystyrene and 50% by weight methanol was placed in one leg of a type H glass ampule.
fLl was added and sufficiently degassed using the freeze-thaw method in vacuo.

A nylon-6 film (thickness 200μ,
(weight 2.080P) was irradiated with a 10M electron beam at room temperature in a nitrogen stream.
rad (acceleration voltage 2.0Mev, acceleration current 1.0mA
), the irradiated material was placed, and the vacuum was sufficiently evacuated.

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 ratio calculated from the weight difference before and after the reaction was 110.1
%Met.

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

The infrared absorption spectrum of this film includes nylon-6.
In addition to the unique absorption, 1770cIrL-11200cf
Ester-specific absorption near rL-1, 1615crIL
It is clear that p-acetoxystyrene is graft-polymerized to nylon-6 since aromatic absorption is observed near -11515crfL'.

1001 with a cooling tube attached to the film obtained as above.
50 TL of a concentrated hydrochloric acid-methanol solution having a mixing ratio of 1=4 in terms of volume was added to the flask, and the mixture was heated on a water bath for 30 minutes.

When the obtained film was examined by infrared absorption spectrum, the ester groups were completely hydrolyzed and new absorption based on phenolic hydroxyl groups was observed.

Example 2 A solution consisting of 45% by weight of p-acetoxystyrene, 5% by weight of divinylbenzene (purity 55%, containing 45% ethylstyrene), and 50% by weight of methanol was used as a monomer solution for graft polymerization on a nylon-6 film. Graft polymerization was carried out in exactly the same manner as in Example 1 except for using the following.

The grafting rate was 58.6.

This film was prepared in Example 1 (the grafting rates of p-acetoxystyrene and divinylbenzene calculated from the difference in weight of the film immediately after hydrolysis using the same treatment were 41.1% and 17.5%, respectively). Met.

Example 3 Graft polymerization was carried out in the same manner as in Example 1, except that a nylon 6-6 film with a thickness of 200 μm was used as the backbone polymer.

The grafting rate was 102.3%.

Example 4 A nylon 6-6 film with a thickness of 200μ was used as the backbone polymer, and 45% by weight of p-acetoxystyrene and divinylbenzene (purity 55%, containing 45% ethylstyrene) 5 were used as the monomer solution for graft polymerization. Graft polymerization was carried out in the same manner as in Example 1, except that a solution consisting of 50% by weight and methanol was used.

The grafting rate was 52.4%.

This film was subjected to hydrolysis in exactly the same manner as in Example 1, and the grafting ratios of p-□7 setoxystyrene and divinylbenzene, calculated from the difference in weight between the before and after films, were 37.6% and 14%, respectively. It was 8%.

Example 5 Glass H-shaped ampoule (diameter 107nr/L, thickness of one leg 0.5mrn, other parts 1m7W)
Put cotton-like nylon-6 into one leg (the thinner side), put a solution of 70% by weight p-acetoxystyrene and 30% by weight methanol into the other leg, and freeze and thaw under vacuum. After sufficient deaeration, the container was melt-sealed.

The monomer solution part was frozen, covered sufficiently with a lead plate, and the entire H-type cell cooled to -30°C. Using an electron accelerator, an electron beam of 20M was applied at an acceleration voltage of 2Mev and an acceleration current of 1mA.
The cotton nylon-6 was irradiated in a rad vacuum.

After irradiation, the monomer solution was transferred to the cotton-like nylon-6 side and reacted at room temperature for 24 hours.

After the reaction, the package was opened and the cotton-like nylon-6 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 170%.

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

Example 6 Glass H-shaped ampoule (diameter 107nrIL, wall thickness one FIQ part 0.5mrn, other parts 1mrn)
200μ thick nylon on one leg (thinner side) of
6, and the other leg contains 47.5% by weight of P-acetoxystyrene, divinylbenzene (purity 55%, 4
A solution of 2.5% by weight (containing 5% ethylstyrene) and 50% by weight of methanol was poured into the container, and after sufficient degassing by freeze-thaw method under vacuum, it was melt-sealed.

Freeze the monomer solution, cover it thoroughly with a lead plate, cool the entire H-type cell to -30°C, and use an electron accelerator to generate an electron beam of 7M at an acceleration voltage of 2Mev and an acceleration current of 1mA.
The film was irradiated in a rad vacuum.

After irradiation, the monomer solution was transferred to the film side and allowed to react at room temperature for 24 hours.

After the reaction, the film was opened, 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 92.7%.
Met.

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

This film was hydrolyzed in the same manner as in Example 1, and the grafting rates of P-acetoxystyrene and divinylbenzene calculated from the difference in weight between the before and after films were 73.8% and 18.9%, respectively.

Example 7 A monomer solution for graft polymerization on a nylon-6 film was prepared from 3,4-diacetoxystyrene (wt%), divinylbenzene (purity 55%, containing 45% ethylstyrene) (5 wt%), and methanol (50 wt%). Graft polymerization was carried out in exactly the same manner as in Example 6, except that the solution used was

The grafting rate was 73.4%.

Hydrolysis was carried out in the same manner as in Example 1, and the grafting ratio of 3,4-diacetoxystyrene and divinylbenzene, determined from the difference in weight before and after hydrolysis, was 60.1%, respectively.
Example 8 A nylon-6 film was placed in a 30TfLl glass ampule, and 40% by weight of p-hydroxystyrene was placed on top of it.
A solution containing 60% by weight of toluene was added thereto, and after sufficient deaeration was repeated by freeze deaeration, it was melt-sealed.

This product was heated at room temperature with gamma rays of -60 (Kobal) at a dose rate of 5.
Irradiated at X 105red/hr for 16 hours.

After irradiation, the unsealed film was 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 17.2%.
Met.

The infrared absorption spectrum of this film includes nylon-6.
In addition to the characteristic absorption, there is an OH absorption near 3300crfL-1, an aromatic-specific absorption near 1615CrfL' and 1515CIrL-1, and a C-O absorption near 1250crfL'.
It is clear that p-hydroxystyrene is grafted onto nylon-6.

Claims (1)

[Scope of Claims] 1. A polyamide polymer containing hydroxystyrenes and/or acyloxystyrenes represented by the general formula (at least one -R is a hydrocarbon group and n is 1 or 2) as a main component. 1. A method for producing a graft copolymer, which comprises graft-polymerizing a monomer or a monomer mixture using ionizing radiation. 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.