JPS5932489B2 - Surface modification method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to surface modification of substrates made of natural or synthetic polymers.

Today, natural and synthetic polymers are used in a wide range of fields and have become extremely important base materials. For example, they are used in various forms in a wide range of fields, including textiles and plastics. However, these base materials have various drawbacks, and the current situation is that these materials are used in spite of these drawbacks. In particular, it is a well-known fact to those who handle these base materials that the surfaces of these base materials have extremely difficult defects.
The surface of the base material has many drawbacks, such as poor dyeability in fibers, easy generation of static electricity, poor adhesive performance in plastic films, and poor printing performance.
However, it is thought that these can be improved by modifying the surface of the base material and the functions of the base material can be fully exhibited. Although many surface modification methods have been proposed to date, no satisfactory method has yet been proposed.

The most commonly used modification method at present is a method of coating a substrate with polymers having various properties. However, as mentioned above, the surface of the base material has extremely poor adhesion, and the coating often peels off during use, and Machi-Usumi's coating dissolves and washes away during use, reducing its performance. At the same time, it is necessary to apply the coating extremely thinly to the extent that the function of the base material is not deteriorated, and this technical difficulty is also an important problem. Radiation grafting is a method that solves these various drawbacks. This is a surface modification method in which radicals are generated in the base material by irradiating the base material with radiation, and various monomers are graft-polymerized using the radicals as a starting point. Since the modified layer formed by this method is grafted, it is less susceptible to deterioration in performance due to peeling or dissolution, and since the grafted polymer layer is thin, there is no deterioration in base material functionality, resulting in excellent properties. Although it is said to be a surface modification method, this method has the following fatal disadvantages. Because the energy of the radiation is extremely large, the radiation is injected not only onto the surface of the base material but also into the interior, damaging the base material and impairing its functionality. Another serious problem is that radiation irradiation equipment requires great care in handling and safety. In addition, there is a method in which vinyl chloride powder is treated with high-frequency high-voltage discharge under a pressure of 0.1 Hg, and then acrylonitrile is introduced and graft polymerized onto the powder surface.
A method has been proposed in which acrylic acid or the like is graft-polymerized after unsteady spark discharge treatment at mmHg or higher and substantially atmospheric pressure.

All of these methods simply provide a graft polymer layer of a single monomer on the surface of a substrate such as powder or plastic, and such a polymer layer alone does not provide the necessary and effective surface for various uses. It is difficult to carry out modification, and in such cases, monomers were synthesized according to the purpose, but this synthesis itself was extremely difficult, and the synthesized product had to be further purified for use in grafting. This is also a problem from the point of view of increasing costs. What is more decisive, as will be described later, is that many of the monomers have poor ability to perform graft polymerization by discharge, making it impossible to apply the conventionally known discharge graft polymerization method. The present invention completely eliminates the above-mentioned conventional drawbacks, allows surface properties suitable for various uses to be easily imparted to base materials, and greatly improves the performance and durability.

In order to achieve this object, the present invention has the following configuration.

That is, the surface of the base material made of natural polymers, synthetic polymers, or mixtures thereof is heated to a temperature of 0.2TrLmHg or more 20m7
! After processing with high voltage discharge under gas pressure below LHg,
forming a graft polymerized layer of the monomer on the surface of the substrate by exposing it to one or more monomers selected from the group of acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester; Next, a chemical treatment is performed using a compound that can chemically bond with the graft polymer layer. In the present invention, natural polymers include, for example, cotton, linen, silk, cotton, etc., and synthetic polymers include, for example, polyester, polyamide, polyacrylonitrile, polyethylene, polypropylene, polystyrene, polycarbonate, and polyvinyl chloride. , polyvinylidene chloride, cellulose acetate, cellophane and other fibers and resins, as well as ABSl acrylic, methacrylic,
Plastic resins such as phenol, elia, melamine, epoxy and the like may be mentioned.

Such substances may be used alone or in a mixture, and may be in any shape such as fibrous, plate, sheet, cylindrical, block, etc., but the present invention It is particularly suitable for films and textiles.
The high voltage discharge of the present invention refers to air, nitrogen, nitrogen dioxide, hydrogen, argon, helium, chlorine fluoride, carbon chloride, carbon fluoride under a pressure higher than 0.2 mmHg, preferably 0.3 mmHg or more and 20 mmHg or less. Alternatively, the treatment is performed by a discharge initiated and sustained by a high voltage in an atmosphere such as a mixed gas of these.

If the pressure is less than 0.2 mmHg, the base material may be crosslinked or yellowed, making graft polymerization impossible, and the mechanical properties of the base material may deteriorate. On the other hand, if it exceeds 20 mmHg, the activation efficiency of the base material by discharge becomes poor and graft polymerization hardly occurs. The surface of the base material subjected to such discharge treatment is activated, and then one type Y of the monomer selected from the group of acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester is exposed to two or more types. A graft polymerization layer of the monomer is formed on the surface of the base material.

It is known that various monomers are graft-polymerized in normal radiation graft polymerization and ultraviolet graft polymerization, but in this method, acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, 2-vinylpyridine, styrene, etc. , acrylonitrile, and acrylamide could not be clearly verified to be graft polymerized. However, 2-vinylpyridine, styrene, acrylonitrile, and acrylamide monomers do not undergo graft polymerization unless they are heated when exposed to the substrate, and there is a problem that a large amount of homopolymerization is generated in this case, so they cannot be used. It was impossible. Specific examples of acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester used in the present invention include methacrylic acid, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, and 2-dimethylaminoethyl methacrylate. , 2-diethylaminoethyl methacrylate, 2-dimethylaminoethyl acrylate, 2-
Diethylaminoethyl arylate, glycidyl methacrylate, glycidyl acrylate, etc. can be mentioned, among which acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, 2-diethylaminoethyl methacrylate and glycidyl methacrylate are particularly excellent.

In the present invention, one or more types of such monomers can be used to graft-polymerize the base material, and generally, using two or more types can impart a plurality of properties than when only one type is used.
The monomer may be exposed to the substrate in either liquid or gaseous state. The thickness of the graft polymer layer made of the above monomer of the present invention is about 1 μm or less (approximately 0.2 to 1.0 μm).
around m). The substrate having the graft polymerization layer of the present invention is then treated with a surface-modifying compound capable of chemically bonding with the graft polymerization layer.

Here, the surface-modifying compound may be any compound that chemically bonds with the graft polymer and exhibits properties such as adhesiveness, antistatic property, stain resistance, and hygroscopicity; Such a compound is selected depending on the type of monomer forming the graft polymerization layer and the surface characteristics to be introduced, and is not particularly limited. For example, introducing a sulfonic acid group into a graft polymerized layer of graft polymerized polyacrylic acid,
For the purpose of imparting antistatic properties, sodium hydroxyethylsulfonate or sodium hydroxypropylsulfonate may be used to carry out an esterification reaction. In addition, when introducing a glycidyl group, glycidyl methacrylate may be directly graft-polymerized, but the graft-polymerized layer of polyacrylic acid graft-polymerized by the discharge grafting method is first converted into a sodium salt with the polyacrylic acid using NaOH. Alternatively, an esterification reaction may be carried out using epichlorohydrin. Depending on the purpose, the reaction in the present invention may be completely terminated and the desired functional group may be introduced into the entire graft layer, or the reaction may not be completely terminated and the functional group may be partially introduced into the graft layer. Good too. When functional groups are partially introduced into the graft layer, it is also possible to synergistically exhibit the desired performance with the remaining functional groups possessed by the graft layer itself. For example, in the above-mentioned introduction of glycidyl groups, if the polyacrylic acid in the graft layer is partially converted into a sodium salt and then reacted with epichlorohydrin, the graft layer contains carboxyl groups and glycidyl groups and exhibits the properties of both functional groups at the same time. It is possible to do so. Typical examples of reactions applied in the surface modification of the present invention include, in addition to those mentioned above, the following.

(1) The graft-polymerized acrylic acid is reacted with a diazoparaffin such as diazomethane or diazoethane to form a polyacrylic acid ester.

(2) Introducing an amino group by causing an imination reaction between the graft-polymerized acrylic acid and an aziridine compound such as ethyleneimine or 1,2-propyleneimine. (3) Introduction of unsaturated hydrocarbon groups by transesterification of graft-polymerized methyl acrylate and unsaturated alcohol such as allyl alcohol.

(4) After the graft-polymerized acrylic acid is made into a sodium salt, it is reacted with a monohalogenated fatty acid ester such as talol acetate to introduce an alkoxycarbonyl group.

(5) Graft-polymerized acrylic acid and epichlorohydrin are reacted to form a hydroxy group and chlorine guide.

(6) After the graft-polymerized acrylic acid is made into a potassium salt, it is reacted with a 3-halogenated-2-hydroxypropyltrimethylammonium salt to form a hydroxyl group and a potassium salt.
Introduction of grade ammonium bases.

(7) Introducing halogen by transesterifying the graft-polymerized acrylic acid with a halogenated alcohol or halogenated phenol such as dibromopropyl alcohol.

(8) Graft-polymerized acrylic acid is made into a sodium salt and reacted with an aromatic 2-halogenated alkyl such as 2-chloroethyl benzoate to introduce a benzoyloxy group.

(9) After the graft-polymerized acrylic acid is made into a sodium salt, it is reacted with a benzyl halide such as benzyl chloride to introduce a benzyl group.

(Self) After converting the graft-polymerized acrylic acid into a sodium salt, a halogenated alkyl styrene such as parachloromethylstyrene is applied to introduce a vinyl-substituted benzyl group.

(Auto) A hydrazine compound such as hydrazine hydrate is reacted with graft-polymerized methyl acrylate to form a hydrazide compound.

02) Introduction of a quaternary ammonium base by reacting graft-polymerized diethylaminoethyl methacrylate with an alkyl halide or alkyl sulfate such as methyl iodide or ethyl sulfate.

(Auto) Reaction of graft-polymerized glycidyl methacrylate with an amino compound such as diethylamine to introduce hydroxy groups and amino groups. A4) Introduction of a hydroxyl group and a sulfonic acid group by reacting graft-polymerized glycidyl methacrylate with a hydrogen sulfite such as sodium hydrogen sulfite. (15) Reaction of graft-polymerized glycidyl methacrylate with carpoxylic acid such as acetic acid to introduce hydroxy groups and acyloxy groups.

(16) Introduction of phenoxy groups by reacting graft-polymerized glycidyl methacrylate with phenols such as carbolic acid.

07) Introduction of cyano groups by reacting graft-polymerized acrylic acid with a cyano alcohol such as 2-cyanoethyl alcohol.

08) Introduction of hydroxy groups by reacting graft-polymerized atarylic acid with alkylene oxide such as propylene oxide.

As seen in the reaction examples above, the surface-modifying compounds used in the present invention include diazoparaffins, imine compounds, amino compounds, imino compounds, hydrazine compounds, unsaturated alcohols, substituted alcohols, ethylene glycol, and polyethylene glycol. Aliphatic polyhydric hydroxy compounds, alicyclic hydroxy compounds such as cyclohexanol, alkylammonium salts, alkyl sulfates, aliphatic hydroxysulfonates, halogenated glycidyl hydrocarbons represented by benzyl halides, alkylene oxides, epichlorohydrin, Examples include bisulfite, phosphorus compounds, etc., but are not limited thereto, and any compound can be applied to the method of the present invention as long as it can react with the graft polymerization layer and impart the desired performance.

Next, the surface properties and surface modification compounds to be modified based on the above reaction examples will be specifically explained below.

Reaction Example 1 can improve adhesion and heat sealing properties with various resins, and the applicable compounds are diazomethane, diazoethane, and diazopropane.

Adhesion and dyeability can be improved by reaction example 2, and the applicable compounds are ethyleneimine, 1,2-propyleneimine, n-butylaziridine, 2,2-dimethylaziridine, and 2-ethylaziridine. be.

Adhesion can be improved by Reaction Example 3, and the compound used is allyl alcohol.

In Reaction Example 4, the adhesion properties can be improved, and the applicable compounds are sodium hydroxide and monochloroacetate, monochloropropionate, and monochlorobutyrate. Depending on Reaction Example 5, the adhesion to various resins and glass can be improved, and the compound to be applied is epichlorohydrin. Depending on Reaction Example 6, hydrophilicity, antistatic property, staining property, bactericidal activity and stain removal property can be imparted, and the applicable compounds are potassium hydroxide, 3-chloro-2-hydroxypropyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltrimethylammonium chloride, It is chloro-2-hydroxypropyltriethylammonium chloride.

Flame retardancy can be imparted by Reaction Example 7, and the applicable compounds are 2,3-dibromopropyl alcohol and tripromphenyl. Compounds that can improve adhesion according to Reaction Example 8 are 2-chloroethyl benzoate, 1-chloromethyl benzoate, 2-chloroethyl salicylate, and 1-chloromethyl salicylate.

Adhesion can be improved by Reaction Examples 9 and 10, and the compounds used are benzyl chloride and chloromethylstyrene. Adhesion can be improved by Reaction Example 11, and the compounds used are hydrazine hydrazine and phenylhydrazine.

Hydrophilicity and antistatic properties can be imparted by Reaction Example 12, and the applicable compounds are methyl iodide, ethyl iodide, propyl iodide, methyl bromide, ethyl bromide, propyl bromide, methyl chloride, ethyl chloride, and chloride. These are propyl, methyl sulfate, and ethyl sulfate.

Reaction Example 13 improves adhesion and imparts town dyeing performance against acidic dyeing phases, and the applicable compounds include dinotylamine, diethylamine, dibutylamine, monomethanolamine, monoethanolamine, dimethanolamine,
These are diethanolamine, aminobenzene, phenylethylamine, and 2-(2'-hydroxy-2'-phenylethylamino)ethanol.

Reaction Example 14 can provide improved adhesion, antistatic properties, and dyeability against basic dyeing phases, and the compound to be applied is sodium bisulfite.

Adhesion can be improved by Reaction Example 15, and the compounds used are formic acid, acetic acid, propionic acid, butyric acid, and isobutyric acid. The adhesion properties can be improved according to Reaction Example 16, and the applicable compounds are carbolic acid, salicylic acid, salicyl alcohol, salicyl aldehyde, salicyl aldoxime, aminophenol, and nitrophenol.

According to Reaction Example 17, oil resistance can be improved, and the applicable compounds are cyanomethyl alcohol, 2-cyanoethyl alcohol, 2-cyanopropyl alcohol, and 3-cyanopropyl alcohol.

Reaction Example 18 can improve adhesion with various resins and impart hydrophilicity, antistatic properties, antifogging properties, and town dyeing performance for reactive dyes, and the compounds to be applied are ethylene oxide and propylene oxide.

The compounds applied to the above reaction examples are not limited to the above-mentioned compounds, but may be any compound that reacts with the graft layer and imparts the desired performance. Furthermore, the present invention is not limited to the above reaction example, and the substrate treated by high voltage discharge is treated with one type of monomer selected from the group of acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester. Any material may be used as long as it reacts with the graft polymerized layer formed by exposing the material to a higher temperature than that and imparts the desired performance. In the description of the present invention, the step of exposing to monomer was described in detail only for monomer vapor, but the present invention is not limited to the method of exposing to monomer vapor, and two types of The monomer is applied to the substrate by exposing it to the above mixed monomer solution, for example, a mixed solution of acrylic acid and sodium salt of sulfopropyl methacrylate, a mixed solution of acrinoleic acid and 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, etc. may be graft polymerized.

The method of the present invention will be described in more detail by way of examples. Example 1 Polypropylene film C5 trephan 51)
Activate the surface by exposing it to a high voltage discharge for 30 seconds in mmHg(7)Ar gas.

The surface of the substrate is then heated to 50° C. and exposed to generated acrylic acid vapor for 5 minutes to form a graft polymerized layer of acrylic acid on the surface of the substrate. When the base material thus obtained is immersed in a basic dye (AstrazOnBlueBG),
Instantly, the back is dyed sky blue and 100dyne/0r
It showed an adhesion work to water of IL or higher, and it was possible to identify that a graft polymerized layer of acrylic acid was formed on the surface of the base material. Next, the acrylic acid grafted polypropylene was immersed in a solution having the composition shown in Table 1, and after purging the inside of the reactor with nitrogen gas,
Heat to 75°C and add 1 gaseous propylene oxide.
Blow at a rate of 09/hour. After reacting for about 1 hour, the substrate was thoroughly washed with water to wash away the solvent and catalyst adsorbed on the surface. The thus surface-modified base material was dyed with a basic dye (AstrazOnBlueBG) and an acidic dye (AcidOrange), resulting in sky blue and orange dyeing. The substrate grafted with acrylic acid can only be dyed with basic dyes, and untreated polypropylene film cannot be dyed at all. The surface-modified film was coated with vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, cellulose butyrate acetate, and nitrocellulose as adhesives, and the adhesive strength was examined by zero tape peeling. As a result, as shown in Table 2, the present invention was confirmed. The product was shown to have excellent adhesive ability. Comparative Examples 1 and 2 A polypropylene film was subjected to electrical discharge treatment in the same manner as in Example 1, and then exposed to acrylic acid vapor to attempt graft polymerization of acrylic acid onto the surface of the substrate.

In Example 1, discharge treatment was performed in Ar gas of 1 TfLmHg, whereas in Comparative Example 1, discharge treatment was performed in 0.1 mmHg (7) Ar gas, and in Comparative Example 2, discharge treatment was performed in 100 mmHg (7) Ar gas.

All other conditions were kept the same. Although the polypropylene film of Comparative Example 1 graft-polymerized in this manner had an improved adhesion work to water of 100 dyne/i or more, it was hardly stained with basic dyes. In Comparative Example 2, the adhesion work against water was 96dy.
A slight improvement in ne/CrfL was observed, but as in Comparative Example 1, it was not dyed with basic dyes at all. Each graft-polymerized polypropylene film was reacted with propylene oxide in the same manner as in the example, and its dyeability and adhesion were examined, but both the samples of Comparative Examples 1 and 2 were not dyed, and did not adhere to anything other than nitrocellulose. , these sample surfaces were not modified.

Comparative Examples 3 and 4 A polypropylene film was subjected to electrical discharge treatment in the same manner as in Example 1, and then exposed to a 50% by weight aqueous solution of acrylamide in an attempt to graft-polymerize acrylamide onto the surface of the substrate.

In Comparative Example 3, the acrylamide aqueous solution temperature was set to 2C and in Comparative Example 4, it was 60C, and the discharge treated polypropylene was immersed for 5 minutes. Comparative Example 3 in which these polypropylene films were washed with water and dried after graft polymerization in this manner.
The surface of the sample graft-polymerized at a monomer temperature of 20°C was almost unchanged, and the acid dye (AcldO
range), and it was found that no graft polymerization occurred.

A sticky polymer was stuck to the surface of the sample of Comparative Example 4, and it was difficult to remove it even when washed with water. From this, it was inferred that acrylamide was graft-polymerized on the surface of this sample and acrylamide homopolymer was attached to it, but since a homopolymer is formed, it is inappropriate as a monomer for use in surface modification of the film. It turns out that it is. Example 2 Polyester film (1 Lumira - 1T) 0.6 mm
Discharge treatment was performed for 10 seconds in Hg0N2-02 mixed gas,
After activating the surface, it was heated to 8℃ and the generated 2-
exposure to dimethylaminoethyl methacrylate vapor;
The monomer was graft-polymerized onto the surface of the base material.

The surface-modified base material is treated with acid dye (AcldOrang).
As a result of staining in step e), it was dyed orange, and it was possible to identify that the monomer had been graft polymerized.Then, the surface-modified base material was immersed in a mixed solution of dimethylformamide and methyl iodide for 30 minutes. After being left to stand, it was taken out and thoroughly washed with water.

In order to investigate the antistatic properties of the surface-modified polyester film thus obtained, the attenuation characteristics of accumulated surface charges due to corona discharge were investigated. As shown in Table 3, the polyester film whose surface was modified by the method of the present invention exhibited extremely good antistatic properties. When methyl iodide is used as a reactant, the surface turns yellow, but this can be solved by using methyl chloride.

Furthermore, by subsequently reacting with AgOH, it was possible to impart hydrophilicity as well as antistatic property. Similar experiments were conducted on polyester fibers, and polyester fibers with extremely good antistatic properties were obtained.

Example 3 Polyester fibers were heated for 10 minutes in 1 mmHg (1) N2 gas.
After activating the surface by exposing it to electric discharge for seconds, apply a mixed solution of 2-dimethylaminoethyl methacrylate and acrylic acid (5
A graft layer of the monomer was formed on the surface of the fiber by immersing it in a 50% by weight methyl alcohol solution (0 mol %: 50 mol %).

The fibers were then left in a mixed solution of methyl iodide and methyl alcohol at 40°C for 30 minutes. The treated fibers are extremely hydrophilic and have excellent antistatic properties as shown in Table 4. The evaluation method for anti-static housing was the same as in Example 2. Example 4 A polypropylene film ("Trejuan") was prepared at a temperature of 0.
After the substrate surface was activated by exposing it to a 50W discharge in 6 mmHg (J) Ar gas for 30 seconds, it was heated to 30'C and exposed to the generated methyl acrylate vapor for 2 minutes, and the substrate surface was exposed to the generated methyl acrylate vapor for 2 minutes. The monomers were graft-polymerized.

The surface-modified base material is subjected to dispersion dyeing (DianixRe).
As a result of staining with dF3B-Fs), the monomer was stained pink, and it was possible to identify that the monomer had been graft-polymerized. Then, the surface-modified base material and 2-cyanoethyl alcohol (300y) and para-toluenesulfonic acid (5f1) were heated in a flask under reflux at 65°C for 1 hour.

Methanol by-produced by transesterification is distilled off. After the reaction was completed, the substrate was taken out and thoroughly washed with isopropyl alcohol to wash away adsorbed 2-cyanoethyl alcohol and para-toluenesulfonic acid. As a result of measuring the total reflection infrared absorption spectrum of the polypropylene film surface-modified in this way, a weak absorption spectrum was observed near 2,250 CwL-'' and a strong absorption spectrum near 1.730 cnL-1. It was confirmed that groups and esters were introduced.Example 5 Polyester film ("゜lumira-ichi") was 0.6 m long.
After activating the surface by exposing it to an electrical discharge for 20 seconds in mHg N2 gas, the fabric was treated with 50% glycidyl methacrylate.
A graft polymer layer of glycidyl methacrylate was formed on the surface of the cloth by immersing it in a tetrahydrofuran solution.

Claims (1)

[Claims] 1. The surface of the base material made of natural polymers, synthetic polymers, or mixtures thereof is heated to 0.2 mmHg or more and 20 mmHg.
After being treated with high voltage discharge under the following gas pressure, the substrate surface is exposed to one or more monomers selected from the group of acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester. 1. A surface modification method comprising: forming a graft polymer layer of the monomer, and then chemically treating with a compound capable of chemically bonding with the graft polymer layer.