JPH01101351A - Vinyl chloride-based electrically conductive resin composition - Google Patents

Abstract

PURPOSE:To obtain the title inexpensive composition outstanding in antistaticity and heat resistance, by incorporating a metal salt in a vinyl chloride copolymer containing, as the copolymer components, each specific monomer unit, having both electrical conductivity and heat resistance. CONSTITUTION:The objective composition can be obtained by incorporating (A) a copolymer with an average polymerization degree of 200-1,500, constituted of A1: 50-90wt.% of vinyl chloride unit, A2: 4-25wt.% of (meth)acrylic acid polyalkylene oxide ester unit of formula I (R1 is H or methyl; R2 is polyoxyalkylene with a polymerization degree of 2-23; X is H or 1-6C aliphatic or aromatic hydrocarbon group) and A3: 6-25wt.% of N-substituted maleimide unit of formula II [R2 is 1-30C-(substituted)aliphatic hydrocarbon group or alicyclic hydrocarbon group, etc.] with (B) 0.1-10wt.% of a metal salt such as thiocyanate, phosphate or sulfate (pref. alkali metal salt).

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a vinyl chloride conductive resin composition having excellent antistatic properties and heat resistance.

(Prior Art) Vinyl chloride resins are widely used in various molded products, sheets, and films because they are inexpensive, have good moldability, and have excellent properties. However, molded objects made of vinyl chloride resin are easily charged with electricity, which causes various problems. In order to prevent such charging, attempts have been made to impart electrical conductivity to vinyl chloride resins.

Examples of conductive vinyl chloride resins include resin compositions blended with surfactants, carbon black, metal powder, conductive fibers, etc., and resin compositions coated with surfactants on the surface. However, surfactants blended or applied tend to bleed from the composition or fall off the surface of the composition, so the antistatic effect is not maintained. Blends of carbon black, metal powder, conductive fibers, etc. maintain the antistatic effect, but in order to obtain the desired conductivity, it is necessary to add a large amount of these conductive substances. Therefore, it is expensive. There are also vinyl chloride resin compositions with noble metals or metal oxides attached to the surface by vapor deposition, sputtering, or the like. Although such compositions have excellent antistatic effects, they are expensive and have low productivity.

To solve these drawbacks, carbon black,
There is a vinyl chloride resin composition in which a conductive paint in which a conductive substance such as metal powder is dispersed in a resin solution is applied to the surface. Although this composition is inexpensive and exhibits an excellent antistatic effect, since the conductive substance is foreign to the resin, it is still prone to bleeding and falling off.

In order to prevent bleeding and falling off, a resin composition made of a vinyl chloride copolymer containing a monomer such as an acrylic acid ester unit as a copolymerization component has been proposed. However, although such resin compositions made of vinyl chloride copolymers have excellent antistatic properties, they lack heat resistance and cannot be used at high temperatures.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, and its purpose is to provide a vinyl chloride-based conductive resin that is inexpensive and has excellent antistatic properties and heat resistance. An object of the present invention is to provide a composition.

(Means for Solving the Problems) 1 The present invention includes a specific monomer unit having electrical conductivity and heat resistance as a copolymerization component in the skeleton of a vinyl chloride polymer, and further a complex with this monomer unit. This was completed based on the inventor's knowledge that by introducing a metal salt that is thought to form, antistatic properties and heat resistance can be significantly improved without bleeding or falling off.

The vinyl chloride-based conductive resin composition of the present invention comprises a vinyl chloride unit, a (meth)acrylic acid polyalkylene oxide ester unit represented by the following formula (I), and a (meth)acrylic acid polyalkylene oxide ester unit represented by the following formula (U
) The above object is achieved by incorporating a metal salt into a vinyl chloride copolymer having an N-substituted maleic acid imide unit represented by the following formula.

2 (I) R.

(In the formula, R3 is a hydrogen atom or a methyl group, R2 is a polyoxyalkylene group with a degree of polymerization of 2 to 23, X is a hydrogen atom,
Or it is an aliphatic or aromatic hydrocarbon group having 1 to 6 carbon atoms. ) Formula (I → -CH-CH+ (wherein, R1 is an unsubstituted or substituted aliphatic hydrocarbon group having 1 to 30 carbon atoms, a cyclic aliphatic hydrocarbon group, or an aromatic hydrocarbon group). ) In the present invention, vinyl chloride units are generally contained in the copolymer in an amount of 50 to 90% by weight,
It is preferably contained as a copolymerization component in a range of 55 to 80% by weight.

If it is less than 50% by weight, the properties of the vinyl chloride copolymer will deteriorate. If it exceeds 90% by weight, the desired antistatic properties cannot be obtained.

In addition, the (meth)acrylic acid polyalkylene oxide ester unit is generally contained in the copolymer in an amount of 4 to 25% by weight,
Preferably, it is contained as a copolymerization component in a range of 8 to 20% by weight. If it is less than 4% by weight, it is difficult to obtain the desired antistatic properties.

When it exceeds 25% by weight, heat resistance deteriorates.

As the (meth)acrylic acid polyalkylene oxide ester, for example, polypropylene glycol methacrylate
At least one of the following: is used.

The N-substituted maleic acid imide unit is generally contained in the copolymer in an amount of 6 to 25% by weight, preferably 12 to 25% by weight as a copolymer component. If it is less than 6% by weight, heat resistance will deteriorate.

If it exceeds 25% by weight, it is difficult to obtain the desired antistatic properties.

Examples of the N-substituted maleimide include N-methylmaleimide, N-ethylmaleimide, N-n-propylmaleimide, N-isopropylmaleimide, N-n-butylmaleimide, N-t-1butylmaleimide, N-hexylmaleimide. , N-cyclohexylmaleimide, N-phenylmaleimide, N-di(p,m,o)-hydroxyphenylmaleimide, N-(p,m,o)-methoxyphenylmaleimide, N-(p,m, o)-Chlorophenylmaleimide, N-(p,m.

O)-carboxyphenylmaleimide, N-(p, m,
o)-nitrophenylmaleimide, N-laurylmaleimide, N-bicyclo-(2゜2, ■)-hebutyl-2-
At least one of methylmaleimide, N-9, l0-ethano9.10-dihydroanthracenemaleimide, N-triphenylmethylbenzylmaleimide, etc. is used.

The average degree of polymerization of the above copolymer is in the range of 200 to 1,500, preferably 600 to 1,200. If it is less than 200, the strength will be low, and if it is more than 1,500, moldability and solubility in solvents will be poor.

The vinyl chloride copolymer having vinyl chloride units, (meth)acrylic acid polyalkylene oxide ester units, and N-substituted maleic acid imide units contains a metal salt and is made into a conductive resin composition. . The introduction of this metal salt improves the antistatic properties of the vinyl chloride copolymer.

The amount of this metal salt in the conductive resin composition is generally 0.1 to 1
It is contained in an amount of 0% by weight, preferably in a range of 1 to 7% by weight. If it is less than 0.1% by weight, it is difficult to obtain the desired antistatic properties. If it exceeds 7% by weight, it will bleed and the transparency will deteriorate.

As the above-mentioned metal salt, at least one of thiocyanate, phosphate, sulfate, halogen oxyacid, perhalogen oxyacid, tetrahalogen perborate, polyhalogenated organic strong acid salt, etc. is used. In particular, alkali metal salts such as lithium salts, sodium salts, and potassium salts of the above compounds are preferred. Such compounds include, for example, sodium thiocyanate and lithium perchlorate.

In order to obtain a resin composition by incorporating the above-mentioned metal salt into the above-mentioned vinyl chloride-based copolymer, the above-mentioned metal salt is directly added to the above-mentioned copolymer under appropriate conditions, and mixed or kneaded to obtain a resin composition. However, the above copolymer and metal salt may be dissolved in a suitable organic solvent to obtain a solution of the resin composition, or the organic solvent may be removed from the solution of the resin composition to obtain the resin composition. is preferred. The composition may be in any form such as powder, granules, plates, tubes, sheets, films, various containers, and paint-solutions.

Note that the vinyl chloride copolymer used in the vinyl chloride conductive resin composition of the present invention may contain other monomer units copolymerizable with vinyl chloride to the extent that the antistatic properties are not impaired. It may also be included as Examples of such monomers include olefins such as ethylene and propylene, vinyl esters such as vinyl acetate and vinyl propionate, methyl (meth)acrylate, and ethyl (
meth)acrylate, butyl(meth)acrylate, 2
- Non-functional (meth)acrylates such as ethylhexyl (meth)acrylate and lauryl (meth)acrylate, and vinylidene chloride. Such monomer units are generally included to improve the Tg, viscosity, and solubility of the copolymer.

Any known polymerization method can be used to polymerize the above-mentioned copolymer, such as emulsion polymerization method, suspension polymerization method,
There are solution polymerization method and precipitation polymerization method. As a medium for precipitation polymerization, lower alcohols, particularly methanol, are preferred because of their low cost. In the precipitation polymerization method, since the copolymer is obtained as a fine powder, it is easy to mold it. The polymerization temperature is generally in the range of 35 to 70°C.

The vinyl chloride copolymer used in the vinyl chloride conductive resin composition of the present invention has good solubility in organic solvents. Examples of soluble solvents include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, esters such as ethyl acetate and butyl acetate, chlorinated solvents such as ethylene dichloride and chloromethane, tetrahydrofuran, dimethylformamide, There are polar solvents such as dimethyl sulfoxide.

(Function) The conductive resin composition of the present invention has a specific (meth)acrylic acid polyalkylene oxide ester unit as a copolymerization component of vinyl chloride, and this copolymerization component allows metal salts to be added to the resin composition. A path through which ions can move well is formed continuously, thereby exhibiting good conductivity.

In addition, as a copolymerization component of vinyl chloride, the above specific (
Introducing meth)acrylic acid polyalkylene oxide ester units generally deteriorates the heat resistance of the composition. However, the composition of the present invention further has a specific N-substituted maleic acid imide unit as a copolymer component, and this copolymer component improves the heat resistance of the composition.

Furthermore, the metal salt contained in the copolymer is thought to form a complex with the above-mentioned copolymerization component, thereby preventing bleeding or deterioration of transparency.

(Example) Examples and comparative examples of the present invention are shown below.

Example l.

In a stainless steel autoclave with an internal volume of 20J2 and equipped with a stirrer, 6 kg of methanol and α as a polymerization initiator were placed.
-cumyl peroxyneodecanoate (percumyl ND
, manufactured by Nihon Yushi Co., Ltd.) was charged. After the autoclave was evacuated for 5 minutes using an aspirator, 3.1 kg of vinyl chloride salt and 200 g of N-cyclohexylmaleimide (N-CHMI, manufactured by Nippon Shokubai Kagaku Co., Ltd.) as a formula (II) monomer were added.

31 A stainless steel container (addition container) that can be hung is evacuated, and polyethylene glycol polytetramethylene glycol monomethacrylate (Blenmar 55 PET-800 manufactured by NOF Corporation) 300
After suctioning 1 kg of methanol and 1 kg of methanol, 1.50 kg of vinyl chloride monomer was introduced under pressure. The addition container was shaken to mix the contents and dissolve in methanol, then hung on a spring balance, and a flexible tube was attached to the valve at the bottom of the container, which was connected to the addition nozzle of the polymerization reactor. .

The autoclave's stirrer was rotated at 25 rpm, and hot water was passed through the jacket to raise the temperature to 43°C.

The polymerization reaction started when the temperature reached 43°C.

At this point, the valve on the addition vessel was opened and 47 g of the monomer solution in methanol was added. Thereafter, as the polymerization reaction progressed, the monomer solution was repeatedly added every 5 minutes in 14 times of 63 g, 13 times of 59 g, and 22 times of 53 g. Five minutes after the addition was completed, the autoclave was cooled to 25°C to stop the polymerization reaction.

After the polymerization reaction was completed, unreacted vinyl chloride monomer was released into the atmosphere. Furthermore, nitrogen gas was passed into the autoclave to completely remove the vinyl chloride hetamine, and then the methanol slurry of the copolymer was taken out and filtered. When the filtrate was vacuum-dried at 50"C for 24 hours, 1.40 kg of a white, powdery copolymer was obtained. The copolymer contained 69% by weight of vinyl chloride units and polyethylene glycol polytetramethylene. The copolymer contained 13% by weight of glycol monomethacrylate units and 18% by weight of N-cyclohexylmaleimide units.The average degree of polymerization of the copolymer was 7.
It was 60.

This copolymer was dissolved in a mixed solvent of methyl ethyl ketone/toluene/cyclohexanone (weight ratio 1/1/4),
The solution had a concentration of 18% by weight.

Furthermore, 5.0 kg of lithium perchlorate was added as a metal salt to this copolymer to obtain a solution of a conductive resin composition. This solution was poured onto a glass plate, dried at room temperature for about 24 hours, and then dried under reduced pressure at 50°C for about 48 hours.
A casting film with a thickness of 0.00 μm was produced.

This film's surface resistivity, transparency, bleedability,
And the heat resistance of the copolymer was measured as follows.

These measurement results are shown on the first surface layer.

(I) Surface resistivity The above casting film was heated at 20°C, 60% R) I
After leaving it for 24 hours, use a surface high resistance needle (Hiresta M
The surface specific resistance value was measured using CP-TESTER (manufactured by Mitsubishi Yuka Co., Ltd.).

(2) Transparency The above casting film was visually evaluated as having good or poor transparency.

(3) Bleeding property If the above casting film is left at room temperature and cloudiness or precipitates are observed on the film surface, it is considered defective.
A case in which it was not observed at all was considered good.

(4) Heat resistance To 100 parts by weight of the above copolymer, 2 parts by weight of octyltin mercapto as a stabilizer, 13i parts of octyltin malate polymer, and 0.3 parts of fatty acid ester as a lubricant.
parts by weight were added and kneaded for 4 minutes on a mixing roll with a surface temperature of 180°C to obtain a material sheet. After preheating this material sheet to 180"C for 4 minutes, the surface pressure was 75.
A test piece was prepared by pressing for 4 minutes. The flexibility temperature of this test piece is JIS-
Measured according to 6745.

Example 2 The same method as in Example 1 was carried out except that 150 g of polyethylene glycol polymethylene glycol monomethacrylate and 300 g of N-cyclohexylmaleimide were used.

Example 3 The same method as in Example 1 was carried out except that lithium perchlorate was changed to 3.0% by weight.

Comparative Example 1 The same method as in Example 1 was carried out except that polyethylene glycol polytetramethylene glycol monomethacrylate and N-cyclohexylmaleimide were not added.

Comparative Example 2゜Example 1 except that lithium perchlorate was not added
It was done in the same way.

Comparative Example 3 The same method as in Example 1 was carried out except that 350 g of polyethylene glycol polytetramethylene glycol monomethacrylate was used and N-cyclohexylmaleimide was not added.

Comparative Example 4 The same method as in Example 1 was carried out except that 350 g of N-cyclohexylmaleimide was used and polyethylene glycol polytetramethylene glycol monomethacrylate was not added.

(The following is a blank space) (Effects of the invention) The vinyl chloride conductive resin composition of the present invention has the structure as described above, and therefore has excellent conductivity, low cost, and excellent antistatic properties and heat resistance. .

Moreover, antistatic properties are maintained over a long period of time.

Moreover, it has good solubility, transparency, and bleedability. Therefore, the resin composition of the present invention can be effectively used in conductive sheets, conductive paints, conductive treatment materials, antistatic materials, and the like.

Claims (1)

[Claims] 1. Vinyl chloride unit and (
A vinyl chloride-based conductive resin containing a metal salt in a vinyl chloride-based copolymer having a meth)acrylic acid polyalkylene oxide ester unit and an N-substituted maleic acid imide unit represented by the following formula (II). Composition. Formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1 is a hydrogen atom or a methyl group, R_2 is a polyoxyalkylene group with a degree of polymerization of 2 to 23, and X is a hydrogen atom or a (1 to 6 aliphatic or aromatic hydrocarbon groups.) Formula (II) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (In the formula, R_3 is an unsubstituted or substituted aliphatic group having 1 to 30 carbon atoms. hydrocarbon group or cycloaliphatic hydrocarbon group,
or an aromatic hydrocarbon group. 2. The vinyl chloride conductive resin composition according to claim 1, wherein the vinyl chloride unit is contained in the copolymer in an amount of 50 to 90% by weight. 3. The vinyl chloride conductive resin composition according to claim 1, wherein the (meth)acrylic acid polyalkylene oxide ester unit is contained in the copolymer in an amount of 4 to 25% by weight. . 4. The vinyl chloride conductive resin composition according to claim 1, wherein the N-substituted maleic acid imide unit is contained in the copolymer in an amount of 6 to 25% by weight. 5. The vinyl chloride conductive resin composition according to claim 1, wherein the copolymer has an average degree of polymerization in the range of 200 to 1,500. 6. The vinyl chloride conductive resin composition according to claim 1, wherein the metal salt is an alkali metal salt. 7. The vinyl chloride conductive resin composition according to claim 1, wherein the metal salt is contained in a range of 0.1 to 10% by weight. 8. A patent in which the metal salt is at least one of thiocyanates, phosphates, sulfates, halogen oxyacids, perhalogen oxyacids, tetrahalogenated borates, and polyhalogenated organic strong acid salts The vinyl chloride conductive resin composition according to claim 1.