JPH09241508A - Microwave-weldable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a microwave-weldable resin compsn. which exhibits a high heat exchange rate and provides a high amt. of heat and of which the heat generation can be easily controlled, enabling the prevention of degradation of the resin, by compounding a thermoplastic resin with fine conductive aniline polymer particles and a conductive inorg. powder. SOLUTION: This compsn. comprises 100 pts.wt. thermoplastic resin, 5-100 pts.wt. fine conductive aniline polymer particles, and 3-50 pts.wt. conductive inorg. powder, the content of the polymer particles being higher than that of the inorg. powder. Examples of the resin are a polyolefin resin (e.g. polyethylene or polypropylene), a vinyl chloride resin, and an acrylic resin. Examples of the inorg. powder are barium titanate, titanium oxide, a metal powder such as of copper or zinc, and carbon black.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for microwave fusion, and more specifically, a microwave suitable for use in joining synthetic resin pipes and other adherends having a heat fusion property. The present invention relates to a resin composition for fusing.

[0002]

2. Description of the Related Art Conventionally, a resin fusion method utilizing dielectric heating by microwave has been disclosed in, for example, Japanese Patent Laid-Open No. 62-392.
No. 21 discloses that a fusion material obtained by kneading a polyolefin resin with carbon black is sandwiched between the connection portions of a polyolefin resin molded article as an adherend, and high-frequency power is applied to the fusion material sandwich portion. A method for fusing and connecting polyolefin resin molded products is disclosed, and Japanese Patent Publication No.
No. 11022, a vinyl chloride resin, a polyamide resin, and an ethylene resin having a large dielectric loss value are provided between connecting portions of a thermoplastic resin molded article having a small dielectric loss value, which is an adherend.
A method of fusion-bonding a thermoplastic resin molded product having a small dielectric loss value by heating the above-mentioned heat-generating material by high-frequency dielectric heating or high-frequency induction heating through a heat-generating material made of vinyl acetate copolymer, polyester resin, etc. Is disclosed.

However, the fusing material using the above carbon black has problems that the carbon black itself generates heat at a high temperature, which causes deterioration of the resin and the heat generation temperature is difficult to control. In addition, the thermoplastic resin molded product fusion method with a small dielectric loss value using a resin with a large dielectric loss value has a problem that it takes a long time to increase the temperature.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has a high heat exchange rate, a high amount of heat can be obtained, and heat generation control that can prevent deterioration of a resin is easy. An object is to provide a resin composition for microwave fusion.

[0005]

According to the present invention, 100 parts by weight of a thermoplastic resin and conductive aniline polymer fine particles 5-1 are used.
Microwave, which comprises 00 parts by weight and 3 to 50 parts by weight of the conductive inorganic powder, and the content of the conductive aniline polymer fine particles is higher than the content of the conductive inorganic powder. The gist is a resin composition for fusing.

The above-mentioned thermoplastic resin is not particularly limited as long as it is a thermoplastic resin which can be extrusion-molded or injection-molded, and for example, polyolefins such as polyethylene, polypropylene, polybutene-1, poly-4-methylpentene and the like. Examples of the resin include vinyl resin, vinyl chloride resin, polycarbonate resin, polyester resin, polyamide resin, acrylic resin, polyphenylene sulfide resin (PPS), and perfluoroalkoxy fluororesin (PFA). These may be used alone or in combination of two or more.

The above conductive aniline polymer fine particles are
It is not particularly limited as long as it is conductive, and among them, an aniline-based polymer having a conductivity of 0.1 S / cm or more is preferable. When the conductivity is lower than 0.1 S / cm, heat generation is insufficient and fusion is insufficient, which is not preferable.

The above aniline-based polymer fine particles are, for example,
The aniline derivative monomer and the acid are dissolved in a solvent such as water, and an oxidant is added to this solution, and the mixture is stirred to carry out oxidative polymerization.

Examples of the aniline derivative monomer include aniline, N-methylaniline, N-ethylaniline, o-toluidine, m-toluidine, 2-ethylaniline, 3-ethylaniline, 2,3-dimethylaniline, 2 , 5-dimethylaniline, 2,6-dimethylaniline, 2,6-diethylaniline, 2-methoxyaniline, 3-methoxyaniline, 2,5-dimethoxyaniline, 3,5-dimethoxyaniline, o-phenylenediamine, m -Phenylenediamine, 2-aminobiphenyl, N, N-diphenyl-p-phenylenediamine and the like can be mentioned. The concentration of the aniline derivative monomer in the solvent is preferably 0.1 to 1 mol / l.

Examples of the acid include inorganic protonic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid; inorganic acid esters such as sulfuric acid ester and phosphoric acid ester; organic acids such as p-toluenesulfonic acid and carboxylic acid; polystyrene. Polymeric acids such as sulfonic acid may be mentioned. The concentration of the acid is 0.1 N
1N is preferred.

Examples of the oxidizing agent include persulfate,
Examples thereof include peroxides such as hydrogen peroxide, permanganate, and dichromate; Lewis acids such as lead dioxide, manganese dioxide, and iron chloride. The concentration of the oxidizing agent is preferably 0.1 to 1 mol / l with respect to the solvent.

The above conductive aniline polymer fine particles are
It can be prepared by the above method, but a commercially available product such as "Versicon" manufactured by Allied Signal Co. can also be used.

The conductive inorganic powder is not particularly limited as long as it is a conductive powder that generates heat when irradiated with microwaves. For example, barium titanate, potassium titanate, titanium oxide, sulfuric acid. Aluminum, tin oxide,
Examples thereof include metal powders such as zinc oxide, copper, zinc, and stainless steel, carbon black, and powders in which a tin oxide-based conductive thin film is formed on the surface of barium sulfate.

The above conductive aniline polymer fine particles are
5 to 100 parts by weight are dispersed in 100 parts by weight of the thermoplastic resin. If the amount is less than 5 parts by weight, the calorific value becomes insufficient, and 10
If the amount exceeds 0 parts by weight, the strength of the resin composition for microwave fusion decreases, so the content is limited to the above range.

The conductive aniline polymer fine particles dispersed in the thermoplastic resin have a particle diameter of 0.1 to 0.1.
It is desirable to use those having a particle size in the range of 100 μm. When the particle diameter is less than 0.1 μm, it becomes difficult to disperse the particles in the thermoplastic resin, and excessive kneading causes deterioration of the thermoplastic resin. On the other hand, if the particle diameter exceeds 100 μm, a sufficient amount of heat generated during microwave heating cannot be obtained and the fusion strength is reduced.

The dispersed particle size of the conductive aniline polymer fine particles is not particularly limited as long as it can accurately measure the particle size. For example, RuO _{4 is} previously prepared.
When the resin composition for microwave fusion dyed with is observed by backscattered electrons of a scanning electron microscope, it can be measured relatively easily.

The conductive inorganic powder is dispersed in an amount of 3 to 50 parts by weight in 100 parts by weight of the thermoplastic resin. If it is less than 3 parts by weight, the amount of heat generation becomes insufficient, and if it exceeds 50 parts by weight, not only is it difficult to control heat generation, but also the strength of the resin composition for microwave fusion is lowered, so the amount is limited to the above range.

It is desirable to use the conductive inorganic powder having a particle diameter in the range of 0.01 to 100 μm. If the particle diameter is less than 0.01 μm,
Dispersion in the thermoplastic resin becomes difficult, and excessive kneading causes deterioration of the thermoplastic resin. The particle size is 100μ
When it exceeds m, the strength of the resin composition for microwave fusion is reduced, the heat generation amount at the time of microwave heating is not sufficiently obtained, and the fusion strength is also reduced.

In the resin composition for microwave fusion, the content of the conductive aniline-based polymer fine particles is
It is always higher than the content of the conductive inorganic powder. When the content of the conductive inorganic powder exceeds the content of the conductive aniline polymer fine particles, it becomes difficult to control heat generation of the microwave fusion resin composition.

The method for producing the resin composition for microwave fusion of the present invention is not particularly limited, and examples thereof include a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneading roll, a Brabender plastograph, A kneading device such as a kneader is used alone or in appropriate combination of these devices, and in the thermoplastic resin, the conductive aniline polymer fine particles and the conductive inorganic powder are mixed,
It is manufactured by kneading at the melting temperature of the thermoplastic resin. Furthermore, the resin composition for microwave fusion of the present invention,
If necessary, a dispersant such as a silane compound, an ultraviolet absorber,
Antioxidants, flame retardants, plasticizers, lubricants, antistatic agents, colorants and the like may be added.

Examples of the silane compound include chlorosilanes such as methyltrichlorosilane, methyldichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane and diphenyldichlorosilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, Tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, isobutyltrimethoxysilane,
Examples include alkoxysilanes such as decyltrimethoxysilane, and among them, alkoxysilanes are preferably used.

As the silane compound, for example, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxymethyldimethoxysilane, γ-methacryloxymethyldiethoxysilane, N-β- (aminoethyl) γ-aminopropylmethyl Dimethoxysilane, N-β- (aminoethyl) γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane , N-F Similarly, silane coupling agents such as phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane and the like are preferably used.

Further, as the silane compound, for example,
Amino-modified, epoxy-modified, carboxyl-modified, carbinol-modified, methacryl-modified, mercapto-modified, phenol-modified, polyether-modified, methylstyryl-modified, alkyl-modified and higher fatty acid ester-modified silicone oils, silicone modifiers, etc. It is also preferably used. The dispersant composed of a silane compound such as chlorosilane and alkoxysilane, a silane coupling agent, various modified silicone oils and silicone modifiers may be used alone or in combination of two or more.

The amount of the silane compound added is preferably 0.01 to 20 parts by weight, based on 100 parts by weight of the thermoplastic resin. When the addition amount is less than 0.01 parts by weight, the conductive aniline-based polymer fine particles and the conductive inorganic-based powder are not sufficiently dispersed in the resin component, and the heat generation property during fusion is deteriorated. The mechanical strength at the fusion-bonded part of the obtained molded body is reduced. On the other hand, if the above-mentioned addition amount exceeds 20 parts by weight, the fusion strength of the obtained molded product will be reduced.

The method of adding the silane compound is not particularly limited, but for example, the molten thermoplastic resin, the conductive aniline polymer fine particles and the conductive inorganic powder are mixed. At this time, these components may be added and mixed at the same time, but they may be mixed only with the conductive aniline-based polymer fine particles or the conductive inorganic-based powder to prepare the conductive aniline-based polymer in advance. The surface of the fine particles or the electrically conductive inorganic powder may be pretreated and then added to and mixed with the thermoplastic resin.

The method of pretreating the surface of the conductive aniline polymer fine particles or the conductive inorganic powder with the silane compound is not particularly limited. For example, the conductive aniline polymer is used. While conducting high-speed stirring of polymer fine particles or conductive inorganic powder with a high-speed stirrer such as a Henschel mixer or a super mixer (both are trademarks), the silane compound or the silane compound-containing solution is dropped or sprayed to make the conductive The method of adding the aniline-based polymer fine particles or the conductive inorganic-based powder so as to form a film on the surface thereof, uniformly mixing, and then drying to volatilize the contained solvent and the like.

The microwave fusion resin composition of the present invention prepared as described above may be used, for example, as a material for molding the entire molded body having the joint portion of the thermoplastic resin pipe joint. It may be used by embedding it in the molded body or exposing it to the surface only in a portion of the thermoplastic resin molded body that requires joining, for example, by an insert method by injection molding or a laminating method by a laminator. or,
For example, in butt joining in which pipe ends of a thermoplastic resin pipe are abutted against each other and fused, microwave fusion when sandwiching an annular sheet to the abutting surface of the thermoplastic resin pipe in accordance with the end face of the pipe end is performed. It may be used as a worn resin sheet.

As a microwave power source used for fusing a thermoplastic resin molding to be joined using the resin composition for microwave fusion of the present invention, for example, a commercial frequency of 2.
45 GHz and power of 100 to 2000 W are used.

The irradiation time of the microwave varies depending on the size and shape of the thermoplastic resin moldings to be bonded, but, for example, a medium density polyethylene pipe for gas is used on the inner surface of a pipe joint made of the same material as the microwave. When the resin sheet for wave fusion is joined to a microwave fusion pipe joint which is embedded and fused, the microwave is irradiated by a dedicated microwave irradiator, and the irradiation time for completing the fusion is 10 Seconds ~
180 seconds.

The microwave fusion resin composition of the present invention comprises:
Since it is configured as described above, the conductive aniline polymer fine particles and the conductive inorganic powder are finely dispersed in the thermoplastic resin, and obtained from the microwave fusion resin composition. The molded article for bonding has a heat generation characteristic in a low temperature range and a high temperature range of about 200 ° C. of the conductive aniline-based polymer fine particles and the conductive inorganic-based powder when dielectric heating is performed by irradiating microwaves. Complementarily and stably, the temperature of the thermoplastic resin molding to be joined can be uniformly and efficiently raised, and the thermoplastic resin molding to be joined can be formed without deterioration of the thermoplastic resin due to partial overheating. Fuse together.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.

(Example 1) Medium density polyethylene (manufactured by Mitsui Petrochemical Co., Ltd., 190 ° C., 2.16 kg, MFR = 0.2)
g / 10 min) 100 parts by weight, conductive aniline-based polymer particles (manufactured by Allied Signal Co., trade name: Vers)
30 parts by weight of iron) and 20 parts by weight of antimony oxide-containing tin oxide powder (manufactured by Mitsubishi Materials Corporation) were kneaded at 160 ° C. with a Brabender Plastograph (manufactured by Toyo Seiki Co., Ltd.) to prepare a resin composition for microwave fusion. .

The obtained microwave fusion resin composition was molded into a sheet having a thickness of 0.5 mm by a press molding machine, and 2
A 0 mm × 10 mm test piece was cut out, and scissors were inserted between two strips of the medium-density polyethylene having a thickness of 4 mm and 10 mm × 80 mm, and a microwave (2. 45 GHz, 50
0 W) to irradiate the medium-density polyethylene strip-shaped sheets to each other.

The medium-density polyethylene strip-shaped sheet fused with the test piece was set to 50 mm by a tensile tester.
A peeling test was performed at a tensile speed of / min to measure the peeling strength to obtain a peeling strength of 12.6 kgf / cm.

(Example 2) Barium sulfate powder (manufactured by Mitsui Kinzoku Co., Ltd.) 20 coated with antimony-doped tin oxide instead of the tin oxide powder containing antimony oxide of Example 1 20
A resin composition for microwave fusion was prepared in the same manner as in Example 1 except that parts by weight were used. As in Example 1,
A test piece was prepared from the obtained resin composition for microwave fusion, and the medium-density polyethylene strip-shaped sheets were fused to each other using the test piece. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 1 to obtain a peel strength of 12.8 kgf / cm.

Example 3 Microwave fusion was carried out in the same manner as in Example 1 except that 10 parts by weight of carbon black (manufactured by Mitsubishi Chemical Co., Ltd.) was used in place of the tin oxide powder containing antimony oxide of Example 1. A resin composition was prepared. Example 1
Similarly to the above, a test piece was prepared from the obtained resin composition for microwave fusion, and a strip sheet of medium density polyethylene was fused to each other using the test piece. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 1 to obtain a peel strength of 14.5 kgf / cm.

(Example 4) A resin composition for microwave fusion was prepared in the same manner as in Example 3 except that the amount of the conductive aniline polymer fine particles added in Example 3 was changed from 20 parts by weight to 30 parts by weight. The thing was made. In the same manner as in Example 3, a test piece was prepared from the obtained resin composition for microwave fusion, and the medium-density polyethylene strip-shaped sheets were fused to each other using the test piece. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 1 to obtain a peel strength of 13.7 kgf / cm.

Example 5 The amount of conductive aniline-based polymer particles added in Example 3 was changed from 20 parts by weight to 60 parts by weight, and the amount of carbon black added was changed from 10 parts by weight to 5 parts by weight.
A resin composition for microwave fusion was prepared in the same manner as in Example 3 except that the weight part was changed. In the same manner as in Example 3, a test piece was prepared from the obtained resin composition for microwave fusion, and the medium-density polyethylene strip-shaped sheets were fused to each other using the test piece. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 1 to obtain a peel strength of 10.1 kgf / cm.

Example 6 In place of the medium-density polyethylene resin of Example 4, a high-density polyethylene resin (Mitsui Petrochemical Co., Ltd., 190 ° C., 2.16 kg, MFR = 0.1 g /
Example 4 except that 100 parts by weight of 10 min) was used.
A resin composition for microwave fusion was prepared in the same manner as in.
A test piece was prepared from the obtained resin composition for microwave fusion in the same manner as in Example 4, and the medium-density polyethylene strip-shaped sheets were fused to each other using the test piece. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 4 to obtain a peel strength of 13.9 kgf / cm.

Comparative Example 1 100 parts by weight of the medium-density polyethylene of Example 1 and conductive aniline polymer fine particles 6 were used.
0 parts by weight were mixed in the same manner as in Example 1 to prepare a resin composition for microwave fusion. In the same manner as in Example 1, test pieces were prepared from the obtained resin composition for microwave fusion, and strips of medium-density polyethylene were fused to each other using the test pieces. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 1 to obtain a peel strength of 6.4 kgf / cm.

(Comparative Example 2) A resin composition for microwave fusion was prepared in the same manner as in Example 5, except that the amount of the conductive aniline-based polymer particles added in Example 5 was changed from 60 parts by weight to 3 parts by weight. The thing was made. A test piece was prepared from the obtained resin composition for microwave fusion in the same manner as in Example 5, and it was attempted to fuse the medium-density polyethylene strip-shaped sheets to each other using the test piece, but the calorific value was insufficient. It didn't fuse.

Comparative Example 3 A resin composition for microwave fusion was prepared in the same manner as in Example 3 except that the amount of conductive aniline polymer fine particles added in Example 3 was changed from 20 parts by weight to 150 parts by weight. The thing was made. A test piece was prepared from the obtained resin composition for microwave fusion in the same manner as in Example 3,
Strips of medium density polyethylene were fused together using the test pieces. The peel strength of the fused medium-strength polyethylene strip sheet was measured in the same manner as in Example 3 to obtain a peel strength of 1.4 kgf / cm.

Comparative Example 4 100 parts by weight of the medium-density polyethylene of Example 1 and 30 parts by weight of carbon black of Example 3 were mixed in the same manner as in Example 1 to prepare a resin composition for microwave fusion. . In the same manner as in Example 1, a test piece was prepared from the obtained resin composition for microwave fusion and an attempt was made to fuse the medium-density polyethylene strip-shaped sheets to each other using the test piece. At some time, the resin composition for microwave fusion partially ignited and could not be fused.

Table 1 shows the evaluation results of Examples 1 to 6 and Comparative Examples 1 to 4. In the table, medium density polyethylene is abbreviated as MDPE, high density polyethylene is abbreviated as HDPE, and conductive aniline-based polymer particles are abbreviated as polyaniline.
Further, the types of conductive inorganic powders are listed in Table 1 by the following abbreviations.

SnO: antimony oxide-containing tin oxide powder BaSO ₄ : barium sulfate powder coated with antimony-doped tin oxide CB: carbon black

[0046]

[Table 1]

[0047]

Since the resin composition for microwave fusion of the present invention is constructed as described above, the conductive aniline polymer fine particles and the conductive inorganic powder are contained in the thermoplastic resin. The molding for bonding which is finely dispersed and is obtained from the resin composition for microwave fusion is a conductive aniline-based polymer fine particle and a conductive inorganic-based powder when the dielectric heating is performed by irradiating microwaves. The heat generation characteristics of the low temperature region and the high temperature region of which the temperature is about 200 ° C as a boundary are complementary to each other, and the temperature of the thermoplastic resin molding to be joined is uniformly and efficiently raised to the partial melting temperature. The thermoplastic resin moldings to be joined are fused together without deterioration of the thermoplastic resin due to.

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Claims (1)

[Claims] 1. A conductive aniline polymer fine particle comprising 100 parts by weight of a thermoplastic resin, 5 to 100 parts by weight of conductive aniline polymer fine particles and 3 to 50 parts by weight of conductive inorganic powder. A resin composition for microwave fusion, characterized in that the content is higher than the content of the electrically conductive inorganic powder.