JPS60147408A - Electrically conductive material - Google Patents

Abstract

PURPOSE:An electrically conductive material, containing a polymer, etc. obtained by incorporating a specific polyoxyalkylene acrylate with an electrically conductive filler, and polymerizing the resultant mixture as an essential component, having a low softening point, good processability and little thermal energy loss, and useful as heating sheets, etc. CONSTITUTION:An electrically conductive material, e.g. electrically conductive film, obtained by incorporating a monomer expressed by the formula (R1 is ethyl or methyl; R2 is H, methyl or ethyl; R3 is H, 1-25C alkyl, 1-25C aralkyl, phenyl, 1-25C alkylaryl or 1-25C acyl; n is 10-10,000) with an electrically conductive filler, and polymerizing the resultant mixture, or polymerizing the monomer and incorporating the resultant polymer with the electrically conductive filler, and molding the resultant material containing the above-mentioned polymer as an essential component by hot-pressing, etc.

Description

[Detailed description of the invention] The present invention relates to electrically conductive materials.

＼ Various conductive materials have been announced so far, such as polymer materials containing conductive fillers and materials whose resin itself is conductive, such as antistatic materials, power cables, surface heating elements,
It is used in many applications such as conductive paint, electromagnetic shielding material, and electroplating. Note that conductivity as used herein means a property of resistivity of 10Ω·C11 or less.

However, as mentioned above, the conductive materials used from the beginning have a high softening point and when mixed with conductive fillers,
It requires high temperature, takes a long time to obtain a uniform resin, and has drawbacks such as high energy loss when used in a surface heating element.

In view of the above circumstances, the present inventors have conducted extensive research to obtain a conductive material that does not have the above-mentioned drawbacks, has a low softening point, and has little loss of thermal energy, and as a result, has come to provide the present invention. It is. That is, a polymer obtained by blending and polymerizing a monomer represented by the general formula (I) (hereinafter referred to as a monomer represented by the general formula (1)) with a conductive filler, or a polymer obtained by polymerizing the monomer represented by the general formula (I) This is a conductive material characterized by having as an essential component a polymer obtained by polymerizing the monomer represented by the following alone and blending a conductive filler with the polymer.

In the present invention, the monomer represented by general formula (I) is, for example, (1) a compound obtained by addition-reacting an alkylene oxide to acrylic acid or methacrylic acid, or (2) a compound obtained by subjecting acrylic acid or methacrylic acid to a polyalkylene gel. Examples include compounds obtained by esterification reaction with a monosubstituted product of Recall.

Examples of the alkylene oxide include ethylene oxide, -propylene oxide, butylene oxide, etc.
(1) Examples of the addition type include a single type or two or more types of pro-nk type or random type.

Examples of monosubstituted polyalkylene glycols include methyl alcohol, ethyl alcohol, butyl alcohol, and octyl alcohol.
r D −) Lt・′″7°′Jj′7.

Examples include compounds in which the alkylene oxide is added to a starting material such as alcohol, benzyl alcohol, phenol, nonylphenol, butylphenol, caprylic acid, lauric acid, or oleic acid.

In all of the above cases, the number of moles of alkylene oxide added is from 10 to 10,000, and if it deviates from this range, the object of the present invention will not be achieved.

Next, the monomer represented by general formula (I) is produced according to a known manufacturing method. Furthermore, the monomer represented by the general formula (I) may be produced according to a method other than the "-" configuration.

Polymerization of the monomer represented by general formula (I) is carried out using a conventional radical-generating catalyst, heat, or ultraviolet light, but when polymerizing after blending a conductive filler, heat is preferably carried out.

Examples of the conductive filler used in the present invention include gold,
Examples include powders, flakes, voice cars, fibers, etc. manufactured from metals such as silver, nickel, copper, iron, aluminum, and zinc, and carbon-based powders and fibers such as acetylene black, furnace black, graphite, and carbon ta fibers. . These conductive fillers are selected and used in terms of conductivity, cost, appearance, etc.

The amount of the conductive filler to be blended is preferably 10 to 200 parts with respect to 100 parts (parts by weight, hereinafter the same) of the monomer or polymer thereof represented by general formula (I), and is determined depending on the type of filler.

The monomer represented by general formula (I) or its polymer can be mixed with the conductive filani by a conventional method, such as kneading with rolls or using a Banbury mixer. For example, as a method using a roll, 80
A preferred method is to gradually add the conductive filler to the monomer represented by formula (I) or its polymer heated to about 120 parts while kneading.

The conductive material of the present invention has good conductivity and can be handled at a relatively low temperature of approximately 70° C. or higher. In addition, when carbon-based powder is used as a conductive filler, the conductive material has good conductivity at temperatures below about 80 to 70°C (conductivity with a resistance value of 10 to 103 Ω·cm with 30 parts of acetylene black).
When the temperature exceeds about 60 to 70°C, the resistance value increases significantly due to the so-called PTC effect, so that it can function as a thermostat.

Since the conductive material of the present invention has the above characteristics,
It can be used in a wide range of applications such as surface heating elements, antistatic materials, thermal sensors, and conductive paints.

Next, the conductive material of the present invention will be explained based on Examples.

Production Example 1 In a 2fL four-eye flask equipped with a stirrer, add 10Hg (1 mole) of a 20 mole adduct of lauryl alcohol EO as a monosubstituted polyalkylene glycol! Prepare #10g,
Dissolve and stir at an internal temperature of 95°C.

Next, 72 g (1 mol) of acrylic i was gradually introduced dropwise. The dropwise addition took about 1 hour, and after aging for about 30 minutes, the solution was cooled to 70% and neutralized with 8 g of a 50% aqueous solution of caustic soda.

Next, dehydration and filtration were performed to obtain monomer (a) represented by general formula (1).

Similarly, as shown in Table 1, monomers (b), (d) and (e) represented by general formula (I) were obtained.

Production Example 2 130 g (1 mol) of hydroxyethyl methacrylate sufficiently dehydrated in a 4-liter autoclave and 4.13 mol of metallic Na
Prepare g1. Heat to 120°C under reduced pressure. Next, a mixture of 1160 g (20 moles) of propylene oxide and 17113 g (39 moles) of ethylene oxide is introduced. Complete the introduction while keeping the reaction pressure below 2.0 kg/cc. Next, ripen at 120°C for about 30 minutes. Second, cool to 50°C and neutralize with 12 g of acetic acid.

As shown in Table 1, a monomer (c) represented by general formula (I) was obtained.

Examples 1 to 1O The conductive filler shown in Table 2 was kneaded into 100 parts of the monomer of the general formula (I) obtained in the production example at 80°C with a heated roll, and then After curing for 1 hour at 12'0'9, a conductive material was obtained.

1. Using the conductive material obtained, 80 te, 40-0 kg
/ cm', and was hot pressed for 3 minutes to obtain a conductive film with a thickness of 0.1cm, 10cra in the vertical direction, and 5C layers in the horizontal direction.

The tensile strength, elongation, tear strength, electrical resistance, and softening point of the obtained film were measured based on the following methods. The results are shown in Table 2. 'Tensile strength, elongation and tear strength are JI
Measured according to SK-8301 and JIS K-87ElO. The electrical resistance was measured by pressing and attaching copper foil to the diagonal ends of the rectangle and using a resistance meter. Softening point is JIS K
-7208.

In Table 2, Denka Black used was acetylene black granules manufactured by Denki Kagaku Kogyo (■), and reagents were used for silver powder, gold powder, aluminum flakes, and graphite.

Examples 11-15 Represented by general formula (I) obtained in Production Example. monomer 10
0 part, 0.1 part of azobisin butyronitrile was uniformly blended and polymerized in a constant temperature machine at 50 to 70°C for 2 hours.

The same procedure as in Example 1 was carried out using the obtained polymer. A conductive material was obtained.

The results are shown in Table 3.

Claims (1)

[Scope of Claims] A polymer obtained by blending and combining a conductive filler with a monomer represented by the general formula (I) (hereinafter referred to as the monomer represented by the general formula (I)), Or a conductive material characterized by having as an essential component a polymer obtained by polymerizing the monomer represented by the general formula (I) alone and blending a conductive filler with the polymer.