JPH09316358A - Encapsulation product of inorganic material using conjugated alkene, its production, and resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an encapsulation product of an inorg. material which product has capsules formed from a conjugated alkene, has excellent impact characteristics, and imparts, when compounded into a thermoplastic resin, a function corresponding to that of the inorg. material to the resin, a process for producing the same, and a resin compsn. contg. the same. SOLUTION: This encapsulation product is formed by coating an inorg. material with a 4-10C conjugated alkene. This process for producing an encapsulation product of an inorg. material comprises dispersing the inorg. material in water and polymerizing a conjugated alkene in the water to coat the material. The product is compounded into a thermoplastic resin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an inorganic material encapsulated product obtained by coating an inorganic material with a conjugated alkene, a method for producing the same, and a resin composition.

This inorganic material capsule is a material that can be expected to strengthen and modify the resin and to impart various functions such as conductivity by blending with the resin.

[0003]

2. Description of the Related Art Conventionally, inorganic materials have been used for reinforcing and modifying resins, and various functions such as conductive powder such as carbon black and graphite for imparting conductivity to the resin, and magnetic powder such as ferrite. In order to impart magnetism to the resin, molybdenum disulfide and the like are added to the resin to impart slidability to the resin.

As these inorganic materials, crushed materials are generally used as they are, or surface-treated with an organic acid or the like to prevent aggregation of fine particles. It has poor affinity and it is difficult to disperse it evenly when kneading and dispersing it in a resin.
It was necessary to increase the blending amount in order to cause variations in products, to fail to fully exhibit the prescribed performance, and to exert the prescribed performance.

Therefore, the applicant of the present invention has conducted research based on the recognition that the surface of the inorganic powder is covered with a resin, that is, the affinity with the resin can be remarkably improved by encapsulating the inorganic powder, and talc or carbon A method of encapsulating an inorganic powder such as black or graphite with an ester of acrylic acid or methacrylic acid, or styrene was found, and proposed as a surface treatment method for various inorganic powders (JP-A-7-2287).
95 or Japanese Patent Application No. 7-306404).

[0006] However, this type of encapsulated product has excellent dispersibility when blended with other resins, so that even a small amount of blended product
Various functions such as conductivity, magnetism, and slidability are added according to the function of the inorganic material, but generally rigidity (tensile strength, bending strength, bending elastic modulus, etc.) is improved, and in a form that is contrary to this. However, it has a drawback that the impact strength is lowered and the flexibility of the resin is lost.

[0007]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a function according to the function of an inorganic material when compounded with another type of thermoplastic resin, that is, a heterogeneous thermoplastic resin. And an encapsulated inorganic material coated with a polymer of a conjugated alkene having excellent impact properties, a method for producing the same, and a resin composition.

[0008]

In order to achieve the above object, the present inventor has made earnest studies on selection of a monomer to be used and surface treatment. As a result, the present inventors have found that the presence of an inorganic material has 4 to 10 carbon atoms. By polymerizing conjugated alkenes, the surface of the inorganic material is coated with these polymers to obtain a capsule-shaped inorganic material capsule, which functions as an inorganic material when kneaded with another resin. It was found that it contributes to the improvement of impact strength as well as being imparted to the resin,
The present invention was conceived.

That is, according to the present invention, the inorganic material is made to have 4 carbon atoms.
10 to 10 encapsulated inorganic material consisting of a polymer of a conjugated alkene polymer and an inorganic material dispersed in water, and having 4 to 1 carbon atoms in the presence of an oil-soluble polymerization initiator.
The present invention relates to a method for encapsulating an inorganic material, which comprises polymerizing a conjugated alkene of 0 with styrene in the water to coat the inorganic material, and a resin composition comprising the inorganic material mixed with a thermoplastic resin. Is.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION As the above-mentioned inorganic material of the present invention,
Any material that can be generally blended with a resin or the like can be used without any problem, and the size of this material may be one that is generally used as a filler for resin, and is 0.01 to 1000 μm. Can be appropriately selected within the range.
Furthermore, the shape of this material does not necessarily have to be spherical, and plate-shaped, rod-shaped, fiber-shaped, and dice-shaped materials can also be used. Specifically, reinforcing materials such as talc, mica and silica, modifying materials, metal powders and metal fibers such as copper and nickel, conductive materials such as carbon black, graphite and carbon fibers, magnetic materials such as ferrite, Sliding materials such as molybdenum sulfide are suitable for the present invention.

Examples of conjugated alkenes having 4 to 10 carbon atoms are 2-methyl-1,3-butadiene, 2,4-pentadiene, 2-methyl-1,3-pentadiene, and 3-methyl-1,3.
Examples include -pentadiene and 2,5-dimethyl-2,4-hexadiene. Polymers having 3 or less carbon atoms are complicated in polymerization operation in the coexistence with an inorganic material, and those having 11 or more carbon atoms are difficult to obtain and are not economical. Particularly, it is preferable to use a conjugated alkene having 5 to 6 carbon atoms. These alkenes may be used alone or in combination of two or more.

In order to encapsulate this inorganic material,
First, it is possible to disperse an inorganic material in water, add a conjugated alkene having 4 to 10 carbon atoms and a polymerization initiator while stirring this, and continue stirring to carry out a polymerization reaction.

In this case, the ratio of the inorganic material and water is 0.5 /
It may be appropriately selected within the range of 1 to 1/50. Further, in order to improve the dispersibility of the inorganic material, it is preferable to add a surfactant such as sodium oleate at a concentration of 1 × 10 ⁻⁴ to 1 × 10 ⁻² mol / l.

Examples of the oil-soluble polymerization initiator include organic peroxides such as benzoyl peroxide and 2,2'-azobis (isobutyronitrile) (AIBN), which have low reactivity at low temperature. It is desirable to use the excellent benzoyl peroxide. The amount of this polymerization initiator used cannot be unconditionally determined because it varies depending on the amounts of the inorganic material and the conjugated alkene, but the concentration in the reaction solution is 1 × 10 ^{−4 to} 5 ×.
It may be appropriately selected within the range of 10 ^-1 mol / l.

The polymerization reaction temperature may be from room temperature to 100 ° C, which is the boiling temperature of water, but is preferably in the range of 40 to 90 ° C from the viewpoint of operability and reactivity. The reaction time is affected by the concentration of the polymerization initiator and the reaction temperature, but 30 minutes to 6 hours is sufficient.

In this encapsulation reaction, by controlling the reaction conditions, the polymerization amount of the conjugated alkene (resin content:% by weight relative to the total amount of the inorganic material encapsulated product of the polymer by the conjugated alkene) is arbitrarily set. Can be changed. It is particularly preferable that the resin content is 50% by weight or less, because aggregation of the encapsulated product does not occur when compounded with the resin and handling becomes easy. Further, in order to obtain the remarkable effect of the present invention, the resin content is preferably 0.1% by weight or more.

The inorganic material obtained by the above method has 4 to 4 carbon atoms.
The conjugated alkene encapsulation product of 10 is a resin film having a relatively uniform thickness formed on the surface of an inorganic material. When this is mixed with a resin, the inorganic material is inside a molded article of the resin composition. To evenly disperse.

The encapsulated material of the inorganic material can be directly molded by press molding or injection molding to be a molded product of the resin composition. Further, by mixing this encapsulated material with another resin, A resin composition can be obtained. Resins suitable for blending the encapsulated product in this case are thermoplastic resins having relatively low polarity such as polyethylene, polypropylene, polystyrene and ABS resin. The compounding amount of this encapsulated product in the resin is 9
It can be arbitrarily compounded up to about 0% by weight, and may be appropriately selected and compounded in accordance with the required values of physical properties. When blending and kneading the encapsulated product with other resins, generally used when blending various inorganic materials and the like with resins, a single-screw kneading extruder,
A twin-screw kneading extruder, a Banbury mixer, a pressure kneader, etc. can be used as they are.

[0019]

Example 1 90 g of expanded graphite having a particle size of 100 to 600 μm (EXP-P manufactured by Nippon Graphite Industry Co., Ltd.), 300 ml of distilled water, 10 mg of sodium oleate, and 10 parts of ferrous ammonium sulfate.
mg was added, the temperature was raised to 35 ° C. under stirring in a nitrogen gas atmosphere, and then a solution of 10 mg of benzoyl peroxide in 5 g of 2-methyl-1,3-butadiene was added dropwise over about 30 minutes. After completion of dropping, the mixture was stirred for 6 hours, filtered off, the solid was sufficiently washed with distilled water and methanol, and dried under reduced pressure to obtain expanded graphite capsules. The resin content of this expanded graphite capsule is
It was 4% by weight.

Example 2 A ferrite capsule was obtained by conducting the same experiment as in Example 1 except that the expanded graphite was changed to strontium ferrite (manufactured by Hokuko Denshi KK). The resin content of this ferrite capsule is 4
% By weight.

(Example 3) Polypropylene (manufactured by Mitsubishi Chemical Co., Ltd., Diapolymer 4800JG) was blended with the expanded graphite capsule obtained in Example 1 so that the expanded graphite amount was 20% by weight based on the polypropylene. Kneading was carried out using a small kneader (EK-350, manufactured by Toseki Seimitsu Kogyo KK).

The resulting resin composition is injection-molded to
A plate-shaped test piece of 8 cm x 1 cm x 3 mm was formed, and both ends were 1.5c.
m was cut off, the cut surface was polished, and processed into a test piece of 5 cm x 1 cm x 3 mm. After that, after applying silver paste to the cutting surface to make an electrode, measure the resistance value using a tester,
It was converted to volume resistivity. As a result, the specific volume resistivity was 6 Ω · cm. Moreover, the Izod impact strength (by the method specified in JIS K7110) was measured using the injection-molded test piece. As a result, the impact strength is 4.0kgf
It was cm / cm ² .

(Comparative Example 1) Expanded graphite 9 used in Example 1
To 0 g, 300 ml of distilled water and 10 mg of sodium oleate were added, and the temperature was raised to 35 ° C. under stirring in a nitrogen gas atmosphere, then 2-methyl-1,3-butadiene 9 g and a 6% aqueous solution of sulfite as a polymerization initiator 4. Except that 1 g was dropped separately.
The same operation as in Example 1 was performed, but no expanded graphite capsule was obtained.

(Comparative Example 2) In Comparative Example 1, except that 0.8 g of 2,2'-azobis (isobutylamidine) dihydrochloride (AIBA) dissolved in distilled water was used as a polymerization initiator. The same operation as in Example 1 was performed, but no expanded graphite capsule was obtained.

Comparative Example 3 The procedure of Example 3 was repeated except that the unencapsulated expanded graphite was blended in an amount of 20% by weight based on polypropylene. The strength was measured. As a result, the volume resistivity is 1.3 × 10 ² Ω · c
m, Izod impact strength was 2.6 kgfcm / cm ² .

(Comparative Example 4) Expanded graphite 3 used in Example 1
0g to 600ml distilled water, 173m sodium dodecyl sulfate
g was added and the temperature was raised to 80 ° C. with stirring under a nitrogen gas atmosphere, and then a solution prepared by dissolving 986 mg of AIBN in 6 g of styrene was added dropwise over about 3 hours. After completion of dropping, the mixture was stirred for 1 hour, and hydroquinone was added to stop the polymerization reaction. After completion of the reaction, the mixture was cooled to room temperature, filtered, and the solid was sufficiently washed with distilled water and methanol and dried under reduced pressure to give a resin content of 12
A wt% expanded graphite capsule was obtained.

Next, this expanded graphite capsule was blended in the same manner as in Example 3 so that the amount of expanded graphite was 20% by weight with respect to polypropylene, and injection molding was performed to prepare a test piece. The modulus and Izod impact strength were measured. As a result, the volume resistivity was 10 Ω · cm and the Izod impact strength was 1.2 kgfcm / cm ² .

From the above results, it can be seen that the encapsulant of the present invention, when added to a resin, imparts functionality and improves impact strength, and a resin composition having excellent flexibility can be obtained.

[0029]

INDUSTRIAL APPLICABILITY The inorganic material capsule of the present invention, when added to a thermoplastic resin, imparts a function corresponding to the function of the inorganic material and can produce a resin composition having excellent impact properties. Play.

Claims (3)

[Claims] 1. An encapsulated inorganic material, which is obtained by coating an inorganic material with a conjugated alkene having 4 to 10 carbon atoms. 2. An inorganic material encapsulated product, which comprises dispersing an inorganic material in water and polymerizing a conjugated alkene in the water in the presence of an oil-soluble polymerization initiator to coat the inorganic material. Production method. 3. A resin composition comprising the inorganic material capsule according to claim 1 and a thermoplastic resin.