JP2003253132A - Low-friction high-dispersion synthetic resin composition containing fine powder of rbc or crbc, and its production process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-friction high-dispersion synthetic resin composition which can realize uniform dispersion of various additives. <P>SOLUTION: The low-friction high-dispersion synthetic resin composition is obtained by dispersing a fine powder of an RB ceramic (referred to as RBC) comprising a carbonaceous material obtained by kneading a mixture of a degreased rice bran, obtained from a rice bran, and a thermosetting resin, press molding the kneaded material to give a molding, drying the molding, and baking the dried molding in an inert gas atmosphere, or a fine powder of a CRB ceramic (referred to as CRBC), which is a modification of the RBC, in a synthetic resin. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a low-friction, high-dispersion synthetic resin composition capable of uniformly dispersing various additives in a resin. 900,000 tons / year in Japan,
It is known from a study by Kazuo Horikirikawa, the first inventor of the present invention, to try to obtain a porous carbon material by using rice bran, which is discharged 33 million tons / year all over the world. (Functional Materials May 1997 Vol. 17
No. 5 p24-28) Here, a defatted bran obtained from rice bran and a thermosetting resin are mixed and kneaded, and the pressure-molded molded body is dried, and then the dried molded body is subjected to an inert gas atmosphere. RB ceramics (hereinafter referred to as RBCs), which is a carbon material fired therein, and a manufacturing method thereof are shown. The thermosetting resin may be any one as long as it is thermoset, and typically, a phenol resin, a diaryl phthalate resin, an unsaturated polyester resin, an epoxy resin, a polyimide resin,
Examples include triazine-based resins. Particularly, a phenol resin is preferably used. The mixing ratio of the degreased bran and the thermosetting resin is 50 to 90:50 to 10 by mass, and preferably 75:25 is used. The firing temperature is
The temperature is 700 to 1000 ° C., a rotary kiln is usually used, and the firing time is about 40 to 120 minutes.
CR, which is a carbon material obtained by further improving RB ceramics
B ceramics (hereinafter referred to as CRBC) is an RB obtained from a degreased bran obtained from rice bran and a thermosetting resin.
An improved ceramic material, a degreased bran obtained from rice bran and a thermosetting resin are mixed and kneaded, followed by primary firing in an inert gas at 700 ° C to 1000 ° C, and then pulverization to about 100 mesh or less. To form a carbonized powder, and the carbonized powder and a thermosetting resin are mixed and kneaded, and the pressure is 20 MPa to 30 M.
It is a black resin or porous ceramics obtained by press-molding at Pa and then heat-treating the molded body again at 500 ° C. to 1100 ° C. in an inert gas atmosphere.

RBC and CRBC have the following excellent features.・ High hardness.・ The shape of the particles is distorted. -The coefficient of expansion is very small. -The organizational structure is porous.・ Has electrical conductivity.・ Small and light weight.・ The coefficient of friction is very small.・ Excellent wear resistance. -Since the material is rice bran, it has little adverse effect on the global environment, leading to resource conservation. In the present invention, RBC and CRBC have an average particle size of 3
The present invention relates to a low-friction / high-dispersion synthetic resin composition obtained by finely pulverizing it to a particle size of 00 μm or less, preferably 10 to 100 μm, and more preferably 10 to 50 μm and mixing it with a synthetic resin.

[0003]

2. Description of the Related Art Conventionally, various fillers such as stabilizers, antioxidants, colorants, antistatic agents, ultraviolet absorbers, lubricants, flame retardants, and other fillers have been added to synthetic resin compositions. However, it is difficult to uniformly disperse stabilizers, antioxidants, colorants, antistatic agents, ultraviolet absorbers, lubricants, flame retardants, and other fillers in the resin due to differences in polarity, solubility and specific gravity. It was

[0004]

The present inventor has found that when various additives are dispersed in various synthetic resins, if the additives that cannot be well dispersed in the resin are RB ceramics and / or CR.
The fact that the presence of fine powder of B ceramics exhibits high dispersibility in which stabilizers, antioxidants, colorants, antistatic agents, UV absorbers, lubricants, flame retardants, and other body fillers are more evenly dispersed. In addition, the inventors found that the friction coefficient was lower than that of a synthetic resin composition containing fine powder of RB ceramics and / or CRB ceramics and a synthetic resin composition containing no fine powder of RB ceramics and completed the present invention. Came to. The bulk specific gravity of RB ceramics and / or CRB ceramics is about 1.22 to 1.35 (g · cm ⁻³ ).
(For bulk specific gravity, the JIS R 1601.4 test piece
IS R 7222.7 The bulk specific gravity was measured by the measuring method. Since RB ceramics and / or CRB ceramics are porous, only bulk specific gravity can be measured. ) And RB made into a fine powder
It was found that a low-friction and high-dispersion synthetic resin composition can be obtained by using ceramics and / or CRB ceramics dispersed in a resin. Further, another object of the present invention is to increase the content of the RB ceramics and / or CRB ceramics fine powder, so that the low-friction / high-dispersion synthetic resin composition becomes electrically conductive. The purpose is to provide things.

[0005]

The present inventor has found that RBC (R
B ceramics) or CRBC (CRB ceramics)
Surprisingly as a result of intensive research focusing on the specificity of RBC or CRBC, fine powders of RBC or CRBC were found to be stabilizers, antioxidants, colorants, antistatic agents, UV absorbers, lubricants, flame retardants, and other constitutions. It has been found that even if the filler or the like is hydrophilic or lipophilic, it has the property (high dispersibility) that it can be uniformly dispersed in the synthetic resin. We have not fully clarified why such a phenomenon occurs, but probably RBC
It is assumed that (RB ceramics) or CRBC (CRB ceramics) is a porous carbon body having an inorganic substance such as phosphorus (P) and potassium (K). At the same time, RBC (RB ceramics) or CR
It was also found that when a fine powder of BC (CRB ceramics) is contained in a synthetic resin and molded, a resin molded product having a surface with low friction characteristics can be obtained. A typical method for producing the low-friction / high-dispersion synthetic resin composition of the present invention is a fine powder of RBC or CRBC, a stabilizer, an antioxidant, a colorant, an antistatic agent, an ultraviolet absorber, a lubricant, and RBC or CRB is prepared by premixing at least one additive selected from the group consisting of flame retardants and other extender fillers, and then adding the mixture at a temperature near the melting point of the synthetic resin and kneading the mixture.
It is easily obtained by uniformly dispersing the fine powder of C and the additive.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The fine powder of RBC or CRBC used in the present invention has an average particle diameter of 300 μm or less. Particularly, those having an average particle size of 10 to 100 μm, more preferably 10 to 50 μm are suitable as a low friction and high dispersive synthetic resin composition.

The synthetic resin which can be used in the present invention includes thermoplastic resins such as polyamide, polyester and polyolefin. Specifically, nylon 66 (polyhexamethylene adipamide), nylon 6 (polycapramide), nylon 11 (polyundecane amide), nylon 12, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polypropylene, polyethylene, polyphenylene sulfide, etc. A thermoplastic resin may be used. Especially nylon 6
6 is preferably used. These thermoplastic resins may be used alone or in combination of two or more.

Further, a thermosetting resin may be used in combination without departing from the scope of the present invention. Examples of such thermosetting resins include phenolic resins, diarylphthalate resins, unsaturated polyester resins, epoxy resins, polyimide resins, triazine resins and the like. As long as there is no problem in the compatibility of the resins with each other, one or two or more of them can be added in an amount of about 20% by mass or less of the total resin composition. In the present invention, the addition ratio of the synthetic resin is RBC or CRBC.
Mass ratio of fine powder to synthetic resin is 5 to 90:95 to 10
Is desirable. If the addition ratio of the synthetic resin exceeds 95% by mass, the low friction / dispersion properties are deteriorated, and if it is 10% by mass or less, molding becomes difficult. Further, in order to impart conductivity to the synthetic resin composition, it is necessary that the mass ratio of fine powder of RBC or CRBC: synthetic resin is 35 to 90:65 to 10.

As the stabilizer used in the present invention, a heat stabilizer represented by a phosphoric acid ester or a phosphorous acid ester or a light stabilizer includes a hindered amine light stabilizer, a phenylbenzoate light stabilizer, There are nickel complex salts. As a specific example of the hindered amine-based or phenylbenzoate-based light stabilizer, bis (2,2
2,6,6-tetramethyl-4-piperidyl) sepacate, succinic acid and N- (2-hydroxypropyl) -2,
Condensate with 2,6,6-tetramethyl-4-hydroxypiperidine, tetrakis (2,2,6,6-tetramethyl-4-piperidyl), 1,2,3,4-butanetetracarboxylate, N , N &#0; -bis (2,2,6,6
-Tetramethyl-4-piperidyl) hexamethylenediamine and 1,2-dibromoethane polycondensate, bis (2,2,6,6-tetramethylpiperidyl) adipate, bis (2,2,6,6- Tetramethylpiperidyl)
Fumarate, poly [[6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4
-Diyl] [(2,2,6,6-tetramethyl-4-piperidyl) imino] hexamethylene [(2,2,6,6
-Tetramethyl-4-piperidyl) imino]], 2,4
-Di-t-butylphenyl-3,5-di-t-butyl-
4-hydroxybenzoate, 4-octylphenyl-
3,5-di-t-butyl-4-hydroxybenzoate, n-hexadecyl-3,5-di-t-butyl-4-
Examples thereof include hydroxybenzoate.

Examples of the antioxidant used in the present invention include phenol-based, phosphorus-based and sulfur-based antioxidants.
Here, as the phenolic antioxidant, 2,6-di-t
-Butyl-4-methylphenol, tris (3,5-di-t-
Butyl-4-hydroxybenzyl) isocyanurate, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, n-octadecyl-3- (3 ', 5'-di -t-butyl-4'-hydroxyphenyl) propionate, 4,4'butylidene bis- (3-methyl-6-t-butylphenol, triethylene glycol-bis [3- (3-t-butyl-4-hydroxy) -5-methylphenyl) propionate], 3,9-bis [2- [3 (3-t-butyl-4-humanroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4 8,10-Tetraoxaspiro [5,5]
For example, undecane.

Further, as phosphorus antioxidants, trisnonylphenyl phosphite, distearyl pentaerythritol diphosphite, tris (2,4-di-t-
Butylphenyl) phosphite, tetrakis (2,4-
Di-t-butylphenyl) -4,4'-biphenylene-
Di-phosphonite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-diphosphite, 2,2,- Examples thereof include methylenebis (4,6-di-t-butylphenyl) octyl phosphite. Examples of the sulfur-based antioxidant include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate,
Pentaerythritol tesrakis (3-lauryl thiopropionate) etc. can be mentioned.

The low-friction, high-dispersion synthetic resin composition of the present invention is black, and a colorant is used to add depth to this black. Colorants include dyes and pigments, and addition of pigments is particularly preferable. Specific examples of pigments include white pigments such as titanium oxide, zinc white, lead white, and lithobon, black pigments such as aniline black, iron black, and carbon black.
Yellow lead, yellow iron oxide, titanium yellow, Hansa yellow,
Yellow pigments such as benzine yellow and permanent yellow, orange pigments such as chrome vermillion, permanent orange and balkan first orange, brown pigments such as iron oxide, permanent brown and para brown, red iron oxide, cadmium red, antimony vermillion, permanent red and alizarin. Red pigments such as lake, thioindigo red, PV carmine, monolite fast red, purple pigments such as cobalt purple, manganese purple, fast violet, methyl violet lake, ultramarine blue, dark blue, cobalt blue, peacock blue lake, Victoria blue lake, Metal-free phthalocyanine blue, blue pigments such as indigo, chrome green, chrome oxide, emerald green, green gold, acid green lake,
In addition to green pigments such as malachite green lake and phthalocyanine green, metal powder pigments and the like can be mentioned.

The ultraviolet absorbers and ultraviolet absorbers used in the present invention include benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, benzoate compounds, oxazalide compounds, hindered amine compounds and nickel complex salts. Etc. Further, as the lubricant used in the present invention, talc, magnesium carbonate, calcium carbonate,
Kaolin is also included. Examples of the flame retardant used in the present invention include tetrabromobisphenol A derivatives,
Halogen-containing compounds such as hexabromodiphenyl ether and tetrabromophthalic anhydride: Triphenyl phosphate, triphenyl phosphite, phosphorus-containing compounds such as red phosphorus and ammonium polyphosphate: Nitrogen-containing compounds such as urea and guanidine: Silicon oil, organic Silicon-containing compounds such as silane and aluminum silicate:
Examples thereof include antimony compounds such as antimony trioxide and antimony phosphate. Further, examples of the other fillers used in the present invention include glass flakes, glass beads, silica, quartz, amorphous silicic acid, alumina, metal powder, calcium silicate, mica, wollastonite, and the like. The molding of the low-friction, high-dispersion synthetic resin composition of the present invention can be carried out by various procedures which are usually carried out. For example,
It can be carried out by forming it into a pellet and molding it with a processing machine such as an extruder, an injection molding machine or a roll mill.
It has also been found that it is better to set the mold temperature to a slightly lower temperature. Basically, the temperature in the range of the glass transition point or melting point of the synthetic resin is good. Further, it has been found that a mold having a good friction characteristic can be obtained when the mold is gradually cooled rather than rapidly cooled.

The embodiments of the present invention are summarized as follows. (1) A low-friction and high-dispersion synthetic resin composition in which RBC or CRBC fine powder is uniformly dispersed in a synthetic resin. (2) The low-friction / high-dispersion synthetic resin composition as described in 1 above, wherein the mass ratio of RBC or CRBC fine powder to synthetic resin is 5 to 90:95 to 10. (3) The synthetic resin is one or more resins selected from nylon 66, nylon 6, nylon 11, nylon 12, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polypropylene, polyethylene, polyphenylene sulfide, or 1 or 2 above. The low-friction, high-dispersion synthetic resin composition described in 2 above. (4) The average diameter of fine powder of RBC or CRBC is 30
The low-friction, high-dispersion synthetic resin composition as described in any one of 1 to 3 above, which is 0 μm or less. (5) The average diameter of fine powder of RBC or CRBC is 10
The low-friction, high-dispersion synthetic resin composition described in 4 above, which is ˜50 μm. (6) Any of the above 1 to 5 containing at least one additive selected from a stabilizer, an antioxidant, a colorant, an antistatic agent, an ultraviolet absorber, a lubricant, a flame retardant and other fillers. The low-friction, high-dispersion synthetic resin composition described in one. (7), 1 type or 2 types or more of a thermosetting resin of a group consisting of a phenol resin, a diaryl phthalate resin, an unsaturated polyester resin, an epoxy resin, a polyimide resin, and a triazine resin, and the whole composition. 20% by mass or less of the low friction and high dispersibility synthetic resin composition described in any one of 1 to 6 above. (8) RBC or CRBC fine powder and at least one additive selected from the group consisting of stabilizers, antioxidants, colorants, antistatic agents, ultraviolet absorbers, lubricants, flame retardants, and other fillers. Is mixed in advance, then the mixture is added to the synthetic resin at a temperature near the melting point of the synthetic resin, and the mixture is kneaded.

(Examples) The present invention will be described in more detail based on examples. Example 1 (Production of RBC fine powder) Degreased bran 7 obtained from rice bran
50g and liquid phenol resin (resole) 250g
Were mixed and kneaded while being heated to 50 ° C to 60 ° C. A homogeneous mixture with plasticity was obtained. The mixture was baked at 900 ° C. for 100 minutes in a nitrogen atmosphere using a rotary kiln, and the obtained carbonized product was further crushed using a crusher and then sieved with a 150 mesh screen to have an average particle size of 140 to 160 μm. An RBC fine powder was obtained. (Preparation of RBC fine powder and synthetic resin mixture) RB obtained
C fine powder 500g, nylon 66 powder 500g 240
The mixture was mixed and kneaded while being heated to 290 to 290 ° C. A homogeneous mixture with plasticity was obtained. The content of the RBC fine powder was 50% by mass. (Preparation of test piece) A homogeneous dispersible resin composition obtained by melt-mixing RBC fine powder and nylon 66 was injection molded to prepare a test piece.

Example 2 Using the same method as in Example 1, the average particle size was 140-16.
An RBC fine powder having a size of 0 μm was obtained. (Preparation of RBC fine powder and synthetic resin mixture) RB obtained
C fine powder 700g, nylon 66 powder 300g 240
The mixture was mixed and kneaded while being heated to 290 to 290 ° C. A homogeneous mixture with plasticity was obtained. The content of RBC fine powder was 70% by mass. (Preparation of test piece) A homogeneous dispersible resin composition obtained by melt-mixing RBC fine powder and nylon 66 was injection molded to prepare a test piece.

Example 3 (Production of RBC fine powder) Defatted bran 7 obtained from rice bran
50g and liquid phenol resin (resole) 250g
Were mixed and kneaded while being heated to 50 ° C to 60 ° C. A homogeneous mixture with plasticity was obtained. The mixture is heated to 1000 ° C in a nitrogen atmosphere using a rotary kiln.
The obtained carbonized product was further pulverized by using a pulverizer and then passed through a 400-mesh sieve to obtain RBC fine powder having an average particle size of 40 to 50 μm. (Preparation of RBC fine powder and synthetic resin mixture) RB obtained
C fine powder 700g, nylon 66 powder 300g 240
The mixture was mixed and kneaded while being heated to 290 to 290 ° C. A homogeneous mixture with plasticity was obtained. The content of RBC fine powder was 70% by mass. (Preparation of test piece) A homogeneous dispersible resin composition obtained by melt-mixing RBC fine powder and nylon 66 was injection molded to prepare a test piece.

Example 4 (Production of CRBC fine powder) 750 g of defatted bran obtained from rice bran and 250 g of liquid phenol resin (resole) were mixed and kneaded while heating at 50 ° C to 60 ° C. A homogeneous mixture with plasticity was obtained. The mixture was baked at 900 ° C. for 60 minutes in a nitrogen atmosphere using a rotary kiln. The obtained carbonized product was pulverized using a pulverizer and then sieved with a 200-mesh sieve to obtain RBC fine powder having an average particle size of 100 to 120 μm. 750 g of the obtained RBC fine powder and 500 g of solid phenol resin (resole) were added to 100
The mixture was mixed and kneaded while being heated to ℃ to 150 ℃. A homogeneous mixture with plasticity was obtained. Next, the plastic was pressure-molded at a pressure of 22 MPa into a spherical shape having a diameter of about 1 cm.
The mold temperature was 150 ° C. Take out the molded body from the mold, raise the temperature at a rate of 1 ° C / min up to 500 ° C in a nitrogen atmosphere, hold at 500 ° C for 60 minutes, and maintain at 900 ° C.
And sintered for about 120 minutes. Then 2-3 ° C up to 500 ° C
The temperature was lowered at a cooling rate of / min, and when the temperature was 500 ° C. or less, it was naturally cooled. The obtained CRBC molded product was crushed by using a crusher and then passed through a 500-mesh sieve to obtain CRBC fine powder having an average particle size of 20 to 30 μm. (Preparation of CRBC Fine Powder and Synthetic Resin Mixture) Obtained C
RBC fine powder 500g, nylon 66 powder 500g 2
The mixture was mixed and kneaded while being heated to 40 ° C to 290 ° C.
A homogeneous mixture with plasticity was obtained. The content of CRBC fine powder was 50% by mass. (Preparation of Test Specimen) A uniform dispersible resin composition obtained by melt-mixing CRBC fine powder and nylon 66 was injection molded to prepare a test specimen.

Examples 5-9 and Comparative Example 1 Same as Examples 1-4, RBC or CRBC fine powder, 2,6-di-t-butyl-4-methylphenol as antioxidant, malachite green lake as pigment A test piece was prepared under the conditions shown in Table 1 by adding a tetrabromobisphenol A derivative as a flame retardant. Further, a comparative test 1 was carried out by using a commercially available activated carbon fine powder (average particle diameter 30 μm) in place of the RBC or CRBC fine powder, and a comparative test 2 in which no RBC or CRBC fine powder or a commercially available activated carbon fine powder was added.

[0020]

[Table 1] Table 2 summarizes the characteristics of the low-friction, high-dispersion synthetic resin compositions obtained in Examples 1-9. The friction coefficient was measured with a torque type friction resistance measuring device (pin-on disc) using a steel ball having a diameter of 2 mm and a load of 50 g. In addition,
The sliding speed was 0.1 m / sec, and the measurement was performed in a dry state. The dispersibility was evaluated by visual inspection.

[0021]

[Table 2]

[0022]

As is clear from the results shown in Table 3, the low friction / high dispersibility synthetic resin composition of the present invention, which comprises the fine powder of RBC or CRBC and the synthetic resin, has excellent dispersibility of additives. Therefore, it was found that if the content of the fine powder of RBC or CRBC is increased, the composition is useful as a conductive resin composition.

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[Procedure amendment]

[Submission date] March 14, 2002 (2002.3.1)
4)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

Title: Low friction and highly dispersible synthetic resin composition containing fine powder of RBC or CRBC, and method for producing the same

Continued front page    F-term (reference) 4F070 AA13 AA15 AA42 AA47 AA54                       AA58 AC22 FA03 FB07                 4G146 AA01 AB01 AC02A AD22                       BA13 BA15 BA18 BA31 BC03                       BC23 BC33B                 4J002 BB021 BB111 CB001 CF051                       CL011 CL031 CN011 DM006                       FA096 FD016

Claims (7)

[Claims] 1. A low-friction / high-dispersion synthetic resin composition in which fine powder of RBC or CRBC is dispersed in a synthetic resin. 2. The low friction and high dispersive synthetic resin composition according to claim 1, wherein the mass ratio of RBC or CRBC fine powder to synthetic resin is 5 to 90:95 to 10. 3. The synthetic resin is one or more resins selected from nylon 66, nylon 6, nylon 11, nylon 12, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polypropylene, polyethylene and polyphenylene sulfide. The low-friction / high-dispersion synthetic resin composition according to claim 1 or 2. 4. The low-friction / high-dispersion synthetic resin composition according to claim 1, wherein the RBC or CRBC fine powder has an average diameter of 300 μm or less. 5. The low-friction friction according to claim 4, wherein the RBC or the fine powder of CRBC has an average diameter of 10 to 50 μm.
Highly dispersible synthetic resin composition. 6. A stabilizer, an antioxidant, a colorant, an antistatic agent, an ultraviolet absorber, a lubricant, a flame retardant, and at least one additive selected from other fillers.
A low-friction, high-dispersion synthetic resin composition according to claim 5. 7. A fine powder of RBC or CRBC, a stabilizer, an antioxidant, a coloring agent, an antistatic agent, an ultraviolet absorber,
After premixing at least one additive selected from the group consisting of lubricants, flame retardants, and other extender fillers, the mixture is added to the synthetic resin at a temperature near the melting point of the synthetic resin,
A method for producing a low-friction, high-dispersion synthetic resin composition to be kneaded.