JP3140133B2 - Composite material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a whisker reinforced composite material, and more particularly to a whisker reinforced composite material in which at least aluminum and niobium as impurities are Al ₂ O ₃ / Nb ₂ O ₅ ( (Molar ratio) is 0.6 or more, and relates to a composite material containing potassium hexatitanate whiskers having a tunnel structure and using a thermoplastic resin as a matrix.

[0002] Whiskers such as silicon carbide whiskers, silicon nitride whiskers, aluminum borate whiskers and potassium titanate whiskers are known as conventional reinforcing materials.
Only potassium titanate whiskers are widely used as reinforcements for general-purpose plastics and engineering rig plastics, because whiskers other than potassium titanate whiskers are too expensive. However, the price of potassium titanate whiskers is higher than the price of glass fiber and wollastonite, which are widely used as a reinforcing material for plastics, which greatly limits the use of composite materials containing potassium titanate whiskers. That is the fact. In order to expand the use of the composite material and further improve the position of potassium titanate whisker as a reinforcing material for plastics, it is necessary to develop an inexpensive potassium titanate whisker at least as expensive as glass fiber, or It is considered necessary to take drastic measures, such as developing potassium titanate whiskers having higher strength at the same production cost.

[0003] Among the above-mentioned viewpoints for obtaining inexpensive potassium titanate whisker reinforced plastics, there have been several inventions relating to the production of inexpensive potassium titanate whiskers (for example, JP-A-60-51).
615, published patent application No. 60-191019), but another viewpoint, that is, the development of a composite material having a low mechanical strength and a high mechanical strength by improving the strength of the whisker is particularly important. Not tried.

[0004] composite invention contain problems thus conventional potassium titanate whisker to be solved, in order potassium titanate whisker is costly,
The price of the plastics filled with the whiskers is inevitably set to be high, and therefore, there is a problem that the plastics are used only for very limited applications. Therefore, the development of a novel composite material that is inexpensive and has high strength has been desired.

An object of the present invention is to provide a composite material which is more inexpensive and has superior mechanical strength by improving the mechanical strength of potassium titanate whiskers.

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, the content of aluminum as an impurity and the content of niobium as a reinforcing material were reduced to Al ₂ O ₃ / Nb _2. O ₅ (molar ratio) was 0.6 or more, and it was found that it was effective to use a potassium hexatitanate whisker having a tunnel structure, thereby completing the present invention. That is, the conventional potassium titanate whisker is niobium derived from its production raw material,
Inevitably contains impurities such as phosphorus, aluminum, silicon, iron, and alkaline earth metals, so that only low-strength whiskers can be obtained. Furthermore, niobium and aluminum contained in potassium titanate whiskers Is adjusted so as to be 0.6 or more in terms of Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio), it is found that the strength of whiskers does not decrease even if impurities are contained. The present invention has been completed. That is, the conventional potassium titanate whisker is synthesized using anatase-type titanium oxide or metatitanic acid or naturally-occurring rutile sand or anatase sand by the sulfuric acid method containing a large amount of the above impurities including niobium as a raw material. However, potassium titanate whiskers synthesized from these raw materials inevitably contain many impurities, and the strength of plastics reinforced with the potassium titanate whiskers having a high impurity content is as strong as niobium contained in the whiskers. Aluminum content is A
The present invention was found to be inferior to the strength of plastics reinforced with potassium titanate whiskers adjusted with l ₂ O ₃ / Nb ₂ O ₅ (molar ratio) to 0.6 or more, and completed the present invention.

That is, according to the present invention, the content of aluminum as an impurity and the content of niobium are Al ₂ O ₃ as a reinforcing material.
/ Nb ₂ O ₅ (molar ratio) is 0.6 or more, and a potassium hexatitanate whisker having a tunnel structure is used.
It provides whisker reinforced plastics.
Hereinafter, the present invention will be described in detail. The potassium titanate whisker used in the present invention has a content of aluminum as an impurity and a content of niobium of Al ₂ O ₃ / Nb ₂ O _5.
Potassium hexatitanate whisker having a tunnel structure (molar ratio) of 0.6 or more, particularly preferably, the content of impurities other than aluminum and niobium in terms of oxide is 1% or less, and aluminum as an impurity Content and niobium content are Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio)
It is desirable that the whisker is a single crystal whisker having a tunnel structure of 0.6 or more and having no heterophase such as potassium titanate or titanium dioxide having a layered structure inside or on the surface of the whisker. That is, when the layered structure potassium titanate or titanium dioxide is contained in the whiskers, the strength of the whiskers themselves is lower than that of the single crystal whiskers, so that high strength potassium titanate whisker reinforced plastics cannot be obtained. Such a potassium titanate whisker is typically produced by the following method.

That is, the general formula K ₂ O.nTiO ₂ (where n =
A mixture of a titanium raw material compound and a potassium raw material compound blended at the ratios shown in 2-4) at 900-1100 ° C.
To produce massive potassium titanate whiskers, then immerse the massive product in water or warm water to separate the potassium titanate whiskers into single whiskers, and then add acid to the slurry to add pH. the by adjusting the 9.3 to 9.7, and the compositional conversion processing as the composition of the potassium titanate whisker is the composition of from 5.9 to 6.0 in TiO ₂ / K ₂ O (molar ratio), 900-1150 ° C
After heating for 1 hour or more, acid cleaning may be performed.

[0009] In the production of potassium titanate whiskers, as a titanium raw material compounds, hydrous titanium oxide, anatase titanium dioxide, it can be mentioned rutile titanium dioxide and rutile ore, K ₂ during firing as potassium starting compound Compounds that produce O, such as K ₂ O,
KOH, K ₂ CO ₃ and KNO ₃ can be exemplified. Almost all of the niobium contained in the raw material compound is dissolved in the crystal lattice of the potassium titanate whisker, whereas part of the aluminum in the raw material compound forms a compound with potassium, and thus part of the titanium is formed as titanium. Since it is only dissolved in the crystal lattice of the potassium whisker, the ratio of aluminum and niobium contained in the titanium raw material compound is at least 0.7 or more in terms of Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio). It is necessary. Aluminum which is not taken into the crystal structure of potassium titanate whisker and combines with potassium does not have any effect on the property improvement of potassium titanate whisker, but rather, the crystal structure of potassium titanate whisker is tunneled from the layered structure to the tunnel structure. In the process of converting into a structure, it reacts with the potassium titanate whisker and damages it, so it is desirable to separate and remove it. That is, after synthesizing the bulk potassium titanate whisker, the aluminum and potassium compounds are dissolved in water in the step of immersing the bulk material in water or warm water to separate it into a single whisker, so that the solid and liquid are added before the acid is added. It can be removed by separation. However, as long as the content of aluminum reacted with potassium is not more than about 0.2% in terms of oxide with respect to potassium titanate whiskers, there is no particular problem even if separation and removal are not performed. If the raw material compound contains a large amount of impurities that form a water-soluble compound with potassium, the lump is immersed in water or warm water and separated into single whiskers. Removal leads to an improvement in the properties of potassium titanate whiskers.

When the content of aluminum with respect to niobium is A
When a compound having a ratio of l ₂ O ₃ / Nb ₂ O ₅ (molar ratio) smaller than 0.7 is used as a raw material, an aluminum compound is added to the raw material compound and Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio) is used. ) May be adjusted to be 0.7 or more and 1.2 or less.
Even if Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio) is added so as to be more than 1.2, not only does the property of the synthesized potassium titanate whisker not be improved, but also the produced potassium aluminate It is not preferable because it is difficult to separate a lump into single whiskers because the amount of
The aluminum compound to be added includes aluminum sulfate, aluminum chloride, aluminum nitrate, aluminum hydroxide, aluminum oxide, aluminate and the like.

[0011] The total amount of niobium and aluminum is not particularly specified, as long as the molar ratio of both is within the above range. However, as can be seen from the above description, the total amount of the two depends on the amount of niobium contained in the raw material. Incidentally, when the amount of niobium contained in the raw materials usually used is large, it is about 0.6% in Nb ₂ O ₅ display, and in this case, the total amount of niobium and aluminum is about 0.9% in oxide display. Becomes

It is preferable that the content of impurities other than niobium and aluminum contained in potassium titanate is as small as possible, but there is no particular problem as long as it is 1% or less in terms of oxide. That is, when the content of these impurities exceeds 1%, the ratio of aluminum and niobium contained in the potassium titanate whiskers is 0.6 or more in terms of Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio). Also, since the mechanical strength of the potassium titanate whisker decreases, the strengthening effect of the potassium titanate whisker decreases. In particular, when an element having a valence other than tetravalent or an element having an ionic radius different from the ionic radius of Ti ⁴⁺ by 10% or more forms a solid solution in the crystal structure of the potassium titanate whisker, the potassium titanate whisker machine The rate at which the target strength decreases is large, which is not preferable. The shape of potassium titanate whisker is
The average length is 5 μm or more and the average aspect ratio (average length /
The average diameter is preferably 10 or more.

The thermoplastic resin used in the present invention includes general-purpose plastics such as polypropylene, ABS and vinyl chloride, polyamide, polyacetal, polyethylene terephthalate, polybutylene terephthalate, and the like.
Engineering plastics such as polyphenylene sulfide, polycarbonate, and liquid crystal polymer, or alloys thereof, and the like, and a commonly used thermoplastic resin can be used without any problem.

The mixing ratio of the potassium hexatitanate whisker and the plastics is 3 to 50% by weight of the potassium hexatitanate whisker. That is, when the mixing ratio of the potassium hexatitanate whisker is smaller than 3% by weight, the effect of strengthening the plastics by the potassium hexatitanate whisker is very small, and conversely, the mixing ratio of the potassium hexatitanate whisker is 50% by weight. In the range beyond
This is not preferable because not only the molding process becomes poor, but also the cost of the composite material increases.

In the production of the composite material according to the present invention, it is preferable to use a potassium titanate whisker which has been treated with a surface treating agent such as a silane coupling agent in terms of dispersibility. As a method of using the surface-treated potassium titanate whisker, there is a method of using a surface treatment agent which has been previously treated with a surface treatment agent, and a method of kneading the potassium titanate whisker and the plastics with a surface treatment agent. Is added, but using potassium titanate whiskers that have been previously treated with a surface treatment agent has a greater effect of the surface treatment agent.

Examples of the silane coupling agent usable in the present invention include amino-based silane coupling agents such as γ-aminopropyltriethoxysilane and N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane. Agents, epoxy silane coupling agents such as γ-glycidoxypropyl trimethoxysilane, β- (3,4 epoxycyclohexyl) ethyl trimethoxysilane, vinyl trimethoxy silane, vinyl triethoxy silane, vinyl Vinyl silane coupling agents such as tris (2-methoxyethoxy) silane, mercapto silane coupling agents such as γ-mercaptopropyl trimethoxysilane, and acrylic silane cups such as γ-methacryloxypropyl trimethoxysilane Ring agents can be used. The amount of the silane coupling agent added is
The content is preferably 2.0% by weight or less based on the potassium titanate whisker. That is, if the amount of the surface treatment agent exceeds this amount, such an effect is already saturated, and it is meaningless to add a large amount.

In the composite material of the present invention, one or two or more of various additives such as a flame retardant, a heat stabilizer and a lubricant may be added depending on the use and purpose of the composite material as long as the physical properties of the composite material are not adversely affected.
More than one species can be added. Further, other fillers can be mixed and used for the purpose of adding desired physical properties.
Since the potassium titanate whiskers used in the present invention have higher mechanical strength than conventional whiskers, it is only possible to improve the strength of plastics to a desired strength with a smaller amount of addition than before. Not
A composite material having a high mechanical strength, which cannot be achieved by the conventional potassium titanate whisker filling, can be obtained.

Hereinafter, the present invention will be described in more detail with reference to examples. The following examples are provided for illustrative purposes only, and are not intended to limit the scope of the invention.

Embodiment 1 TiO ₂ 30%, Nb ₂ O ₅ 0.129%, Al ₂ O ₃
4,700 g of metatitanic acid slurry containing 0.017%
18 ml of a 50 g / l aqueous solution of aluminum sulfate as Al ₂ O ₃ was added thereto, followed by stirring for 20 minutes.
Thereafter, 730 g of potassium carbonate powder was added and mixed, followed by spray drying under the conditions of an inlet temperature of 270 to 280 ° C and an outlet temperature of 80 to 85 ° C. Next, the powder was placed in an alumina crucible and heated in an electric furnace at a heating rate of 200 ° C./hour and a firing temperature of 940.
After calcination at a temperature of 1 ° C. and a holding time of 1 hour, the temperature was lowered at a rate of 150 ° C./hour.

The fired product was put into 12 liters of warm water in a stainless steel container and immersed for 5 hours. K. Use a homomixer (shear force mixer manufactured by Tokushu Kika Kogyo Co., Ltd.)
After stirring at 00 rpm for 1 hour, the slurry temperature was adjusted to 60 ° C. 5N-hydrochloric acid was added dropwise to adjust the pH to 9.4. If the stirring is further continued thereafter, potassium ions are eluted from between the layers of potassium tetratitanate, so that the pH becomes higher. Hydrochloric acid was added dropwise at 30 minute intervals to adjust the pH to 9.4. The whiskers were agglomerated by adding 0.2% by weight of a polymer coagulant (manufactured by Kyoritsu Organic Industrial Laboratories, trade name: Himoloc MP-173H) to the potassium titanate whiskers.

After filtration and washing, the mixture was calcined at 1000 ° C. for 1 hour. The fired product was put into 10 liters of warm water,
K. The fibers were dispersed by stirring with a homomixer for 30 minutes. The pH was adjusted to 4 by dropwise addition of 1N hydrochloric acid. After filtration, washing and drying, whiskers were obtained. When this whisker was identified by X-ray diffraction, only potassium hexatitanate was confirmed. Observation of the whiskers with a scanning electron microscope revealed that the average length was 14 μm and the average diameter was 0.4 μm. The specific surface area measured by the BET method was 4.4 m ² / g.

The potassium titanate whisker was analyzed by chemical analysis to find that 0.356% of Nb ₂ O ₅ and Al _{2
O 3 0.093%, Fe 2 O} 3 0.006%, MgO
0.008%, CaO 0.085%, ZnO 0.
012%, P ₂ O ₅ 0.008%, SiO ₂ 0.00
It includes impurity 6% such as, TiO ₂ / K ₂ O (molar ratio) was 6.0.

The (712) lattice spacing d was determined by the powder X-ray diffraction method using high-purity silicon powder (99.9%) as an internal standard and found to be 1.6645 Å.

20 parts of a sample obtained by treating the surface of the above potassium titanate whisker with 0.7% γ-aminopropyltrimethoxysilane and 80 parts of nylon 66 resin (trade name: UBE nylon 2020B, manufactured by Ube Industries, Ltd.) The mixture was melted and kneaded at a temperature of 280 ° C. with a mechanical twin-screw extruder AS-30 to form pellets.

Comparative Example 1 TiO ₂ 30%, Nb ₂ O ₅ 0.129%, Al ₂ O ₃
4,700 g of metatitanic acid slurry containing 0.017%
After 730 g of potassium carbonate powder was added and mixed therein, spray drying was performed under the conditions of an inlet temperature of 270 to 280 ° C and an outlet temperature of 80 to 85 ° C. Next, the powder was placed in an alumina crucible and heated in an electric furnace at a heating rate of 200 ° C./hour and a firing temperature of 940.
After calcination at a temperature of 1 ° C. and a holding time of 1 hour, the temperature was lowered at a rate of 150 ° C./hour.

The fired product was put into 12 liters of warm water in a stainless steel container and immersed for 5 hours. K. Use a homomixer (shear force mixer manufactured by Tokushu Kika Kogyo Co., Ltd.)
After stirring at 00 rpm for 1 hour, the slurry temperature was adjusted to 60 ° C. 5N-hydrochloric acid was added dropwise to adjust the pH to 9.4. If the stirring is further continued thereafter, potassium ions are eluted from between the layers of potassium tetratitanate, so that the pH becomes higher. Hydrochloric acid was added dropwise at 30 minute intervals to adjust the pH to 9.4. The whiskers were agglomerated by adding 0.2% by weight of a polymer coagulant (manufactured by Kyoritsu Organic Industrial Laboratories, trade name: Himoloc MP-173H) to the potassium titanate whiskers.

After filtration, the mixture was calcined at 1000 ° C. for 1 hour. The fired product was put into 10 liters of warm water, K. The whiskers were dispersed by stirring with a homomixer for 30 minutes.
The pH was adjusted to 4 by dropwise addition of 1N hydrochloric acid. After filtration, washing and drying, potassium hexatitanate whiskers were obtained. When the whiskers were observed with a scanning electron microscope,
The average length was 15 μm and the average diameter was 0.4 μm. When the specific surface area was measured by the BET method,
It was 5 m ² / g.

The potassium titanate whisker was analyzed by chemical analysis to find that 0.355% of Nb ₂ O ₅ and Al _{2
O 3 0.040%, Fe 2 O} 3 0.006%, MgO
0.009%, CaO 0.083%, ZnO 0.
012%, P ₂ O ₅ 0.009%, SiO ₂ 0.00
It includes impurity 6% such as, TiO ₂ / K ₂ O (molar ratio) was 6.0.

Further, the (712) lattice spacing d was determined by powder X-ray diffraction using high-purity silicon powder (99.9%) as an internal standard and found to be 1.6657 Å. The value was larger than that of potassium titanate. This is in the potassium titanate crystal lattice of Example 1, a small Al ³⁺ ionic radius is considered for substituted solid solution with Ti ³⁺ than Ti ^3+. 20 parts of a material obtained by treating the surface of the above potassium titanate whisker with 0.7% γ-aminopropyltrimethoxysilane and 80 parts of nylon 66 resin (trade name: UBE nylon 2020B, manufactured by Ube Industries, Ltd.) Screw extruder A
The mixture was melted and kneaded at 280 ° C. by S-30 to form pellets.

The pellets obtained in Example 1 and Comparative Example 1 were dried at 120 ° C. for 12 hours using a vacuum dryer, and then subjected to cylinder temperature control using a SAV-30-30 type injection molding machine manufactured by Yamashiro Seiki Seisaku-sho, Ltd. Injection molding was performed at 260 to 280 ° C and a mold temperature of 80 ° C to obtain a test piece for measuring tensile strength and bending strength. Table 1 shows the results of measuring the strength when absolutely dry.

Table 1 Example 1 Comparative Example 1 Tensile strength (kgf / cm ² ) 1210 1020 Flexural strength (kgf / cm ² ) 2190 1750 Flexural modulus (kgf / cm ² ) 94000 80500 Potassium titanate whisker Was extracted, and the average length was measured. As a result, it was 7.3 μm in Example 1 and 7.5 μm in Comparative Example 1, and there was no particular difference in the length of the potassium titanate whiskers in both test pieces. .

Embodiment 2 FIG. In Example 1, the sintering temperature after removing part of potassium from between the layers of the potassium tetratitanate whisker was set to 10
A potassium hexatitanate whisker was synthesized under the same conditions except that the temperature was changed from 00 ° C to 950 ° C. The purity and composition of the obtained potassium titanate whisker were determined in Example 1.
Was the same as

20 parts of a sample obtained by treating the surface of the above potassium titanate whisker with 0.6% γ-glycidoxypropyltrimethoxysilane and 80 parts of a polyacetal resin (manufactured by Polyplastics, trade name: DURACON M90) were mixed with: 220 with a twin screw extruder AS-30 made by Nakatanani Machinery
The mixture was melted and kneaded at a temperature of ° C to form pellets.

Comparative Example 2 Anatase type titanium oxide (Nb ₂ O ₅
0.157%, 0.032% of Al ₂ O ₃ ) were used, and a tunnel structure / potassium hexatitanate whisker was synthesized under the same conditions as in Comparative Example 1. When the whiskers were observed with a scanning electron microscope, the average length was 15 μm.
m, and the average diameter was 0.4 μm. When the potassium whisker was examined by chemical analysis, it was found that Nb
₂ O ₅ 0.131%, Al ₂ O ₃ 0.026%, Fe ₂ O ₃
0.012%, MgO 0.014%, CaO 0.
094%, ZnO 0.014%, P ₂ O ₅ 0.010
%, Impurities such as 0.012% of SiO ₂ and TiO ₂
/ K ₂ O (molar ratio) was 6.0.

20 parts of a sample obtained by treating the surface of the above potassium titanate whisker with 0.6% γ-glycidoxypropyltrimethoxysilane and 80 parts of a polyacetal resin (manufactured by Polyplastics, trade name: Duracon M90) were mixed with Nakatanani. 220 ° C by machine twin screw extruder AS-30
And melted and kneaded at the above temperature to obtain pellets.

The pellets obtained in Example 2 and Comparative Example 2 were dried at 110 ° C. for 10 hours using a vacuum dryer, and then subjected to a cylinder temperature control using a SAV-30-30 type injection molding machine manufactured by Yamashiro Seiki Seisaku-sho, Ltd. 210 ° C, mold temperature 80 ° C
Injection molding was performed under the following conditions to obtain a test piece for measuring tensile strength and bending strength. Table 2 shows the strength measurement results. When potassium titanate whiskers were extracted from the test piece and their lengths were measured, no particular difference was found between the lengths of both potassium titanate whiskers.

Table 2 Example 2 Comparative Example 2 Tensile strength (kgf / cm ² ) 1210 960 Flexural strength (kgf / cm ² ) 2020 1630 Flexural modulus (kgf / cm ² ) 102000 78500 Example 3 Anatase type titanium oxide (Nb ₂ O ₅
0.157%, 0.072% of Al ₂ O ₃ ) was used, and a tunnel structure / potassium hexatitanate whisker was synthesized under the same conditions as in Example 1. When the whiskers were observed with a scanning electron microscope, the average length was 15 μm.
m, and the average diameter was 0.4 μm. When the potassium whisker was examined by chemical analysis, it was found that Nb
0.130% ₂ O ₅ , 0.055% Al ₂ O ₃ , Fe ₂ O ₃
0.008%, MgO 0.009%, CaO 0.
101%, ZnO 0.010%, P ₂ O ₅ 0.010
%, Including impurities SiO ₂ 0.007% such as, TiO ₂
/ K ₂ O (molar ratio) was 6.0.

15 parts of a sample obtained by treating the surface of the above potassium titanate whisker with 0.6% γ-glycidoxypropyltrimethoxysilane and 85 parts of a polycarbonate resin (trade name: Iupilon S-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd.) By a twin screw extruder AS-30 manufactured by Nakatani Machinery Co., Ltd.
C. and melted and kneaded to obtain pellets.

Comparative Example 3 The potassium titanate whisker (γ) used in Comparative Example 2
15 parts of glycidoxypropyltrimethoxysilane treated with 0.6%) and 85 parts of a polycarbonate resin (trade name: Iupilon S-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd.) were subjected to 280 by a twin screw extruder AS-30 manufactured by Nakatanani Machinery. C. and melted and kneaded to obtain pellets.

The pellets obtained in Example 3 and Comparative Example 3 were injection-molded using a SAV-30-30 injection molding machine manufactured by Yamashiro Seiki Seisakusho under conditions of a cylinder temperature of 290 ° C. and a mold temperature of 90 ° C. to obtain a tensile strength. And the test piece for bending strength measurement was obtained. Table 3 shows the strength measurement results. In addition, when the potassium titanate whisker was extracted from the test piece and its length was measured, no particular difference was recognized in the length of both potassium titanate whiskers.

Table 3 Example 3 Comparative Example 3 Tensile strength (kgf / cm ² ) 920 750 Flexural strength (kgf / cm ² ) 1630 1310 Flexural modulus (kgf / cm ² ) 82500 67000 Example 4 Example 1 20 parts of a sample obtained by treating the surface of the obtained potassium hexatitanate whisker with 0.5% of γ-glycidoxypropyltrimethoxysilane and 80 parts of a polybutylene terephthalate resin (manufactured by Polyplastics, trade name: Duranex 2000) And a twin screw extruder A made by Nakatani Machinery
According to S-30, the mixture was melted and kneaded at 250 ° C. to obtain pellets.

Comparative Example 4 20 parts of a sample obtained by treating the surface of the potassium hexatitanate whisker obtained in Comparative Example 1 with 0.5% of γ-glycidoxypropyltrimethoxysilane and a polybutylene terephthalate resin (manufactured by Polyplastics) (Trade name: JURANEX 2000) 80 parts and a twin screw extruder A manufactured by Nakatani Machinery Co., Ltd.
According to S-30, the mixture was melted and kneaded at 250 ° C. to obtain pellets.

The pellets obtained in Example 4 and Comparative Example 4 were injection-molded using a SAV-30-30 injection molding machine manufactured by Yamashiro Seiki Seisakusho under conditions of a cylinder temperature of 250 ° C. and a mold temperature of 70 ° C. And the test piece for bending strength measurement was obtained. Table 4 shows the strength measurement results. In addition, when the potassium titanate whisker was extracted from the test piece and its length was measured, no particular difference was recognized in the length of both potassium titanate whiskers.

Table 4 Example 4 Comparative Example 4 Tensile Strength (kgf / cm ² ) 1030 820 Flexural Strength (kgf / cm ² ) 1980 1510 Flexural Modulus (kgf / cm ² ) 106500 78500 Example 5 Example 1 The obtained potassium hexatitanate whisker 7
A part and a polypropylene resin (manufactured by Ube Industries, trade name: UBE Polypro J709HK) 93 parts were melted and kneaded at 220 ° C. by a twin screw extruder AS-30 manufactured by Nakatani Machine to obtain pellets.

Comparative Example 5 The potassium hexatitanate whisker 7 obtained in Comparative Example 1
And polypropylene resin (Ube Industries, trade name: UBE)
93 parts of Polypropylene J709HK) were melted and kneaded at 220 ° C. with a twin screw extruder AS-30 manufactured by Nakatani Machinery to obtain pellets.

The pellets obtained in Example 5 and Comparative Example 5 were injection-molded using a SAV-30-30 injection molding machine manufactured by Yamashiro Seiki Seisakusho under conditions of a cylinder temperature of 220 ° C. and a mold temperature of 60 ° C. And the test piece for bending strength measurement was obtained. Table 5 shows the strength measurement results. In addition, when the potassium titanate whisker was extracted from the test piece and its length was measured, no particular difference was recognized in the length of both potassium titanate whiskers.

Table 5 Example 5 Comparative Example 5 Tensile strength (kgf / cm ² ) 410 310 Flexural strength (kgf / cm ² ) 470 390 Flexural modulus (kgf / cm ² ) 24000 17000

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-51615 (JP, A) JP-A-60-259627 (JP, A) JP-A-1-301516 (JP, A) JP-A-2- 221460 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C30B 1/00-35/00 C08K 3/22 C08K 7/04 C08L 101/00

Claims (2)

(57) [Claims] 1. The content of aluminum as an impurity and the content of niobium in Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio) are 0.1 to 0.1.
A composite material containing a potassium hexatitanate whisker of 6 or more and 1.1 or less and a thermoplastic resin. 2. The content of aluminum as an impurity and the content of niobium in an Al ₂ O ₃ / Nb ₂ O ₅ (molar ratio) of 0.
A composite material comprising a potassium hexatitanate whisker having a content of 6% or more and an impurity other than aluminum and niobium of 1% or less and a thermoplastic resin.