JPS5925823B2 - polyamide composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is characterized in that the appearance and
This invention relates to a polyamide composition with excellent properties such as strength, rigidity, hardness, creep properties, dimensional stability, thermal properties, heat resistance, weather resistance, and moldability.

Mechanical, thermal and chemical properties of polyamides, e.g.
In order to improve rigidity, strength, dimensional stability, heat distortion temperature, etc., it is possible to add inorganic fillers to polyamide.

However, simply mixing an inorganic filler into a polyamide has drawbacks such as a marked decrease in bending strength, elongation, impact strength, etc. of the molded product of the resulting polyamide composition.

In particular, in the case of molded products made by injection molding, flow marks and jet marks caused by inorganic fillers appear on the surface, making it difficult to obtain a homogeneous and beautiful appearance, resulting in an extremely low commercial value. Conventionally, in order to improve the decrease in mechanical strength, inorganic fillers are treated with organic silanes, surfactants, chromium compounds, polymer solutions, Radex, etc. to improve wetting and reactivity between the inorganic fillers and resin. A method is being taken. Furthermore, a method of coating the surface of an inorganic filler with a reactive organic acid, as disclosed in Japanese Patent Application Laid-Open No. 49-1656, has also been invented by some of the present inventors. Although such methods have yielded somewhat satisfactory results in terms of mechanical strength, results that are excellent in both appearance and mechanical strength have not been obtained. As a result of intensive studies aimed at improving these drawbacks, the present inventor discovered that a polyamide composition having excellent appearance and mechanical strength could be obtained by treating an inorganic filler with a specific method, and the present invention. reached.

That is, the present invention provides a treated filler obtained by mixing (1) polyamide, (2) 0.1 to 10% by weight of a specific organic carboxylic acid based on the inorganic filler, and (3) the It consists of a silane compound having one or more amino groups, epoxy groups or ethylenically unsaturated groups and 2 to 3 alkoxysilyl groups in the molecule in an amount of 0.1 to 10% by weight based on the treated filler,
A polyamide composition characterized in that the amount of inorganic filler in the composition is 5 to 75% by weight. The polyamide composition of the present invention has excellent appearance and mechanical, thermal, and chemical properties such as tensile and bending strength, elastic modulus, impact strength, heat distortion temperature, hardness, dimensional stability, and creep properties. These values are significantly improved compared to when only polyamide was used.

In the present invention, the polyamides used are aliphatic polyamides and aromatic polyamides, with the former being particularly preferred.

For example, nylon 6, nylon 66, nylon 610
, nylon 612, nylon 11, nylon 12, etc., and aromatic polyamides include, for example,
Examples include polyhexamethylene diamine terephthalamide, polyhexamethylene diamine isophthalamide, and the like. It is also possible to use mixtures or copolymers of two or more types, including aliphatic and aromatic. Preferred are nylon 6 and nylon 66. As the inorganic filler used in the present invention, those well known as fillers for rubber and plastics are used.

As long as it is solid, the shape is not limited and can take the form of powder, fibrous powder, fibers, whiskers, balloons, etc., but from economical considerations, fine powder is preferred. Specifically, for example, clay, fired resin, talc, catalbo, silica,
Alumina, magnesium oxide, calcium silicate, asbestos, sodium aluminate, calcium aluminate, magnesium aluminosilicate, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, barium sulfate,
Potassium alum, sodium alum, iron alum, shirasu balloon, glass balloon, carbon black, coke please, iron oxide, zinc oxide, antimony trioxide, boric acid, borax, zinc borate, metal powder, metal whiskers, mica, graphite, titanium oxide, carbon fiber, glass fiber,
Examples include glass fiber powder, glass beads, calcium carbonate, zinc carbonate, hydrotalcite, and the like. Particularly preferred are basic inorganic fillers. Organic carboxylic acids used in the present invention (excluding aromatic carboxylic acid esters)
As such, acrylic acid, methacrylic acid, fumaric acid, and maleic acid are effective in the present invention. These acids may be used alone or as a mixture of two or more. Alternatively, an acid anhydride may be used as an acid precursor and converted into an acid during the reaction. The amount of acid used is 0.1 to 10 parts by weight, preferably 0.3 to 10 parts by weight, per 100 parts by weight of the inorganic filler.
5 parts by weight.

If the amount used is less than the above range, sufficient effects will not be obtained on both the appearance and mechanical strength of the molded product, and conversely, if it exceeds the above range, the improvement in mechanical strength will be saturated and the appearance of the molded product will deteriorate. On the contrary, it becomes defective. When heating and mixing an inorganic filler and an organic carboxylic acid, it is also effective to use a solvent to improve contact between each compound.

Examples of these solvents include water, alcohol, acetone, etc., and mixed solvents thereof. Further, when the inorganic filler and the acid are reacted by heating and mixing, it is preferable to carry out the heating reaction under conditions such that water is removed from the system. The heating temperature is
It is selected depending on the type and reactivity of the acid, but 20 to 25
The temperature is 0°C, preferably 50-200°C. For the purpose of preventing side reactions and the like, it is preferable to heat and mix (react) in an atmosphere of an inert gas such as nitrogen gas. A silane compound having one or more amino groups, epoxy groups, or ethylenically unsaturated groups and 2 to 3 alkoxysilyl groups in the molecule is mixed with the treated inorganic filler thus obtained.

For example, γ-aminopropyltriethoxysilane, γ
-aminopropyltrimethoxysilane, Nβ(aminoethyl)-γ-aminopropyltrimethoxysilane, N-
β(aminoethyl)-γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-
Ureidopropyltrimethoxysilane, β-(3,4 epoxycyclohexyl)ethyltrimethoxysilane, β
- (3,4 epoxycyclohexylethyltriethoxysilane, γ-glycidoxylpropyltrimethoxysilane, γ-glycidoxylpropyltriethoxysilane,
Vinyl-tris(β-methoxyethoxy)silane, γ-
Examples include methacryloxypropyltrimethoxysilane, vinyltrichlorosilane, and a combination of two or more thereof. The amount of the compound having one or more amino groups, epoxy groups, or ethylenically unsaturated groups and 2 to 3 alkoxysilyl groups in the molecule is 0.1 to 10 parts by weight per 100 parts by weight of the treated inorganic filler. parts, preferably 3 to 5 parts by weight of O.

If the amount used is less than the above range, sufficient effects will not be obtained on both the appearance and mechanical strength of the molded product, or conversely,
If the weight part is exceeded, the improvement in mechanical strength is saturated;
The appearance of molded products tends to deteriorate. The amount of organic carboxylic acid (A) to be used, one or more amino groups or epoxy groups or ethylenically unsaturated groups in the molecule and two
Silane compound (B) having ~3 alkoxysilyl groups
The relative ratio (A/B) to the amount used is 0.1 to 101, preferably 0.2 to 4.

Although mechanical strength can be improved by treating an inorganic filler with a silane compound or an organic carboxylic acid alone, the effect of improving the appearance of the molded product is small.

Mechanical strength and molded product appearance are synergistically improved only by using both at the same time.

How to use silane compounds! Although it may be mixed into the ζ polyamide pellets or powder, it should preferably be mixed into the organic carboxylic acid treated inorganic filler. When treating the treated inorganic filler with a silane compound, it is also effective to use a solvent to improve contact between each compound.

Examples of these solvents include solvents such as water and alcohol, and mixed solvents thereof. Further, it is preferable to thoroughly mix the treated inorganic filler and the silane compound and then heat the mixture to react. The heating temperature is selected depending on the type and reactivity of the silane compound, but is preferably 20 to 200°C, preferably 50°C.
The temperature is ~180°C. For the purpose of preventing side reactions, it is preferable to heat and mix in an atmosphere of an inert gas such as nitrogen gas. The amount of the thus obtained treated inorganic filler used in the polyamide composition is 5 to 75% by weight, preferably 10 to 75% by weight.
It is 65% by weight.

If the amount used is less than 5% by weight, the mechanical, thermal and chemical properties of the polyamide composition will not be improved as expected. Moreover, when it exceeds 75% by weight, the properties of the polyamide composition become brittle, furthermore, the moldability decreases, and the commercial value decreases, which is not preferable. The composition of the present invention may contain auxiliary agents such as a heat stabilizer, a weather resistance improver, an antistatic shelving agent, a lubricant, and a coloring agent in addition to the above-mentioned components.

The composition of the present invention can be produced by melt-kneading using a general melt-kneading machine such as a single-screw extruder, a twin-screw extruder, or a Panbury mixer. Similarly to conventional polyamide compositions, the composition of the present invention can be made into molded articles, tubes, rods, films, sheets, filaments, etc. by conventional methods such as injection molding, extrusion molding, and compression molding. It can be made into molded products of various shapes. Particularly effective for injection molding. Next, the present invention will be described with reference to examples, which are merely illustrative and do not limit the present invention in any way.Example 1: 1.5 parts by weight of maleic anhydride was added to 100 parts by weight of magnesium hydroxide. , 140'C in a pen shell mixer.
After heating and mixing for 20 minutes and thoroughly drying, 1.0 part by weight of γ-aminopropyltriethoxysilane was added,
After heating and mixing at 130° C. for 10 minutes, the mixture was thoroughly dried.

100 parts by weight of the obtained treated magnesium hydroxide and 150 parts by weight of nylon 6 chips were added at a cylinder temperature of 23.
The mixture was kneaded and extruded using an extruder with a diameter of 65 mm and a temperature of 0°C to 280°C.

A test piece was molded from the obtained chip using an in-line screw type injection molding machine. Table 1 shows the physical properties of the test piece.
Comparative Example 1 Table 1 shows the physical properties of a test piece obtained by kneading, extruding, and molding 100 parts by weight of sufficiently dried untreated magnesium hydroxide and 150 parts by weight of nylon 6 chips in the same manner as in Example 1.

Comparative Example 2 100 parts by weight of magnesium hydroxide and 1.5 parts by weight of maleic anhydride were heated and mixed in a pen shell mixer at 140° C. for 20 minutes, and then thoroughly dried.

Table 1 shows the physical properties of a test piece obtained by kneading, extruding, and molding the treated magnesium hydroxide and 150 parts by weight of nylon 6 chips in the same manner as in Example 1. Comparative Example 3 1.0 parts by weight of γ-aminopropyltrienoxydisilane was mixed with 100 parts by weight of magnesium hydroxide at 130° C. for 10 minutes in a pen shell mixer, and then thoroughly dried.

Table 1 shows the physical properties of a test piece obtained by kneading, extruding, and molding the treated magnesium hydroxide and 150 parts by weight of nylon 6 chips in the same manner as in Example 1.

Comparative Example 4 A test piece was molded using the nylon 6 chips used in Example 1 using an in-line screw injection molding machine.

The physical properties are shown in Table 1. However, the bending properties indicate the yield value. Example 2 1 part of acrylic acid per 100 parts of magnesium hydroxide
．． 5 parts by weight at 140°C in a pen shell mixer.
After heating and mixing for 0 minutes and thoroughly drying, 1.2 parts by weight of γ-aminopropyltriethoxysilane was added, and 13
After heating and mixing at 0° C. for 10 minutes, the mixture was thoroughly dried.

100 parts by weight of the obtained treated magnesium hydroxide and 150 parts by weight of nylon 66 chips were added at a cylinder temperature of 270%.
The mixture was kneaded and extruded using an extruder with a diameter of 65 mm at ~320°C.

A test piece was made from the obtained chip using an in-line screw type injection molding machine. Table 2 shows the physical properties of the test piece.
Comparative Example 5 Table 2 shows the physical properties of a test piece obtained by kneading, extruding, and molding 100 parts by weight of sufficiently dried untreated magnesium hydroxide and 150 parts by weight of nylon 66 chips in the same manner as in Example 2.

Comparative Example 6 100 parts by weight of magnesium hydroxide and 1.5 parts by weight of acrylic acid were heated and mixed in a pen shell mixer at 140'C for 20 minutes, and then thoroughly dried.

The obtained treated magnesium hydroxide and 150 parts by weight of nylon 66 chips were kneaded, extruded and molded in the same manner as in Example 2, and the physical properties of the test piece obtained are shown in Table 2. Comparative Example 7 1.0 parts by weight of γ=aminopropyltriethoxysilane was mixed with 100 parts by weight of magnesium hydroxide at 130° C. for 10 minutes in a pen shell mixer, and then thoroughly dried.

The obtained treated magnesium hydroxide and 150 parts by weight of nylon 66 chips were kneaded, extruded and molded in the same manner as in Example 1, and the physical properties of the test piece obtained are shown in Table 2.

Comparative Example 8 A test piece was molded using the nylon 66 chip used in Example 2 using an in-line screw type injection molding machine.

The physical properties are shown in Table 1. However, the bending properties indicate the yield value. Example 3 1.0 parts by weight of methacrylic acid per 100 parts by weight of calcium silicate.
5 parts by weight at 140°C in a pen shell mixer.
After heating and mixing for 0 minutes and thoroughly drying, 1.0 parts by weight of γ-glycidoxylpropyltrimethoxysilane was further added, and after heating and mixing at 130° C. for 10 minutes, the mixture was thoroughly dried.

100 parts by weight of the obtained treated calcium silicate and nylon 6
150 parts by weight of 6 chips at a cylinder temperature of 270~
The mixture was kneaded and extruded using an extruder with a diameter of 65 mm at 320°C. A test piece was made from the obtained chip using an in-line screw type injection molding machine. Table 3 shows the physical properties of the test piece. Comparative Example 9 Table 2 shows the physical properties of a test piece obtained by kneading and extruding 100 parts by weight of sufficiently dried untreated calcium silicate and 150 parts by weight of nylon 66 chips in the same manner as in Example 3.

Comparative Example 10 100 parts by weight of calcium silicate, 1 part of methacrylic acid
．． 5 parts by weight were heated and mixed in a pen shell mixer at 140° C. for 20 minutes, and then thoroughly dried.

Table 3 shows the physical properties of a test piece obtained by kneading, extruding, and molding the obtained treated calcium silicate and 150 parts by weight of nylon 66 chips in the same manner as in Example 3.

Comparative Example 11 1.0 parts by weight of γ-glycidoxylpyltriethoxysilane was mixed with 100 parts by weight of calcium silicate in a pen shell mixer at 130° C. for 10 minutes, and then thoroughly dried.

The obtained treated calcium silicate and nylon 66 chips 15
Table 3 shows the physical properties of a test piece obtained by kneading, extruding, and molding 0 parts by weight in the same manner as in Example 1.

Example 4 1.2 parts by weight of fumaric acid was added to 100 parts by weight of calcium silicate at 140°C in a pen shell mixer.
After mixing for 20 minutes and thoroughly drying, add 1 part by weight of r-glycidoxylpropyltrimethoxysilane,
After heating and mixing at 30° C. for 10 minutes, the mixture was thoroughly dried.

100 parts by weight of the obtained treated calcium silicate and nylon 6
6 chips 150 parts by weight, cylinder temperature 270~3
The mixture was kneaded and extruded using an extruder with a diameter of 65 mm at 15°C. A first test piece was prepared from the obtained chip using an in-line screw type injection molding machine. The results are shown in Table 4. Comparative Example 12 100 parts by weight of calcium silicate, 1 part by weight of methacrylic acid
．． 5 parts by weight were heated and mixed in a pen shell mixer at 140° C. for 20 minutes, and then thoroughly dried.

Claims (1)

[Claims] 1. At least one organic carboxylic acid selected from acrylic acid, methacrylic acid, fumaric acid, and maleic acid is mixed in an amount of 0.1 to 10% by weight based on the polyamide and inorganic filler. The obtained treated filler and a silane having one or more amino groups, epoxy groups or ethylenically unsaturated groups and 2 to 3 alkoxysilyl groups in the molecule in an amount of 0.1 to 10% by weight based on the treated filler. A polyamide composition characterized in that the amount of inorganic filler in the polyamide composition is 5 to 75% by weight.