JPH06287378A - Reinforced thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the title composition which can give a molding excellent in mechanical strengths, rigidity and heat distortion resistance especially warpage resistance and appearance. CONSTITUTION:The composition is prepared by mixing a resin composition comprising 20-50wt.% copolyamide comprising 75-93wt.% epsilon-aminocaproic acid part and 7-25wt.% adipic acid/hexamethylenediammonium salt part and 50-80wt.% polypropylene modified with an unsaturated acid with glass fibers in a weight ratio of 90:10-50:50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention provides a resin composition comprising a specific polyamide resin and an unsaturated acid-modified polypropylene with glass fiber to obtain mechanical strength,
The present invention relates to a thermoplastic reinforced resin composition which is excellent in rigidity and heat distortion resistance, and in particular, can be obtained as a molded product excellent in warp deformation prevention property and appearance.

[0002]

2. Description of the Related Art Generally, since crystalline polypropylene is relatively inexpensive and has excellent mechanical strength, it is used for the production of various molded products such as injection molded products, hollow molded products, films, sheets and fibers. There is. However, mechanical properties may not be sufficient depending on various specific uses, and there is a problem that expansion of the specific uses is limited. Especially regarding rigidity and heat distortion resistance,
Since it is inferior to polyesters such as polystyrene, ABS resin, polyethylene terephthalate and polybutylene terephthalate, there is a drawback that the use of crystalline polypropylene is limited. Therefore, conventionally, the mechanical strength of the crystalline polypropylene, rigidity, various fillers to improve heat distortion resistance, for example, glass fiber, carbon fiber, whiskers, fibrous fillers such as metal fibers, mica, talc, Plate-like fillers such as kaolinite and granular fillers such as calcium carbonate, diatomaceous earth, alumina and glass beads are used.

Among these fillers, the fibrous filler is
Particularly strong in reinforcing effect compared to fillers of other shapes, glass fiber is relatively inexpensive in price and excellent in cost performance as a reinforcing material, so it requires mechanical strength, rigidity and heat distortion resistance. In such a field, a thermoplastic reinforced resin composition in which glass fiber is mixed with crystalline polypropylene is widely used. However, a molded article using such a thermoplastic reinforced resin composition has a large warp deformation, the surface of the molded article is rough, and an appearance defect such as a decrease in surface gloss occurs. There was a great limitation in the use of it for exterior parts.

Further, in order to improve mechanical strength, rigidity and heat distortion resistance, a resin composition obtained by compatibilizing a polyamide resin and a polyolefin resin with a compatibilizing agent such as unsaturated acid-modified polyolefin is used for glass. A method of filling an inorganic filler such as fiber is also known. However, the molded product obtained by this method also has not been able to improve the warp deformability and the appearance, and has been considerably limited in applications requiring dimensional accuracy and use in external parts.

As a method for suppressing warp deformation, EPDM
An example in which a rubber component such as the above is added to crystalline polypropylene has been disclosed (JP-A-52-8052). However, when a rubber component is added to crystalline polypropylene, properties such as mechanical strength, rigidity, and heat distortion resistance are significantly deteriorated.

Further, Japanese Patent Publication No. 64-11218 discloses an attempt to use a plate-like filler such as mica and a fibrous filler such as glass fiber in combination.
It provides a material with high rigidity and excellent warp deformability. However, these materials have significantly deteriorated weld strength and appearance, and their applications have been greatly limited.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is excellent in mechanical strength, rigidity and heat distortion resistance, particularly in molding which is excellent in warp deformation prevention property and appearance. An object of the present invention is to provide a thermoplastic reinforced resin composition from which a product can be obtained.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a resin composition obtained by mixing a specific copolymerized polyamide and a specific modified polypropylene in a specific amount is filled with a specific amount of glass fiber. As a result, they have found that the above problems can be solved all at once, and have reached the present invention. That is, the present invention comprises: 1) 75-93% by weight of ε-aminocaproic acid portion and 7-25% by weight of hexamethylene diammonium adipic acid salt portion.
The glass fiber has a weight ratio of 9 to a resin composition composed of 20 to 50% by weight of a copolyamide and 50 to 80% by weight of a modified polypropylene modified with an unsaturated acid.
A thermoplastic reinforced resin composition blended in a ratio of 0:10 to 50:50. 2) An injection molded product using the thermoplastic reinforced resin composition of 1). Is.

Explaining the contents of the present invention in detail, the modified polypropylene used in the present invention may be modified polypropylene alone or a mixture of modified polypropylene and unmodified crystalline polypropylene. The modified polypropylene is obtained by melt-kneading the crystalline polypropylene and the unsaturated acid in the presence of the radical generator.

The crystalline polypropylene used as a raw material for the modified polypropylene is not particularly limited, but a normal polypropylene homopolymer, a propylene ethylene block copolymer, a propylene ethylene random copolymer and the like are preferable. Examples of unsaturated acids include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, maleic anhydride, itaconic anhydride, and the like.

The content of unsaturated acid grafted on the modified polypropylene is preferably 0.01% by weight or more.
If it is less than 0.01% by weight, the compatibility between the modified polypropylene and the copolyamide becomes poor and the mechanical strength decreases. When the modified polypropylene and the unmodified crystalline polypropylene are mixed and used, it is preferable that the unsaturated acid is contained in an amount of 0.01% by weight or more in the total polypropylene.

Various known methods can be used for melt-mixing the crystalline polypropylene and the unsaturated acid. The above-mentioned unsaturated acid and di-t-butylperm are added to the crystalline polypropylene powder. Organic peroxides such as oxide, dicumyl peroxide, and benzoyl peroxide are added, and the mixture is stirred and mixed with a Henschel mixer (trade name) or the like, and then melt-kneading temperature of 160 ° C to 3 using an extruder.
The method of melt-kneading and extruding at 00 ° C., preferably 180 ° C. to 250 ° C. is simple and is preferably used.

In addition, the modified polypropylene usually contains additives such as antioxidants, heat stabilizers, ultraviolet absorbers, higher fatty acid metal salts, and the like, which are added to crystalline polypropylene.
Lubricants, pigments, inorganic fillers and the like can be used in combination.

The copolymerized polyamide used in the present invention is
It is a copolymer obtained by mixing ε-aminocaproic acid and hexamethylene diammonium adipic acid salt and subjecting them to heat condensation, or by mixing each polymer and heating and melting it to obtain an amide exchange reaction. The content of ε-aminocaproic acid in the copolymer is 75 to 93% by weight. If it is less than 7% by weight, the resulting molded article cannot be sufficiently warped and deformed, and if the copolymerized polyamide exceeds 25% by weight, not only the industrial productivity is lowered but also It is not preferable because the use of the copolyamide decreases the effect of improving the physical properties. Further, the copolyamide used in the present invention uses the copolyamide alone, and also contains other polyamide resins such as polyamide 6, polyamide 66, polyamide 610, and polyamide 12 as a main component. It is also possible to use mixed polyamide compositions in combination.

The copolyamide thus obtained has the characteristics of high viscosity, low crystallinity and crystallization rate, and excellent transparency, and is preferably used for extrusion molding such as film and blow molding. There is. However, when it is used for injection molding, the molding cycle becomes long and the moldability is reduced, so that it has never been used for injection molding. The present invention mixes the copolyamide and the modified polypropylene in a specific ratio so that the copolyamide can be used for injection molding applications, prevents deterioration of moldability due to injection molding, and improves mechanical strength and rigidity. In addition, a molded product excellent in warp deformation prevention and appearance is obtained.

In the resin composition obtained by mixing the copolyamide and the modified polypropylene, the amount of the copolyamide added must be 20 to 50% by weight in the resin composition. This is because if it is less than 20% by weight, excellent warp deformation prevention and appearance properties cannot be obtained, and if it exceeds 50% by weight, no further improvement effect is observed.

The glass fiber used in the present invention includes:
Glass fibers such as glass rovings, glass chopped strands and glass milled fibers which are manufactured and used for ordinary resin reinforcement may be used. The amount of glass fiber added should be 90:10 to 50:50 by weight of glass fiber with respect to the resin composition. When the content of the glass fiber is less than 10% by weight, a sufficient reinforcing effect cannot be obtained, and when it exceeds 50% by weight, melt-kneading becomes extremely difficult, melt flowability is deteriorated and workability is deteriorated, which is not preferable. .

In the present invention, the following various methods can be adopted as a method for obtaining the thermoplastic reinforced resin composition. For example, (1) a method in which a predetermined amount of each of a resin composition of modified polypropylene and copolyamide and glass fibers are mixed and then melt mixed. (2) After melt-kneading the resin composition into pellets,
A method of adding glass fibers and melting and kneading again. (3) Using an extruder equipped with a raw material supply port in the cylinder part in addition to the normal raw material supply port,
A method in which the resin composition is supplied, glass fibers are supplied from a supply port provided in a cylinder portion, and melted and kneaded. (4) A method in which modified polypropylene is supplied from a normal raw material supply port, and copolyamide and glass fiber are simultaneously supplied from a predetermined supply port closer to the outlet than the normal raw material supply port, and melt kneading is performed. Etc., and can be manufactured by any method.

As the mixing device, a normal mixing device such as a Henschel mixer (trade name), a mixer with a high-speed stirrer such as a super mixer, a ribo blender, and a tumbler may be used. Extruder is used. The melt-kneading temperature is 200 to 300 ° C, preferably 220 to 280 ° C. The pellets of the thermoplastic reinforced resin composition thus obtained are molded into a predetermined test piece by an ordinary injection molding machine, and using the test piece, mechanical strength, rigidity, heat distortion temperature, appearance and warp deformability are formed. Was measured.

The present invention will be specifically described below with reference to Examples and Comparative Examples. The test method of the present invention is based on the following method. 1) Mechanical strength was measured according to JIS K7113 (tensile strength). 2) The rigidity was measured according to JIS K7203 (flexural modulus). 3) Weld tensile strength was measured according to JIS K7113. 4) Izod impact strength is JIS K7110 (with notch)
It was done according to. 5) Heat distortion resistance is JIS K7207 (heat distortion temperature: load 18.6k
gf). 6) Appearance is ASTM D523 (surface gloss: incident angle 60)
°) according to. 7) The warp deformability was measured based on the measurement of the maximum warp deformation amount shown below. The amount of warpage is to measure a 150 mm square, 2 mm thick flat plate by injection molding, and use the obtained flat plate as a test piece for conditioning for 48 hours under the conditions of temperature 23 ° C. and RH 50%. Is the amount by which the test piece is warped. The measuring method is as follows: Place the adjusted test piece on the abdomen on a horizontal table, and fix both ends of one side with fingers so that one side of the test piece is in close contact with the table. In this state, the distance of the symmetry side away from the horizontal plane is measured. And the measured value was made into the amount of warpage deformation. For each piece (4 sides) of the test piece,
The amount of warp deformation was measured, and the maximum amount of warp was defined as the maximum amount of warp deformation, and the unit was expressed in mm.

[0021]

【Example】

Example 1 Melt flow rate (amount of molten resin discharged for 10 minutes when a load of 2.16 kg was applied at a temperature of 230 ° C.) 4.
5g / 10min crystalline polypropylene homopolymer 98.1
5% by weight maleic anhydride 1.0% by weight 2,6-di-
0.1% by weight of t-butylparazole, 0.1% by weight of calcium stearate, 0.05% by weight of 1,3-bis (t-butyl-peroxyisopropyl) benzene and 0.6% by weight of magnesium hydroxide were added to Henschel. Mix for 3 minutes with a mixer and melt-knead extrude at a temperature of 200 ° C. using a twin-screw extruder having a diameter of 45 mm and several raw material supply ports of L / D = 30. Modification of melt flow rate 130 g / 10 min Polypropylene pellets were obtained. The modified polypropylene and copolymerized polyamide (CM6001; melting point: 196 ° C., relative viscosity: 3.2 cP, hexamethylene diammonium adipic acid salt in the copolymer: 15% by weight, manufactured by Toray Industries, Inc.) are listed in Table 1. Put the amount in a tumbler mixer, and after mixing for 10 minutes to obtain a resin composition, supply the resin composition from the usual raw material supply port of the extruder, and the glass fiber from the supply port in the cylinder part to the resin. The composition and glass fibers were fed while being metered so that the compounding ratio was 65:35, melt-kneaded and extruded at a temperature of 250 ° C. and pelletized to obtain pellets of the thermoplastic reinforced resin composition. The pellets were put into an injection molding machine and the resin temperature was adjusted to 25
A predetermined test piece was molded at 0 ° C. and a mold temperature of 80 ° C. and subjected to various tests. The results are shown in Table 2.

Comparative Example 1 A test piece was prepared in accordance with Example 1 except that the copolyamide was not used. (Comparative Example 2) A test piece was prepared in accordance with Example 1 except that polyamide 6 (manufactured by Toray Industries, Inc.) was used as the copolyamide. (Comparative Example 3) Polyamide 66 as a copolyamide
(Manufactured by Toray Industries, Inc.) is used, and the kneading temperature of melt kneading extrusion pelletizing of the thermoplastic reinforced resin composition is 250 ° C. to 280 ° C.
A test piece was prepared in accordance with Example 1 except that the test piece was changed to. (Comparative Example 4) As a copolyamide, a mixture of 25.5% by weight of polyamide 6 (manufactured by Toray) and 4.5% by weight of polyamide 66 (manufactured by Toray) was used, and the thermoplastic reinforced resin composition was melted. Kneading Extrusion pelletizing kneading temperature is 2
A test piece was prepared in accordance with Example 1 except that the pellets of the thermoplastic reinforced resin composition were obtained by changing from 50 ° C. to 280 ° C. and the pellets were injection molded at a resin temperature of 280 ° C. and a mold temperature of 80 ° C. Created. (Comparative Example 5) EPR (JS
A test piece was prepared in accordance with Example 1 except that (R Company) was used. (Comparative Example 6) After obtaining a resin composition not using a copolyamide, the resin composition, mica (manufactured by Repco) and glass fiber (manufactured by Nippon Electric Glass Co., Ltd.) were mixed at a mixing ratio of 50:20:30. In addition, the resin composition and mica were mixed by a tumbler mixer for 10 minutes, and then fed from the usual raw material feed port of the extruder, and the glass fiber was fed from the feed port in the cylinder part. A test piece was prepared according to the above.

Example 2 Copolyamide CM600
1 was CM6141XF (melting point: 201 ° C., relative viscosity:
4.5 cP, adipic acid hexamethylene diammonium salt in copolymer: 10% by weight, manufactured by Toray Industries, Inc., except that a test piece was prepared in accordance with Example 1. (Example 3) Copolymerized polyamide CM6001 and CM62
41XF (melting point: 191 ° C., relative viscosity: 4.3 cP, hexamethylene diammonium adipic acid salt in copolymer: 20% by weight, manufactured by Toray Industries, Inc.), except that the test was conducted in accordance with Example 1. Created a piece. (Comparative Example 7) Copolyamide CM6001 is CM60
21 (melting point: 216 ° C., relative viscosity: 3.4 cP, hexamethylene diammonium adipic acid salt in copolymer: 5
% By weight, manufactured by Toray Industries, Inc.), except that the test piece was prepared in accordance with Example 1.

(Example 4) 70% by weight of modified polypropylene was changed to 80% by weight, and copolyamide (CM6001) was added.
A test piece was prepared in accordance with Example 1 except that 30% by weight was changed to 20% by weight. (Example 5) A test piece was prepared in accordance with Example 1 except that 70% by weight of modified polypropylene was changed to 50% by weight and 30% by weight of copolyamide (CM6001) was changed to 50% by weight. (Comparative Example 8) A test piece was prepared in accordance with Example 1 except that 70% by weight of modified polypropylene was changed to 90% by weight and 30% by weight of copolyamide (CM6001) was changed to 10% by weight. (Comparative Example 9) A test piece was prepared in accordance with Example 1 except that 70% by weight of modified polypropylene was changed to 40% by weight and 30% by weight of copolyamide (CM6001) was changed to 60% by weight.

Example 6 Except that the compounding ratio of the resin composition and the glass fiber was changed from 65:35 to 90:10.
A test piece was prepared in accordance with Example 1. (Comparative Example 10) The compounding ratio of the resin composition and the glass fiber was 6
A test piece was prepared in accordance with Example 1 except that the ratio was changed from 5:35 to 95: 5. The results are shown in Table 2.

[0026]

From the above results, the thermoplastic reinforced resin composition according to the present invention has a mechanical strength, rigidity, heat distortion temperature,
The balance of appearance and warp deformability is significantly improved compared to the comparative test piece, and it is suitable for electrical products, automobile parts, and various industrial products that require high strength, high rigidity, good appearance, and dimensional stability. It has been found that it can be suitably used in the field.

[0027]

[Table 1]

[0028]

[Table 2]

Claims (2)

[Claims] 1. An ε-aminocaproic acid portion of 75 to 93% by weight.
And hexamethylene diammonium adipic acid salt portion 7 to 2
Copolymerized polyamide consisting of 5% by weight 20 to 50% by weight
And modified polypropylene 50-80 modified with unsaturated acid
A thermoplastic reinforced resin composition, characterized in that glass fibers are mixed in a weight ratio of 90:10 to 50:50 with respect to a resin composition composed by weight. 2. An injection-molded article using the thermoplastic reinforced resin composition according to claim 1.