JPH03215556A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition excellent in moldability, heat resistance, rigidity, water resistance and surface properties by adding a layered silicate to a mixture of a polyamide resin with a polyarylene sulfide resin. CONSTITUTION:A resin composition comprising a polyamide resin (A), a polyarylene sulfide resin (B) and a layered silicate (C) homogeneously dispersed in components A and/or B. The mixing ratio is such that about 0.05-30 pts.wt. component C is mixed with 100 pts.wt. mixture of about 10-90wt.% component A with about 90-10wt.% component B. A desirable component A is a resin having an average mol.wt. of 9000-30000. A desirable component B is a resin having at least 70mol%, based on the total repeating units, repeating units of formula I. Examples of component C include smectite clay minerals such as montmorillonite and hectorite, vermiculite and barroisite, and especially montmorillonite is desirable.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has excellent moldability, and its molded products have excellent heat resistance, rigidity, water resistance, surface properties, and impact resistance (surface impact resistance). The present invention relates to a resin composition having the following.

[Prior Art] Polyamide resins generally have excellent abrasion resistance, impact resistance, moldability, chemical resistance, and mechanical strength, but they suffer from problems such as loss of regularity and dimensional changes when water is absorbed. There is.

Materials mixed with glass fibers or inorganic fillers have traditionally been used to reduce dimensional changes when water is absorbed and to improve the decrease in rigidity when water is absorbed. The field of application has been limited due to problems with surface impact resistance) and surface properties.

Recently, two or more types of polymers have been mixed (
Attempts have been made to solve these problems using polymer alloys. An invention has been proposed that maintains the excellent properties of polyamide resin while improving the drawbacks of changes in dimensions and rigidity due to water absorption.

However, when mixing two or more types of polymers to give a resin multiple different excellent performances, the two
Of course, the melting point of seeds or larger polymers is
They often have different properties such as crystallinity and are difficult to mix with each other. Therefore, the key point in alloying technology for polymer alloys is how to make two or more types of polymers compatible and obtain an ideal dispersion shape and particle size.

Normally, it is said that it is preferable for incompatible polymer alloys to have a seabird structure, which consists of a 71-RIX resin that forms the sea area and a domain resin that forms the island area, and the dispersed shape of the island area. The particle size of the particles has a great influence on the physical properties. The shape and particle size of these islands (domains) depend on the appropriate dispersion shape and grain size depending on the resin used.
Although the particle size varies, as stated in many patents, it is preferable that the average particle size is 1 to 2 p7n or less.

However, by simply mixing resins, the average particle size of the islands can be reduced by 1
~2prn'd below is difficult. Therefore, several techniques have been announced that allow the average particle size to be reduced to 1 to 2 μm or less by adjusting the phase}δ properties of the resins and further devising the mixing method.

In addition, there is a theoretical limit to the lower limit of the average particle size of the islands, which is beyond the optimal range, but in reality, the current technology stage β has been developed to determine how to reduce the average particle size of the islands in most combinations of resins. The key points are to reduce the size and improve physical properties such as impact resistance, moldability, and impact resistance. Regarding the shape, it is better to make it as close to a spherical shape as possible in order to prevent deformation of the molded product.
Regarding uniformity, it is important that there is little variation in the average particle size, and in particular that there are no particles that are extremely large compared to the average particle size.

In one patent, compatibility is improved by introducing a functional group that has an affinity for the polymer to be alloyed or by using a third component that has an affinity for two or more polymers as a compatibilizer. It is discussed how to improve the dispersion of the islands and improve the physical properties.

However, the existing methods have not sufficiently dispersed the islands;
In particular, even if the average particle size is fine, the shape and uniformity are still insufficient.
Materials or techniques for obtaining materials with excellent performance in a well-balanced combination of heat distortion temperature and impact resistance have not yet been developed.

[Problems to be Solved by the Invention] As mentioned above, a product that satisfies all the properties of moldability, heat resistance, rigidity, water resistance, surface properties, and impact resistance by modifying conventional polyamides (bolymer alloy, etc.) have not yet been developed, and there is currently a strong desire to develop a material that also has these properties.

The present inventors conducted extensive research with the aim of developing a resin with excellent moldability, heat resistance, rigidity, and water-resistant surface properties.As a result, by blending polyamide resin and polyarylene sulfide resin, The inventors have found that the object can be achieved and have completed the present invention.

[Means for Solving the Problems] The composition of the present invention is based on the morphology of a sea-island structure of two or more resins, and relates to a composition consisting of a combination of a solid material serving as the core of the island portion. The inorganic material that will become the core is selected to match the particle size of the desired island part, and is dispersed in a fine state in advance in the resin that is to be made into the island part. A composition is prepared by melt kneading or pellet blending with the desired resin. or
When melting and kneading the sea area and island area, the inorganic substance is simultaneously mixed in a well-dispersed manner to create a composition. In some cases, an inorganic substance is previously dispersed in the resin that is to become the sea part, and the resin is melt mixed or pellet blended with the resin that is to be the island part to create a composition. The composition of the present invention is a composition in which the dispersion of islands in the polymer alloy obtained by such a method is improved, the particle size and shape are made uniform, and the particles are further refined.

In the present invention, which of component (A) and component (B) is
The silicate may be contained in either or both of the components (,) and (B), and the silicates present in the islands make the islands fine and uniform. It improves the rigidity and heat resistance of the island parts, and those present in the sea area improve the rigidity and heat resistance of the entire resin, and also have a positive effect on the dispersion of the island parts.

The contents will be explained in detail.

The composition of the present invention is (A) polyamide resin 10-90! f
fi% and (B) polyarylene sulfide resin 9
0 to 10%, and (C) the layered silicate in the (A) and/or (B) components.
) A resin composition in which 0.05 to 30 parts by weight of the components are uniformly divided based on 100 parts by weight of the total amount of the components.

The polyamide resin of component (A) constituting the composition of the present invention has an acid amide bond (-CONH-) in the molecule, and specifically, ε-cabrolactam, 6-
Polymers or copolymers obtained from aminocabronic acid, ω-enane]-lactam, 7-aminohbutanoic acid, 1l-aminoundecanoic acid, 9-aminononanoic acid, α-pyrrolidone, α-piveridone, hexamethylene Polymers or copolymers obtained by polycondensation of diamines such as amines, nonamethylene diamine, undecamethyl nondiamine, dodecamethylene diamine, metaxylylene cyanine, etc., and sicarboxylic acids such as terephcuric acid, isophthalic acid, acibic acid, and sebacic acid. 3- and exemplify combinations or mixtures thereof. The polyamide resin of component (A) is
Those having an average molecular weight of 9,000 to 30,000 are preferred.

The polyarylene sulfide resin used in the present invention is
From the viewpoint of heat resistance, chemical resistance, and mechanical properties, it is not preferable that the repeating units are 70 mol % or more and the structural formula arylene sulfide units are 70 mol % or less because the white heat resistance is decreased. The remaining 30% (here, R is selected from the group consisting of an alkyl group or an alkoxy group having 12 or less carbon atoms, a phenyl group, and a nitro group) includes trifunctional phenyl sulfide bonds and the like.

In the present invention, a polyarylene sulfide resin having the above structure is provided. A melt flow rate of 5 to 10,000 g/10 minutes, more preferably 15 to 5,000 g/10 minutes, as measured by a melt indexer specified in STM D 1238 at 315° C. and a load of 5 kg, is used.

In addition, for applications where jffl mobility is particularly required, ponoarylene sulfide resins with melt fluorate of 5 to 300 g/10 min and 400 to 10,000 g/10 min.
It is preferable to use a resin mixture obtained by mixing 10 min.

The distribution ratio of components (A) and (B) is that component (A) is 10
~90 parts by weight, and component (B) is 90 to 10 parts by weight. If the blending ratio of component (A) is less than 10 parts by weight, moldability will decrease, and if it exceeds 90 parts by weight, rigidity upon water absorption will decrease.

Component (C) is a layered silicate. This component (C) is used to replace component (B) with (A) in a molded article obtained from a resin composition.
Component (A) is finely dispersed in the polyamide of component (B), and is a substance that contributes to imparting mechanical properties with excellent moldability, heat resistance, and surface impact resistance. .

Furthermore, the uniformly dispersed layered silicate has the characteristic of imparting rigidity and finely dispersing the resin that becomes the dispersed particles. This is an essential component for providing a method for stabilizing a multi-component polymer blend, which is completely different from the known method of imparting stiffness and impact resistance using the known technique of "+fi".

The layered silicate is characterized in that when dispersed in component (A), each layer maintains an average interlayer distance of 20 or more and is uniformly dispersed. In the present invention, the layered silicate refers to a unit of material with a side length of 0.002 to 1 mm and a thickness of 6 to 20 mm.

In addition, the interlayer distance refers to the distance between the centers of gravity of the flat plates of layered silicate, and uniform dispersion means that each sheet of layered silicate is distributed in parallel, or a multilayered structure with an average overlap of 5 or less layers is distributed in parallel. Or, it refers to a state in which 50% by weight or more, preferably 70% by weight or more, is dispersed randomly or in a mixed state of parallel and random without forming local lumps.

As a raw material for such a layered silicate, a layered phyllosilicate mineral composed of a layer of magnesium silicate or aluminum silicate can be exemplified. Specifically, examples include smectite clay minerals such as montmorite, saponite, beidellite, nontronite, hex-1-lite, stevensite, vermiculite, paloysite, etc., and these are natural minerals. Among these, montmorillonite is preferred.

The blending ratio of component (C) is 0.05 to 30 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the total amount of components (A) and (B). When the blending ratio of component (C) is less than 0.05 parts by weight, the effect of improving the heat resistance and impact resistance of the molded product is small, and when it exceeds 30 parts by weight, the fluidity of the resin composition is extremely reduced. However, the moldability decreases.

Furthermore, in addition to the above-mentioned components (A), (B), and (C), impact resistance modifiers can be added to the present invention as needed. The impact resistance improver is not particularly limited as long as it is an impact resistance improver generally used for polyamides, and the following examples may be used. When 20% by weight is added to polyamide, its impact resistance is more than doubled,
Its bending modulus is 10. O O O kg/c
m2LJ is below.

Examples of impact resistance modifiers include styrene-butadiene (or isobrene) copolymers (random copolymers, block copolymers, hydrogenated block copolymers, and graft copolymers) that are elastomeric at room temperature; Copolymers of polyolefins can be exemplified. Specifically, styrene-butadiene random copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, hydrogenated styrene-isoprene -Styrene block copolymer: A copolymer of two or more olefins selected from ethylene, propylene, butene-1, hexene-1, decene-1, 4-methylbutene-4-methylpentene-1, etc. can be exemplified.

This cutting impact improving material can be modified with unsaturated carboxylic acid or the like.

A preferable amount of the impact modifier for use in the present invention is 30 parts by weight or less based on 100 parts by weight of the total amount of components (A), (B), and (C). If it exceeds 30 parts by weight, moldability decreases,
This is not preferred because the heat resistance of the molded product decreases.

The compatibilizing agent is, for example, 70 parts by weight of poly(ethylene/glycidyl methacrylate) copolymer (ethylene/glycidyl methacrylate = 85/15) and poly(butyl-b-styrene acrylate) having a peroxide bond in the side chain. (butyl acrylate/styrene-10/90) and 30 parts by weight of poly(ethylene/glycidyl methacrylate) obtained by melt-kneading 30 parts by weight of poly(ethylene/glycidyl methacrylate) using a melt extruder at a melting temperature of 200±20°C. A grafted polyolefin modified product (butyl acrylate (b-styrene) (grade name: MODIPA-A4 100, manufactured by NOF Corporation), etc. may be used.

The composition of the present invention may contain dyes, pigments, nucleating agents,
Fillers such as mold release agents, reinforcing agents such as glass fiber, metal fiber, carbon fiber, plasticizers, lubricants, heat resistance imparting agents, foaming agents,
Flame retardants, etc. can be recorded. The method for producing the resin composition of the present invention is not particularly limited. For example, after contacting the layered silicate of component (C) with a swelling agent to widen the interlayer space in advance to facilitate the incorporation of monomers between the layers, the monomers forming component (A) are mixed and polymerized (JP-A-62 -Refer to Publication No. 74957)
Then, mix component (B) and heat at 230-250°C.
, preferably melted at 250-320°C. Who wants to go to Konshito?
(B) in the polyamide in a molten state after the completion of polymerization.
It is possible to apply a method of mixing and blending a molten component with a layered silicate of component (C) in which the interlayer distance is increased to 50 or more.

In the resin composition of the present invention, it is preferable that particles that can become dispersed particles have a number average particle diameter of 2 pm or less to form a dispersed phase.

The layered silicate of component (C) may be dispersed in both the phases of component (A) and component (B), or may be dispersed in one of the phases.

In the present invention, by further blending a layered silicate into the mixture of components (A) and (B), both the heat resistance and impact resistance of a molded article can be improved at the same time. Generally, when an inorganic filler is blended into a mixture of polyamide resin and thermoplastic resin, rigidity and heat resistance can be improved, but impact resistance is reduced. However, in the composition of the present invention, the layered silicate is dispersed in a very fine state, and even with a small amount of addition, the rigidity and heat resistance can be improved. Since it can be finely dispersed, it is thought that rigidity, heat resistance, and impact resistance are improved.

The resin composition of the present invention can be used as a manufacturing material for various automobile parts, electronic and electrical parts, mechanical parts, and general miscellaneous goods. (Example) Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that parts represent parts by weight. Moreover, the test method for each characteristic shown below is as follows.

Tensile strength: ASTM D-638 Bending strength, flexural modulus: ASTM D-790 Izod impact strength: ASTM D-256 Heat distortion temperature: A
STM D-648 High-speed impact strength: First, a pellet of the resin composition of the present invention was molded into a disk with a thickness of 3.2 mm and a diameter of 100 mm, and the disk was used as a test piece. Next, reduce the tip diameter to 1/2 at -30°C.
An inch round missile is placed at the center of the test piece at a distance of 2.5m/
A surface impact measurement method (UBE method) was used in which the fracture energy was calculated from the area of the stress-strain curve at the time of fracture by dropping the specimen at a speed of seconds.

Dispersed Particle Size Small pieces of each molded body were prepared using a cyclotome, and the pieces were stained with rhodamine B, washed with water, and then the dispersed particle size in the pieces was measured using an optical microscope (x1ooo).

Examples and Comparative Examples Resin compositions were produced using the combinations and blending ratios of each component shown in the table below, and test pieces for each characteristic evaluation were produced as molded bodies. (A) The average thickness of one unit of polyamide layered silicate is 9.5 mm, and the average length of one side is approximately 0.5 mm. Disperse 200 g of montmori kuchinite of l/7711 in 10!2 water, add 51.2 g of 12-aminododecanoic acid and 24 ml of concentrated hydrochloric acid,
After stirring for a minute, it was filtered.

After thoroughly washing this, it was vacuum dried. Through this operation, a complex of 12-aminododecanoic acid ammonium ion and montmorillonite was prepared. The layered silicate content in the composite was 80% by weight. Furthermore, as measured by X-ray diffraction of this composite, the distance between silicate layers was 18.0. Next, 10 kg of ε-cabrolactam, 1 kg of water, and 200 g of the dried composite were placed in a reaction vessel equipped with a stirrer, and the mixture was stirred at 100° C. so that the inside of the reaction system became uniform. The temperature was further raised to 260°C, and the mixture was stirred for 1 hour under a pressure of 15 kg/cm2. Thereafter, the reaction was carried out under normal pressure for 3 hours while reducing the pressure and volatilizing the water from the reaction vessel. After the reaction was completed, the reaction product taken out in the form of a strand from the lower nozzle of the reaction vessel was cooled with water and cut to obtain a pellet made of polyamide resin (average molecular weight 15.000) and montmorillonite. Next, soak this pellet in hot water,
After extracting and removing unreacted monomers (about 10%),
Dry in vacuo. The ratio of polyamide and montmorillonite in this dry pellet is 10% polyamide resin.
The amount of montmorillonite was 1.6 parts by weight relative to 0 parts by weight.

(B) Polyarylene sulfide (Toblen (polyphenylene sulfide manufactured by Kiki) Grade name: Toblen T
4, hereinafter abbreviated as PPS) Impact resistance modifier modified ethylene propylene random copolymer (Exxon Chemical (example grade name: EXXELORRUAl803, hereinafter abbreviated as modified EPR) molded body was manufactured by the following method. First, as shown in the table. After pre-mixing the indicated amounts of each component, they were melt-kneaded and pelletized at 250°C-300''C using an extruder with a screw diameter of 30mm.Then, the pellets were vacuum-dried, and then molded into cylinders using an injection molding machine. temperature 25
Injection molding was carried out under conditions of 0 to 300°C and a mold temperature of 80°C to obtain a molded product.

The obtained molded body was used as a test piece for each characteristic evaluation. The results of the evaluation tests are shown in the table.

(Effects of the Invention) As shown in the table, by further blending a layered silicate into the mixture of polyamide resin and polyanolene sulfide resin, not only rigidity but also excellent impact resistance is achieved.

Claims (1)

[Claims] A resin consisting of (A) a polyamide resin, (B) a polyarylene sulfide resin, and (C) a layered silicate uniformly dispersed in (A) and/or (B) components. Composition.