JPS60238341A - Polypropylene resin composition - Google Patents

Abstract

PURPOSE:The titled composition is obtained by adding a specific inorganic filler of a specific particle size together with mica to a crystalline polypropylene, thus being suitable for use as an industrial material for automobiles and electronics, because it has improved toughness, heat-distortion temperature and impact strength. CONSTITUTION:The objective composition is obtained by using (A) 40-90wt%, preferably 60-80wt% of a crystalline polypropylene with an MI of 1-60g/10min, (B) 5-40wt%, preferably 10-30wt% of mica with an aspect ratio of 5-120 and average particle sizes of 5-250mu, and (C) 5-40wt%, preferably 10-30wt% of calcium carbonate with an average particle size of 0.05-0.8mu, preferably cobalt calcium carbonate of 0.1-0.6mu average particle size or 5-40wt%, preferably 10-30wt% of barium sulfate with an average particle size of 0.1-0.9mu, preferably of 0.3-0.9mu.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a polypropylene resin composition which has excellent impact strength, high rigidity and heat distortion temperature, and is suitable as an industrial material in fields such as automobiles and light electrical appliances.

(Prior art) In order to improve the rigidity, mechanical strength, etc. of thermoplastic resins, especially polyolefin resins, it has been carried out to fill them with mica.
No. 8-17545). However, when polyolefin resin is filled with mica, there is a major drawback in that impact strength is significantly reduced.

In order to improve this reduction in impact strength, it has been proposed to add more rubber to the mix, but this has not yet been fully satisfactory due to problems such as a decrease in rigidity and heat distortion temperature. It has not been done.

(Problems to be Solved by the Invention) The present inventors have conducted intensive research to solve the above-mentioned conventional drawbacks, and as a result, we have found that a specific inorganic filler having an average particle diameter within a predetermined range is added to crystalline polypropylene. The present inventors have discovered that when blended with mica, the rigidity and heat distortion temperature are improved, and the impact strength is significantly improved, and the present invention has been completed.

(Means for Solving the Problems) That is, the present invention consists of (4) crystalline polypropylene (hereinafter referred to as component (A)) of 40 to 90% by weight, and ■) mica (hereinafter referred to as Φ) component. ) and (Q average particle size 0.
Calcium carbonate of 05-0.8μ or average particle size 0.
The present invention provides a polypropylene resin composition comprising 5 to 40% by weight of barium sulfate (hereinafter referred to as component (C)) having a particle size of 1 to 0.9μ.

The crystalline polypropylene used as component (4) in the present invention includes various types, such as propylene homopolymers, block copolymers and random copolymers of propylene and other copolymer components such as ethylene, and especially propylene-ethylene copolymers. Block copolymers and propylene homopolymers are preferred. The melt index (MI) of this crystalline polypropylene is 1 to 60,
F/10 minutes, preferably 2-1077710 minutes.

Here, the blending ratio of crystalline polypropylene is 40 to 90% by weight, preferably 60 to 80% by weight of the entire composition. If the blending ratio of crystalline polypropylene is less than 40% by weight, fluidity will decrease, which is undesirable;
If it exceeds 0% by weight, the effects of improving stiffness, heat distortion temperature, etc. will be insufficient, which is not preferable.

Next, in the present invention, mica is used as the component CB). The mica used has an aspect ratio of 5 to 120, preferably 30 to 70. Moreover, those having an average particle diameter of 5 to 250 μm are preferably used. Here, if the average particle diameter is less than 5 μm, the effect of improving rigidity is small. On the other hand, if the average particle diameter exceeds 250μ, the surface appearance of the composition deteriorates. Furthermore, (B)
As a component, it is more preferable to use mica treated with a 7-run coupling agent. Affinity can be improved by treatment with such a silane coupling agent. There are various silane coupling agents, such as vinyl ethoxy 7-nolan, vinyl trichlorosilane, vinyl tris (β-methoxyethoxy 7
Ran), r-glycidoxypropyltrimethoxysilane, α-aminopropyltriethoxysilane, r-aminopropyltriethoxysilane, r-methacryloxypropyltrimethoxysilane, N-β-(aminoethyl)
-r-aminopropyltriethoxysilane.

N-bis-(β-hydroxyethyl)-r-aminopropyltriethoxysilane, N-β-(aminoethyl/I/
) -1-Aminopropylmethyljethoxysilane, etc. Among these, it is preferable to use a compound having an amino group. This treatment with a silane coupling agent is usually carried out using 0.5 to 5% by weight of the silane coupling agent.

03) The blending ratio of the ingredients is 5 to 40% of the total composition,
Preferably the number is 10 to 301. (to) If the blending ratio of the components is less than 5% by weight, the stiffness will be reduced.

The dimensional improvement effect becomes small, and on the other hand, if it exceeds 4 o * m%, the fluidity decreases and the surface appearance deteriorates, which is not preferable.

Furthermore, in the present invention, calcium carbonate having an average particle diameter of 0.05 to 0.8 .mu.m or barium sulfate having an average particle diameter of 0.1 to 0.9 .mu.m is used as component (C).

When using calcium carbonate as component (0), it is necessary to use one with an average particle size of 0.05 to 0.8 μm, and in particular, use colloidal calcium carbonate with an average particle size of 0.1 to 0.6 μm. It is preferred that the average particle size of the calcium carbonate exceeds 0.8μ,
The impact strength decreases, and if it is less than 0.05 μm, the dispersion is insufficient and no impact strength improvement effect is observed, which is not preferable.

On the other hand, when barium sulfate is used as component (C), it is necessary to use one with an average particle size of 0°1 to 0.9μ, particularly one with an average particle size of 0.3 to 0°9μ. It is preferable. If the average particle diameter of barium sulfate exceeds 9μ, the impact strength will decrease, while if it is less than 001μ, the dispersion will be insufficient and no impact strength improvement effect will be seen, which is not preferred.

In the present invention, as component (0), it is necessary to use calcium carbonate or barium sulfate having an average particle size within the above specified range, and other than these three,
Alternatively, if any one of these three particles does not have an average particle diameter within the above-mentioned specific range, it is impossible to achieve the intended purpose of the present invention.

(0) The blending ratio of the ingredients is 5 to 40% of the total composition,
Preferably it is 10-30%. If the blending ratio of component (0) is less than 51% by weight, the effect of improving impact strength will be small, while if it exceeds 40% by weight, fluidity will deteriorate, which is undesirable.

The present invention basically consists of the above (4), CB), and (0).
However, if necessary, a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof may be added. Here, the polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof means a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, or a mixture of the modified polyolefin resin and an unmodified polyolefin resin,
As polyolefin resin, propylene homopolymer,
Polypropylene resins such as block copolymers and random copolymers of propylene and other copolymer components such as ethylene are preferred. In addition, unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid,
itaconic acid, crotonic acid, citraconic acid, sorbic acid,
These include mesaconic acid and angelic acid. Further, its derivatives include acid anhydrides, esters, amides, imides, metal salts, etc., such as maleic anhydride and itaconic anhydride.

Citraconic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, monoethyl maleate, acrylamide, -yleic acid monoamide, maleimide, N-butylmaleimide, sodium acrylate, sodium methacrylate etc. can be mentioned. Among these, maleic anhydride is preferred.The method for modifying polyolefins with these unsaturated carboxylic acids or derivatives thereof is not particularly limited, and various known methods can be used. For example, this is carried out by adding a radical initiator to polyolefin and maleic anhydride in the presence or absence of a solvent and heating the mixture. During the reaction, other monomers such as styrene or rubbers such as liquid rubber and thermoplastic rubber may also be present. Here, the modified polyolefin has an acid addition amount of 0.5 to 10
% by weight is preferred.

This modified polyolefin is processed into the above (4), CB),
(0) Mechanical strength can be further improved by adding 65 to 5 parts of O to 100 parts by weight of the total components.0 The composition of the present invention may also contain various additives as necessary. For example, an anti-fog agent, an ultraviolet absorber, an antistatic agent, etc. may be added as appropriate.

The polypropylene resin composition of the present invention can be obtained by blending the above-mentioned components in predetermined amounts and sufficiently kneading the mixture by a dry/wet/melt mixing method, a multistage melt mixing method, a simple melt mixing method, or the like. The mixing can be carried out in a conventional manner using a Nokunbury mixer, a co-kneader, an extruder, a twin-screw kneader, etc., and is usually carried out at a temperature of 180 to 250°C.

(Effects of the Invention) Since the polypropylene resin composition of the present invention contains a specific inorganic filler having an average particle size within a specific range, it can be used as a Z8 binder with higher impact resistance than conventional ones. Nu n
In addition, the polypropylene resin composition of the present invention has excellent rigidity and heat distortion temperature.

Therefore, the polypropylene resin composition of the present invention can be effectively used as an industrial material in fields such as automobiles and light electrical appliances.

(Example) Next, examples of the present invention will be shown.

Examples 1 to 10 and Comparative Examples 1 to 10 Predetermined crystalline polypropylene (component (A)), mica (
(B) component), calcium carbonate or barium sulfate having a predetermined particle size ((C) component), and modified polyolefin are blended in the proportions shown in Table 1, triblended, and then kneaded using a twin-screw kneader. A resin composition was obtained. Table 1 shows the measurement results of the physical properties of the obtained composition.

Note) a: Propylene-ethylene block copolymer (MI 6
g710 min, ethylene content 9% by weight) b: Propylene homopolymer (MI ag/lo min) C: average particle size 9
d: Mica with an average particle size of 40μ and an aspect ratio of 30 treated with α-aminopropyltriethoxysilane e: Colloidal calcium carbonate with an average particle size of 0.15μ f: Average particle size of 0.0μ and an aspect ratio of 50 treated with α-aminopropyltriethoxysilane. 6μ colloidal calcium carbonate g: precipitated barium sulfate mu with average particle size 0.6μ h: ground calcium carbonate with average particle size 3.8μ 1: colloidal calcium carbonate with average particle size 0.03μ j: average particle size 4.6μ barium sulfate *1: Polypropylene modified with maleic anhydride (# added amount: 5%) *2: Based on AS'l'M D256 (with notch) *3: Based on A8TM D638 *4: Compliant with A8TM D 790 *5: A8
Compliant with TM D 648 (load 18.6 rise) *6
: Ethylene-propylene rubber (Mooney viscosity wind, +4 (100) 24) Patent applicant: Idemitsu Petrochemical Co., Ltd. Procedural amendment (spontaneous) June 8, 1981 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication special of the case Application No. 54L-91925 2. Name of the invention Polypropylene resin composition 3. Relationship with the case by the person making the amendment Patent applicant Idemitsu Petrochemical Co., Ltd. 4. Agent ■104 Address 1-1-10 Kyobashi, Chuo-ku, Tokyo Nishikan Building 5th Floor Name (7407) Patent Attorney Kubo 1) Fuji 6th Department Telephone (27)
5) No. 0721 No. 5, Target of correction 6, Contents of correction (1) Delete "α-amino, noprobiltriethoxysilane," in lines 5 to 4 from the bottom of No. 4 of the specification.

(2) Correct [α-aminopropyltriethoxysilane] in lines 6 and 7 on page Z of the same ff1l to “γ-aminopropyltriethoxysilane”.

(that's all)

Claims (1)

[Claims] 1. (A) 40 to 90% by weight of crystalline polypropylene. A polypropylene resin composition comprising (to) 5 to 30% by weight of mica and (0) calcium carbonate having an average particle size of 0605 to 0.8 μm or barium sulfate having an average particle size of 0.1 to 0.9 μm.