JPH0428732A - Polyolefin resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polyolefin resin composition.

Polyolefin resin has excellent moldability and mechanical strength,
It is widely used in industrial fields as a low-density, inexpensive molding material. However, automobile parts, electrical and electronic parts,
In particular, its use in mechanical parts has been limited due to insufficient heat resistance and rigidity.

The present invention provides a polyolefin resin composition with improved heat resistance and rigidity, which is suitable for the above-mentioned uses.

[Conventional technology]

It is well known that glass fibers and carbon fibers are added to polyolefin resins to compensate for their lack of heat resistance and rigidity. Smoothness may be lost.

Additionally, in order to reinforce heat resistance, many polymer blending techniques have been proposed in which engineering resins are blended, but in order to obtain a sufficient effect from reinforcing with resin, it is generally necessary to blend a relatively large amount of reinforcing resin. In many cases, the original characteristics of the polyolefin resin may be impaired or the impact strength may be reduced.

On the other hand, resins that can form an anisotropic melt phase (hereinafter sometimes referred to as liquid crystal resins) have extremely excellent rigidity, heat resistance, etc., and can be expected to have an improvement effect even when mixed in small amounts as reinforcing resins. Ru.

Regarding the application of this liquid crystal resin to a polyolefin resin, JP-A No. 64-66265 proposes a composition consisting of polyethylene terephthalate, a liquid crystal resin, and a polyolefin. It is only 10% by weight, and there is no suggestion that it is effective in improving the performance of polyolefin resins.

[Problem to be solved by the invention]

We investigated a method of blending a small amount of liquid crystalline resin with a polyolefin resin to improve the heat resistance and rigidity of the polyolefin resin, and at the same time suppress the decline in impact strength that generally occurs with mutually incompatible resin blends.

[Means for Solving Problem 5] The present inventors have found that a composition containing a polyolefin resin, a resin capable of forming an anisotropic melt phase, and a modified polyolefin containing a silicon compound residue achieves the above object. The inventors have discovered that the present invention can be obtained.

That is, the polyolefin resin composition of the present invention consists of the following three components (A>: 50 to 95% by weight of polyolefin resin)
and component (B), a silicon compound residue represented by the general formula % (where R is an aliphatic hydrocarbon group, Y is a hydrolyzable organic group or hydroxyl group, and n is Oll or 2). Component (C) Resin 2 to 4 capable of forming an anisotropic melt phase to 100 parts by weight of a mixture consisting of 50 to 5% by weight of modified polyolefin.
0 parts by weight.

The present invention will be explained in more detail below.

(Components) Component (A) Polyolefin resin Component (A) used in the present invention is a polyolefin resin having 2 to 10 carbon atoms such as ethylene, propylene, butene, hexene, etc.
It includes homopolymers of olefins, copolymers of these α-olefins, and copolymers of other unsaturated monomers copolymerizable with these α-olefins.

Specifically, low density polyethylene, high density polyethylene, ethylene-propylene copolymer, ethylene-butene-
1 copolymer, ethylene-hexene 1 copolymer, polypropylene, propylene-ethycine copolymer, polybutene-
1. Butene-1-ethylene copolymer, poly-3-methyl-butene-1,3-methyl-butene-1-ethylene copolymer, 3-methyl-butene-1-propylene copolymer, poly4-methyl -Pentene-1 etc. are exemplified. Examples of other unsaturated monomers include styrene, divinylbenzene, maleic acid, maleic anhydride, acrylic acid, methyl acrylate, methacrylic acid, methyl methacrylate, 4-methyl-1,4-hexadiene, and acetic acid. Examples include vinyl. Two or more of these polyolefin resins can be used in combination. Preferably, low density polyethylene, high density polyethylene, ethylene-α-olefin copolymer, polypropylene, propylene-ethylene copolymer, maleic anhydride grafted polypropylene, poly-3-methyl-butene-1, poly-4 -Methyl-pente>・-1.

Component (B) Modified Polyolefin The component (B) used in the present invention, a polyolefin modified with a silicon compound having a hydrolyzable organic group, can be produced, for example, by the following method.

That is, a method of graft copolymerizing ethylenically unsaturated nitrogen onto a copolymer containing polyethylene and ethyne as the main components, or a copolymer containing polypropylene and propylene as the main components in the presence of a radical-generating agent. (Refer to Japanese Patent Publication No. 48-1711, Japanese Unexamined Patent Publication No. 59-36115, etc.), or a method by high-pressure radical copolymerization of ethylene, ethylenically unsaturated silane, and optionally a radically polymerizable monomer (Japanese Patent Publication No. 62 -237
77, etc.) is typically manufactured.

However, in the present invention, the method for producing the modified polyolefin of the five components (B) is not limited to the above method; for example, maleic anhydride modified polyolefin and γ
- Any method can be applied, such as a method of obtaining it by reacting aminopropyltrimethoxysilane. Furthermore, the silicon compound for modification is not limited to ethylenically unsaturated silane.

Examples of silicon compounds for modification include silicon compounds that have a reactive group that can be grafted onto the olefin polymer, silicon compounds that have a group that can react with the functional group introduced into the olefin polymer, or reactive silicon compounds that can be copolymerized with the olefin monomer. There are silicon compounds having a group, and generally compounds of the following formula are mentioned: R'S i RY 3-.

Here, R' is, for example, a vinyl group, allyl group, isopropenyl group, butenyl group, cyclohexenyl group, or γ-(
meth)acryloyloxypropyl group, etc. R is a hydrocarbon group such as an alkyl group such as a methyl group, ethyl group, propyl group, or decyl group. Y represents a hydrolyzable organic group or a hydroxyl group, and n is 0.1 or 2.

Examples of Y include methoxy group, ethoxy group, formyloxy group, acetoxy group, propionyloxy group, alkyl or arylamino group.

Particularly preferred as the silicon compound for modification is CH2=
CHS i (OA ) s (where A has 1 carbon number
- 8 alkyl group), specific examples include vinyltrimethoxysilane and vinyltriethoxysilane.

As the polyolefin modified with the silicon compound having a hydrolyzable organic group as described above, the above (A)
In addition to the polyolefin resins listed in the components, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-butene-1 copolymer,
Examples include elastomers such as ethylene-butylene/-1-conjugated diene copolymer.

The amount of modifier in component (B> is usually 5% by weight or less,
Preferably it is 3 to 0.1% by weight. If the amount of the modifier is more than this, the crosslinking reaction due to the silanol condensation reaction between the modified resins may progress during the resin mixing process, resulting in a decrease in moldability and mechanical strength of the resulting composition. .

Component (C): Resin capable of forming an anisotropic melt phase The component (C) used in the present invention, a resin capable of forming an anisotropic melt phase, is well known as a so-called liquid crystal resin. Confirmation of the anisotropic molten phase can be carried out by polarized m-microscopic observation of a sample in a molten state.

That is, under the orthogonal conditions of the polarizer and analyzer, it is recognized that light is transmitted due to optical anisotropy.

The general structure of liquid crystal resin is a semi-aromatic polyester consisting of an aliphatic diol, an aromatic dicarboxylic acid, and an aromatic hydroxycarboxylic acid, an aromatic diol and an aromatic dicarboxylic acid, or an aromatic diol and an aromatic dicarboxylic acid. A wholly aromatic polyester consisting of an aromatic hydroxycarboxylic acid or only an aromatic hydroxycarboxylic acid is known. Here, as the aliphatic diol, for example, ethylene glycol, 1,3-propylene glycol, 1,4-butene glycol, 1.6-hexene glycol, 1,12-dodecamethylene glycol, etc., and as the aromatic diol, For example, 1,4- or 1,3-dihydroxybenzene, 4,4' or 3.
3'-dihydroxydiphenyl, 2,2-bis(4'-
hydroxyphenyl)propane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydipheny! Resa! lefone, 4,4'-dihydroxydiphenyl sulfide, 1,4-dihydroxynaphthalene, 2
, 6-dihydroxynaphthalene, 1,6 dihydroxynaphthalene, etc., and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, diphenyl-4,4'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, and naphthalene-1,4-dicarboxylic acid.
2,6-dicarboxylic acid, diphenylresa Ilefone-4
, 4'-cicaflebonic acid, cy'phenyl ether-4,
Examples of aromatic hydroxycarboxylic acids such as 4'-dicarboxylic acid include 4-hydroxybenzoic acid, 4-hydroxydiphenyl-4'-carboxylic acid, 2-hydroxy-6-naphthoic acid, 1-hydroxy-4-naphthoic acid, etc. can be mentioned.

Note that the benzene ring and naphthalene ring may be substituted with a lower alkyl group, an aryl group, or a halogen group.

Specific examples of component (C) used in the present invention include polyesters consisting of ethylene glycol, terephthalic acid and 4-hydroxybenzoic acid, and polyesters consisting of 1,4-dihydroxybenzene, terephthalic acid and 4-hydroxybenzoic acid. , 4.4'-polyester consisting of dihydroxydiphenyl, terephthalic acid and 4-hydroxybenzoic acid, polyester consisting of 4.4'-dihydroxydiphenyl, isophthalic acid and 4-hydroxybenzoic acid, 2-hydroxy-6- Typical examples include polyester consisting of naphthoic acid and 4-hydroxybenzoic acid. These include, for example, Eastman's ' It is commercially available under the trade names of ``Zydar'' from Taiha Kagaku Kogyo Co., Ltd., ``Econol'' from Hoechst Celanese and Polyplastics, and ``Pictrex'' from ICI Japan.

The liquid crystal resin that can be used in the present invention is one that exhibits optical anisotropy in a molten state, that is, a so-called liquid crystal state.
Although not particularly limited, from the viewpoint of moldability, the melting point is 35
A temperature range of 0°C to 100°C is preferred. melting point is 3
When the temperature exceeds 50°C, the moldability of the composition decreases, high-temperature molding becomes necessary, and thermal deterioration of the composition tends to occur. Further, if the melting point is less than 100°C, heat-resistant reinforcement, which is one of the effects of the present invention, is not sufficient.

(Component Composition) The composition of the components in the present invention is as follows: component (A) 50 to 95% by weight, preferably 70 to 85% by weight of polyolefin resin, and component (B) 50 to 5% of modified polyolefin containing silicon compound residue. %, preferably 30
to 15% by weight and component (C) a resin capable of forming a oriented melt phase in an amount equal to or less than 100% by weight of component (A) and component (B).
The amount ranges from 2 to 40 parts by weight, preferably from 5 to 30 parts by weight, and most preferably from 10 to 20 parts by weight.

Component (C) is a reinforcing agent for the heat resistance and rigidity of polio and fin resin, and as the amount of the compound increases, the reinforcing effect becomes more noticeable, but the total amount of component (A) and component (B) is 100. If the amount exceeds 40 parts by weight, the strength and impact strength of the molded article may decrease.

Component (B) is effective in improving the miscibility of component (A) and component (C), but if it is used in a total amount exceeding 50% by weight with component (A), the desired heat resistance will be reduced. The effect of improving properties and rigidity tends not to be fully realized.

The dispersed particles of component (C) dispersed in the polyolefin resin and modified polyolefin preferably have a volume average particle diameter of 500 microfron LJ or less, more preferably 30 to 1 micron.

When the grain size is reduced to more than 1 micron, the reinforcing effect on rigidity and heat resistance tends to decrease.

(Additional Components) In the present invention, other additional components can be added to the composition consisting of the components (A), (B), and (C). For example, organic and inorganic fillers and reinforcing agents, especially glass fiber, mica 5 talc, wollastonite, potassium titanate, calcium carbonate, and silica, are effective in improving rigidity, heat resistance, dimensional accuracy, dimensional stability, etc. be. Depending on the actual use, various known colorants and dispersants thereof can be used.

Furthermore, rI4 impact strength improvers such as copolymers consisting of unsaturated epoxy compounds and ethylene, copolymers consisting of unsaturated epoxy compounds, ethylene and ethylenically unsaturated compounds, styrene-butadiene copolymer rubbers and their Hydride, ethylene-propylene (diene)
#: The addition of polymer rubbers, as well as their modified products with α, β-unsaturated carboxylic acid anhydrides, unsaturated glycidyl esters, and unsaturated glycidyl ethers, is effective in improving the impact strength of the composition. It is.

Furthermore, well-known additives such as antioxidants, weather resistance improvers, nucleating agents, flame retardants, and slip agents can be used in polyolefin resins.

(Manufacture of composition) The resin composition of the present invention is produced by mixing the above-mentioned components in various kneading machines,
For example, it can be produced by cross-mixing in a screw extruder, twin screw extruder, Banbury mixer, or the like. Further, the order of mixing may be any possible order, but when mixing by melt kneading, it is preferable to mix sequentially starting from the one with the highest viscosity.

〔Example〕

The present invention will be explained in detail below using Examples and Comparative Examples, but the scope of the present invention is not limited thereby.

The composition of the test piece for evaluation and the predetermined formulation for evaluation were mixed at 280° C. in a PCM twin-screw extruder manufactured by Ikegai Tekko Co., Ltd. to obtain a pellet of the composition. After drying this pellet for 12 hours in a vacuum dryer set at 120°C, a predetermined test piece was prepared at 280°C using an M40A-8J injection molding machine manufactured by Meiki Seisakusho Co., Ltd.

Evaluation was based on flexural modulus (23°C, JIS K7203),
Heat distortion temperature (4.6 kg load, JIS K7110),
A reverse impact test (impact from the opposite direction of a notch, JIS K7110) was conducted.

1) Polypropylene: Mitsubishi Polypro MA manufactured by Mitsubishi Yuka Co., Ltd.
8J, melt flow rate 1.0 g/10 minutes, 2) Polyethylene: Mitsubishi Polyethylene HY4 manufactured by Mitsubishi Yuka Co., Ltd.
30+-melt flow rate 1.0 g/10 minutes, 3) Silicon compound modified polypropylene; manufactured by Mitsubishi Yuka Co., Ltd. "Linkron XPM800HMJ, melt flow rate 7
0g, 'IO min.

4) Silicon compound modified polyethylene, manufactured by Mitsubishi Yuka Co., Ltd. [Linkron HF70ON+, Melt Flowray-] 0.8 g/
10 minutes 5) Liquid crystal resin; “Vectra A9” manufactured by Polyplastics
50J, melting point 273°C Table 1 shows the results of evaluating the relationship between the ratio of polypropylene and silicon compound-modified boria pyrene and performance.

Table 2 shows the results of investigating changes in performance due to an increase in the amount of liquid crystal resin blended.

As can be seen from Table 1, the composition of the present invention has a heat resistance with a heat distortion temperature of 110°C or higher and an impact strength of 20ky·c.
It is a well-balanced material with toughness greater than Zen/cII.

Similar to silicon compound-modified polypropylene, maleic anhydride-modified polypropylene containing maleic anhydride residues that have an affinity for liquid crystal resins (maleic acid residue base 10.8
The composition of Comparative Example C in which melt flow rate (% by weight, melt flow rate) 12 g/10 min) was replaced with silicon compound-modified polypropylene,
No improvement in impact strength was observed.

Furthermore, as can be seen from Table 2, it is clear that the thermal deformation temperature and elastic modulus can be reinforced without significantly impairing the impact strength.

8 and D It was manufactured and evaluated in the same manner as in Example 2, except that component (A) was replaced with polyethylene and component (B) was replaced with silicon compound-modified polyethylene. As a result, the heat distortion temperature was 110 ° C., and the elastic modulus was 16.8
00ky/cm", impact strength 48ky/c-/em
was gotten. For comparison, the same composition as Comparative Example B was evaluated, except that component (A> was replaced with polyethylene). As a result,
Elastic modulus 16,900J+/cm2, impact strength 20kg
・It was em/cm.

〔Effect of the invention〕

Since the composition of the present invention is constructed as described above, it is possible to obtain a polyolefin resin composition with improved performance, which has significantly improved rigidity (modulus of elasticity) and heat resistance (heat distortion temperature), and does not significantly impair impact strength. can be provided. This harmony of various performances makes it suitable as a molding material for mechanical parts.

Claims (1)

[Claims] A polyolefin resin composition comprising the following components: Component (A): 50 to 95% by weight of polyolefin resin
and component (B): a silicon compound represented by the general formula -SiR_nY_3_-_n (where R is an aliphatic hydrocarbon group, Y is a hydrolyzable organic group or hydroxyl group, and n is 0, 1 or 2) Component (C): Resin 2 to 4 capable of forming an anisotropic melt phase to 100 parts by weight of a mixture consisting of 50 to 5% by weight of a modified polyolefin containing residues.
0 parts by weight.