JPS63241048A - Stabilized polyolefin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition improved in weathering resistance, by mixing a polyolefin with a specified hindered piperidine compound, a benzoate compound and a phosphorus compound each in a specified amount. CONSTITUTION:100pts.wt. polyolefin (A) (e.g., polyethylene or polypropylene) is mixed with 0.01-1pt.wt. hindered piperidine compound (B) of MW>=750, selected from among compounds of formulas I, II and III, etc. (wherein n is 2-20), 0.01-1pt.wt. hindered piperidine compound (C) of MW<=500, selected from among compounds of formulas IV, V and VI, etc. and 0.01-1pt.wt. phosphorus compound (E) selected from among compounds of formulas IX and X, etc. to obtain the purpose stabilized polyolefin composition. This composition can give a molding which can resist degradations such as cracking by light for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to stabilized polyolefin compositions, particularly those with improved weather resistance.

<Prior Art> Polyolefins have excellent mechanical properties and are very useful as molded products, films, fibers, etc., but they generally have the drawback of being easily degraded by light.

Therefore, polyolefin compositions containing benzophenone-based, benzotriazole-based, nickel chelate-based, or hindered amine-based compounds, alone or in combination, are known as weathering stabilizers for dishes in order to prevent deterioration caused by light ( JP-A-58-118286, JP-A-59-219858).

<Problem that the invention seeks to solve> But something like this? Polyolefin compositions still have insufficient weather resistance, and in recent years, polyolefins have been used with other polymers and inorganic fillers to improve mechanical properties and improve the performance and appearance of molded products. , pigments, etc. are increasingly being added, but weather resistance performance tends to deteriorate, especially when inorganic fillers and the like are added.

For this reason, the present inventors conducted an investigation to develop a polyolefin composition that has excellent weather resistance not only when it does not contain an inorganic filler, but also when it contains an inorganic filler. It was discovered that a polyolefin composition having extremely excellent weather resistance can be obtained by specifying a combination of weather resistance stabilizers and further blending a specific phosphorus compound, and has led to the present invention.

Means for Solving the Problem> The present invention provides the following methods: (A) 0.01 to 1 hindered piperidine compound having a molecular weight of 750 or more returned from the following (A-1) #(A-4) per 100 parts by weight of polyolefin;
Multiple parts (n is an integer of 2 to 20) (n is an integer of 2 to 20) (A-4) (B) Molecule 31500 selected from the following (B-1) to (B-4) The following hindered piperidine compounds 0.0
1 to 5 parts by weight (B-8) CC') 0.01 to 1 part by weight of a benzoate compound selected from the following (C-1) and (C-2) (D) The following (
0.0 phosphorus compound selected from D-1) to (D-5)
The present invention provides a polyolefin composition characterized by containing 1 to 1 parts by weight (D-1) (D-2) (D-4).

The polyolefin used in the present invention is a polymer whose main polymerization component is α-olefin such as ethylene, propylene, butene-1, hexene-1,4-methyl-pentene-1, etc. Examples include homopolymers of α-olefins, random copolymers and block copolymers composed of two or more α-olefins, and specifically, polyethylene, polypropylene, polybutene-1
, polyisobutyne, poly-8-methyl-butene-1, poly-4-methyl-pentene-1, ethylene-propylene copolymer, ethylene-butene-1 copolymer, propylene-44-methyl-pentene-1 copolymer Coalescence, propylene-
Examples include butene-1 copolymer, decene-1-4-methyl-pentene-1 copolymer, and ethylene-propylene-butene-1 copolymer.

Also included are copolymers of α-olefins and other unsaturated compounds. For example, polyunsaturated compounds such as conjugated dienes and non-conjugated dienes, acrylic acid, methacrylic acid, vinyl acetate, etc. are used as copolymerization components. These α
- Copolymers of olefins and other unsaturated compounds are acid-modified, for example, polymers graft-modified with α, β-unsaturated fatty acids, alicyclic carboxylic acids, or derivatives thereof. It also includes rubbery, fatty, and waxy polymers.

Furthermore, in the present invention, a mixture of these polyolefins with synthetic rubber and an inorganic filler can be used depending on the purpose. As the synthetic rubber that can be used in the present invention, ethylene-α-olefin copolymer rubber is preferred. The ethylene-α-olefin copolymer rubber is a copolymer rubber of ethylene and an α-olefin such as propylene, butene-1, hexene-1, etc., or a non-conjugated diene as a third component in an ethylene-propylene system. Examples include terpolymer rubber (hereinafter abbreviated as "EPDMJ") obtained by copolymerizing ethylidene norbornene, cyclopentadiene, etc. Among these, ethylene-propylene copolymer rubber or EPDM is preferred.

Inorganic fillers that can be used in the present invention include talc, mica, wollastonite, calcium carbonate, barium sulfate, magnesium carbonate, clay, alumina, silica, calcium sulfate, carbon am, glass m fiber, metal m fiber, Examples include silica sand, silica stone, carbon black, titanium oxide, magnesium hydroxide, asbestos, zeolite, molybdenum, diatomaceous earth, sericite, shirasu, calcium hydroxide, calcium sulfite, sodium sulfate, bentonite, and graphite.

Among these, talc, mica, calcium carbonate, glass fiber, wollastonite, etc. are preferable as those that improve low-temperature impact resistance, moldability, and paintability.

In particular, in order to obtain a polyolefin composition with improved low-temperature impact resistance, moldability, and paintability, 25 to 90 ffiffi% of crystalline polyolefin, 5 to 35% by weight of ethylene-α-olefin copolymer rubber, and Preferably, 5 to 40% by weight of inorganic filler is mixed.

The stabilizers used in the present invention include the above (A) to (D).
), but in the hindered piperidine compound (A) having a molecular weight of 750 or more, preferably A
-1, A-2, and in the hindered piperidine compound (B) with a molecule of 3500 or less, preferably B-1, B
-2, preferably C-1 in the benzoate compound (C), and D-1, D-2, and D-8 in the phosphorus compound (D).

In the present invention, the stabilizers (A), (B), (C), and (D) are all essential components, and the desired effect cannot be obtained without any of them. Moreover, each of the stabilizers shown in (A) to (D) can be used in combination in two or more dishes.

The amount of stabilizers of each group (A) to (D) used is 0.01 to 1 part by weight, preferably 0.05 to 0.5 part by weight, per 100 parts by weight of polyolefin.

Furthermore, various pigments can be added to the composition for coloring in order to improve the appearance and appearance of the molded article made of the composition of the present invention. As the pigment used in the present invention, inorganic pigments and organic pigments suitable for polyolefins can be used.

For example, titanium oxide, carbon black, yellow iron oxide, titanium yellow, Hansa yellow, benzine yellow, red iron oxide, permanent red, thioindigo red, thioindigo maroon, manganese purple, dioxazine violet, ultramarine blue, phthalocyanine blue, phthalocyanine green, isoindo Linon yellow, quinophthalon yellow
Examples include 1la azo yellow, perinone orange, quinacridone red, quinacridone scarlet, perylene red, perylene scarlet condensed azo red, dioxazine violet, indanthrone blue, syncasia red, carbon black, and titanium oxide. As pigment dispersants, metal soaps such as calcium stearate and magnesium stearate, and polyolefin waxes such as polyethylene wax and polypropylene wax are used. In order to enhance the dispersion effect of polyolefin wax, it is preferable to mix the pigment and wax in advance using a powder ball mill or the like before use.

Note that calcium stearate is effective as a stabilizer even when it does not contain a pigment, and is a component that is preferably added in an amount of 1 liffi part or less per 1 part of polyolefin 100 mff in addition to the stabilizer specified in the present invention. be.

In addition to the stabilizers specified in the present invention, antioxidants commonly used in polyolefins, such as phenolic and thioether antioxidants, may also be used.

Such phenolic antioxidants include, for example, 2
．． 6-di-t-butyl-4-methylphenol, n-tadecyl-8(8',5'-di-t-butyl-4'-
hydroxyphenyl)-propionate, tetrakis-
[Methylene-8-(8',5'-di-t-butyl-4'
-hydroxyphenyl)propionate-co-methane, 1
,8゜5-tris(4-t-butyl-8-hydroxy-
2,6-dimethylbenzyl)isocyanurate, 8.9
-bisC2-(8-(8-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy)-to
1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane and tris(8,5-
Examples of thioether compounds include dilauryl-8,8'-thiodipropionate, ditridecyl-8,8'-thiodipropionate,
Simiristyl-8,8'-thiodipropionate, distearyl-8,8'-thiodipropionate, pentaerythritol-tetrakis-(β-lauryl-thiopropionate) and 8,9-bis(dodecylthioethyl )-2,4,8,10-tetraoxaspiro [5.5]
Examples include undecane.

However, even with these antioxidants, it is preferable not to use them in combination with thioether compounds because they tend to impair weather resistance. Even when used in combination, the following stabilizers specified in the present invention are It is necessary to.

The polyolefin composition of the shrub invention may contain other additives, such as processing oils, plasticizers, etc., as long as they do not impair its properties.
It may contain a lubricating oil, a lubricant, a nucleating agent, an antistatic agent, a mold release agent, a fungicide, and the like.

Incorporation of the various stabilizers and additives mentioned above into polyolefin is as follows:
- This can be easily carried out by kneading in a heated molten state using a conventional mixing machine such as a screw extruder, twin screw extruder, Banbury mixer, roll, Brabender, or kneader.

<Example> The present invention will be explained below with reference to Examples.

Examples 1 to 21, Comparative Examples 1 to 9 Powdered propylene-ethylene copolymer (ethylene content 8.0% by weight, melt index 2.8F/10 minutes)
Add 0.05 parts by weight of calcium stearate and the test additives listed in Table 1 (the amount added is listed in parts by weight in Table 1) to 100 parts by weight, mix with a Henschel mixer,
The pellets were extruded at 230°C using an 80M extruder.

This pellet was molded using a 5.5 oz injection molding machine.
Create a sheet of 60w x 601ff with thickness IH at ℃,
This was used as a test piece for weather resistance tests.

The weathering test was carried out in a Sunshine Weathermeter (black panel 88°C1 water spray - 18 minutes/120 minutes). Weather resistance was evaluated based on the time until cracks appeared on the surface of the test piece, and the results are shown in Table 1.

Among the symbols of the test additives in Table 1, 8-1 to A-4
, B-1 to B-4, C-1, C-2 and D-1 to D
-5 is the compound described above as an additive used in the present invention, and A-1, A-2 and A-8 are repeating units n
A mixture of 2 to 10 was used. Other symbols are as follows.

(n is an integer of 2 to 20) Tinuvin 622LD: V-8 AO-2 Tetrakis-[Methylene-8-(8') manufactured by Chill Geigy.

5'-di-t-butyl-4'-hydroxyphenyl)propionate coumethane AO-8) lis(8,5-di-t-butyl-4-hydroxybenzyl)isocyanurate AO-41,8,5- Tris(4-t-butyl-8-hydroxy-2,6-dimethylpenzyl)isocyanurate AO-58,9-bisl:2-(8-(8-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy)-1,1-dimethylethyl)-2,4,8,
10-tetraoxaspiro[5.5]undecane AO-6 pentaerythritol-tetrakis-(β-lauryl-thiopropionate) AO-7 simiristyl-
8,8-thiodipropionate AO-8 distearyl-8,8-monothiodipropionate Examples 22-41, Comparative Examples 10-18 6. Of/10 minutes) 100 parts by weight, 20 parts by weight of talc with an average particle size of 1.5μ as a filler, 0.5 parts by weight of carbon black as a pigment, and 0.0 parts by weight of calcium stearate.
5 parts by weight and the test additives listed in Table 2 (the amounts added are listed in Table 2 in parts by weight) were added, and the above Examples 1 to 21
It was extruded and injection molded in the same manner as above and subjected to a weather resistance test.

The conditions of the weathering test were the same as in Examples 1 to 21, and the results are shown in Table 2. Further, the symbols of the test additives in Table 2 are the same as in Table 1.

<Effects of the Invention> As described above, the polyolefin composition of the present invention has extremely excellent weather resistance not found in conventional products, and its industrial utility value is extremely high.

Claims (1)

[Claims] (1) Per 100 parts by weight of polyolefin (A) 0.01 to 1 hindered piperidine compound with a molecular weight of 750 or more selected from the following (A-1) to (A-4)
Part by weight ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (A-1) (n is an integer from 2 to 20) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (A-2) (n is an integer from 2 to 20) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(A-3) (n is an integer from 2 to 20) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(A-4) (B) Below ( Hindered piperidine compound with a molecular weight of 500 or less selected from B-1) to (B-4) 0.01 to 1
Part by weight ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (B-1) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (B-2) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (B-3) ▲ Mathematical formulas, Chemical formulas, tables, etc. are available ▼ (B-4) (C) 0.01 to 1 part by weight of benzoate compounds selected from the following (C-1) and (C-2) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (C-1) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (C-2) (D) 0.01 to 1 part by weight of a phosphorus compound selected from the following (D-1) to (D-5) ▲ Mathematical formula , chemical formulas, tables, etc. ▼ (D-1) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (D-2) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (D-3) ▲ Mathematical formulas, chemical formulas, tables, etc. ▼ (D-4) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (D-5) A polyolefin composition characterized by containing the following.