JP3165481B2 - Polyethylene resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant polyethylene resin composition which is made flame-retardant without using a halogen compound, and more specifically, has excellent flame retardancy, rigidity and impact resistance. The present invention relates to a polyethylene resin composition having mechanical properties and which can be effectively used in the fields of civil engineering and construction, furniture, electric wires, automobiles, and the like.

[0002]

2. Description of the Related Art As a means for making polyethylene flame-retardant, a method of blending a halogen-based compound as a flame retardant is known. However, in this method, mold corrosion occurs during polyethylene molding. There is a problem that toxic gas is generated in the human body when the polyethylene burns. Further, as a means of making polyethylene flame-retardant without using a halogen-based compound, a method of blending polyethylene with a large amount of a hydrated metal compound such as aluminum hydroxide or magnesium hydroxide is known. However, this method has a disadvantage that the impact resistance of the resin is impaired.

[0003] On the other hand, in order to solve the problems when a hydrated metal compound is blended with polyethylene, it has been proposed to blend red phosphorus with polyethylene together with the hydrated metal compound (Japanese Patent Laid-Open No. 50-148447). No.). However, although this method can reduce the amount of the hydrated metal compound required to obtain flame retardancy, it has a disadvantage that the resulting resin has a large decrease in impact resistance. The present invention has been made in view of the above circumstances, and is excellent in rigidity, impact resistance, and flame retardancy, causes mold corrosion during molding, and generates toxic gas to the human body during combustion. It is an object of the present invention to provide a polyethylene resin composition that does not cause any problems.

[0004]

Means and Action for Solving the Problems The present inventors have
In order to achieve the above objectives, flame retardancy is imparted to polyethylene without adding a halogen-based flame retardant, and its mechanical properties such as rigidity and impact resistance are improved, and mold release and moldability are improved. As a result of diligent studies on the fact that the above-mentioned object is effectively achieved when a specific amount of a phosphoric acid ester and red phosphorus are blended together with a specific amount of a hydrated metal compound in polyethylene, the present invention has been found. I've reached the point.

Accordingly, the present invention provides the following components (A),
Provided is a polyethylene resin composition containing (B), (C) and (D). (A) 100 parts by weight of polyethylene having a melt index measured in accordance with JIS-K7210 in the range of 0.01 to 6 g / 10 minutes (B) 30 to 120 parts by weight of a hydrated metal compound (C) Phosphate ester 0 2 to 10 parts by weight (D) 0.2 to 10 parts by weight of red phosphorus

Hereinafter, the present invention will be described in more detail. The polyethylene resin composition of the present invention is described below in (A) to (A).
The (D) component is blended. (A) Polyethylene The type and properties of polyethylene used in the present invention are not particularly limited, but MI (melt index) is 0.01 to 6 g.
/ 10 minutes, particularly preferably 0.02 to 2 g / 10 minutes. If the MI is less than 0.01 g / 10 min, the extrudability may deteriorate, and if the MI is more than 6 g / 10 min, the rigidity,
The impact resistance may be reduced, and the hollow moldability and the extrusion moldability may be deteriorated. The density of polyethylene is 0.94
0 to 0.969 g / cm ³ , especially 0.945 to 0.96
It is preferably 5 g / cm ³ . 0.940 density
If it is less than g / cm ³ , the rigidity may decrease,
If it exceeds 0.969 g / cm ³ , the impact resistance may decrease. MI is a value measured under the conditions of 190 ° C. and a load of 2.16 kg according to JIS-K7210, and density is a value measured under the conditions of 120 ° C. and 1 hour of annealing according to JIS-K7112.

(B) Hydrated Metal Compound The type of hydrated metal compound is not particularly limited.
One or more inorganic compounds having a hydroxyl group or water of crystallization such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, basic magnesium carbonate, and calcium aluminate hydrate can be suitably used. Among these, aluminum hydroxide is particularly preferred from the viewpoint of improving flame retardancy. The hydrated metal compound preferably has an average particle size of 10 μm or less, particularly preferably 0.1 to 5 μm. If the average particle size exceeds 10 μm, the impact resistance may decrease. The compounding amount of the hydrated metal compound is 30 to 120 parts by weight, preferably 40 to 100 parts by weight, based on 100 parts by weight of polyethylene. If the amount is less than 30 parts by weight, the flame retardancy becomes insufficient, and if it exceeds 120 parts by weight, the impact resistance is reduced.

[0008](C) phosphate ester  The phosphate ester is not particularly limited,
Butyl phosphate and the like. In addition, the molecular weight is 20
0 to 400 and a phosphorus content of 6 to 15% are preferably used.
Can be used. Such molecular weight and phosphorus content
As the phosphoric acid ester having, for example, triphenyl
Phosphate, tricresyl phosphate, cresyl di
Phenyl phosphate, octyl diphenyl phosphate
Tributoxyethyl phosphate, tributyl phosphate
Fate and the like. The amount of phosphate ester
0.2 to 10 parts by weight based on 100 parts by weight of polyethylene
Parts, preferably 0.5 to 5 parts by weight. 0.2 parts by weight
If less than 10 parts by weight, the effect of improving the impact resistance becomes insufficient.
If it exceeds, rigidity and heat resistance will decrease, and productivity will decrease.
You.

(D) Red Phosphorus Red phosphorus is not particularly limited, but red phosphorus which has been coated with an inorganic substance such as a titanium-based or aluminum-based substance can be preferably used. As red phosphorus, those having an average particle diameter of 20 μm or less are suitable. If the average particle size exceeds 20 μm, the impact resistance may decrease. The amount of red phosphorus is 0.2 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of polyethylene. If the amount is less than 0.2 part by weight, the effect of improving the flame retardancy is insufficient, and if it exceeds 10 parts by weight, the impact resistance is reduced.

Optional Components In addition to the above components (A) to (D), other additives such as a weathering agent, a coloring agent, a filler, an antioxidant, and a lubricant may be added to the composition of the present invention, if necessary. can do. For example, inorganic fillers such as calcium carbonate, calcium sulfate, magnesium sulfate, barium sulfate, talc, mica, silica, asbestos, glass beads, glass flakes, quartz powder, metal powder, glass fiber, carbon fiber, metal fiber, metal whisker Reinforcing agents such as antioxidants, light stabilizers, heat stabilizers, release agents such as silicone oil and wax, additives such as lubricants, antistatic agents, coloring agents, and other thermoplastic resins and rubbers, An elastomer or the like can be added.

Production Method The production method of the composition of the present invention is not limited. For example, the components (A) to (D) and optional components may be prepared by using a ribbon blender,
Good production can be achieved by melt-kneading using a tumble mixer, Henschel mixer, oven roll, Banbury mixer, single screw extruder, twin screw extruder, single screw reciprocating screw kneader, or the like.

[0012]

EXAMPLES Next, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Examples 1 to 5 and Comparative Examples 1 to 5 Each component shown in Table 1 and 100 parts by weight of polyethylene were dry blended with 0.05 part by weight of an antioxidant (Irganox 1010 manufactured by Ciba Geigy) to form a biaxial mixture. Pellets were obtained by kneading using a kneader at a temperature of 200 ° C. and a rotor rotation speed of 700 rpm.

The following components were used in Table 1. (A) Polyethylene A1: MI = 0.26 g / 10 min, density = 0.964 g
/ Cm ³ (Idemitsu Polyethylene 520M manufactured by Idemitsu Petrochemical Co., Ltd.)
B) A2: MI = 0.04 g / 10 min, density = 0.960 g
/ Cm ³ (Idemitsu Petrochemical Co., Ltd. Idemitsu Polyethylene 630E
T) (B) Hydrated metal compound B1: Aluminum hydroxide (average particle size: 4 μm) (CL-303 manufactured by Sumitomo Chemical Co., Ltd.) B2: Magnesium hydroxide (average particle size: 1 μm or less) (Kyowa Chemical Industry Co., Ltd.) 5) Kisuma 5B)

(C) Phosphate ester C1: Triphenyl phosphate (molecular weight: 326, phosphorus content: 9.5%) (TPP manufactured by Daihachi Chemical Industry Co., Ltd.) (D) Red phosphorus: average particle size 20 μm, titanium coating Red phosphorus (Hishigard TP-10 manufactured by Nippon Chemical Industry Co., Ltd.) (E) Other compounding agents (optional components) E1: Light stabilizer (benzotriazole-based ultraviolet absorber) (Tinuvin 326 manufactured by Ciba Geigy) E2: Carbon black ( E3: Titanium oxide (average particle size: 0.2 μm) (R-TC30, manufactured by Tyoxide Group)

Next, the above composition was measured for tensile strength, tensile modulus, Izod impact strength, surface impact strength, and flame retardancy by the following methods. Table 2 shows the results. Tensile strength and tensile modulus were measured in accordance with JIS-K7113. However, the test piece was a JIS No. 2 dumbbell. Izod impact strength Measured according to JIS-K7110. However, the test temperatures were 23 ° C and -10 ° C. Surface impact strength Measured according to JIS-K7211. However, the test temperature was −15 ° C., the load was 2 kg, the hammer was 1/2 inch φ, and the anvil was 2 inch φ. A horizontal flame test was performed using a 1 / 8-inch flame-retardant US UL94 test piece. In this case, a blue flame of methane gas of 1 inch was brought into contact with the test piece for 30 seconds, the flame was removed from the test piece, and the after-flame time (second) was measured.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

As described above, the polyethylene resin composition of the present invention has good flame retardancy and excellent mechanical properties such as excellent impact resistance and rigidity. In addition, it has excellent moldability and mold releasability in hollow molding, extrusion molding, compression molding, injection molding, etc., and does not cause mold corrosion during molding and does not generate toxic gas when burned. . Therefore, the polyethylene resin composition of the present invention can be effectively used as a molding material in the fields of civil engineering and construction, the field of furniture, the field of electric wires (for chairs and troughs), the field of automobiles, and the like.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-275138 (JP, A) JP-A-63-165447 (JP, A) Sakura Yamada, "Plastics Compounding Agent-Basics and Applications", First Edition Second printing, Taiseisha Co., Ltd., July 10, 1967, p. 153-157 (58) Field surveyed (Int.Cl. ⁷ , DB name) C08L 23/00-23/36 C08K 3/02 C08K 3/22 C08K 5/521

Claims (3)

(57) [Claims] 1. A polyethylene resin composition comprising the following components (A), (B), (C) and (D). (A) 100 parts by weight of polyethylene having a melt index measured in accordance with JIS-K7210 in the range of 0.01 to 6 g / 10 minutes (B) 30 to 120 parts by weight of a hydrated metal compound (C) Phosphate ester 0 2 to 10 parts by weight (D) 0.2 to 10 parts by weight of red phosphorus 2. The polyethylene resin composition according to claim 1, wherein the hydrated metal compound (B) is aluminum hydroxide. 3. The phosphoric ester (C) having a molecular weight of 2
The polyethylene resin composition according to claim 1, wherein the polyethylene resin composition has a range of 00 to 400 and a phosphorus content of 6 to 15%.