JP2007100110A - Flame-retardant and abrasion-resistant ethylenic resin composition and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an ethylenic resin composition having high flame retardance and abrasion resistance, good processability and other characteristics and especially remarkably excellent mechanical characteristics as compared with those of conventional compositions and suitable for automotive electric wire coverings, etc. <P>SOLUTION: This flame-retardant and abrasion-resistant ethylenic resin composition is obtained by compounding 100 pts.wt. of a resin component with 65-150 pts.wt. of an inorganic flame retardant (C) and mixing and kneading the resultant mixture in the absence of a cross-linking agent. The resin component is composed of 100 pts.wt. of a substantially linear ethylene-α-olefin copolymer (A) having 0.1-5 g/10 min melt flow rate, 0.900-0.930 g/cm<SP>3</SP>density and ≤3.0 ratio (Mw/Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) and produced by using a single-site catalyst and 15-100 pts.wt. of a linear ethylene-α-olefin copolymer (B) having 0.1-5 g/10 min melt flow rate and 0.931-0.950 g/cm<SP>3</SP>density. Furthermore, the method for producing the composition is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a flame-retardant and abrasion-resistant ethylene-based resin composition and a method for producing the same, and more specifically, is excellent in flame retardancy, heat resistance and wear resistance, and has higher mechanical properties than conventional ones. The present invention relates to a flame-retardant and wear-resistant ethylene-based resin composition that has excellent, low-temperature characteristics, insulating properties, workability, oil resistance, and flexibility, and that can be suitably used for automotive wire coating and the like, and a method for producing the same. .

  2. Description of the Related Art In recent years, automobiles have become more and more electronic, and in-car wiring for transmitting power and control signals for driving various electrical components has increased, and the number of electric wires used for this has increased. These electric wires have been reduced in weight and thickness in order to improve fuel efficiency and increase space in the vehicle to improve comfort. On the other hand, these electric wires may be worn by friction between the electric wires or the electric wires and other automobile parts due to vibrations of the engine, the vehicle body, etc., and wear resistance is required. In addition, since the above electric wires are used under conditions such as high temperature, cold, wind and rain, and high humidity, heat resistance, low temperature characteristics, flame retardancy, moisture resistance, and the like are required. Furthermore, since these electric wires are in contact with automobile lubricating oil, gasoline, grease, hydraulic oil, etc., oil resistance is required.

  Polyvinyl chloride resin composition (hereinafter referred to as PVC compound), which has been particularly advantageous in terms of physical properties, cost, workability, wire harness assembly workability, etc. Have been used). However, a PVC compound is blended with a plasticizer to impart heat resistance, weather resistance, flexibility, workability, etc., which may bleed on the resin surface, and the surface of the wire is sticky, The texture may be deteriorated or may be shifted to a part made of another resin in contact with the resin, and problems may occur in oil resistance, printability, etc., and improvement has been demanded. In addition, automotive wires coated with PVC compounds generate a lot of smoke, generate harmful gases, or produce a large amount of alkaline incineration ash when incinerated or incinerated for disposal. There were problems such as occurrence. Moreover, it is very difficult to take out a coating layer from an automobile electric wire coated with a PVC compound and to recycle it.

  In order to solve the above-mentioned problems of PVC compounds used for automobile electric wires, the present applicant has two types of different linear ethylene-α-olefin copolymers having specific physical properties and specific flame retardants. And a patent application was filed (see Japanese Patent Application Laid-Open No. 6-20089). Although this flame retardant ethylene resin composition has achieved its purpose to some extent, the mechanical properties have not yet been sufficiently satisfied due to the addition of a large amount of flame retardant to the ethylene resin.

  The present invention improves the drawbacks of the above-described PVC compound or flame retardant ethylene resin composition and is excellent in flame retardancy, heat resistance, abrasion resistance, insulation, low temperature characteristics, oil resistance, flexibility, etc. A flame-retardant and wear-resistant ethylene-based resin composition that is superior in mechanical properties, has good workability, has no harmful gas or alkaline incineration ash during incineration, and can be easily recycled. A manufacturing method is an issue.

As a result of intensive studies to solve the above problems, the present inventor is excellent in flame retardancy, heat resistance, wear resistance, etc. by adopting the following composition and its production method, compared with the conventional one. Excellent mechanical properties, low-temperature properties, insulation, workability, oil resistance, and flexibility are also good, and a flame-retardant and wear-resistant ethylene-based resin composition that can be suitably used for automotive wire coating, etc. is obtained. As a result, the present invention has been completed.
That is, according to the first aspect of the present invention, the melt flow rate is 0.1 to 5 g / 10 min, the density is 0.900 to 0.930 g / cm ^{3, the} weight average molecular weight (Mw) and the number average molecular weight (Mn). A substantially linear ethylene-α-olefin copolymer (A) produced using a single site catalyst with a ratio (Mw / Mn) of 3.0 or less, and a melt 100 parts by weight of a resin component comprising 15 to 100 parts by weight of a linear ethylene-α-olefin copolymer (B) having a flow rate of 0.1 to 5 g / 10 min and a density of 0.931 to 0.950 g / cm ³ A flame-retardant and wear-resistant ethylene-based resin composition is provided in which 65 to 150 parts by weight of an inorganic flame retardant (C) is blended in a part and mixed and kneaded in the absence of a crosslinking agent.
Further, according to the second invention of the present invention, in the first invention, the α-olefin of the ethylene-α-olefin copolymer (A) is octene-1. A wearable ethylene-based resin composition is provided.
On the other hand, according to the third aspect of the present invention, the melt flow rate is 0.1 to 5 g / 10 min, the density is 0.900 to 0.930 g / cm ^{3, the} weight average molecular weight (Mw) and the number average molecular weight (Mn). A substantially linear ethylene-α-olefin copolymer (A) produced using a single site catalyst with a ratio (Mw / Mn) of 3.0 or less, and a melt 100 parts by weight of a resin component comprising 15 to 100 parts by weight of a linear ethylene-α-olefin copolymer (B) having a flow rate of 0.1 to 5 g / 10 min and a density of 0.931 to 0.950 g / cm ³ Provided with 65 to 150 parts by weight of an inorganic flame retardant (C) in a part and mixed and kneaded in the absence of a crosslinking agent to provide a method for producing a flame-retardant and wear-resistant ethylene-based resin composition Is done.
According to a fourth aspect of the present invention, in the third aspect, the α-olefin of the ethylene-α-olefin copolymer (A) is octene-1. A method for producing a wearable ethylene-based resin composition is provided.

The flame-retardant and abrasion-resistant ethylene-based resin composition of the present invention has excellent mechanical properties because the main component ethylene-based resin has a narrow molecular weight distribution, and has a main chain. Since a certain amount of long-chain branching is included, the processability is excellent and the density is classified as low density, so that a large amount of flame retardant can be uniformly dispersed and retained. Moreover, since the medium density linear ethylene-α-olefin copolymer is blended as the other main component, it is excellent in wear resistance and the like. In addition, since an inorganic flame retardant is used, no harmful gas is generated during incineration.
Therefore, the flame-retardant and abrasion-resistant ethylene-based resin composition of the present invention is excellent in various properties such as flame retardancy, abrasion resistance, heat resistance, insulation, workability, low temperature characteristics, oil resistance, and flexibility. At the same time, there is little environmental pollution during incineration, and the mechanical properties are significantly improved compared to conventional compositions. A flame-retardant and abrasion-resistant ethylene-based resin composition having such excellent characteristics, particularly excellent processability and mechanical characteristics, is a very suitable material for coating electric wires for automobiles and the like.

  The ethylene-α-olefin copolymer (A) used in the present invention is a base material of the composition of the present invention, and is a copolymer of ethylene and an α-olefin such as an α-olefin having 3 to 12 carbon atoms. It is a polymer. Specific examples of the α-olefin include propylene, butene-1, hexene-1, 4-methylpentene-1, octene-1, decene-1, dodecene-1, and the like. Among these, octene-1 is particularly preferable from the viewpoints of mechanical properties and workability of the flame-retardant and wear-resistant ethylene-based resin composition.

The ethylene-α-olefin copolymer (A) has the following physical properties: melt flow rate 0.1 to 5 g / 10 min, density 0.900 to 0.930 g / cm ^3, and weight average molecular weight (Mw) and number. It has a ratio (Mw / Mn) of 3.0 or less with respect to the average molecular weight (Mn). Here, the melt flow rate is measured in accordance with JIS K7210, and if it is less than 0.1 g / 10 minutes, the workability is inferior, and if it exceeds 5 g / 10 minutes, the mechanical properties and wear resistance are inferior. Absent. The density is measured in accordance with JIS K7112, the abrasion resistance is less than 0.900 g / cm ^3, heat resistance, poor oil resistance, exceeds 0.930 g / cm ^3, flexibility, elongation The processability is inferior, and the flame retardant cannot be uniformly dispersed and retained in the resin component, which is undesirable. The density range of the resin component (A) is generally classified as low density. Furthermore, the ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) is measured by size exclusion chromatography and should be 3.0 or less, preferably 2.5. It is as follows. If Mw / Mn exceeds 3.0, the mechanical properties are inferior. This Mw / Mn is a value that serves as an index of molecular weight distribution. The smaller the Mw / Mn, the smaller the molecular weight distribution.

  In the present invention, the single-site catalyst used in the production of the ethylene-α-olefin copolymer (A) has the same active site (single site) and has a high polymerization activity with respect to ethylene. It is. This single-site catalyst is also called a metallocene catalyst and also a Kaminsky catalyst from the inventor's name. The catalyst used in the present invention is a further improvement of this, for example, a catalyst having an appropriately constrained geometry (Constrained Geometry Catalysts), which is a metal atom of Groups 3 to 10 of the periodic table or lanthanoid (lanthanum series). And a metal coordination complex containing a delocalized π (pi) bond substituted with an atomic group that induces restraint is preferable. A preferred catalyst complex is:

(Wherein M is a metal atom of Group 3-10 of the periodic table or a lanthanoid, Cp * is a cyclopentadienyl group or a substituted cyclopentadienyl group bonded to M in an η ⁵ bond mode, Z is boron or an element of group 14 of the periodic table, and optionally an atomic group containing a sulfur atom or an oxygen atom, the atomic group having up to 20 atoms other than hydrogen atoms, or Cp * And Z together form a fused ring system, X is independently an anionic ligand or a neutral Lewis base ligand having up to 30 atoms other than hydrogen atoms, and n is 0 , 1, 2, 3 or 4 and 2 less than the valence of M, and Y is an anionic or non-anionic ligand bonded to Z and M, a nitrogen atom, a phosphorus atom Containing oxygen or sulfur atoms De is, and whether having atoms other than hydrogen atoms up to 20, or Y and Z optionally is represented by the form a fused ring system) together.

Specific examples of the catalyst complex include (tertiary butylamide) (tetramethyl-η ⁵ -cyclopentadienyl) -1,2-ethanediylzirconium dichloride, (tertiary butylamide) (tetramethyl-η ^5- Cyclopentadienyl) -1,2-ethanediyltitanium dichloride, (methylamide) (tetramethyl-η ⁵ -cyclopentadienyl) -1,2-ethanediylzirconium dichloride, (methylamide) (tetramethyl-η ^5- Cyclopentadienyl) -1,2-ethanediyltitanium dichloride, (ethylamide) (tetramethyl-η ⁵ -cyclopentadienyl) methylenetitanium dichloride, (tert-butylamido) dibenzyl (tetramethyl-η ⁵ -cyclopentadi) Enyl) silane zirconium dibenzyl, Jiruamido) dimethyl (tetramethyl-eta ⁵ - cyclopentadienyl) silane titanium dichloride, (phenyl phosphide) dimethyl (tetramethyl- eta ⁵ - cyclopentadienyl) silane zirconium dibenzyl, (tert-butylamido) dimethyl (tetramethyl A methyl- (eta) ⁵ -cyclopentadienyl) silane titanium dimethyl etc. are illustrated.

  The catalyst further contains an activated cocatalyst. As the cocatalyst, an aluminoxane having a high polymerization degree or a low polymerization degree, particularly methylaluminoxane is suitable. So-called modified methylaluminoxane is also suitable for use as the cocatalyst.

  The polymerization of the ethylene-α-olefin copolymer (A) in the present invention is preferably carried out by a solution polymerization method, and the conditions for a normal solution polymerization method can be employed as they are. That is, the polymerization temperature is 0 to 250 ° C., and the polymerization pressure is from normal pressure to 100 MPa. If necessary, the polymerization can be carried out according to a suspension method, a slurry method, a gas phase method or other methods. A support can be used, but preferably the catalyst is used in a homogeneous (eg, soluble) state. Of course, an active catalyst system is formed in the reactor when the catalyst component and its cocatalyst component are added directly to the polymerization process and a suitable solvent or diluent (including concentrated monomer) is used in the polymerization process. It is preferable. However, the active catalyst may be formed in a separate step in a suitable solvent prior to adding it to the polymerization mixture, and this method is also preferred. The details of the method for producing the ethylene-α-olefin copolymer (A) are described in JP-A-6-306121, JP-A-7-5000062, and the like.

  Another base material used in the present invention, a linear ethylene-α-olefin copolymer (B), is a copolymer of ethylene and an α-olefin such as an α-olefin having 3 to 12 carbon atoms. It is a coalescence. Specific examples of the α-olefin include propylene, butene-1, hexene-1, 4-methylpentene-1, octene-1, decene-1, dodecene-1, and the like.

The linear ethylene-α-olefin copolymer (B) has the following physical properties: melt flow rate of 0.1 to 5 g / 10 min and density of 0.931 to 0.950 g / cm ³ . Here, the melt flow rate is measured in accordance with JIS K7210, and if it is less than 0.1 g / 10 minutes, the workability is inferior, and if it exceeds 5 g / 10 minutes, the mechanical properties and wear resistance are inferior. Absent. The density is measured in accordance with JIS K7112, and if it is less than 0.931 g / cm ³ , the heat resistance, wear resistance, and oil resistance are inferior, and if it exceeds 0.950 g / cm ³ , The flexibility and elongation are inferior, and the flame retardant cannot be uniformly dispersed and retained in the resin component, which is undesirable. In addition, the said density range of the resin component (B) is generally classified into medium density.

  The catalyst used for the production of the linear ethylene-α-olefin copolymer (B) in the present invention is not particularly limited, and may be the single-site catalyst, and other conventionally commonly used catalysts. The catalyst may be used. One of the common catalysts is called a Ziegler catalyst, a main catalyst made of a transition metal compound such as a titanium compound or a vanadium compound, a co-catalyst made of an organometallic compound such as organoaluminum, and silicon, titanium, magnesium, etc. It is a catalyst comprised from the catalyst support | carrier which consists of oxide or chloride of this. In addition, there is a catalyst called a Philips catalyst, which is composed of a main catalyst made of chromium oxide and a catalyst carrier made of an oxide such as silicon or aluminum. Furthermore, there is a catalyst composed of a main catalyst made of molybdenum oxide, called a standard catalyst, and a catalyst carrier made of an oxide of aluminum.

  For the polymerization of the linear ethylene-α-olefin copolymer (B), methods such as a solution polymerization method, a suspension polymerization method, and a gas phase polymerization method can be used. In general, the temperature during polymerization is 0 to 250 ° C., and the pressure is high pressure (50 MPa or more), medium pressure (10 to 50 MPa), or low pressure (normal pressure to 10 MPa).

  The amount of the linear ethylene-α-olefin copolymer (B) is 15 to 100 parts by weight with respect to 100 parts by weight of the ethylene-α-olefin copolymer (A). If the blending amount is less than 15 parts by weight, the abrasion resistance, heat resistance and oil resistance are inferior and undesirable. On the other hand, if it exceeds 100 parts by weight, processability, flexibility, elongation and the like are inferior, and it is difficult in the resin component. This is undesirable because the flame retardant cannot be uniformly dispersed and retained.

  Examples of the inorganic flame retardant (C) used in the present invention include huntite, hydromagnesite, antimony trioxide, aluminum hydroxide, magnesium hydroxide, potassium hydroxide, calcium hydroxide, calcium phosphate, zircon oxide, titanium oxide, Zinc oxide, magnesium oxide, magnesium carbonate, calcium carbonate, barium sulfate, barium borate, barium metaborate, zinc borate, zinc metaborate, anhydrous alumina, molybdenum disulfide, clay, red phosphorus, diatomaceous earth, kaolinite, montmorillonite , Hydrotalcite, talc, silica, white carbon, zeolite, asbestos, lithopone and the like. When using these inorganic flame retardants, the surface of the flame retardant is a fatty acid or metal salt such as stearic acid, oleic acid, palmitic acid, paraffin, wax, or a modified product thereof, organic silane, organic borane, organic titanate, etc. It is preferable to carry out a surface treatment such as coating with.

  The blending amount of the flame retardant is 65 to 150 with respect to 100 parts by weight of a resin component [total amount of ethylene-α-olefin copolymer (A) and linear ethylene-α-olefin copolymer (B)]. Parts by weight. This is because when the blending amount of the flame retardant is less than 65 parts by weight, the flame retardancy is insufficient. On the other hand, when it exceeds 150 parts by weight, not only the workability is deteriorated but also the mechanical properties and abrasion resistance of the molded product. By deteriorating properties, low temperature characteristics, flexibility and the like.

  Various additives and auxiliary materials can be blended in the flame-retardant and abrasion-resistant ethylene-based resin composition of the present invention within a range not impairing the characteristics of the present invention, depending on the purpose of use. These various additives and auxiliary materials include stabilizers, antioxidants, UV absorbers, light stabilizers, antistatic agents, lubricants, processability improvers, fillers, dispersants, copper damage inhibitors, and neutralizers. , Foaming agents, anti-bubble agents, colorants, carbon black and the like.

  The flame-retardant and abrasion-resistant ethylene-based resin composition of the present invention is blended with appropriate amounts of the above-mentioned various additives and auxiliary materials as necessary in the above-mentioned components (A), (B) and (C). In addition, it can be produced by uniformly mixing and kneading using a general method such as a kneader, a Banbury mixer, a continuous mixer or an extruder.

  Some ethylene-α-olefin copolymers (A) used in the present invention are sold as Affinity (registered trademark) by The Dow Chemical Company. The resin is produced using a geometrically constrained catalyst that is a kind of single-site catalyst, and is added to the main chain of the ethylene-α-olefin copolymer in an amount of 0.01 to 1,000 carbon atoms per 1000 carbon atoms in the main chain. Contains 3 long-chain branches in a ratio of 3. Since this long-chain branching is contained, the processability is good even though Mw / Mn is small, that is, the molecular weight distribution is small. A small molecular weight distribution means excellent mechanical properties. Conventionally, in an ethylene-α-olefin copolymer, a small molecular weight distribution, that is, excellent mechanical properties and good processability have not been compatible, but the resin component (A) in the present invention has mechanical properties. By selecting a low-density one that is excellent in both processability, even a large amount of flame retardant can be uniformly dispersed and retained in the ethylene-α-olefin copolymer. is there. Moreover, the medium density linear ethylene-α-olefin copolymer (B) in the present invention imparts excellent wear resistance and the like. Furthermore, the inorganic flame retardant (C) is used as a flame retardant in the composition of the present invention, and no harmful gas is generated during incineration.

  EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these Examples.

The physical properties and the measurement conditions are as follows.
(1) Tensile strength / elongation: A dumbbell-shaped No. 3 test piece (thickness 1 mm) defined in 3.2.2 of JIS K6301 is used according to JIS C3005K, item 18, and the tensile speed is 200 mm / min. .
(2) Oxygen index: In accordance with JIS K7201, the test piece is A-1.
(3) Abrasion resistance: Performed in accordance with JASO D611 11.2 blade reciprocation method. The coating thickness of the insulator is 0.3 mm, and the load is 5N and 7N.
(4) Heat resistance: In accordance with 25 of JIS C3005, the test piece is a sheet specified in 25.1.1 (3) and tested at a test temperature of 120 ° C.
(5) Low temperature embrittlement resistance: Performed according to JIS K7216.
(6) Oil resistance: In accordance with JIS K7114, the test piece is a No. 3 test piece specified in 3.2.2 of JIS K6301, and the immersion reagent is the one specified in item 6 of JASO D611. After measuring various rates of change, a tensile test is performed to calculate the tensile strength / residual rate of elongation.
(7) Flexibility (1% modulus): Performed according to JIS K6301.

Example 1
The composition shown in Table 1 is kneaded at 180 ° C. for 10 minutes with a Banbury mixer, and then granulated to obtain pellets. Using the pellets thus produced, the following physical properties are measured using a sheet obtained by molding for 3 minutes at 160 ° C. and 150 kg / cm ² using a hot press molding machine. The results are also summarized in Table 1.

(Examples 2 and 3, Comparative Examples 1 to 8)
Using the composition shown in Table 1, the same operation as in Example 1 is repeated. The results of each physical property evaluation are also summarized in Table 1.

  From the results shown in Table 1, the following is clear. First, all the examples of the present invention are excellent in all measured physical properties, but Comparative Examples 1 to 8 are inferior in one or more physical properties. This is different from the resin component or composition used in the present invention in Comparative Examples 1 to 6, and Comparative Examples 7 and 8, although the resin component and composition are the same as those used in the present invention, This is because the blending amount of the flame retardant is different from that of the present invention.

Claims (4)

With a melt flow rate of 0.1 to 5 g / 10 min, a density of 0.900 to 0.930 g / cm ³ and a ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn) of 3.0 or less 100 parts by weight of a substantially linear ethylene-α-olefin copolymer (A) produced using a single site catalyst, a melt flow rate of 0.1 to 5 g / 10 min and a density of 0 Inorganic flame retardant (C) 65-150 to 100 parts by weight of resin component consisting of 15-100 parts by weight of linear ethylene-α-olefin copolymer (B) of 931-0.950 g / cm ³ A flame-retardant and abrasion-resistant ethylene-based resin composition, which is blended with parts by weight and mixed and kneaded in the absence of a crosslinking agent.   The flame retardant wear-resistant ethylene-based resin composition according to claim 1, wherein the α-olefin of the ethylene-α-olefin copolymer (A) is octene-1. With a melt flow rate of 0.1 to 5 g / 10 min, a density of 0.900 to 0.930 g / cm ³ and a ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn) of 3.0 or less 100 parts by weight of a substantially linear ethylene-α-olefin copolymer (A) produced using a single site catalyst, a melt flow rate of 0.1 to 5 g / 10 min and a density of 0 Inorganic flame retardant (C) 65-150 to 100 parts by weight of resin component consisting of 15-100 parts by weight of linear ethylene-α-olefin copolymer (B) of 931-0.950 g / cm ³ A method for producing a flame-retardant and wear-resistant ethylene-based resin composition, comprising mixing parts by weight and mixing and kneading in the absence of a crosslinking agent.   The method for producing a flame-retardant and wear-resistant ethylene-based resin composition according to claim 3, wherein the α-olefin of the ethylene-α-olefin copolymer (A) is octene-1.