JP2000251538A - Non-halogen incombustible resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide fire-resistance equal to that of polyvinyl chloride and eliminate the generation of toxic gas in incinerating treatment by adding magnesium hydroxide and a heat resisting antioxidant having a specified induction period to a polyolefin resin in a specified ratio to form a non-halogen incombustible resin composition. SOLUTION: To 100 pts.wt. of a polyolefin resin containing no halogen are added 10-250 pts.wt. of magnesium hydroxide revealing fire resistance in the decomposition by burning and 0.1-10 pts.wt. of a heat resisting antioxidant having an induction period θ at 200 deg.C of log θ>0 and suppressing the decomposition of the resin at about its burning temperature. By this mixing, the reduction in mechanical characteristic or insulating property and the blooming of the surface can be prevented, in addition to the imparting of fire resistance. As the resin, at least one of polypropylene, straight chain-like low density, super-low density, middle density or high density polyethylene, a copolymer of ethylene with vinyl acetate or ethyl acrylate and ethylene-propylene rubber is preferably used. This composition is useful for a wire coating material succeeding in at least one of various combustion tests.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition having the same flame retardancy as a polyvinyl chloride (PVC) composition and containing no halogen and capable of being incinerated.

[0002]

2. Description of the Related Art PVC compositions are widely used in wire coatings, tubes, tapes, packaging materials, building materials, etc. because of their good electrical insulation and self-extinguishing flame retardancy. Incidentally, since the PVC composition contains chlorine (Cl) which is a halogen, a corrosive gas such as HCl or a toxic gas such as dioxin is generated during combustion. Therefore, various PVC
There was a problem that when products became waste, they could not be incinerated. Therefore, at present, landfill disposal is performed. However, since a Pb-based stabilizer is used as an additive in the PVC composition, there is also a problem that this is eluted into soil and the like, and it is difficult to dispose of it as industrial waste. It has become to.

[0003]

On the other hand, PVC
If a halogen-free polyethylene (PE) or polypropylene (PP) is used as a resin composition instead of
Since no harmful gas is generated during combustion, incineration is possible. However, these halogen-free resin compositions are made of PVC.
There was a defect that the flame retardancy was inferior to that of For example, comparing the oxygen index (OI), which is one of the evaluation criteria for the flame retardancy of the resin composition, the OI of PVC is 23 to 40, whereas the OI of PE and PP is about 17 to 19. It turns out that it is inferior. Therefore, in order to impart flame retardancy to a halogen-free resin composition such as PE or PP, it is usually practiced to add a metal hydrate such as Mg (OH) ₂ or Al (OH) ₃ thereto. Have been done. However,
The desired high flame retardancy may not be obtained with the metal hydrate alone, or if a large amount of the metal hydrate is added to obtain the desired high flame retardancy, properties such as mechanical properties may be significantly deteriorated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resin composition having the same level of flame retardancy as PVC and generating no harmful gas during incineration.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to provide a heat-resistant resin having 10 to 250 parts by weight of magnesium hydroxide and an induction period at 200 ° C. of logθ> 0 based on 100 parts by weight of a polyolefin resin. The problem can be solved by a non-halogen flame-retardant resin composition containing an antioxidant in an amount of 0.1 to 10 parts by weight. The polyolefin resin, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene rubber, polypropylene, linear low-density polyethylene, ultra-low-density polyethylene, medium-density polyethylene, and high-density polyethylene It is preferable that it is composed of one or more selected from the group consisting of: When the non-halogen flame-retardant resin composition of the present invention is used as a coating material for electric wires, cables or similar products, it is established in the Electrical Appliance and Material Control Law, UL Standard, IEEE Standard 383, and IEC Standard 332-1. It can pass one or more of the burning tests that have been performed.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The halogen-free flame-retardant resin composition of the present invention (hereinafter referred to as a non-halogen flame-retardant resin composition) is obtained by adding a metal hydrate as a flame retardant to a halogen-free polyolefin-based resin. By adding an antiaging agent, preferable high flame retardancy can be achieved.

The polyolefin resin used in the present invention includes ethylene-vinyl acetate copolymer (EVA),
Ethylene-ethyl acrylate copolymer (EEA), ethylene-propylene rubber (EPR), polypropylene (PP), linear low density polyethylene (LLDPE),
Very low density polyethylene (VLDPE), medium density polyethylene, and high density polyethylene are preferred. Especially EV
A and EEA have relatively high flame retardancy of the resin itself,
Preferred for achieving high flame retardancy. Further, an acid-modified polyolefin modified by reacting an unsaturated carboxylic acid such as maleic anhydride or acrylic acid or a derivative thereof during or after the polymerization of the above-mentioned polyolefin resin can also be used. These resins may be used alone or in a combination of two or more.

[0008] The metal hydrate used in the present invention decomposes into oxides and water vapor during combustion to exhibit flame retardancy.
Magnesium hydroxide is preferably used. When magnesium hydroxide (Mg (OH) ₂ ) is added to a polyolefin resin, magnesium hydroxide is decomposed into an oxide and water vapor during combustion, thereby lowering the temperature and generating oxygen by the generated steam. Control supply. Further, it is possible to prevent the flame from spreading to a new resin surface due to the attachment of the oxide to the burned portion. In the present invention, magnesium hydroxide surface-treated with a silane coupling agent or a higher fatty acid is preferably used from the viewpoints of preventing deterioration of mechanical properties of the resin composition, improving water resistance and acid resistance, and the like. In the present invention, the amount of magnesium hydroxide to be added is 10 parts by weight or more and 250 parts by weight or less, more preferably 40 parts by weight or more and 150 parts by weight or less based on 100 parts by weight of the polyolefin resin. If the added amount of magnesium hydroxide is too small, favorable flame retardancy cannot be obtained, and if it is too large, the resulting non-halogen flame-retardant resin composition will have significantly reduced mechanical properties and insulation resistance.

In the present invention, a heat-resistant anti-aging agent is added as an essential component in combination with magnesium hydroxide. The heat-resistant anti-aging agent in the present invention is, among anti-aging agents capable of preventing the oxidative deterioration of the flame-retardant resin composition of the present invention, particularly, the induction period θ at 200 ° C., which is around the temperature at which the resin burns, is log θ. > 0. Examples of such a heat resistant anti-aging agent include phenothiazine, Yoshinox 2246R, Yoshinox BHT, Nocrack 2
A phenolic antioxidant such as 00 can be used. In the present invention, the addition of the heat-resistant anti-aging agent can suppress the decomposition of the resin near the resin combustion temperature, thereby achieving a preferable flame retardancy. When the induction period θ at 200 ° C. of the heat-resistant anti-aging agent is log θ ≦ 0, the anti-aging agent is easily decomposed during combustion of the resin, so that good flame retardancy cannot be obtained. The effect in the vicinity is sufficiently obtained, and favorable flame retardancy is obtained. The amount of the heat resistant aging inhibitor to be added is 0.1 to 10 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the polyolefin resin.
5 parts by weight or more and 5 parts by weight or less. If the amount of the heat resistant aging inhibitor is less than 0.1 part by weight, the effect of addition is not obtained, and if it is more than 10 parts by weight, bleed out or blooming may occur on the surface of the resin layer, which is not preferable.

As described above, preferable high flame retardancy is achieved by adding magnesium hydroxide and the above-mentioned heat-resistant anti-aging agent to the above-mentioned polyolefin-based resin as essential components, and coating of electric wires, cables or similar products is achieved. When used as a material, the Electrical Appliance and Material Control Law, UL Standard, I
Non-halogen flame-retardant resin compositions that pass at least one of the combustion tests specified in EEE Standard 383 and IEC Standard 332-1 respectively, more preferably in accordance with the Electrical Appliance and Material Control Law and UL Standard A non-halogen flame-retardant resin composition that passes a certain combustion test.

In addition to the above compounding agents, ultraviolet absorbers, anti-aging agents, cross-linking agents, copper damage inhibitors, pigments, dyes and other coloring agents, small amounts of inorganic fine powder such as talc, etc. Any suitable additives can be blended, but those which do not contain halogen and especially lead (Pb) are selected. Further, it is preferable that harmful heavy metals such as cadmium (Cd) are not contained as much as possible, and it is preferable that the content of harmful heavy metals in the non-halogen flame-retardant resin composition of the present invention is suppressed to less than 0.1% by weight. Further, the non-halogen flame-retardant resin composition of the present invention may have a degree of foaming of less than 10%. Furthermore, when the non-halogen flame-retardant resin composition of the present invention is used as an insulating material, the volume resistivity is preferably set to 1 × 10 ¹³ (Ω · cm) or more. Also, when heat resistance is required,
Crosslinking may be performed if necessary.

Such a non-halogen flame-retardant resin composition has a self-extinguishing flame retardancy equivalent to that of PVC because its oxygen index (OI) is 24 or more, and is difficult to burn in a fire.
Low smoke emission. Further, since it does not contain halogen and does not generate toxic gases such as dioxin and halogen gas during combustion, it can be disposed of by incineration and does not generate toxic gas even in case of fire. Furthermore, there is no elution of lead, and landfill disposal is possible. Particularly, since the non-halogen flame-retardant resin composition of the present invention contains the above-mentioned heat-resistant antioxidant as an essential component, the resin in a high-temperature atmosphere is more heat-resistant than a resin to which an antioxidant having no heat resistance is added. Decomposition is suppressed, and longer use is possible.

The non-halogen flame-retardant resin composition of the present invention includes, for example, insulated wires, electronic device wiring wires, automobile wires, device wires, power cords, insulated wires for outdoor distribution, power cables, control cables, Insulation materials, sheath materials, tapes, and inclusions for various cables and cables such as communication cables, instrumentation cables, signal cables, transfer cables, and ship cables, as well as wires and cables for cases, plugs, and tapes. Cable accessories (specifically, shrink tubing, rubber stress relief cones, etc.), electrical materials such as conduits, wiring ducts, and bus ducts, as well as agricultural seats, water hoses, gas pipe coverings, and building interiors It is suitable for materials and floor materials. In particular, when the halogen-free flame-retardant resin composition of the present invention is used for electric wires and power cords, a product having excellent flexibility, good plug bending characteristics, and excellent plug portion tracking resistance can be obtained. .

[0014]

EXAMPLES Hereinafter, the effects of the present invention will be clarified by showing specific examples. As examples and comparative examples of the present invention,
Various components were blended in the blending ratios (unit: parts by weight) shown in Tables 1 and 2 below, and kneaded with a kneader to obtain a resin composition.
In order to conduct a combustion test, the kneaded resin composition was coated on a 2 mm ² conductor with a thickness of 0.8 mm using an extruder to produce an electric wire. The combustion test uses this electric wire to establish a 60 ° tilt combustion test specified in the Electricity Control Law combustion test, UL standard V
W-1 vertical combustion test, IEC standard 332-
1 and a vertical tray combustion test defined in IEEE Standard 383, respectively. The results are shown in the table.
The oxygen index (OI) according to the test method of JIS K7201, the tensile strength and the elongation according to the method described in JIS K6760 were measured, and the surface condition of the electric wire was observed. The results are shown in the table. A tensile strength of 1 kgf / mm ² or more and an elongation of 250% or more are considered good. In the comparative examples, all of the samples which failed the combustion test were not measured for tensile strength and elongation.

[0015]

[Table 1]

[0016]

[Table 2]

In the above Examples and Comparative Examples, the following resins and compounding agents were used, respectively. EVA: Melt flow rate (hereinafter referred to as MFR)
2.5, an ethylene-vinyl acetate copolymer having a vinyl acetate content of 19% EEA: MFR = 0.5, an ethyl acrylate content of 2
0% ethylene-ethyl acrylate copolymer EPR: Mooney viscosity ML1 + 4 (100 ° C) 40, ethylene content 70 mol%, propylene content 30 mol% ethylene propylene rubber PP: MFR = 4, density 0.91 g / cm ³ Polypropylene LLDPE: MFR = 0.7, density 0.92 g / cm ³
Linear low density polyethylene VLDPE: Ultra low density polyethylene with MFR = 4, density 0.91 g / cm ³ Magnesium hydroxide: Magnesium hydroxide with surface treatment of stearic acid Heat resistant anti-aging agent: Nocrack, manufactured by Ouchi Shinko Chemical Co., Ltd. 20
0 (chemical name: 2,6-Di-t-butyl-p-cresol) Antioxidant: Irganox1010 manufactured by Ciba-Geigy

[0018]

As described above, the non-halogen flame-retardant resin composition of the present invention has the same flame retardancy as PVC.
And because it does not contain halogen, it can be incinerated. Furthermore, according to the present invention, when used as a covering material for electric wires, cables or the like, the Electrical Appliance and Material Control Law, UL
Standards, IEEE Standard 383, and IEC Standard 332-
Thus, a non-halogen flame-retardant resin composition having high practicability can be passed, because it can pass one or more of the combustion tests respectively defined in No. 1.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 23/06 C08L 23/06 23/08 23/08 23/12 23/12 H01B 3/00 H01B 3 / 00 A (72) Inventor Hirotaka Sawada 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Corporation (72) Inventor Atsushi Suzuki 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Corporation (72 ) Inventor Hiroshi Matsui 1-5-1, Kiba, Koto-ku, Tokyo F-term in Fujikura Co., Ltd. (reference) 4J002 BB001 BB061 BB071 BB121 BB151 BF031 BG041 BG051 DE076 FD037 GQ01 5G303 AA06 AB20 BA12 CA01 CA09 ACB A5 AB ABA 5A BA15 BA22 BA24 BA26 CA01 CA04 CA07 CA51 CC03 CD09 CD13

Claims (3)

[Claims] 1. An induction period at 200 ° C. of logθ> 0 with respect to 100 parts by weight of a polyolefin resin, from 10 parts by weight to 250 parts by weight of magnesium hydroxide.
A non-halogen flame-retardant resin composition characterized by adding 0.1 to 10 parts by weight of a heat-resistant anti-aging agent as described above. 2. The polyolefin resin is an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-propylene rubber, a polypropylene, a linear low-density polyethylene, an ultra-low-density polyethylene, a medium-density polyethylene, 2. The non-halogen flame-retardant resin composition according to claim 1, comprising one or more members selected from the group consisting of polyethylene and high-density polyethylene. 3. When used as a covering material for electric wires, cables or the like, the electric appliance control law, UL standard,
The non-halogen flame-retardant resin composition according to any one of claims 1 and 2, wherein the composition passes at least one of the combustion tests specified in IEEE Standard 383 and IEC Standard 332-1. object.