JP2000191844A - Non-halogen flame retardant resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition exhibiting flame retardancy equal to that of a PVC resin and generating no toxic gas when subjected to incineration treatment by adding magnesium hydroxide, zinc borate and silicone powder to a polyolefinic resin. SOLUTION: To 100 pts.wt. of a polyolefinic resin are added 10-250 pts.wt. of magnesium hydroxide, 10-100 pts.wt. of zinc borate and 3-50 pts.wt. of silicone powder to give a non-halogen flame retardant resin composition. As the polyolefinic resin is preferable one comprising one or more than one selected among ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ethylene-propylene rubbers, polypropylenes and polyethylenes. This resin composition has an oxygen index of at least 24 and flame retardancy to pass at least one of burning tests each prescribed in the law regulating electric appliances, the UL standards, the IEEE standards 383 and the IEC standard 332-1.

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, a metal hydrate such as Mg (OH) ₂ is usually added to the resin composition. However, the desired high flame retardancy cannot be obtained with metal hydrate alone, or when a large amount of metal hydrate is added to obtain the desired high flame retardancy, properties such as mechanical properties are significantly deteriorated. is there.

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]

The above object can be attained by a non-halogen flame-retardant resin composition obtained by adding magnesium hydroxide, zinc borate, and silicone powder to a polyolefin resin. With respect to 100 parts by weight of the polyolefin resin, the addition amount of magnesium hydroxide is 10 parts by weight to 250 parts by weight, the addition amount of zinc borate is 10 parts by weight to 100 parts by weight, and the addition amount of silicone powder is 3 parts by weight. It is preferable that the amount is from 50 parts by weight to 50 parts by weight. It is preferable that the polyolefin-based resin is composed of one or more members selected from the group consisting of ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene rubber, polypropylene, and polyethylene. When the non-halogen flame-retardant resin composition of the present invention is used as a coating material for electric wires, cables, or the like, it can be used as an electric appliance control law, UL standard, IEEE standard 383, and IEC.
It can pass at least one of the combustion tests specified in the standard 332-1.

[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 using a flame retardant in combination, preferable high flame retardancy can be achieved.

The polyolefin resin used in the present invention includes ethylene-vinyl acetate copolymer (EVA),
Preferred are ethylene-ethyl acrylate copolymer (EEA), ethylene-propylene rubber (EPR), polypropylene (PP), polyethylene (PE) and the like. These resins may be used alone or in combination of two or more. It may be used by blending. The polyethylene preferably has a density of 0.88 to 0.96 g / cm ^3. For example, linear low density polyethylene (LLDPE) and very low density polyethylene (VLDPE) are suitably used. In particular, among the above resins, EVA and EEA are particularly high in flame retardancy of the resin itself. Therefore, it is preferable to use these alone or in a blend with another resin in view of improving the 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.

[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 stearic acid, an oxalate anion, a silane coupling agent or the like is preferably used for reasons such as improvement in affinity with a resin and improvement in thermal decomposition characteristics. 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. If the added amount is too large, the resulting non-halogen flame-retardant resin composition has significantly reduced mechanical properties and insulation resistance.

In the present invention, zinc borate and silicone powder are used as a flame retardant auxiliary in combination with magnesium hydroxide. If the amount of zinc borate is too small, the effect of addition to flame retardancy cannot be obtained, and if it is too large, the mechanical properties of the resin composition will be significantly impaired. More than 10
0 parts by weight or less, more preferably 10 parts by weight or more and 80 parts by weight or less. The addition amount of the silicone powder is 3 parts by weight or more and 50 parts by weight with respect to 100 parts by weight of the polyolefin resin.
It is at most 5 parts by weight, more preferably at least 5 parts by weight and at most 40 parts by weight. If the added amount of the silicone powder is less than 3 parts by weight, favorable flame retardancy cannot be obtained. If the added amount is more than 50 parts by weight, the cost of raw materials increases but the improvement in flame retardancy cannot be expected much.

As described above, preferable high flame retardancy is achieved by adding magnesium hydroxide, zinc borate, and silicone powder as essential components to the above-mentioned polyolefin resin, 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, IEEE standard 383, and IEC standard 33
It is possible to obtain a halogen-free flame-retardant resin composition that passes at least one of the combustion tests established in 2-1.

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. In this case, an appropriate additive can be added, but an additive that does not contain halogen or lead (Pb) is 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. Crosslinking may be performed as necessary, such as when heat resistance is required.

Such a non-halogen flame-retardant resin composition has an oxygen index (OI) of 24 or more, has a self-extinguishing flame retardancy equivalent to that of PVC, is difficult to burn in a fire, and has a small amount of smoke. . Also, because it does not contain halogen and does not generate toxic gases such as dioxin and halogen gas during combustion,
Can be incinerated and does not emit toxic gases in the event of fire. Environmentally friendly because it does not further contain phosphorus,
Also, since there is no elution of lead, landfill disposal is possible. The addition of silicone powder can improve the weather resistance of the resin. Conventionally, it is widely known to add carbon black to improve the weather resistance of a resin.However, when carbon black is added, the resin composition is colored black. Become. On the other hand, if silicone powder is added, weather resistance can be improved, and a resin composition having good coloring properties can be obtained because the resin does not become dark.

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.
Further, 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 K7127 were measured. The results are shown in the table. Tensile evaluation of strength 1 kgf / mm ² or more ○, × less than 1 kgf / mm ^2, evaluation of the elongation 250%
The above is shown as ○, 200% or more and less than 250% as Δ, and less than 200% as ×. In addition, the tensile strength and elongation were not measured for any of the four combustion tests that failed.

[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 1
4% ethylene-ethyl acrylate copolymer EPR: Mooney viscosity ML ^{1 + 4} (100 ° C.) 40, ethylene content 70 mol%, propylene content 30 mol% ethylene propylene rubber PP: MFR = 4, density 0.91 g / polypropylene cm ³ VLDPE: MFR = 4, ultra low density polyethylene LLDPE of density of ^{0.91g / cm 3: MFR = 0.7} , density of 0.92 g / cm ³
Linear Low Density Polyethylene Magnesium Hydroxide: Stearic Acid Surface Treated Magnesium Hydroxide Silicone Powder: Toray Dow Corning Silicone Co., Ltd., DC4-7081 Zinc Borate: Alkanex FRC-500, Mizusawa Chemical Industry Co., Ltd. Inhibitor (antiaging agent): Ciba-Geigy, Ir
ganox1010

[0018]

As described above, according to the present invention, P
A non-halogen flame-retardant resin composition having the same flame retardancy as VC and containing no halogen can be incinerated. Further, it is environmentally preferable because it does not contain a phosphorus compound. Further, the non-halogen flame-retardant resin composition of the present invention has excellent weather resistance and good coloring properties. Further, according to the present invention, when used as a covering material for electric wires, cables or the like, the Electric Appliance and Material Control Law, UL Standard, IEEE Standard 383, and IEC Standard 332-1.
Can pass at least one of the combustion tests established respectively, and thus a highly practical non-halogen flame-retardant resin composition can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // (C08L 23/02 83:04) (72) Inventor Takashi Edo 1-5 Kiba, Koto-ku, Tokyo No. 1 Inside Fujikura Co., Ltd. (72) Inventor Hirotaka Sawada 1-5-1, Kiba, Koto-ku, Tokyo Japan (72) Inventor Jun Suzuki 1-5-1, Kiba, Koto-ku, Tokyo Stock Company F-term in Fujikura (reference) 4J002 BB031 BB061 BB071 BB121 BB151 BB201 BB211 CP032 DE076 DK007 FB086 FB096 FD080 FD132 FD136 FD137 GA00 GL00 GN00 GQ00 GQ01 5G305 AA02 AA14 CA25 BA01 CA35 CA35

Claims (4)

[Claims] 1. A halogen-free flame-retardant resin composition characterized by adding magnesium hydroxide, zinc borate and silicone powder to a polyolefin resin. 2. The amount of magnesium hydroxide added is at least 10 parts by weight based on 100 parts by weight of the polyolefin resin.
2. The halogen-free composition according to claim 1, wherein the amount of zinc borate is 10 parts by weight or more and 100 parts by weight or less, and the amount of silicone powder is 3 parts by weight or more and 50 parts by weight or less. Flammable resin composition. 3. The polyolefin-based resin comprises one or more selected from the group consisting of ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-propylene rubber, polypropylene, and polyethylene. The non-halogen flame-retardant resin composition according to claim 1. 4. When used as a coating material for an electric wire, a cable or the like, the electric appliance control law, UL standard,
The non-halogen flame-retardant resin composition according to any one of claims 1 to 3, wherein the resin composition passes at least one of the combustion tests specified in IEEE Standard 383 and IEC Standard 332-1. object.