JPH0797490A - Flame-retardant resin composition and preparation thereof - Google Patents

Abstract

PURPOSE:To obtain a flame-retardant resin compsn. by blending a copolymer resin of ethylene with an alpha-olefin or the like, a phenolic novolak resin and an epoxy- modified polyolefin resin or a specific hydrogenated block copolymer with a hydrated metallic compd. CONSTITUTION:100 pts.wt. in total of (A) a copolymer resin of ethylene with an alpha- olefin, ethyl acrylate or methyl methacrylate, (B) a phenolic novolak resin, and (C) an epoxy-modified polyolefin resin or a resin prepd. by epoxy modification and hydrogenation of a block copolymer constituted of a polymer block(s) mainly comprising recurring units of an arom. vinyl compd. and a polymer block(s) mainly comprising recurring units of a conjugated diene compd. (provided that B:C=10:90 to 60:40, and A: B+C=80:20 to 40:60) are blended with 50-150 pts.wt. hydrated metallic compd. The components (B) and (C) are preliminarily melt-kneaded together, and then admixed with the components (A) and (D). The component (A) prevents downgrading of the properties of the resulting resin compsn. due to its being filled with a large amt. of the component (D). The component (B) imparts a flame retardancy to the compsn. The component (C) improves the cold resistance, etc., of the compsn. lowered by the component (B). This flame-retardant resin compsn. can be prevented from dripping and smoking when combusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended to be applied to coatings of electric wires and cables, hoses, sheets, injection products, etc., which do not generate harmful and corrosive halogen-based gas even when burned by a fire. And a flame-retardant resin composition.

[0002]

BACKGROUND OF THE INVENTION In order to impart flame retardancy to fin compositions, it has been achieved by adding a halogen compound and antimony trioxide to polyolefin. However, these compositions are halogen compositions, which are harmful to the human body because they generate a halogen-based gas during combustion, and are not preferable because they corrode metals. Also, the amount of smoke is large,
Due to poor visibility, evacuation and extinguishing activities of people during a fire were significantly limited. In particular, recently, from the viewpoint of safety, it has been strongly desired not to generate such a halogen-based gas. In view of such circumstances, attention has been paid to inorganic flame retardants that use a hydrated metal compound that emits very little smoke and is less harmful. In recent years, resin composites containing magnesium hydroxide, aluminum hydroxide and the like have been put to practical use in order to impart flame retardancy, but in these flame retardant resin compositions, the generation of halogen-based gas is prevented. However, there is a problem that a so-called drip phenomenon occurs in which the resin composition melts and drops at the time of combustion and fails a vertical combustion test, for example, a vertical combustion test (VW-1) of UL standard. Further, an improved flame retardant resin composition has been developed in which an ethylene acrylic acid elastomer is blended with an inorganic flame retardant such as aluminum hydroxide or magnesium hydroxide. However, this flame-retardant resin composition is excellent in drip property at the time of combustion and passes the JIS standard horizontal or 60 ° inclination combustion test, but it does not meet the UL standard. It did not pass the VW-1 test. If a large amount of the above inorganic flame retardant is added to improve the flame retardancy, the tensile strength,
There are drawbacks in that mechanical properties such as elongation are extremely lowered, and the viscosity of the resin composition becomes high, making extrusion molding difficult.

[0003]

DISCLOSURE OF THE INVENTION As a result of intensive studies in view of the present situation, the present invention has a flammability capable of preventing drip during combustion and passing the VW-1 test shown in UL standard. Moreover, the present invention provides a flame-retardant resin composition that produces little smoke during combustion.

[0004]

Means for Solving the Problems As a result of studying an ethylene copolymer and a phenol resin having good flame retardance, the present inventors have studied a method of simply blending an ethylene copolymer and a phenol novolac resin. Although the flame retardancy was improved by the method, it was found that there is a drawback that the characteristics such as cold resistance and heat resistance are deteriorated. Then, as a result of further study, an epoxy-modified polyolefin resin having an epoxy group which easily reacts with a phenolic resin, a polymer block containing at least one vinyl aromatic compound as a main component, and at least one conjugated diene compound as a main component. By blending one or more resins selected from the epoxy modified products of hydrogenated block copolymers obtained by hydrogenating a block copolymer composed of polymer blocks It has been found that the phenol novolac resin, which is brittle in terms of molecular weight, is covered, and that the conventional drawbacks such as cold resistance and mechanical properties are improved without impairing flame retardancy, thus completing the present invention. That is, the present invention is a composition comprising the following components (a) to (d), wherein 100 parts by weight of (a) + (b) + (c) [where (b):
(c) = 10: 90 to 60:40, (a): {(b) + (c)} = 80:20
To 40:60], the present invention relates to a flame-retardant resin composition containing 50 to 150 parts by weight of (d) and a method for producing the same. (a) one or more resins selected from a copolymer of ethylene and α-olefin, an ethylene-ethyl acrylate copolymer resin or an ethylene-methyl methacrylate copolymer resin, (b) a phenol novolac resin,
(c) Epoxy-modified polyolefin resin having an epoxy group in the molecule, a block composed of a polymer block mainly containing at least one vinyl aromatic compound and a polymer block mainly containing at least one conjugated diene compound One or more resins selected from epoxy modified products of hydrogenated block copolymers obtained by hydrogenating the copolymer, and (d) hydrated metal compound.

The component (a) of the present invention is added for the purpose of preventing the deterioration of the properties caused by filling a large amount of the hydrated metal compound. Examples of the α-olefin of the copolymer of ethylene and α-olefin used in the present invention include C _{3 to} C ₁₂ such as propylene, butene-1,
Pentene-1, hexene-1, heptene-1, octene-1, 4-methylpentene-1, 4-methylhexene-
Examples include 1,4,4-dimethylpentene-1, nonene-1, decene-1, undecene-1, and dodecene-1. The component (b) of the present invention is added for the purpose of suppressing smoke generation during combustion of the composition and imparting flame retardancy. The phenol novolac resin used in the present invention is not particularly limited and is commercially available. For example, phenols and formalin have a phenols / formaldehyde ratio of 0.5 to 1.0. The mixture is charged in a reaction vessel at various mixing ratios, and a catalyst such as oxalic acid, hydrochloric acid-sulfuric acid or toluenesulfonic acid is added, and the mixture is heated and refluxed for an appropriate period of time. It can be obtained by a method in which it is allowed to stand for dehydration and the remaining water and unreacted phenols are removed. The co-condensed phenol resin obtained by using these resins or a plurality of raw material components may be used alone or in combination of two or more kinds.

The component (c) of the present invention comprises an epoxy-modified polyolefin resin having an epoxy group in the molecule, at least one polymer block mainly containing a vinyl aromatic compound, and at least one conjugated diene compound. The one or more resins selected from the epoxy modified products of the hydrogenated block copolymer obtained by hydrogenating the block copolymer composed of the main polymer block have a relatively low molecular weight and are brittle. It is a very important component that has the function of improving the cold resistance and mechanical properties that decrease when a phenolic resin, which is a resin, is blended with an ethylene copolymer. Modified polyolefin containing an epoxy group in the molecule used in the present invention is not particularly limited and is commercially available, a copolymer of ethylene and glycidyl methacrylate or an ethylene-acrylic acid copolymer, Examples thereof include ethylene / methacrylic acid copolymers, ethylene / acrylate copolymers, terpolymers of ethylene / methacrylate copolymers and glycidyl methacrylate, polypropylene (PP) grafted with glycidyl methacrylate, and the like. The hydrogenated block copolymer containing an epoxy group used in the present invention is not particularly limited and is commercially available. Epoxidized styrene-ethylene / butylene-styrene block copolymer, epoxidized styrene-ethylene. -A propylene-styrene block copolymer etc. are mentioned. The epoxy-modified block copolymer used in the present invention is a block copolymer before hydrogenation,
It can be obtained by addition reaction of an epoxy compound having an unsaturated double bond.

The flame-retardant resin composition of the present invention is selected from the copolymer of ethylene and α-olefin as the component (a), ethylene-ethyl acrylate copolymer resin or ethylene-methyl methacrylate copolymer resin. 1 or 2
At least one resin, (b) a phenol novolac resin, (c) an epoxy-modified polyolefin resin having an epoxy group in the molecule of the component, at least one polymer block mainly containing a vinyl aromatic compound, and at least one One or more resins selected from the epoxy modified products of hydrogenated block copolymers obtained by hydrogenating a block copolymer consisting of a polymer block mainly composed of the conjugated diene compound of ) A hydrated metal compound is added all at once, and the pressure kneader or Banbury mixer is used at 150 to 200 ° C. for 10 minutes.
Melt kneading for 30 minutes, or a phenol novolac resin of component (b) and an epoxy-modified polyolefin resin having an epoxy group in the molecule of component (c), at least 1
Epoxy of hydrogenated block copolymer obtained by hydrogenating a block copolymer composed of a polymer block mainly containing vinyl aromatic compounds and at least one polymer block mainly containing conjugated diene compounds One or two or more kinds of resins selected from the modified products are preliminarily set at 160 ° C.
After melt-kneading at 200 ° C. for 10 to 30 minutes, the components (a) and
It can be obtained by a method of adding the component (d) and further melt-kneading. The latter is the same as the phenol novolac resin of the component (b).
Component (c) comprises an epoxy-modified polyolefin resin having an epoxy group in the molecule, a polymer block mainly containing at least one vinyl aromatic compound, and a polymer block mainly containing at least one conjugated diene compound. It is more preferable that one or two or more resins selected from the epoxy modified products of the hydrogenated block copolymer obtained by hydrogenating the block copolymer are selectively mixed.

In the flame-retardant resin composition of the present invention, (b)
Component phenol novolac resin and component (c) epoxy-modified polyolefin resin, consisting of at least one vinyl aromatic compound-based polymer block and at least one conjugated diene compound-based polymer block One or two or more resins selected from the epoxy modified products of the hydrogenated block copolymer obtained by hydrogenating the block copolymer at a ratio of 10:90 to 60:40, (a)
(B) + (c) for one or more resins selected from the copolymer of ethylene and α-olefin as a component, ethylene-ethyl acrylate copolymer resin or ethylene-methyl methacrylate copolymer resin 80: 20-40: 60
Must be blended in the ratio. (b) Component phenol novolac resin, (c) component epoxy-modified polyolefin resin, at least one vinyl aromatic compound-based polymer block, and at least one conjugated diene compound-based polymer Epoxy-modified polyolefin resin of component (c) in one or a mixture of two or more resins selected from epoxy-modified products of hydrogenated block copolymers obtained by hydrogenating a block copolymer composed of blocks A hydrogenated block copolymer obtained by hydrogenating a block copolymer composed of at least one vinyl aromatic compound-based polymer block and at least one conjugated diene compound-based polymer block If the proportion of one or more resins selected from the combined epoxy-modified products is less than 40 wt%, the phenol resin (a)
Cold resistance that decreases when compounded with one or more resins selected from the copolymer of ethylene and α-olefin as a component, ethylene-ethyl acrylate copolymer resin, or ethylene-methyl methacrylate copolymer resin However, the improvement of mechanical properties becomes insufficient, and when it exceeds 90 wt%, the phenol novolac resin becomes less than 10 wt%, and the effect of improving flame retardancy becomes insufficient. Also, for component (a)
If the amount of the components (b) + (c) is less than 20 wt%, the flame retardancy-improving effect becomes insufficient, and if it exceeds 60 wt%, various advantages of the component (a) are reduced.

Thus, the flame-retardant resin composition of the present invention is
Component (a) selected from ethylene-α-olefin copolymer, ethylene-ethyl acrylate copolymer resin or ethylene-methyl methacrylate copolymer resin 1
It has the effect of improving the flame retardancy without substantially deteriorating the characteristics of one or two or more resins. The reason is that the (b) component phenol novolac resin and the (c) component epoxy are used. Hydrogenation obtained by hydrogenating a modified polyolefin resin, a block copolymer composed of at least one vinyl aromatic compound-based polymer block and at least one conjugated diene compound-based polymer block By reacting the epoxy groups of one or more resins selected from the epoxy modified products of the block copolymer, the phenol novolac resin of component (b) and the epoxy modified polyolefin resin of component (c), at least A polymer block mainly composed of one vinyl aromatic compound,
One or more resins selected from the epoxy-modified products of hydrogenated block copolymers obtained by hydrogenating a block copolymer composed of a polymer block containing at least one conjugated diene compound as a main component. Has a sea-island structure and covers the brittleness of the phenolic resin, and is selected from a copolymer of ethylene and α-olefin of component (a), an ethylene-ethyl acrylate copolymer resin or an ethylene-methyl methacrylate copolymer resin. (B) a phenol novolac resin as a component, and (c)
Component epoxy modified polyolefin resin, at least 1
Epoxy of hydrogenated block copolymer obtained by hydrogenating a block copolymer composed of a polymer block mainly containing vinyl aromatic compounds and at least one polymer block mainly containing conjugated diene compounds It is considered that the mixture with one or two or more kinds of resins selected from the modified products can have a microphase-separated structure.

The hydrated metal compound used in the present invention has a decomposition initiation temperature in the range of 150 to 450 ° C.,
A compound represented by the general formula MmOn.XH ₂ O (where M is a metal, m and n are integers of 1 or more determined by the valence of the metal, and X is a number of contained waters of crystallization), or a double salt containing the compound. Specifically, aluminum hydroxide [Al ₂ O ₃ .3H ₂ O;
Or Al (OH) ₃ ], magnesium hydroxide [MgO · H ₂ O; or Mg (OH) ₂ ], calcium hydroxide [CaO · H ₂ O; or
Ca (OH) ₂ ], barium hydroxide [BaO ・ H ₂ O; or BaO ・ 9
H ₂ O], zirconium oxide hydrate (ZrO · nH ₂ 0), tin oxide hydrate [SnO · H ₂ 0], basic magnesium carbonate [3MgC
O ₃ · Mg (OH) ₂ · 3H ₂ O], hydrotalcite [6MgO · Al ₂
O ₃ · H ₂ O], dawsonite [Na ₂ CO ₃ · Al ₂ O ₃ · nH ₂ O], borax [Na ₂ O · B ₂ O ₅ / 5H ₂ O], zinc borate [nB ₄ O ₇ · 2ZnO]
Etc. If the addition amount of these is 50 parts by weight or less, the desired flame retardant effect is difficult to obtain, and if it is 150 parts by weight or more, mechanical properties such as tensile strength are deteriorated and extrusion processability is deteriorated. As the other additive, the flame-retardant composition of the present invention optionally contains an additive commonly used, for example, an antioxidant,
Neutralizers, UV absorbers, antistatic agents, pigments, dispersants, lubricants, thickeners, foaming agents, metal deterioration inhibitors, fungicides, flow regulators, etc., and flame retardants of phosphorus and phosphine derivatives,
Other inorganic fillers, cross-linking agents, cross-linking aids, etc., or other synthetic resins may also be included. It is also possible to crosslink by electron beam irradiation.

[0011]

EXAMPLES Examples will be described below. Among the compounding agents shown in Tables 1, 2 and 3, the components (b) (3 to 6) and the components (c) (7 to 8) are kneaded at a temperature of 140 to 150 ° C. using a pressure kneader to prepare a mixture. Grained. The crude product obtained in this way
(a) Component (1-2), hydrated metal compound, and lubricant, stabilizer are added, and the extrusion temperature is 190-2 by using a bi-directional extruder.
The mixture was kneaded at 10 ° C and granulated. The obtained composition was roll-pressed to prepare a test piece for measurement, and the oxygen index and cold resistance were evaluated. Also, using a 50 mmφ extruder (L / D = 22),
The 0.85 mm outer circumference of the conductor was extrusion-coated to a thickness of 1.05 mm with the flame-retardant resin composition to prepare an insulated wire. The insulated wire was evaluated for flame retardancy (UL standard vertical combustion test: VW-1), presence or absence of drip during combustion, tensile properties, and the like. The evaluation results are shown in Tables 1, 2 and 3.

[0012]

[0013]

[0014]

Note: The compounding agents used and the evaluation method are as follows. (1) Nippon Petrochemical Softlex (Ethylene-α
-Olefin Copolymer) (2) Nippon Petrochemical Rexlon (Ethylene-Ethyl Acrylate Copolymer) (3) Sumitomo Dures Sumirite Resin R (Straight Phenol Novolac Resin) (4) Sumitomo Dures Sumirite Resin R ( Paraoctylphenol novolac resin) (5) Sumitomo Durez Sumilite Resin R (aromatic hydrocarbon resin modified phenol novolac resin / modification rate: 4)
0%) (6) Sumitomo Durez made Sumilite resin R (oil modified phenol novolac resin) (7) Sumitomo Chemical Co., Ltd. Bondfast R (epoxy modified polyolefin resin / epoxy equivalent: about 0.42mol
/ G) (8) Tuftec R (epoxy-modified styrene-made by Asahi Kasei)
Ethylene / butylene-styrene block copolymer / epoxy equivalent: about 0.1 mmol / g) (9) Showa Denko's Heidilite H42M (10) Kyowa Chemical's Kisuma 5B (11) Sanyo Kasei Kogyo Sunwax 171P 1.0 Parts by weight Ciba Geigy Irganox 1076 0.3 parts by weight Sumitomo Chemical Co., Ltd. Sumizer WXR 0.3 parts by weight mixture (12) 50 mmφ single screw extruder (L / D = 24): Compression ratio: 3.5 Extrusion temperature: 120-150-160- 170-170 (℃) Conductor diameter: 0.85mm Coating thickness: 1.05mm ○: Good extrudability ×: Not extrudable (13) Vertical combustion test of UL standard (VW-1) (14) Conforms to JIS K 7201 (15) Conforms to JIS K 6723 (16) Conforms to JIS K 6760

[0016]

As is clear from the table, according to the flame-retardant resin composition of the present invention, the drip property at the time of combustion can be prevented, and the high flame-retardant property of passing VW-1 shown in UL standard. In addition, it is industrially useful because it has excellent mechanical properties without generating harmful gas during combustion.

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[Procedure amendment]

[Submission date] November 5, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

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[Correction method] Change

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[0011]

EXAMPLES Examples will be described below. Among the compounding agents shown in Tables 1 and 2, (b) component (3 to 6) and (c) component (7
~ 8) were kneaded using a pressure kneader at a temperature of 140 to 150 ° C and granulated. Component (a) (1 to 2), a hydrated metal compound, a lubricant and a stabilizer are added to the crude product thus obtained, and the extrusion temperature is 190 to 210 ° C. using a bidirectional extruder with different directions. It was kneaded and granulated. The obtained composition was roll-pressed to prepare a test piece for measurement, and the oxygen index and cold resistance were evaluated. Also, using a 50mmφ extruder (L / D = 24), the outer diameter is 0.85mm
The above flame-retardant resin composition was extrusion-coated to a thickness of 1.05 mm on the outer circumference of the conductor to prepare an insulated electric wire. The insulated wire was evaluated for flame retardancy (UL standard vertical combustion test: VW-1), presence or absence of drip during combustion, tensile properties, and the like. The evaluation results are shown in Tables 1 and 2.

[Procedure Amendment 2]

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[Correction method] Change

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[0012]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0013

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[0013]

Claims (2)

[Claims] 1. A composition comprising the following components (a) to (d): 100 parts by weight of (a) + (b) + (c) [however,
(b) :( c) = 10: 90 to 60:40, (a): {(b) + (c)} =
80:20 to 40:60], and 50 to 150 parts by weight of (d) are contained in the flame-retardant resin composition. (a) one or more resins selected from a copolymer of ethylene and α-olefin, an ethylene-ethyl acrylate copolymer resin or an ethylene-methyl methacrylate copolymer resin, (b) a phenol novolac resin,
(c) Epoxy-modified polyolefin resin having an epoxy group in the molecule, a block composed of a polymer block mainly containing at least one vinyl aromatic compound and a polymer block mainly containing at least one conjugated diene compound One or more resins selected from epoxy modified products of hydrogenated block copolymers obtained by hydrogenating the copolymer, and (d) hydrated metal compound. 2. (b) Phenol novolac resin and (c)
Epoxy-modified polyolefin resin having an epoxy group in the molecule, block copolymer composed of a polymer block mainly containing at least one vinyl aromatic compound and a polymer block mainly containing at least one conjugated diene compound 1 or 2 or more resins selected from the epoxy modified products of the hydrogenated block copolymer obtained by hydrogenating the above are blended in a ratio of 10:90 to 60:40, melt-kneaded in advance, and then (a) one or more resins selected from a copolymer of ethylene and α-olefin, an ethylene-ethyl acrylate copolymer resin or an ethylene-methyl methacrylate copolymer resin, and (d) a hydrated metal compound A method for producing a flame-retardant resin composition, which comprises adding