JP2003073512A - Flame-retardant extrusion rubber composition and sealing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant extrusion rubber composition having an excellent cost-performance ratio and having excellent flame retardancy and processability, and to provide a sealing material. SOLUTION: This flame-retardant extrusion rubber composition contains an ethylene-α-olefin-nonconjugate polyene copolymer and a non-halogen-based flame retardant. The copolymer, for example, has an ethylene/α-olefin ratio (in mol) of 40/60 to 95/5 and contains 0-25 wt.% of the nonconjugate polyene which has an intrinsic viscosity of 0.8-5.0 dl/g measured in xylene at 70 deg.C, a Q-value (a ratio of a weight- average molecular weight to a number-average molecular weight) of 4-20 measured by gel permeation chromatography (GPC), and characteristic numbers of I and A (1) obtained from a molecular-weight distribution curve and satisfying: I>=2; and 1.5<=A (1)<=3.0 [I and A (1) are each defined in the specification]. A phosphorus-based flame retardant, a metal oxide or a hydrated metal oxide is preferably used as the non- halogen-based flame retardant. Triphenyl phosphate and tricresyl phosphate are exemplified as the phosphorus-based flame retardant. Antimony trioxide is exemplified as the metal oxide. Aluminum hydroxide and magnesium hydroxide are exemplified as the hydrated metal oxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition used as a sealing material and the like, and more particularly to a rubber composition for extrusion which has flame retardancy and is used as a sealing material for building materials, railway vehicles and automobiles. Is related to.

[0002]

BACKGROUND ART So-called self-extinguishing polymers include polyvinyl chloride (PVC), chloroprene (CR) and silicone (Q) compositions. These are materials for automobiles and materials for railway vehicles. It is used for building materials, industrial parts materials, etc. The general characteristics of the composition are briefly summarized in Table 1. In the symbols in the table, ⊚ means particularly excellent, ○ means excellent, Δ means slightly inferior, and × means inferior.

[0003]

[Table 1]

Polyvinyl chloride (PVC) based compositions are
In addition to self-extinguishing property, it is also excellent in weather resistance and adhesiveness, and particularly excellent in cost performance, but is inferior in heat resistance and cold resistance.

Chloroprene-based (CR) -based compositions are superior in self-extinguishing property and adhesiveness, but are considered to be slightly inferior in heat resistance, cold resistance, weather resistance, electrical insulation, panel contamination, and cost performance. ing.

The silicone (Q) composition has, in addition to self-extinguishing property, particularly heat resistance, cold resistance, weather resistance, electrical insulation,
It is said to have excellent panel stain resistance, but poor adhesiveness and cost performance.

The characteristics of the ethylene-propylene-diene (EPDM) composition are also shown in the table. Although the composition is inferior in self-extinguishing property, it is said to be excellent in heat resistance, cold resistance, panel stain resistance, adhesiveness, cost performance, and particularly excellent in weather resistance and electric insulation. The adhesion is said to be further improved by using a primer.

Although there is no self-extinguishing property,
Ethylene-propylene-with excellent cost performance and excellent performance balance as an elastomer for sealing
If flame retardancy can be added to the diene (EPDM) composition (Table 1), it is expected that it can be used as a very useful flame retardant sealant.

However, when obtaining a flame-retardant rubber composition based on EPDM, it is necessary to compound a large amount of flame-retardant compounding materials. In addition, the physical properties, particularly the extrusion processability, are remarkably deteriorated by this, and it cannot be used as a material for the above-mentioned construction and vehicles under the present circumstances.

The present invention has been made in view of the above circumstances, and its object is to provide a flame-retardant rubber composition for extrusion and a sealing material which are excellent in cost performance, flame retardancy and processability. ,It is in.

[0010]

Therefore, the present invention for solving the above-mentioned problems is characterized as follows.

The invention according to claim 1 contains the following ethylene-α-olefin-non-conjugated polyene copolymer (a) or (b) and a halogen-free flame retardant, and is extrudable. (ASTM-D-2230-90, scoring criteria B) is 6A to 10A, which is a flame-retardant rubber composition for extrusion. (A) The ethylene / α-olefin ratio (molar ratio) is 4
0/60 to 95/5, 0 to 25% by weight of non-conjugated polyene, and an intrinsic viscosity of 0.
The Q value (weight average molecular weight / number average molecular weight) measured by GPC is 4 to 20 at 8 to 5.0 dl / g, and the peak characteristic numbers I and A (1) obtained from the molecular weight distribution curve are I ≧
2 and ethylene-α- with 1.5 ≦ A (1) ≦ 3.0
Olefin-non-conjugated polyene copolymer. (B) The ethylene / α-olefin ratio (molar ratio) is 8
In 3/17 to 97/3, the sum of α-olefin and non-conjugated polyene is 6 to 19 mol%, A obtained from the following formula is A ≧ 0.1, A = (42P + 120D) / (42P + 120D + 28
E) P: content of α-olefin in copolymer rubber (mol%) D: content of non-conjugated polyene (mol%) E: content of ethylene (mol%) Intrinsic viscosity measured in 70 ° C. xylene , 0.8-4.
At 0 dl / g, melting peak temperature by DSC measurement is 70
An ethylene-α-olefin-non-conjugated polyene copolymer having a heat of fusion of 10 cal / g or less at a temperature of ℃ or less.

The invention of claim 2 provides the flame-retardant rubber composition for extrusion according to claim 1, wherein the ethylene-α-olefin-non-conjugated polyene copolymer (a) and ethylene-α-
And an olefin-non-conjugated polyene copolymer (II).

According to a third aspect of the present invention, in the flame-retardant rubber composition for extrusion according to the second aspect, an ethylene-α-olefin-non-conjugated polyene copolymer (a) / ethylene-α- is used.
The olefin-non-conjugated polyene copolymer (b) ratio (weight ratio) is 5/95 to 95/5.

According to a fourth aspect of the present invention, in the flame-retardant extrusion rubber composition according to the first to third aspects, the non-halogen flame retardant is a phosphorus flame retardant, a metal oxide or a hydrated metal oxide. A flame-retardant rubber composition for extrusion.

The invention according to claim 5 is a sealing material comprising a flame-retardant extrusion rubber composition, wherein the flame-retardant extrusion rubber composition is the rubber composition according to any one of claims 1 to 4. It is characterized by

In the above invention, examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. Of these, propylene and 1-butene are preferred.

Non-conjugated polyenes include 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-
Hexadiene, 6-methyl-1,5-heptadiene, 7
Chain non-conjugated dienes such as -methyl-1,6-octadiene, cyclohexadiene, dicyclopentadiene,
Methyl tetraindene, 5-vinyl norbornene, 5-
Ethylidene-2-norbornene, 6-chloromethyl-5
A cyclic conjugated diene such as -isopropenyl-2-norbornene, 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, Trienes such as 1,3,7-octatriene and 1,4,9-decatriene are exemplified, and one of them may be used alone, or two or more thereof may be used in combination. 5-Ethylidene-2-norbornene and / or dicyclopentadiene are preferred.

Further, 5-vinyl-2-norbornene,
5- (2-propenyl) -2-norbornene, 5- (3
-Butenyl) -2-nobornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2
-Norbornene, 5- (5-heptenyl) -2-norbornene, 5- (7-octenyl) -2-norbornene,
5-methylene-2-norbornene, 6,10-dimethyl-1,5,9-undecatriene, 5,9-dimethyl-
1,4,8-decatriene, 4-ethylidene-8-methyl-1,7-nonadiene, 13-ethyl-9-methyl-
1,9,12-pentadecatriene, 5,9,13-trimethyl-1,4,8,12-tetradecadiene, 8,
Examples include 14,16-trimethyl-1,7,14-hexadecatriene, 4-ethylidene-12-methyl-1,11-pentadecadiene and the like.

In the copolymers (a) and (b), the ethylene-α-olefin-non-conjugated polyene copolymer is disclosed in a known production method, for example, JP-A-62-138509 and JP-B-7-14982. It is obtained by a method similar to the production method.

That is, a trivalent to pentavalent vanadium catalyst, a general formula, RmAlX3-3 (0 <m ≦ 3, R is C1 to C1)
By using a catalyst consisting of an organoaluminum compound represented by an alkyl group of 0, X is a halogen) and an ester of a halogenated organic acid in a specific ratio.
A propylene / non-conjugated polyene copolymer can be obtained. The copolymerization to obtain the copolymer is carried out by using a hydrocarbon solvent such as pentane, hexane, heptane, an aliphatic hydrocarbon such as octane or kerosene, an alicyclic hydrocarbon such as cyclohexane, benzene, toluene or xylene. The aromatic hydrocarbon is used alone or in a mixed solvent. The polymerization temperature at this time can be set within a wide range, but is usually -50 to 100 ° C. Polymerization is performed under atmospheric pressure or under pressure, for example, 0.1 to 5 MPa.
It is carried out under pressure. Further, a molecular weight modifier is used in order to arbitrarily control the molecular weight of the produced copolymer. Examples of the molecular weight modifier include diethylaene, acrylic chloride, pyrimidine-N-oxide, hydrogen and the like.

In the copolymer (a), GPC means gel permeation chromatography (Gel Pearmeation Chromatogr).
a value), and the Q value is the ratio of the weight average molecular weight (MW) to the average molecular weight (MN), and is represented by Q = MW / MN. The magnitude of the Q value indicates that the molecular weight distribution is wide and narrow.

The Q value measured by GPC is more preferably 4 to 20. Furthermore, the peak characteristic numbers I, A (i) and A (M) obtained from the molecular weight distribution curve are A (i) <
Within the range of A (M), I ≧ 2, 1.5 ≦ A (1) ≦ 3.0
Is more preferable.

Here, the peak characteristic numbers A (M), I, A
(I) is obtained from the average distribution curve and is defined as follows (JP-A-62-138509). Let A (M) be the logarithm of the chain length showing the main peak of the distribution constant curve of the molecular weight. Further, in the molecular weight distribution curve, if the horizontal axis is the logarithm of the chain length in polystyrene equivalent (log (chain length)) and the vertical axis is the relative concentration (H) of the copolymer having each molecular chain length, this derivative Is defined by dH / d (log (chain length)). When the differential value thus obtained is plotted on the vertical axis and the logarithm of the chain length is plotted on the horizontal axis, the differential curve of the molecular weight distribution curve is obtained. dH / d (log (chain length)) is represented by DH, and the logarithm of the chain length showing a peak where DH> 0 is A
(I). That is, the logarithms of the chain lengths for the peaks P1, P2, ..., Pi are A (1), A (2) ,.
(I). However, Pi is assumed to be in the range of A (i) <A (M). The maximum value of i thus obtained is I.

On the other hand, in the copolymer (II), the DSC measurement value is an index showing the presence of fine crystals in the polymer (Japanese Patent Publication No. 7-14982). The melting peak temperature and the heat of fusion are obtained from the endothermic peak of the DSC melting curve (the same publication).

The copolymers (a) and (b) can be vulcanized. Examples of the vulcanizing agent include sulfur and peroxide. In the case of sulfur vulcanization, sulfur is, for example, 0.1 to 10 and preferably 0.5 to 100 parts by weight of the copolymer.
It is used in a ratio of 5.0 parts by weight. Moreover, a vulcanization accelerator and a vulcanization acceleration aid are added as needed. As the vulcanization accelerator, a sulfenamide type, a thyrium type, a dithiocarbamate type, a xanthate type, or the like is appropriately combined and used. As the vulcanization acceleration aid, zinc oxide (zinc white) and stearic acid are used in combination. On the other hand, in the case of peroxide vulcanization, examples of the peroxide include benzoyl peroxide, dicumenyl peroxide, tert-butyl perbenzoate, 2,2-di (tert-butylperoxy) butane, and 2,2′-azo. Bisisobutyronitrile or the like is used. In this case, as a vulcanization aid,
Polyfunctional monomers such as sulfur or metaphenylene bismaleide, and oxime compounds such as p-quinonedioxime are used.

The copolymers (a) and (b) may be used alone or in other rubber materials such as natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SB).
R), acrylonitrile-butadiene rubber (NBR), etc. can be blended and used.

Of the non-halogen flame retardants, first, phosphoric acid ester flame retardants are effective as phosphorus flame retardants, and examples thereof include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, and triethyl. Phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, cresyl bis (di2,6-xylenyl) phosphate, 2-
Examples thereof include ethylhexyl diphenyl phosphate and dimethyl methyl phosphate. The blending amount of the non-halogen flame retardant is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the copolymer in consideration of its flame retardant effect and adverse effect on processability.

Examples of the metal oxide include antimony trioxide and the like, and examples of the hydrated metal oxide include aluminum hydroxide, magnesium hydroxide, hydrotalcite, calcium hydroxide, barium hydroxide and the like. Is mentioned. The amount of the metal oxide or hydrated metal oxide blended is preferably 5 to 200 parts by weight with respect to 100 parts by weight of the copolymer.

In the rubber composition according to the present invention, carbon black, in the range that does not impair the effects of the present invention,
A reinforcing agent such as silica, an inorganic filler such as talc (magnesium silicate) and clay (aluminum silicate), a petroleum oil such as paraffin oil, a lubricant, and an antiaging agent are appropriately mixed.

A silane coupling agent may be added to the composition for the purpose of further reinforcing the composition. As the silane coupling agent, for example, a mercaptosilane-based agent such as 3-mercaptopropyltrimethoxysilane or a tetrasulfide-based agent such as bis- (3-triethoxysilylpropyl) tetrasulfide is appropriately used.

The rubber composition according to the present invention described above is AST
The scoring standard B of MD-2230-90 is 6A to 10A, and the flame retardancy index UL-94V after vulcanization is 94V-.
A flame retardancy level of 2 or more can be expressed.

Therefore, according to the rubber composition of the present invention, it is possible to provide a flame-retardant rubber composition for extrusion and a sealing material which are excellent in cost performance, flame retardancy and processability. . Further, since the present invention uses the halogen-free flame retardant, there is no concern that the environment will be polluted.

Further, by blending the copolymer (a), in addition to high flame retardancy, it exhibits extremely good processability (roll processability, extrusion processability) and further has excellent tensile strength physical properties. It is possible to provide a flame-retardant rubber composition for extrusion and a sealing material. Furthermore, by blending the copolymer (b), in addition to high flame retardancy, blending a flame-retardant material makes it possible to reduce the physical properties that are likely to occur, and it is rich in elastic properties and vulcanized. It is possible to provide a flame-retardant rubber composition for extrusion and a sealing material which have sufficiently high rubber strength and meet high performance requirements. The rubber composition according to the present invention is a sealing material,
In particular, it can be used as a sealing material for building materials, railway vehicles, and automobiles.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

The rubber composition according to the present invention comprises ethylene-α
-Contains an olefin-non-conjugated polyene copolymer and a non-halogen flame retardant.

The above copolymers have an ethylene / α-olefin ratio (molar ratio) of 40/60 to 95/5 and a non-conjugated polyene of 0 to 25% by weight, and the ultimate limit measured in xylene at 70 ° C. Viscosity of 0.8-5.0 dl / g, GP
Q value by C measurement (weight average molecular weight / number average molecular weight)
Is 4 to 20, and the peak characteristic numbers I and A (1) obtained from the molecular weight distribution curve are I ≧ 2 and 1.5 ≦ A (1) ≦
An ethylene-α-olefin-non-conjugated polyene copolymer (a) of 3.0 and an ethylene / α-olefin ratio (molar ratio) of 83/17 to 97/3, an α-olefin and a non-conjugated polyene. Is 6 to 19 mol%, A obtained from the following formula is A ≧ 0.1, and the intrinsic viscosity measured in 70 ° C. xylene is 0.8 to 4.0 dl / g, and DS
Ethylene-α-olefin-having a melting peak temperature of 70 ° C. or less and a heat of fusion of 10 cal / g or less by C measurement
There is a non-conjugated polyene copolymer (b).

A = (42P + 120D) / (42P + 1
20D + 28E) P: Content of α-olefin in copolymer rubber (mol%) D: Content of non-conjugated polyene (mol%) E: Content of ethylene (mol%) In copolymer (a) (b) As the α-olefin, for example, propylene, 1-butene, 1-pentene,
1-Hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like are used. Examples of the non-conjugated polyene include chain non-conjugated dienes such as 1,4-hexadiene, cyclic non-conjugated dienes such as dicyclopentadiene and 5-ethylidene-2-norbornene, 2,3-diisopropylidene-
Examples thereof include trienes such as 5-norbornene, and one type thereof may be used alone, or two or more types may be used in combination.

Non-halogen flame retardants include phosphorus flame retardants,
There are metal oxides and hydrated metal oxides. As the phosphorus-based flame retardant, triphenyl phosphate, tricresyl phosphate and the like are used. As the metal oxide, antimony trioxide or the like is used. As the hydrated metal oxide, aluminum hydroxide, magnesium hydroxide, hydrotalcite, calcium hydroxide, barium hydroxide or the like is used.

In the rubber composition according to the present invention, the blending ratio of the copolymer and the flame retardant is, for example, the copolymer 1
The flame retardant is 5 to 200 parts by weight with respect to 00 parts by weight.

The copolymers (a) and (b) can be blended alone or in combination with a non-halogen flame retardant. When the copolymers (a) and (b) are used in combination, for example, the copolymer (a) / copolymer (b) ratio (weight ratio) is 5
It is blended so as to be / 95 to 95/5.

The copolymers (a) and (b) are obtained by reacting a catalyst with ethylene, an α-olefin and a non-conjugated polyene under an organic solvent at a constant temperature under atmospheric pressure or under pressure. To be For example, under a polymerization temperature of 50 to 55 ° C., an hexane solvent, a catalyst, ethylene, an α-olefin, and a non-conjugated polyene are placed in an autoclave equipped with a stirrer, and the ethylene content in the obtained copolymer is increased. And quantitatively supplying the non-conjugated polyene content to a predetermined amount. At this time, hydrogen as a molecular weight regulator may be supplied. The reaction solution is continuously extracted, a polymerization terminator is added, and then a copolymer is deposited by steam stripping and dried. As the catalyst, a trivalent to pentavalent vanadium catalyst, a general formula, R _m AlX _3-m (0 <m ≦
3, R is an alkyl group of C1 to C10, X is an organoaluminum compound represented by halogen), and an ester of a halogenated organic acid is used. The ethylene content and the non-conjugated polyene content are confirmed by infrared absorption spectrum analysis or the like.

The rubber composition according to the present invention contains sulfur, a vulcanizing agent, and a vulcanization accelerator, if necessary, in addition to the above-mentioned copolymer and the above flame retardant, and is further reinforced with carbon black or the like. Agent, talc, inorganic filler such as clay, other flame retardant, lubricant, anti-aging agent, etc. are added, open roll,
It is recommended to knead with a Banbury mixer or the like. The rubber composition thus obtained is used, for example, as a sealing material, particularly as a sealing material for building materials, railway vehicles, and automobiles.

Examples and comparative examples of the present invention will be described. (Example 1) As shown in Table 2, tricresyl phosphate was added to 100 parts by weight of a copolymer having 70 parts by weight of the polymer (a) component and 30 parts by weight of the polymer (b) component. 5 parts by weight, 150 parts by weight of aluminum hydroxide, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 2 parts by weight of silane coupling agent, carbon black (M
AF grade) 5 parts by weight, paraffin oil 10 parts by weight,
1.5 parts by weight of sulfur was added, and as a vulcanization accelerator,
1.5 parts by weight of BZ (zinc dibutyldithiocarbamate), 1 part by weight of CZ (N-cyclohexylbenzothiazolylsulfenamide) and 1 part of TRA (dipentamethylenethylium hexasulfide), TT (tetramethylthylium disulfide) ) Was added and kneaded, and then molded to obtain a rubber composition according to the present example.

Here, the polymer (a) is ethylene-α.
-Olefin-non-conjugated polyene copolymer, ethylene /
α-olefin ratio (molar ratio) is 78/22, non-conjugated polyene weight% is 7.0, intrinsic viscosity is 1.28 dl / g, G
The PC Q value is 7.6, the peak characteristic number I is 2, and A (1) is 2.3.

The polymer (b) is ethylene-α-
Olefin-non-conjugated polyene copolymer, ethylene / α
-Olefin ratio (molar ratio) 86/14, ethylene / propylene / non-conjugated polyene ratio (molar ratio) 82.8 / 1
3.8 / 3.4, the total (mol%) of propylene and non-conjugated polyene is 17.2, A is 0.3, and the intrinsic viscosity is 1.6.
5 dl / g, DSC melting peak temperature is 40 ° C., and DSC heat of fusion is 1.6 cal / g.

The polymers (a) and (b) employ propylene as the α-olefin and 5-ethylidene-2-norbornene as the non-conjugated polyene.

The physical properties of the composition according to this example were evaluated,
The results are shown in Table 2.

The compound viscosity is measured according to JIS K 6
The vulcanized composition was evaluated according to JIS K 6251 and JIS K 6253. The flame retardancy was evaluated according to JIS K 7201 and UL-94V.

The evaluation criteria for UL-94V are based on the following.

94V-0: Extinction time after flame contact is 10 seconds or less. The total extinction time after 10 flame contact is 50 seconds or less. No drip property. The sample must not be burnt completely, the debris should disappear within 30 seconds after removing the flame.

94V-1: Extinction time of 30 seconds or less after removing the flame. The total extinction time after contact with flames 10 times is 250
Less than a second. Remaining dust time is 60 seconds or less, otherwise the same as 94V-0.

94V-2: Surgical absorbent cotton burns due to drip. Others are the same as 94V-1.

Extrusion processability is evaluated according to ASTM D223
It carried out according to 0-90. The evaluation criteria are based on ASTM D 2230 scoring method B using ASTM Garb die.

Scoring method B: In the extrudate, the sharpness and continuity of the 30 ° edge are 10 points at the maximum, 1 point at the minimum, and the smoothness of the surface skin is the maximum A and the minimum E, and the numbers and alphabets are combined and scored and displayed. To do. (Example 2) The rubber composition according to Example 2 is the same as Example 1 except that the copolymer is composed only of the polymer (a).
It has the same compounding composition as the rubber composition according to. That is, with respect to 100 parts by weight of the polymer (a), 5 parts by weight of tricresyl phosphate, 150 parts by weight of aluminum hydroxide, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid,
2 parts by weight of silane coupling agent, 5 parts by weight of carbon black (MAF grade), 10 parts by weight of paraffin oil, 1.5 parts by weight of sulfur, and 1.5 parts by weight of BZ as a vulcanization accelerator. Parts, 1 part by weight of CZ and TRA, and 1.5 parts by weight of TT were added, and the mixture was kneaded and then molded to obtain a rubber composition according to this example. The physical properties of the composition were evaluated, and the results are shown in Table 2. The physical properties are evaluated by the same method as the physical properties evaluation method for the rubber composition according to Example 1. (Example 3) The rubber composition according to Example 3 was prepared in the same manner as in Example 1 except that the copolymer was composed only of the polymer (b).
It has the same compounding composition as the rubber composition according to. That is, with respect to 100 parts by weight of the polymer (b), 5 parts by weight of tricresyl phosphate, 150 parts by weight of aluminum hydroxide, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid,
2 parts by weight of silane coupling agent, 5 parts by weight of carbon black (MAF grade), 10 parts by weight of paraffin oil, 1.5 parts by weight of sulfur, and 1.5 parts by weight of BZ as a vulcanization accelerator. Parts, 1 part by weight of CZ and TRA, and 1.5 parts by weight of TT were added, and the mixture was kneaded and then molded to obtain a rubber composition according to this example. The physical properties of the composition were evaluated, and the results are shown in Table 2. The physical properties are evaluated by the same method as the physical properties evaluation method for the rubber composition according to Example 1. (Comparative Example 1) The rubber composition according to Comparative Example 1 is the same as the rubber composition according to Example 1 except that the copolymer is composed only of the polymer (C) and no phosphorus-based flame retardant is added. It is a blended composition. That is, with respect to 100 parts by weight of the polymer (c), 150 parts by weight of aluminum hydroxide, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 2 parts by weight of silane coupling agent, carbon black (MAF grade).
5 parts by weight, 10 parts by weight of paraffin oil, and 1.5 parts by weight of sulfur, and as a vulcanization accelerator, 1.5 parts by weight of BZ, 1 part by weight of CZ and TRA, and TT of 1. A rubber composition according to this comparative example was obtained by adding 5 parts by weight, kneading, and then molding. The physical properties of the composition were evaluated, and the results are shown in Table 2. The physical properties are evaluated by the same method as the physical properties evaluation method for the rubber composition according to Example 1.

The polymer (c) is an ethylene-α-olefin-non-conjugated polyene copolymer, and is ethylene / α-
Olefin ratio (molar ratio) is 74/26, non-conjugated polyene weight% is 7.9, intrinsic viscosity is 1.38 dl / g, Mooney viscosity (ML _{1 + 4} 100 ° C.) = 34, GPC Q value is 1.
The peak characteristic number I is 1.8 and A (1) is 3.1. As in Example 1, propylene is used as the α-olefin and 5-ethylidene-2-norbornene is used as the non-conjugated polyene. (Comparative Example 2) The rubber composition according to Comparative Example 2 was the same as that of Comparative Example 1 except that the compounding ratio of aluminum hydroxide to the polymer (C) was changed and clay was compounded as an inorganic filler. It has the same compounding composition as the rubber composition. That is, with respect to 100 parts by weight of the polymer (c), 50 parts by weight of aluminum hydroxide, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 2 parts by weight of silane coupling agent, carbon black (MAF grade). 5 parts by weight, 90 parts by weight of clay, 10 parts by weight of paraffin oil, 1.5 parts by weight of sulfur, and 1.5 parts by weight of BZ, 1 part by weight of CZ and TRA as vulcanization accelerators. Then, 1.5 parts by weight of TT was added, and the mixture was kneaded and then molded to obtain a rubber composition according to this comparative example. The physical properties of the composition were evaluated, and the results are shown in Table 2. The physical properties are evaluated by the same method as the physical properties evaluation method for the rubber composition according to Example 1.

[0056]

[Table 2]

As is clear from the results in Table 2, according to the rubber compositions according to the examples satisfying the requirements of the present invention, the oxygen index and the UL-94V are high values (94V-2 or more), that is, high flame retardancy. Of the rubber composition according to the comparative example, while exhibiting excellent extrusion processability (6A to 9A based on ASTM D 2230-90, extrudability evaluation scoring criteria B), It can be confirmed that although the flame retardancy is almost the same as that of the example, the extrusion processability is inferior. Further, from the results of Example 2, the rubber composition according to the example shows not only high flame retardancy but also extremely good processability (roll processability, extrusion processability) and further physical properties of tensile strength. It can be confirmed that it is excellent. The results of Example 3 show that the rubber composition according to Example 3 is rich in elastic properties with respect to possible deterioration of physical properties by incorporating a flame-retardant material in addition to high flame retardancy, and It can be confirmed that the vulcanized rubber has a sufficiently high strength.

Therefore, the rubber composition according to the present invention can provide a flame-retardant rubber composition for extrusion, which is excellent in cost performance, flame retardancy and processability. Was done.

In the present invention, only the described embodiments have been described in detail, but it is apparent to those skilled in the art that various variations and modifications are possible within the scope of the technical idea of the present invention. It is obvious that such variations and modifications belong to the scope of the claims.

[0060]

As is apparent from the above description, the present invention has the following effects.

According to the rubber composition of the present invention, it is possible to provide a flame-retardant rubber composition for extrusion and a sealing material, which are excellent in cost performance, flame retardancy and processability. In particular, since the present invention uses a non-halogen flame retardant, there is no concern that the environment will be polluted.

Further, by blending the above-mentioned copolymer (a), in addition to high flame retardancy, it exhibits extremely good processability (roll processability, extrusion processability) and further has excellent tensile strength physical properties. It is possible to provide a flame-retardant rubber composition for extrusion and a sealing material.

Further, by blending the copolymer (b), in addition to high flame retardancy, blending a flame retardant material has rich elastic properties against possible deterioration of physical properties, Further, it is possible to provide a flame-retardant rubber composition for extrusion and a sealing material which have sufficiently high vulcanized rubber strength and meet high performance requirements.

The rubber composition according to the present invention can be effectively used particularly as a sealing material for building materials, railway vehicles or automobiles.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Junichi Koshiba             Sumitomo Chemical Co., Ltd. 1-5 Anezaki Kaigan, Ichihara City, Chiba Prefecture             Business F-term (reference) 4J002 BB05W BB05X BB15W BB15X                       DE066 DE076 DE086 DE126                       DE146 DE286 EW046 FD010                       FD136 GJ02                 4J100 AA02P AA03Q AA04Q AA07Q                       AA16Q AA17Q AA19Q AA21Q                       AR16R AR18R AR21R AR22R                       AR25R AS11R CA04 CA05                       DA04 DA05 DA09 DA22 DA24                       JA28

Claims (5)

[Claims] 1. An ethylene-α-olefin-non-conjugated polyene copolymer, which is the following (a) or (b), and a non-halogen flame retardant, and is extrudable (ASTM).
-D-2230-90, scoring criteria B) is 6A to 10A, a flame-retardant rubber composition for extrusion. (A) The ethylene / α-olefin ratio (molar ratio) is 4
0/60 to 95/5, 0 to 25% by weight of non-conjugated polyene, and an intrinsic viscosity of 0.
The Q value (weight average molecular weight / number average molecular weight) measured by GPC is 4 to 20 at 8 to 5.0 dl / g, and the peak characteristic numbers I and A (1) obtained from the molecular weight distribution curve are I ≧
2 and ethylene-α- with 1.5 ≦ A (1) ≦ 3.0
Olefin-non-conjugated polyene copolymer. (B) The ethylene / α-olefin ratio (molar ratio) is 8
In 3/17 to 97/3, the sum of α-olefin and non-conjugated polyene is 6 to 19 mol%, A obtained from the following formula is A ≧ 0.1, A = (42P + 120D) / (42P + 120D + 28
E) P: content of α-olefin in copolymer rubber (mol%) D: content of non-conjugated polyene (mol%) E: content of ethylene (mol%) Intrinsic viscosity measured in 70 ° C. xylene , 0.8-4.
At 0 dl / g, melting peak temperature by DSC measurement is 70
An ethylene-α-olefin-non-conjugated polyene copolymer having a heat of fusion of 10 cal / g or less at a temperature of ℃ or less. 2. The flame-retardant rubber composition for extrusion according to claim 1, wherein the ethylene-α-olefin-nonconjugated polyene copolymer (a) and the ethylene-α-olefin-nonconjugated polyene copolymer (II) are used. ) And a flame-retardant rubber composition for extrusion. 3. The flame-retardant rubber composition for extrusion according to claim 2, wherein the ethylene-α-olefin-non-conjugated polyene copolymer (A) / ethylene-α-olefin-non-conjugated polyene copolymer (II) ) Ratio (weight ratio) is 5/95 to 95
A flame-retardant rubber composition for extrusion, characterized by being / 5. 4. The flame-retardant rubber composition for extrusion according to claim 1, wherein the non-halogen flame retardant is a phosphorus flame retardant, a metal oxide, or a hydrated metal oxide. A flame-retardant rubber composition for extrusion. 5. A sealing material comprising a flame-retardant extrusion rubber composition, wherein the flame-retardant extrusion rubber composition comprises:
4. A sealing material, which is the rubber composition according to 4.