Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Reexamination Certificate
2001-09-10
2003-03-18
Teskin, Fred (Department: 1713)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
C524S548000, C524S549000, C524S436000, C525S205000, C525S207000, C525S210000, C525S240000
Reexamination Certificate
active
06534586
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a flame-retardant rubber composition and a flame-retardant elastomer containing an olefin copolymer as a base, and particularly to a flame-retardant rubber composition from which an elastomer having excellent mechanical properties is provided even when a nonhalogenated flame retardant is contained in plenty, and a flame-retardant elastomer obtained therefrom.
2. Description of the Background Art
In a field of rubber, elastomers making use of a nonhalogenated flame retardant have been required from the viewpoint of environmental protection in recent years.
A hydrous compound is generally used as a nonhalogenated flame retardant, and it is necessary to incorporate the hydrous compound in a comparatively great amount in order to achieve sufficient flame retardancy in an elastomer. However, an elastomer containing the hydrous compound in a high proportion involves a problem that the mechanical strength of the elastomer is deteriorated.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a flame-retardant rubber composition which may form a vulcanizate of an elastomer whose deterioration of mechanical strength is little to enjoy excellent mechanical properties, even when a nonhalogenated flame retardant is contained in a high proportion in the composition.
Another object of the present invention is to provide a flame-retardant elastomer, a vulcanized product, whose deterioration of mechanical strength is little to enjoy excellent mechanical properties even when a nonhalogenated flame retardant is contained in a high proportion.
According to the present invention, the following flame-retardant rubber compositions are provided, whereby the first object of the present invention is achieved.
1. A flame-retardant rubber composition comprising:
(A) an olefin copolymer having a functional group, which comprises (a-1) a structural unit derived from ethylene, (a-2) a structural unit derived from an &agr;-olefin compound having 3 to 10 carbon atoms, (a-3) a structural unit derived from a functional group-containing unsaturated compound, and optionally (a-4) a structural unit derived from a nonconjugated diene compound, and has an intrinsic viscosity |&eegr;| of 0.1 to 10 dL/g as measured in decalin® (decahydronaphthalene) at 135° C.;
(B) a vulcanizing agent and/or a crosslinking agent; and
(C) a nonhalogenated flame retardant.
2. A flame-retardant rubber composition according to the item 1, wherein the functional group-containing unsaturated compound, from which the structural unit (a-3) in the olefin copolymer (A) having the functional group is derived, is a compound represented by the following formula (1) and/or the following formula (2): Formula (1):
CH═CR
1
—(CH
2
)
n
—X
wherein R
1
means a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, X denotes a functional group represented by —OR
2
, —COOH, —NHR
2
or —CONHR
2
(R
2
being a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms), and n is an integer of 0 to 6;
wherein R
3
means a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, Y
1
, Y
2
and Y
3
denote, independently of one another, a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a functional group represented by —OR
2
,—COOH, —NHR
2
or —CONHR
2
(R
2
being a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms), at least one of Y
1
, Y
2
and Y
3
is the functional group, at least two of Y
1
, Y
2
and Y
3
may be an acid anhydride group (—CO—O—CO—) or an imide group (—CO—NH—CO—) formed by being bonded to each other when they are the functional groups, p is an integer of 0 to 2, and q is an integer of 0 to 5.
3. A flame-retardant rubber composition according to the item 2, wherein the functional group X in the formula (1) or said at least one functional group of Y
1
, Y
2
and Y
3
in the formula (2) is a —COOH group.
4. A flame-retardant rubber composition according to any one of the items 1 to 3, wherein in the olefin copolymer (A) having the functional group, proportions of the structural unit (a-1), the structural unit (a-2), the structural unit (a-3) and the structural unit (a-4) are 35 to 90 mol %, 5 to 50 mol %, 0.01 to 5 mol % and 0 to 10 mol %, respectively.
5. A flame-retardant rubber composition according to any one of the items 1 to 4, which further comprises (D) an ethylene.&agr;-olefin copolymer having no functional group.
6. A flame-retardant rubber composition according to any one of the items 1 to 5, wherein the nonhalogenated flame retardant (C) is contained in a proportion of at least 5 parts by mass per 100 parts by mass in total of the olefin copolymer (A) having the functional group and the ethylene.&agr;-olefin copolymer (D) having no functional group.
According to the present invention, a flame-retardant elastomer obtained by subjecting the flame-retardant rubber composition according to any one of the items 1 to 6 to a vulcanizing treatment is provided, whereby the second object of the present invention is achieved.
According to the flame-retardant rubber compositions, the olefin copolymer, which is an elastomer-forming component, has the functional group in its structural unit, whereby the coexisting nonhalogenated flame retardant is chemically stabilized. Therefore, the degree of deterioration of mechanical strength in the resultant elastomers, which is caused by the nonhalogenated flame retardant, becomes little even when the nonhalogenated flame retardant is incorporated in a high proportion, so that the elastomers can be provided as those having high flame retardancy and excellent mechanical properties.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiments of the present invention will hereinafter be described in detail.
The flame-retardant rubber compositions according to the present invention comprise, as essential components the following components (A), (B) and (C).
The component (A) is an olefin copolymer having a functional group, which contains (a-1) a structural unit (hereinafter may also be referred to as “structural unit (a-1)”) derived from ethylene, (a-2) a structural unit (hereinafter may also be referred to as “structural unit (a-2)”) derived from an &agr;-olefin compound having 3 to 10 carbon atoms, (a-3) a structural unit (hereinafter may also be referred to as “structural unit (a-3)”) derived from a functional group-containing unsaturated compound, and optionally (a-4) a structural unit (hereinafter may also be referred to as “structural unit (a-4)”) derived from a nonconjugated diene compound, and has an intrinsic viscosity [&eegr;] of 0.1 to 10 dL/g as measured in decalin at 135° C.
The component (B) is a vulcanizing agent and/or a crosslinking agent.
The component (C) is a nonhalogenated flame retardant.
The flame-retardant rubber compositions according to the present invention may contain an ethylene.&agr;-olefin copolymer having no functional group as a component (D) within limits not impeding the objects of the present invention.
In the olefin copolymer (A) having the functional group used in the present invention, the structural unit (a-1) derived from ethylene is preferably contained in a range of 35 to 90 mol %, more preferably 40 to 85 mol %, particularly preferably 45 to 80 mol %, based on the whole structural unit in the component (A).
If the proportion of the structural unit (a-1) contained is lower than 35 mol %, it is difficult to copolymerize a functional group-containing cycloolefin represented by the formula (2), which is suitable for use in forming the structural unit (a-3), because the proportion of ethylene copolymerized for preparing the olefin copolymer (A) is too low. As a result, it is difficult to obtain an olefin copolymer (A) having a suitable functional group, and moreover an elastomer finally obtained from the resulting copolymer may be deteriorated in mechanical strength and abrasion resistance in some cases.
On the other hand, if the proportion of the structural unit
Ayukawa Junji
Hayakawa Toshiyuki
Tanaka Minoru
Tsuji Shoei
Tsutsumi Fumio
JSR Corporation
Teskin Fred
LandOfFree
Flame-retardant rubber composition and flame-retardant... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Flame-retardant rubber composition and flame-retardant..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flame-retardant rubber composition and flame-retardant... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3008966