EP0272071A1
Expired / Lapsed
EP
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Elastomeric compositions
Assignee: Balfour Beatty PLC
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Filing: 1987-12-14
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Granted: —
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Expires: 2007-12-14
Abstract
Abstract Elastomeric compositions that are halogen-free, flame retardant and resistant to fluids and suitable for sheathing cables to NES 518 comprise (in parts by weight): 40 - 65 parts of an EVA with a vinyl acetate content of at least 70%; 35 - 60 parts of a fully hydrogenated butadiene/acrylonitrile copolymer, making a total polymer content of 100 parts; 4 -10 parts of a plasticiser; 130 - 160 parts of a high-purity grade of alumina trihydrate filler with a BET surface area greater than 6 m²/g; 1 - 3 parts of a coupling agent for the filler; and a chemical curing agent in an amount sufficient to cross-link the polymer constituent but not sufficient to reduce the tear strength of the cured composition below a limit of 5N/mm.
Inventors
- 👤 Daljit Singh Ohbi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 13:14
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/44; H01B3/448; C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08L; C08L15/00; C08L15/005; C08L31/00; C08L31/02; C08L31/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
111 words
Halogen-free elastomeric composition comprising (in parts by weight): 40 to 65 parts of an EVA with a vinyl acetate content of more than 60%; 35 - 60 parts of a fully hydrogenated butadiene/acrylonitrile copolymer, making a total polymer content of 100 parts; 4 -10 parts of a plasticiser; 130 - 160 parts of a high-purity grade of alumina trihydrate filler with a BET surface area greater than 6 m²/g; 1 - 3 parts of a coupling agent for the filler; and a chemical curing agent in an amount sufficient to cross-link the polymer constituent but not sufficient to reduce the tear strength of the cured composition below a limit of 5N/mm/.
Claim 2
Dependent Claim
111 words
Halogen-free elastomeric composition comprising (in parts by weight): 40 to 65 parts of an EVA with a vinyl acetate content of more than 60%; 35 - 60 parts of a fully hydrogenated butadiene/acrylonitrile copolymer, making a total polymer content of 100 parts; 4 -10 parts of a plasticiser; 130 - 160 parts of a high-purity grade of alumina trihydrate filler with a BET surface area greater than 6 m²/g; 1 - 3 parts of a coupling agent for the filler; and a chemical curing agent in an amount sufficient to cross-link the polymer constituent but not sufficient to reduce the tear strength of the cured composition below a limit of 5N/mm/.
Claim 3
Dependent Claim
27 words
A composition as claimed in Claim 1 in which the filler gives, when tested according to the Appendix herein, a specific conductance of less that 100 µS.
Claim 4
Dependent Claim
23 words
A composition as claimed in Claim 1 or Claim 2 in which the filler has a BET surface area of at least 12m²/g.
Claim 5
Dependent Claim
24 words
A composition as claimed in any one of Claims 1 - 3 comprising two grades of alumina trihydrate of substantially different particle size/surface area.
Claim 6
Dependent Claim
23 words
A composition as claimed in any one of the preceding Claims in which the EVA has a vinyl acetate content of about 70%.
Claim 7
Dependent Claim
22 words
A composition as claimed in any one of the preceding claims in which the amount of EVA present is about 60 parts.
Claim 8
Dependent Claim
19 words
A composition as claimed in any one of the preceding claims in which the coupling agent is a silane.
Claim 9
Dependent Claim
22 words
A composition as claimed in any one of Claims 1 - 7 in which the coupling agent is vinyl tris (methoxyethoxy) silane.
Claim 10
Dependent Claim
28 words
A composition as claimed in any one of the preceding claims in which the curing agent comprises bis ( tert butylperoxy iso propyl) benzene in combination with triallylcyanurate.
Claim 11
Dependent Claim
15 words
An electric cable sheathed with the composition claimed in any one of the preceding Claims.
References Cited (Backward Citations)
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