EP2401329A1 - A fire performance material, and cable including the material - Google Patents

A fire performance material, and cable including the material

Info

Publication number
EP2401329A1
EP2401329A1 EP10719380A EP10719380A EP2401329A1 EP 2401329 A1 EP2401329 A1 EP 2401329A1 EP 10719380 A EP10719380 A EP 10719380A EP 10719380 A EP10719380 A EP 10719380A EP 2401329 A1 EP2401329 A1 EP 2401329A1
Authority
EP
European Patent Office
Prior art keywords
filler
weight
caco
parts
polymer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10719380A
Other languages
German (de)
French (fr)
Inventor
Graeme Alexander
Nick Rigopoulos
Donavan Marney
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nexans SA
Original Assignee
Nexans SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2009900820A external-priority patent/AU2009900820A0/en
Application filed by Nexans SA filed Critical Nexans SA
Publication of EP2401329A1 publication Critical patent/EP2401329A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/60—Additives non-macromolecular
    • C09D7/61—Additives non-macromolecular inorganic
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L83/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
    • C08L83/04—Polysiloxanes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D183/00—Coating compositions based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon, with or without sulfur, nitrogen, oxygen, or carbon only; Coating compositions based on derivatives of such polymers
    • C09D183/04—Polysiloxanes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/18—Fireproof paints including high temperature resistant paints
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H01B3/46—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes silicones
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B7/00—Insulated conductors or cables characterised by their form
    • H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
    • H01B7/29—Protection against damage caused by extremes of temperature or by flame
    • H01B7/295—Protection against damage caused by extremes of temperature or by flame using material resistant to flame
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/24—Acids; Salts thereof
    • C08K3/26—Carbonates; Bicarbonates

Definitions

  • This invention relates to a fire performance composition or material, a cable insulated with the material, and to a method of manufacturing a cable using the composition.
  • the invention is particularly suited for use in fire resistant cables and other applications where composition is required to maintain physical and/or electrical characteristics during and after exposure to fire.
  • Additives can include aluminium hydroxide, as discussed in US6043309 (Dow Corning) which is addressed to improvements in the extrusion properties and viscosity of silicone with aluminium hydroxide.
  • GB2016307 discloses a mineral insulated electrical cable having a water repellent filling.
  • Such cables consist of an electrical conductor contained in a hollow metal jacket, with a powdered filler material contained between the conductor and the jacket.
  • the filler can include a silicone material.
  • This document does not disclose a cable jacket material having a flexible jacket of silicone with a filler material blended into the silicone jacket material. The powdered filler cannot be applied by extrusion.
  • EP0283132 discloses a mineral insulated electrical cable having a filling which included flame retardant and water repellent characteristics.
  • the structure of these cables is an electrical conductor contained in a metal jacket, with the filler material in powdered form and compacted between the conductor and the jacket.
  • the powder filler can include, among other materials, CaCO 3 in proportions of up to about 5%, and the water resistant material can be, among other materials, silicone in either a liquid or powder form.
  • the CaCO 3 is included for the purpose of generating CO 2 .
  • This document does not disclose a cable jacket material having a flexible jacket of silicone with a filler material blended into the jacket material. The low proportion of CaCO 3 would not permit the formation of a useful or significant post-combustion residue.
  • EP0708455 discloses a flame resistant material including an organosilicon polymer with a ceramizable filler material.
  • This specification describes a number of ceramizable fillers or glassformers, being a material that has the property of being able to form a glass, or an amorphous liquid with very high viscosity at room temperature but with low viscosity at high temperatures as seen in a fire.
  • Additional auxiliary fillers such as CaCO 3 , among others, are also disclosed, for use in addition to the ceramizable filler. The purpose or function of these additional fillers is not disclosed.
  • Ceramizable fillers are an essential component of EP0708455.
  • the specification states that the organosilicon material needs to be compatible with the ceramizable filler.
  • the specification discloses between 50 and 300 parts by weight of ceramizable filler per 100 parts by weight of polymer. An upper limit of 500 parts by weight of ceramizable and non-ceramizable filler is disclosed.
  • the EP0708455 specification indicates that materials according to the invention all contain a ceramizable composition in the proportions set out above, the purpose being to produce a post-combustion ceramic layer on the wires. However, EP0708455 discloses only a material with amounts of ceramizable filler sufficient to form an insulative layer.
  • EP0708455 does not disclose or suggest a material without any ceramizable filler or with amounts of ceramizable filler insufficient to form a useful insulation layer.
  • the minimum amount of ceramizable filler disclosed is 50 parts by weight of ceramizable filler to 100 parts by weight of polymer.
  • the invention is predicated, at least in part, on the inventor's insight that certain compounds of calcium, silicone, and oxygen have high electrical resistivity. In addition, at least some of such compounds may also have good mechanical properties such as strength, cohesiveness and adhesion to metal.
  • a fire performance material including a polymer (1.006) including silicone polymer, and CaCO 3 filler (1.004), wherein the CaCO 3 filler is present in the material in an amount to leave a post- combustion residue after exposure of said material to fire, the material including less than 50 parts by weight of ceramizable filler to 100 parts by weight of polymer.
  • the post-combustion residue can be an insulating residue or a protective residue.
  • the material can advantageously include less than 20 parts by weight of ceramizable filler, preferably less than 10 parts by weight of ceramizable filler, preferably less than 5 parts by weight of ceramizable filler, and more preferably zero parts by weight of ceramizable filler.
  • the ceramizable filler defined in the background of the invention, can be those described in EP0708455.
  • not less than 92 weight % of the material can be made up Of CaCO 3 and polymer.
  • the fire performance material including at least 20 parts by weight CaCO 3 filler to 100 parts by weight of polymer.
  • the CaCO 3 filler can be up to 250 parts by weight to 100 parts by weight of polymer.
  • the filler can be in the range of 30 parts by weight to 70 parts by weight filler to 100 parts by weight polymer.
  • the silicone polymer of said fire performance material can be silicone elastomer.
  • the polymer can consist exclusively of silicone elastomer.
  • the fire performance material can further include a cross-linking agent.
  • the invention also includes a cable having a fire resistant layer made from the fire performance material. Said layer can be an insulating layer or a protective layer (jacket).
  • the insulating or protective layer can form a residue in the form of a post-combustion layer on a substrate.
  • Said substrate can be one or several metal conductor, and/or one or several insulated conductor.
  • the residue can include at least one compound including Ca and Si.
  • the residue can include at least one of: Wollastonite (CaSiOs), Calcium
  • Oxide (CaO), Larnite (Ca 2 (SiO 4 ), Calcite (CaCO 3 ), Calcium Silicate (Ca 2 SiO 4 ), Portlandite (Ca(OH) 2 ), SiO 2 (Hexagonal), and SiO 2 .
  • the post-combustion residue can adhere to the conductor.
  • the residue can be cohesive.
  • the fire performance material can be applied as a jacket or sub-layer on an electrical conductor.
  • the material can be used to provide a coating on cable conductors.
  • the coating can be an external jacket or an internal layer.
  • the invention also provides a method of manufacturing a cable according to claim 11 including the steps of: mixing CaCO 3 filler (1.004) with the polymer (1.006) to obtain a coating material; and extruding the coating material onto an electrical conductor (1.010) to form the fire resistant layer (1.014).
  • the material of the present invention has the surprising advantage that a residue with good post-combustion electrical resistance characteristics is formed with little or no other fillers, and especially with little or no ceramifying material. At the same time, the material is cheaper than silicone polymer or silicone polymer and ceramifying filler.
  • Figure 1 schematically illustrates the components of a cable coating system adapted to use the fire resistant material of the invention.
  • Figure 2 is a graphical representation of X-Ray Diffraction analysis of the post-combustion residue according to an embodiment of the invention.
  • Wollastonite As mentioned above, certain compounds of calcium, silicon, and oxygen, such as Wollastonite (CaSiOs), have good electrical resistivity. Wollastonite has a melting point in excess of 1500 0 C.
  • the invention derives in part from the inventor's insight that such compounds may be formed during combustion by providing potential precursor material for calcium oxide and silica from silicone decomposition.
  • the inventor deduced that a mixture of silicone and CaCO 3 in the presence of fire can produce the CaO and silica, which would then become available to form the target compounds during the fire.
  • the inventor further reasoned that the mechanical properties of such combustion products could be sufficient to provide an insulative or protective residue which has adequate mechanical properties such that ceramic forming fillers were thus superfluous at least for some applications.
  • one embodiment of the invention provides a fire resistant material including a mixture of silicone polymer and CaCO 3 , the CaCO 3 being present in the mixture in an amount to leave an insulating or protective layer on a substrate such as an electrical conductor.
  • Products of the exposure of the mixture of silicone elastomer and CaCO 3 can include one or more of the following: Wollastonite (CaSiO 3 ), Calcium Oxide (CaO), Larnite (Ca 2 (SiO 4 ), Calcite (CaCO 3 ), Calcium Silicate (Ca 2 SiO 4 ), Portlandite (Ca(OH) 2 ), SiO 2 (Hexagonal), and SiO 2 (Rhombo. H. axes) in a mix of crystalline and amorphous forms.
  • the resulting post-combustion residue provides surprisingly good electrical properties at temperatures of the order of 1000 0 C.
  • Figure 1 schematically illustrates the components of a cable coating system adapted to use the fire resistant material of the invention.
  • the system includes a supply OfCaCO 3 1.004, a supply of silicone elastomer 1.006, a mixer 1.008, and an extruder head 1.012.
  • the CaCO 3 and silicone elastomer are mixed in the mixer 1.008 in a predetermined ratio to provide an extrudable composition and fed to the extruder 1.012.
  • a single electrical conductor, or a bundle of electrical conductors, 1.010 is drawn through the extruder head and coated with the mixture.
  • the mixture is such as to form an electrical insulating layer 1.014 on the conductor, the insulating layer having adequate mechanical properties to permit the handling, installation and use of the cable, and such that, after exposure to fire, the combustion products of the mixture will form an electrically resistive or insulative residue layer to maintain electrical functionality of the cable.
  • An additional external jacket can be extruded over the layer of fire resistant material to provide additional strength or insulation if required.
  • composition was prepared by adding CaCO 3 (Omyacarb 2T) (50/50 wt% basis) to Wacker R401/80S silicone elastomer with 2% Perkadox 14-40 peroxide.
  • composition was extruded at 0.8 mm wall thickness onto 7/0.50 mm bunched plain annealed copper wire and air oven cured at 190°C/2hrs.
  • the coated wire was twisted with another coated wire and subjected to a fast rising temperature in a tube furnace while measuring the resistance between the twisted wires.
  • a powder sample of the residue was subjected to X-Ray Diffraction analysis to determine its phase composition.
  • a Bruker D8 Advance X-ray Diffractometer with CuK 0 - radiation (4OkV, 4OmA) monochromatised with a graphite sample monochromator was employed to determine the X-ray diffraction (XRD) pattern.
  • the sample was scanned over the 2-theta range 5° to 85° with a step size of 0.02° and a count time of 4 seconds per step. Analyses were performed on the collected XRD data for the sample using the Bruker XRD search match program EVATM.
  • Figure 2 illustrates X-Ray Diffraction analysis results for the residue from mixture according to an embodiment of the invention. Peaks can be seen for Larnite, Wollastonite, CaO (Face Centred), and Calcite.
  • An advantage of the present invention is that silicone can be heavily loaded with CaCO 3 .
  • a range of 20% to 70% CaCO 3 and 80% to 30% silicone may be possible.
  • Both the pre-combustion mixture and the post-combustion residue have good electrical insulative properties.
  • the post combustion residue also has good adhesion to the conductor and good mechanical strength.
  • the residue layer can also serve to protect the conductor from water.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Insulated Conductors (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)

Abstract

A fire resistant material including an extrudable mixture of an silicone elastomer or polymer 1.006 including silicone and CaCO3 filler 1.004, the CaCO3 filler being present in the mixture in an amount to leave an insulating or protective layer 1.012 on a substrate such as an electrical conductor 1.010. The material contains no more than 50 parts by weight of ceramizable or glassforming filler to 100 parts by weight polymer. The silicone polymer and CaCO3 in combination preferably form more than 92% of the material. When used as a layer or jacket for a cable, the mixture decomposes on exposure to fire to provide a protective or electrically insulative layer on the conductor.

Description

A fire performance material, and cable including the material
Field of the invention
[001] This invention relates to a fire performance composition or material, a cable insulated with the material, and to a method of manufacturing a cable using the composition.
[002] The invention is particularly suited for use in fire resistant cables and other applications where composition is required to maintain physical and/or electrical characteristics during and after exposure to fire.
Background of the invention
[003] Flame retardant cable jackets are known in which additives are added to the plastics material to counter the fire by producing, for example, water or carbon dioxide. Additives can include aluminium hydroxide, as discussed in US6043309 (Dow Corning) which is addressed to improvements in the extrusion properties and viscosity of silicone with aluminium hydroxide.
[004] GB2016307 (AEI) discloses a mineral insulated electrical cable having a water repellent filling. Such cables consist of an electrical conductor contained in a hollow metal jacket, with a powdered filler material contained between the conductor and the jacket. The filler can include a silicone material. This document does not disclose a cable jacket material having a flexible jacket of silicone with a filler material blended into the silicone jacket material. The powdered filler cannot be applied by extrusion.
[005] EP0283132 (AEI) discloses a mineral insulated electrical cable having a filling which included flame retardant and water repellent characteristics. The structure of these cables is an electrical conductor contained in a metal jacket, with the filler material in powdered form and compacted between the conductor and the jacket. The powder filler can include, among other materials, CaCO3 in proportions of up to about 5%, and the water resistant material can be, among other materials, silicone in either a liquid or powder form. The CaCO3 is included for the purpose of generating CO2. This document does not disclose a cable jacket material having a flexible jacket of silicone with a filler material blended into the jacket material. The low proportion of CaCO3 would not permit the formation of a useful or significant post-combustion residue.
[006] EP0708455 (Datwyler) discloses a flame resistant material including an organosilicon polymer with a ceramizable filler material. This specification describes a number of ceramizable fillers or glassformers, being a material that has the property of being able to form a glass, or an amorphous liquid with very high viscosity at room temperature but with low viscosity at high temperatures as seen in a fire. Additional auxiliary fillers, such as CaCO3, among others, are also disclosed, for use in addition to the ceramizable filler. The purpose or function of these additional fillers is not disclosed. Ceramizable fillers are an essential component of EP0708455. At [4,7] the specification states that the organosilicon material needs to be compatible with the ceramizable filler. The specification discloses between 50 and 300 parts by weight of ceramizable filler per 100 parts by weight of polymer. An upper limit of 500 parts by weight of ceramizable and non-ceramizable filler is disclosed. The EP0708455 specification indicates that materials according to the invention all contain a ceramizable composition in the proportions set out above, the purpose being to produce a post-combustion ceramic layer on the wires. However, EP0708455 discloses only a material with amounts of ceramizable filler sufficient to form an insulative layer. EP0708455 does not disclose or suggest a material without any ceramizable filler or with amounts of ceramizable filler insufficient to form a useful insulation layer. The minimum amount of ceramizable filler disclosed is 50 parts by weight of ceramizable filler to 100 parts by weight of polymer.
[007] It is also known to wrap mica impregnated tapes around a conductor to improve its fire resistance. However, this process is slow and costly.
[008] It is desirable to provide a fire performance material and a fire performance cable which is simple and cost effective to manufacture.
Summary of the invention
[009] The invention is predicated, at least in part, on the inventor's insight that certain compounds of calcium, silicone, and oxygen have high electrical resistivity. In addition, at least some of such compounds may also have good mechanical properties such as strength, cohesiveness and adhesion to metal.
[010] According to one embodiment of the invention a fire performance material including a polymer (1.006) including silicone polymer, and CaCO3 filler (1.004), wherein the CaCO3 filler is present in the material in an amount to leave a post- combustion residue after exposure of said material to fire, the material including less than 50 parts by weight of ceramizable filler to 100 parts by weight of polymer.
[Oi l] The post-combustion residue can be an insulating residue or a protective residue.
[012] The material can advantageously include less than 20 parts by weight of ceramizable filler, preferably less than 10 parts by weight of ceramizable filler, preferably less than 5 parts by weight of ceramizable filler, and more preferably zero parts by weight of ceramizable filler.
[013] The ceramizable filler, defined in the background of the invention, can be those described in EP0708455.
[014] In one embodiment, not less than 92 weight % of the material can be made up Of CaCO3 and polymer.
[015] According to another embodiment of the invention, the fire performance material including at least 20 parts by weight CaCO3 filler to 100 parts by weight of polymer.
[016] The CaCO3 filler can be up to 250 parts by weight to 100 parts by weight of polymer.
[017] Preferably, the filler can be in the range of 30 parts by weight to 70 parts by weight filler to 100 parts by weight polymer.
[018] The silicone polymer of said fire performance material can be silicone elastomer.
[019] The polymer can consist exclusively of silicone elastomer.
[020] The fire performance material can further include a cross-linking agent. [021] The invention also includes a cable having a fire resistant layer made from the fire performance material. Said layer can be an insulating layer or a protective layer (jacket).
[022] On exposure to flame, the insulating or protective layer can form a residue in the form of a post-combustion layer on a substrate. Said substrate can be one or several metal conductor, and/or one or several insulated conductor.
[023] The residue can include at least one compound including Ca and Si.
[024] The residue can include at least one of: Wollastonite (CaSiOs), Calcium
Oxide (CaO), Larnite (Ca2(SiO4), Calcite (CaCO3), Calcium Silicate (Ca2SiO4), Portlandite (Ca(OH)2), SiO2 (Hexagonal), and SiO2.
[025] The post-combustion residue can adhere to the conductor.
[026] The residue can be cohesive.
[027] The fire performance material can be applied as a jacket or sub-layer on an electrical conductor.
[028] The material can be used to provide a coating on cable conductors.
[029] The coating can be an external jacket or an internal layer.
[030] The invention also provides a method of manufacturing a cable according to claim 11 including the steps of: mixing CaCO3 filler (1.004) with the polymer (1.006) to obtain a coating material; and extruding the coating material onto an electrical conductor (1.010) to form the fire resistant layer (1.014).
[031] The material of the present invention has the surprising advantage that a residue with good post-combustion electrical resistance characteristics is formed with little or no other fillers, and especially with little or no ceramifying material. At the same time, the material is cheaper than silicone polymer or silicone polymer and ceramifying filler. Brief description of the drawings
[032] An embodiment or embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
[033] Figure 1 schematically illustrates the components of a cable coating system adapted to use the fire resistant material of the invention.
[034] Figure 2 is a graphical representation of X-Ray Diffraction analysis of the post-combustion residue according to an embodiment of the invention.
[035] The numbering convention used in the drawings is that the digits in front of the full stop indicate the drawing number, and the digits after the full stop are the element reference numbers. Where possible, the same element reference number is used in different drawings to indicate corresponding elements.
Detailed description of the embodiment or embodiments
[036] The invention will be described in the context of a cable coated with material according to an embodiment of the invention, and with reference to the drawings.
[037] As mentioned above, certain compounds of calcium, silicon, and oxygen, such as Wollastonite (CaSiOs), have good electrical resistivity. Wollastonite has a melting point in excess of 15000C.
[038] The invention derives in part from the inventor's insight that such compounds may be formed during combustion by providing potential precursor material for calcium oxide and silica from silicone decomposition. The inventor deduced that a mixture of silicone and CaCO3 in the presence of fire can produce the CaO and silica, which would then become available to form the target compounds during the fire. The inventor further reasoned that the mechanical properties of such combustion products could be sufficient to provide an insulative or protective residue which has adequate mechanical properties such that ceramic forming fillers were thus superfluous at least for some applications. [039] Accordingly, one embodiment of the invention provides a fire resistant material including a mixture of silicone polymer and CaCO3, the CaCO3 being present in the mixture in an amount to leave an insulating or protective layer on a substrate such as an electrical conductor.
[040] Products of the exposure of the mixture of silicone elastomer and CaCO3 can include one or more of the following: Wollastonite (CaSiO3), Calcium Oxide (CaO), Larnite (Ca2(SiO4), Calcite (CaCO3), Calcium Silicate (Ca2SiO4), Portlandite (Ca(OH)2), SiO2 (Hexagonal), and SiO2 (Rhombo. H. axes) in a mix of crystalline and amorphous forms. The resulting post-combustion residue provides surprisingly good electrical properties at temperatures of the order of 10000C.
[041] Figure 1 schematically illustrates the components of a cable coating system adapted to use the fire resistant material of the invention.
[042] The system includes a supply OfCaCO3 1.004, a supply of silicone elastomer 1.006, a mixer 1.008, and an extruder head 1.012.
[043] The CaCO3 and silicone elastomer are mixed in the mixer 1.008 in a predetermined ratio to provide an extrudable composition and fed to the extruder 1.012. A single electrical conductor, or a bundle of electrical conductors, 1.010 is drawn through the extruder head and coated with the mixture. The mixture is such as to form an electrical insulating layer 1.014 on the conductor, the insulating layer having adequate mechanical properties to permit the handling, installation and use of the cable, and such that, after exposure to fire, the combustion products of the mixture will form an electrically resistive or insulative residue layer to maintain electrical functionality of the cable.
[044] An additional external jacket can be extruded over the layer of fire resistant material to provide additional strength or insulation if required.
[045] Example 1
[046] A sample consisting of CaCO3 (Omyacarb 2T) to Wacker R401/80S silicone elastomer (50/50 wt% basis) with 2% Perkadox 14-40 peroxide as a cross-linking agent was prepared and subjected to controlled heating, the resulting residue was then analysed.
[047] The composition was prepared by adding CaCO3 (Omyacarb 2T) (50/50 wt% basis) to Wacker R401/80S silicone elastomer with 2% Perkadox 14-40 peroxide.
[048] The composition was extruded at 0.8 mm wall thickness onto 7/0.50 mm bunched plain annealed copper wire and air oven cured at 190°C/2hrs.
[049] The coated wire was twisted with another coated wire and subjected to a fast rising temperature in a tube furnace while measuring the resistance between the twisted wires.
[050] The results show that the resistance at 10000C ranges between 0.5 MΩ and
1.13 MΩ. None of the Silicone-CaCO3 combinations resulted in a cable that had zero resistance ( i.e failed to 0 Ω) for the single layer.
[051] A powder sample of the residue was subjected to X-Ray Diffraction analysis to determine its phase composition. A Bruker D8 Advance X-ray Diffractometer with CuK0- radiation (4OkV, 4OmA) monochromatised with a graphite sample monochromator was employed to determine the X-ray diffraction (XRD) pattern. The sample was scanned over the 2-theta range 5° to 85° with a step size of 0.02° and a count time of 4 seconds per step. Analyses were performed on the collected XRD data for the sample using the Bruker XRD search match program EVA™.
[052] Crystalline phases were identified using the ICDD-JCPDS powder diffraction database. A variety of phases were identified as shown in Figure 2.
[053] Analysis showed that heating of the CaCO3 and silicone to 10000C produces a number of compounds including Wollastonite (CaSiO3), Calcium Oxide (CaO), Larnite (Ca2(SiO4), Calcite (CaCO3), Calcium Silicate (Ca2SiO4), Portlandite (Ca(OH)2), SiO2 (Hexagonal), and SiO2 (Rhombo.H. axes) in a mix of crystalline and amorphous forms.
[054] Test showed that the residue exhibited resistivities between 0.5 MΩ and
1.13 MΩ . [055] Figure 2 illustrates X-Ray Diffraction analysis results for the residue from mixture according to an embodiment of the invention. Peaks can be seen for Larnite, Wollastonite, CaO (Face Centred), and Calcite.
[056] An advantage of the present invention is that silicone can be heavily loaded with CaCO3. A range of 20% to 70% CaCO3 and 80% to 30% silicone may be possible. This provides a cost advantage in that CaCO3 is significantly cheaper than silicone. Both the pre-combustion mixture and the post-combustion residue have good electrical insulative properties. The post combustion residue also has good adhesion to the conductor and good mechanical strength. The residue layer can also serve to protect the conductor from water.
[057] In this specification, reference to a document, disclosure, or other publication or use is not an admission that the document, disclosure, publication or use forms part of the common general knowledge of the skilled worker in the field of this invention at the priority date of this specification, unless otherwise stated.
[058] In this specification, terms indicating orientation or direction, such as
"up", "down", "vertical", "horizontal", "left", "right" "upright", "transverse" etc. are not intended to be absolute terms unless the context requires or indicates otherwise. These terms will normally refer to orientations shown in the drawings.
[059] Where ever it is used, the word "comprising" is to be understood in its
"open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear.
[060] It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative aspects of the invention.
[061] While particular embodiments of this invention have been described, it will be evident to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments and examples are therefore to be considered in all respects as illustrative and not restrictive, and all modifications which would be obvious to those skilled in the art are therefore intended to be embraced therein.

Claims

Claims
1. A fire performance material including a polymer (1.006) including silicone polymer, and CaCO3 filler (1.004), characterized in that the CaCO3 filler is present in the material in an amount to leave a post-combustion residue after exposure of said material to fire, the material including less than 50 parts by weight of ceramizable filler to 100 parts by weight of polymer.
2. A fire performance material as claimed in claim 1, characterized in that it includes at least 20 parts by weight CaCO3 filler to 100 parts by weight of polymer in the material.
3. A fire performance material as claimed in claim 1 or claim2, characterized in that the material has zero parts by weight of ceramizable filler.
4. A fire performance material as claimed in any one of the preceding claims, characterized in that it includes up to 250 parts by weight CaCO3 filler to 100 parts by weight of polymer in the material.
5. A fire performance material as claimed in any one of the preceding claims, characterized in that it includes a range of 30 parts by weight to 70 parts by weight CaCO3 filler to 100 parts by weight of polymer in the material.
6. A fire performance material as claimed in any one of the preceding claims, characterized in that the silicone polymer is silicone elastomer.
7. A fire performance material as claimed in any one of the preceding claims, characterized in that it further includes a cross-linking agent.
8. A fire performance material as claimed in any one of the preceding claims, characterized in that the residue includes at least one compound including Si and Ca.
9. A fire performance material as claimed in any one of the preceding claims, characterized in that the residue is cohesive.
10. A fire performance material as claimed in any one of the preceding claims, characterized in that not less than 92 weight % of the material is made up Of CaCO3 and polymer.
11. A cable having a fire resistant layer made from a fire performance material as claimed in any one of the preceding claims.
12. A method of manufacturing a cable according to claim 11, characterized in that the method includes the steps of: mixing CaCO3 filler (1.004) with the polymer (1.006) to obtain a coating material; and extruding the coating material onto an electrical conductor (1.010) to form the fire resistant layer (1.014).
14. A fire performance material substantially as herein described with reference to the accompanying drawings.
15. A cable substantially as herein described with reference to the accompanying drawings.
EP10719380A 2009-02-25 2010-02-25 A fire performance material, and cable including the material Withdrawn EP2401329A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2009900820A AU2009900820A0 (en) 2009-02-25 A Fire Performance Material, and Cable Including the Material
PCT/IB2010/000628 WO2010097705A1 (en) 2009-02-25 2010-02-25 A fire performance material, and cable including the material

Publications (1)

Publication Number Publication Date
EP2401329A1 true EP2401329A1 (en) 2012-01-04

Family

ID=42224715

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10719380A Withdrawn EP2401329A1 (en) 2009-02-25 2010-02-25 A fire performance material, and cable including the material

Country Status (4)

Country Link
EP (1) EP2401329A1 (en)
AU (1) AU2010217302A1 (en)
CA (1) CA2750512A1 (en)
WO (1) WO2010097705A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102250473B (en) * 2011-06-16 2012-07-25 刘立文 Modified cable coating composite material and preparation method thereof
ES2644323T3 (en) * 2013-11-28 2017-11-28 Nexans Flame retardant materials
US11359094B2 (en) 2020-01-08 2022-06-14 TE Connectivity Services Gmbh Silicone composite for high temperature applications
US12077706B2 (en) 2021-01-28 2024-09-03 TE Connectivity Services Gmbh Hybrid silicone composite for high temperature applications

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04202497A (en) * 1990-11-30 1992-07-23 Toshiba Silicone Co Ltd Fire-retardant silicone grease composition
DE4437596A1 (en) * 1994-10-20 1996-04-25 Daetwyler Ag Flame-resistant composition for the production of electrical cables with insulation and / or functional integrity
JP3544092B2 (en) * 1997-01-31 2004-07-21 東レ・ダウコーニング・シリコーン株式会社 Liquid silicone rubber composition for high voltage electrical insulation parts and method for producing the same
DE60323974D1 (en) * 2003-08-27 2008-11-20 Borealis Tech Oy Flame-retardant polymer mixture with fine particles
EP1544245A1 (en) * 2003-12-17 2005-06-22 Borealis Technology Oy An environmentally beneficial, flame retardant, halogen free polymer composition and cable

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2010097705A1 *

Also Published As

Publication number Publication date
CA2750512A1 (en) 2010-09-02
AU2010217302A1 (en) 2011-08-11
WO2010097705A1 (en) 2010-09-02

Similar Documents

Publication Publication Date Title
AU2014253577B2 (en) Fire Resistant Compositions
AU2007242059B2 (en) Fire resistant compositions
JP6426727B2 (en) Thermo-vulcanizable polyorganosiloxane composition particularly applicable to the manufacture of electrical wires or cables
US20030199623A1 (en) Insulating composition for a security electric cable
AU2014253576B2 (en) Fire Resistant Materials
WO2010097705A1 (en) A fire performance material, and cable including the material
KR20190055932A (en) Insulation composition having an excellent low-temperature resistance and flexibility and cable comprising an insulation layer formed from the same
CN105367882A (en) Flexible chemical crosslinking low-smoke zero-halogen flame-retardant polyolefin sheathing material and preparation method
AU2012200028B2 (en) A Fire Resistant Cable
CN106504817A (en) A kind of flexible halogen-free flameproof fireproof cable and preparation method thereof
CN117316516A (en) Ceramic high-temperature-resistant cable and preparation method thereof
CN109776934B (en) Polyolefin composite material for fire-resistant cable
EP3524428B1 (en) Multi-layer insulated wire and method of manufacturing the same
EP3832672B1 (en) Flame- retardant electrical cable
CN105575456A (en) Cold-resistant halogen-free flame-retardant copper composite cable material and preparation method thereof
US8642889B2 (en) Wire construction for cables having insulation and functionality applying in case of fire
CN118824623B (en) A high-flexibility and high-flame-retardant mineral special insulation fireproof cable and its preparation method
Ivanov 19, United States i, Patent Application Publication to, Pub. No.: US 2015/0147571 A1
EP4089693B1 (en) Flame-retardant cable
US11810695B2 (en) Cable comprising a fire-resistant ceramic layer
JPH03276514A (en) flame retardant cable
JP2001266649A (en) Polyvinyl chloride composition and electric cable using the same
JP2013028694A (en) Insulator resin composition, electric wire, and cable
JPS62201957A (en) Surfactant-resistant vinyl chloride resin composition
JPH09137019A (en) Vinyl chloride resin composition

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20110926

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20120418