WO1994021452A1 - Materiau en feuille obtenu par voie humide et composites d'un tel materiau - Google Patents

Materiau en feuille obtenu par voie humide et composites d'un tel materiau Download PDF

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Publication number
WO1994021452A1
WO1994021452A1 PCT/US1994/003083 US9403083W WO9421452A1 WO 1994021452 A1 WO1994021452 A1 WO 1994021452A1 US 9403083 W US9403083 W US 9403083W WO 9421452 A1 WO9421452 A1 WO 9421452A1
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WO
WIPO (PCT)
Prior art keywords
wet
sheet material
fibers
laid sheet
graphite particles
Prior art date
Application number
PCT/US1994/003083
Other languages
English (en)
Inventor
Kenneth Wayne Tucker
Gregory Paul Weeks
Original Assignee
E.I. Du Pont De Nemours And Company
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
Application filed by E.I. Du Pont De Nemours And Company filed Critical E.I. Du Pont De Nemours And Company
Priority to KR1019950704074A priority Critical patent/KR960700884A/ko
Priority to JP6521321A priority patent/JPH08508214A/ja
Priority to EP94910986A priority patent/EP0746466A4/fr
Priority to AU63682/94A priority patent/AU686143B2/en
Priority to CA002158922A priority patent/CA2158922C/fr
Publication of WO1994021452A1 publication Critical patent/WO1994021452A1/fr

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63—Inorganic compounds
    • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/16—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by features of a layer formed of particles, e.g. chips, powder or granules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/14—Layered products comprising a layer of synthetic resin next to a particulate layer
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
    • D04H1/413—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties containing granules other than absorbent substances
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
    • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
    • D04H1/732—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by fluid current, e.g. air-lay
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/10—Organic non-cellulose fibres
    • D21H13/20—Organic non-cellulose fibres from macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H13/24—Polyesters
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36—Inorganic fibres or flakes
    • D21H13/38—Inorganic fibres or flakes siliceous
    • D21H13/40—Inorganic fibres or flakes siliceous vitreous, e.g. mineral wool, glass fibres
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/10—Organic non-cellulose fibres
    • D21H13/12—Organic non-cellulose fibres from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H13/14—Polyalkenes, e.g. polystyrene polyethylene
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/10—Organic non-cellulose fibres
    • D21H13/20—Organic non-cellulose fibres from macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H13/26—Polyamides; Polyimides
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36—Inorganic fibres or flakes
    • D21H13/46—Non-siliceous fibres, e.g. from metal oxides
    • D21H13/48—Metal or metallised fibres
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/36—Inorganic fibres or flakes
    • D21H13/46—Non-siliceous fibres, e.g. from metal oxides
    • D21H13/50—Carbon fibres
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Definitions

  • the present invention relates to a wet-laid sheet material that is especially useful in forming compression molded composite plaques, said plaques being thermally and electrically conductive. More specifically, it relates to a wet-laid sheet material prepared from thermoplastic fibers, graphite particles, reinforcing fiber, and microglass fiber, and to composite plaques formed therefrom.
  • conductive fillers such as carbon black, nickel-coated graphite fibers, nickel-coated glass fibers, stainless steel fibers, aluminum coated glass fibers, aluminum fibers, copper powder and flakes, and aluminum powder and flakes
  • conductive fillers can be expensive, difficult to process, subject to corrosion, and can cause resultant polymer system to be non-economical.
  • the system is a wet-laid sheet material made from a thermoplastic fiber, graphite particles for conductivity, reinforcing fibers for obtaining good physical properties, and microglass fiber or a similar fine microfibrous organic or inorganic material, to aid in retention of the graphite particles in the sheet materials.
  • Wet-laid sheet materials are described in U.S. Patent 5,134,016 as fiber reinforced porous sheets.
  • this patent does not disclose sheets, or composite plaques made from them, that are thermally and electrically conductive, that contain graphite particles for conductivity, and that contain microglass fibers to aid in the retention of the graphite particles in the wet-laid sheet material.
  • the wet-laid sheet materials can be stacked and compression molded to form a composite plaque.
  • the resultant plaque is found to have excellent transverse thermal conductivity and electrical conductivity, as shown by the examples herein.
  • Comparable neat thermoplastic polymers on average, have an average volume electrical resistivity of 10 12 -10 15 , with some being even higher, and an average transverse thermal conductivity of about 0.2-0.3 W/mK.
  • the materials of the present invention as illustrated by the examples, have significantly improved conductivity values compared to comparable neat polymers.
  • the wet-laid sheet material of the present invention is useful in forming molded composite parts for use in applications requiring thermally and electrically conductive materials, such as heat sink applications (e., pump housings, power supplies for personal computers, light ballasts, encapsulation of electrical devices and parts thereof (including transformers), etc.), static dissipative or electromagnetic interference/radio frequency interference shielding applications, electrical grounding applications, electrical measuring devices (such as potentiometers), and electromagnetic radiation reflecting applications (e.g., antennae, etc.).
  • heat sink applications e., pump housings, power supplies for personal computers, light ballasts, encapsulation of electrical devices and parts thereof (including transformers), etc.
  • static dissipative or electromagnetic interference/radio frequency interference shielding applications electrical grounding applications
  • electrical measuring devices such as potentiometers
  • electromagnetic radiation reflecting applications e.g., antennae, etc.
  • the wet-laid sheet material is comprised of 30-60 weight percent component (b), 5-15 weight percent component (c), and 0.5-3 weight percent component (d). Most preferably, it is comprised of 35-55 weight percent component (b), 7-15 weight percent component (c), and 0.5-3 weight percent component (c).
  • the weight percent of component (a) is sufficient to bring the total weight of components (a), (b), (c), and (d) to 100 weight percent. The weight percents given above are based upon the total weight of components (a), (b), (c), and (d) only.
  • thermoplastic fibers include, but are not limited to, polyester fibers, polyamide fibers, polypropylene fibers, copolyetherester fibers, polyethylene terephthalate fibers, polybutylene terephthalate fibers, polyetherketoneketone (PEKK) fibers, polyetherether- ketone (PEEK) fibers, liquid crystalline polymer (LCP) fibers, and mixtures thereof.
  • Polyamide fibers include, but are not limited to, nylon 6, 66, 11, 12, 612, and high temperature "nylons" (such as nylon 46).
  • the thermoplastic fibers are generally fine (about 0.5-20 denier), short (about 1-5 cm), staple fibers, possibly containing precompounded conventional additives, such as antioxidant, stabilizers, lubricants, tougheners, etc.
  • the thermoplastic fibers may be surface treated with a dispersing aid.
  • the preferred thermoplastic fibers are polyamide and polyethylene terephthalate fibers, with the most preferred being polyethylene terephthalate fibers.
  • the thermoplastic globules originate from the thermoplastic fibers when they are melted during manufacture of the wet-laid sheet material, which is described below.
  • the component (b) graphite particles can be natural or synthetic graphite particles, but in either case, generally are -35 Tyler mesh in particle size.
  • the graphite particle size is -35 Tyler mesh, with at least 85% of the particles being greater than 400 Tyler mesh.
  • the most preferred graphite particles have a -35/ + 100 Tyler mesh size range.
  • Tyler mesh values can be correlated to particle size by those skilled in the art. Specific terminology to describe graphite particles useful herein include graphite powder, graphite/coke mixtures, scrap graphite, natural graphite, natural/synthetic graphite mixtures, graphite fines, and graphitized petroleum coke.
  • the preferred graphite particles are graphitized premium petroleum coke particles (graphitized at greater than 2500°C, preferably 2700-3400°C, most preferably 2700-3100°C) and electrode-grade scrap graphite.
  • the preferred graphite particles are premium petroleum coke particles graphitized at about 2700-3200°C, most preferably 2800-3100°C.
  • the component (c) reinforcing fibers include, but are not limited to, glass fibers, carbon fibers, metal fibers, polyaramid fibers (such as Kevlar®), and metal whiskers, with carbon fibers and glass fibers being preferred.
  • the most preferred reinforcing fibers are long E glass fibers, having an average length of 0.25-1.5 inches, preferably about 0.5-1 inch, which are commercially available.
  • the diameter of the E glass fibers is generally 10-20 microns, preferably 12-16 microns.
  • the reinforcing fibers are generally used for imparting good tensile strength to the wet-laid sheet material.
  • the component (d) microglass fibers are used primarily to aid in retention of the graphite particles in the sheet material.
  • the microglass fibers are usually in the form of a filter-type sheet material. When the wet-laid sheet material is prepared, the filter-type sheet material is broken up during mixing to yield the microglass fibers.
  • the microglass fiber in the wet-laid sheet material is generally shorter and thinner than the glass reinforcing fibers.
  • the length of the microglass fibers generally ranges from 20 microns to 0.25 inches and the width generally ranges from 0.3-6, preferably 0.3-4, microns.
  • the majority of the microglass fibers have a diameter of 0.3-1.0 microns and an aspect ratio of 100/1 or greater.
  • microglass fiber In addition to mircroglass fiber, it is anticipated that other fine inorganic or organic microfiber materials of similar diameter and length may be substituted in whole or in part for component (d), provided said other microfiber materials accomplish the same function of enhancing the capture of component (b) as do the microglass fibers.
  • the wet-laid sheet material of the present invention can be made by techniques readily available to those skilled in the art, such as a traditional paper-making process or as described in U.S. Patent 5,134,016 or European Patent Publication No.341977.
  • a preferred method of making the wet-laid sheet material at least components (a), (b), (c), and (d) are mixed with water to form an aqueous suspension.
  • the aqueous suspension can be blended in a pulper to ensure uniformity.
  • the aqueous suspension is then applied to a porous substrate (usually an endless belt or screen) to form a porous sheet material, or web.
  • An example of an acceptable screen is Duotex 116 mesh screen.
  • the porous substrate should have holes that are not so big that a substantial amount of graphite particles in the wet-laid sheet material would pass through them.
  • the porous sheet material is then dried, for example in a rotary through air or forced air bonder dryer, and heated at a temperature high enough to cause the water to evaporate and the thermoplastic fiber to melt (but low enough to prevent degradation), thereby resulting in adherence of the thermoplastic fiber to the reinforcing fiber and graphite particles in the wet-laid sheet material.
  • thermoplastic fiber may resemble "globules" after melting of the thermoplastic fibers.
  • Globules are defined in U.S. Patent 5,134,016, incorporated hereby by reference.
  • the globules formed are not necessarily spherical in shape as the term may imply, but rather they are really lumps of previously molten thermoplastic fiber.
  • a composite sheet or plaque can be prepared via compression molding techniques, such as those described in U.S. Patent 5,134,016 (especially column 4), already incorporated herein by reference. In doing so, several individual wet-laid sheet materials are stacked together to produce a thickness suitable for molding. Optionally, the sheet materials can be mechanically sewn together for easier processing.
  • the stack of sheet materials are placed in a mold having a desired design. Predrying may be required, starting at room temperature and using slow cycle molding. When condensation polymers, such as polyethylene terephthalate, are used as the thermoplastic fiber component, it is recommended that the stack of sheet materials be dried to less than a 0.02% moisture level prior to molding.
  • the mold containing the stack of sheet materials is placed in a heated platen press, where temperature is raised and pressure is increased to amounts sufficient for the thermoplastic fiber to have some melt flow. Then, the mold and its contents are cooled under pressure. The resulting composite plaque is then removed and evaluated for future use.
  • PET fiber was a polyethylene terephthalate fiber (sold commercially by E. I. du Pont de Nemours and Company as Dacron®) containing 0.35 %-l% antioxidant. The fibers, on average, had a length of about 1/4 inch and a diameter of about 13 microns. Except for Examples 12 and 13, "Graphite” was graphitized (at 3000°C) premium petroleum coke particles. The size of the particles is given in the Tables below, based upon Tyler mesh sieve analysis. The graphite used in Examples 12 and 13 is described in Table 1 A below. In Examples 16-25, the graphite was from the same lot of material.
  • E-glass was E glass fiber (K diameter: 12.7 to 13.9 microns) that was commercially available from Owens Corning Fiberglass as 133A-AB. It was used in the form of chopped strands and it had a polyurethane sizing on the fiber surface. The average E-glass length is provided in the Tables below.
  • Carbon fiber was carbon fiber as described in U.S. Patent 4,861,653.
  • Microglass was binderless high efficiency filter medium microglass fiber commercially available from Hollingsworth and Vose Company as HB-5341. It was used in the form of 18-inch wide sheets, which, upon agitation, broke up into individual fibers. The diameter of the individual fibers varied from 0.3 to 4 microns and the length of the individual fibers varied from 20 microns to over 1 inch.
  • the wet-laid materials were generally made by the same process. Fifty pounds of each formulation were dispersed in 1000 gallons of water to create a slurry. Specifically, PET fiber was added first to the water and mixed for about 10 minutes. Reinforcing fiber was added next and mixed for about 2-3 minutes. Microglass filter medium, in paper form, was torn into small pieces and added to the slurry. Finally, graphitized coke was added to the slurry. The slurry, having first been diluted with 900 gallons/minute of recirculating water in the usual manner, was fed at a rate of 100 gallons per minute to the forming box of an inclining wire paper machine equipped with Duotex synthetic 116 mesh wire. Collected sheet material was dried and heated at 277°C for about 30 seconds to evaporate water and melt the thermoplastic fiber. The wet-laid dried and heated sheet material was then rolled for storage purposes.
  • the rolled wet-laid sheet material was unrolled and cut into 10.5 -inch by 10.5-inch sheets to be pressed into higher density composite plaques having fewer loose fibers.
  • Approximately 1 lb. of the 10.5-inch by 10.5-inch dried wet-laid sheet material (to make a plaque approximately 1/8 inch thick) was further dried for 16 hours in a vacuum oven at 4-inch Hg absolute pressure and 105°C under a nitrogen purge. This further dried material ( ⁇ 0.02% water) was then stacked in a 10.5-inch by 10.5-inch mold. A vacuum was applied to the mold to remove any vapors (such as water).
  • the assembly was placed in a 50 ton hydraulic press and pressed at 907 psi and 277°C (mold temperature) for 10 minutes. After the expiration of said 10 minutes, the platen heaters were turned off and allowed to cool. The pressure of 907 psi was maintained until the mold temperature reached 200°C. Then the pressure was allowed to decrease as the temperature of the mold decreased further. When the mold temperature reached 30°C, the platens were opened and the assembly was removed from the press. The composite plaque was then removed from the mold.
  • Transverse thermal conductivity was determined as follows: test specimen were cut from the composite plaques prepared above. The test specimen had a diameter of 2 inches and a thickness of 1/8 inch. These test specimen were tested using a Dynatech (Holometrix) TCHM-DV C-Matic to measure the transverse thermal conductivity through-the-thickness of the specimen. The guarded heat flow meter method (ASTM Standard F433) was used and all measurements were conducted nominally at 50°C.
  • volume electrical resistivity was determined as follows: test specimen (2mm wide by 2mm thick by 25.4mm long) were cut from the composite plaques described above. In the test method, a constant current was sent across the test specimen. The voltage drop was measured across the center 6mm of the test specimen. One measurement was taken for each specimen. All specimen were tested at ambient conditions. Decreasing volume electrical resistivity values indicate increasing electrical conductivity.
  • Tensile properties were determined as follows: test specimen (6.5 inches long, 0.75 inches wide) were cut from the composite plaques described above. These specimen were routed into a "dog-bone" shape so that the gauge length was 2.0 inches and the gauge width was 0.5 inches. The specimen were placed in a screw action mechanical grip.
  • compositions of the wet-laid sheet materials used to make the composite plaques for the examples, along with the test results thereto, are given in the Table 1A andJB below.
  • transverse thermal conductivity is reported as “Ave TC (W/mK) (Trans.)” and volume electrical resistivity is reported as “Ave Vol ER (ohm-cm)”.
  • In-plane (longitudinal) conductivity was determined using a four probe technique ( Figure 1).
  • Test samples having dimensions 32mm x 5mm x 3mm (I x x thickness) were cut from the composite plaque above.
  • test samples were molded into parts having dimensions 32mm x 5mm x 3mm (l x wx thickness).
  • sample heater (3) was glued in good thermal contact by means of a silver paint.
  • the sample was pressed to a heat sink (1) by means of a screw (2). When the sample heater is energized, the generated heat flows through the sample from the sample heater to the sink.
  • the temperature sensor reading ( ⁇ T cg ) was a chromel- constantan-chromel thermocouple. One of the junctions was soldered on the sample heater, while the other was thermally anchored on a copper guard (5) facing the sample heater. The extremities of this thermocouple were also thermally anchored to the sink.
  • the heaters were made of hollow copper blocks in which small electrical resistors were inserted and glued.
  • the power generated in the heater was evaluated by multiplying the current (I) flowing through the resistor by the voltage drop (V) across the resistor.
  • the thermal conductivity is then given by:
  • d is the distance between the two junctions of the thermocouples on the sample (in this case, 8mm) and S is the cross-section of the sample. All voltages were measured by means of a Keithley 195A voltmeter and currents with a Keithley 177 ammeter. The system was completely monitored by computer.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Wood Science & Technology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Reinforced Plastic Materials (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Cleaning Implements For Floors, Carpets, Furniture, Walls, And The Like (AREA)
  • Laminated Bodies (AREA)
  • Conductive Materials (AREA)
  • Paper (AREA)

Abstract

L'invention se rapporte à un matériau en feuille obtenu par voie humide, préparé à partir de fibres thermoplastiques, de particules de graphite, de fibres de renforcement et de microfibres de verre. Ce matériau en feuille est utile pour fabriquer des plaques composites moulées par compression, lesquelles sont thermoconductrices et électroconductrices.
PCT/US1994/003083 1993-03-24 1994-03-22 Materiau en feuille obtenu par voie humide et composites d'un tel materiau WO1994021452A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
KR1019950704074A KR960700884A (ko) 1993-03-24 1994-03-22 습식 적층 시트 재료 및 그들의 복합체(Wet-Laid Sheet Material and Composites Thereof)
JP6521321A JPH08508214A (ja) 1993-03-24 1994-03-22 湿式堆積シート材およびその複合物
EP94910986A EP0746466A4 (fr) 1993-03-24 1994-03-22 Materiau en feuille obtenu par voie humide et composites d'un tel materiau
AU63682/94A AU686143B2 (en) 1993-03-24 1994-03-22 Wet-laid sheet material and composites thereof
CA002158922A CA2158922C (fr) 1993-03-24 1994-03-22 Produit en feuilles applique a l'etat humide, et composites a base de celui-ci

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US3659693A 1993-03-24 1993-03-24
US08/036,596 1993-03-24
US5914893A 1993-05-07 1993-05-07
US08/059,148 1993-05-07

Publications (1)

Publication Number Publication Date
WO1994021452A1 true WO1994021452A1 (fr) 1994-09-29

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PCT/US1994/003083 WO1994021452A1 (fr) 1993-03-24 1994-03-22 Materiau en feuille obtenu par voie humide et composites d'un tel materiau

Country Status (7)

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EP (1) EP0746466A4 (fr)
JP (1) JPH08508214A (fr)
KR (1) KR960700884A (fr)
AU (1) AU686143B2 (fr)
CA (1) CA2158922C (fr)
SG (1) SG49833A1 (fr)
WO (1) WO1994021452A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997015630A1 (fr) * 1995-10-23 1997-05-01 Hoechst Celanese Corporation Cires et polymeres a haute conductivite thermique
WO1997026397A2 (fr) * 1996-01-19 1997-07-24 Vetrotex France S.A. Procede et dispositif de fabrication d'un materiau composite
US7563501B2 (en) 2003-09-25 2009-07-21 General Dynamics Land Systems Integral pigments in composite surfaces
WO2019003115A1 (fr) * 2017-06-29 2019-01-03 3M Innovative Properties Company Article non tissé et son procédé de fabrication
US11493673B2 (en) 2017-06-29 2022-11-08 3M Innovative Properties Company Article and methods of making the same

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100337357C (zh) * 2003-05-08 2007-09-12 大日本油墨化学工业株式会社 燃料电池双极板的生产方法、燃料电池双极板和燃料电池
FR2864094B1 (fr) * 2003-12-19 2006-02-10 Rhodia Industrial Yarns Ag Materiaux composites comprenant un materiau de renfort et une matrice thermoplastique, article compose precurseur de ces materiaux et produits obtenus a partir de ces materiaux
KR101963243B1 (ko) * 2014-09-26 2019-03-29 (주)엘지하우시스 섬유강화 복합재 및 그의 제조방법
FR3049491B1 (fr) * 2016-04-05 2018-09-07 Arkema France Procede de fabrication de pieces en materiau composite avec renforts
JP6724757B2 (ja) * 2016-12-08 2020-07-15 王子ホールディングス株式会社 ガラス繊維不織布、複合体、繊維強化熱可塑性樹脂シート、金属張積層シート、ガラス繊維不織布の製造方法および繊維強化熱可塑性樹脂シートの製造方法

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WO1997015630A1 (fr) * 1995-10-23 1997-05-01 Hoechst Celanese Corporation Cires et polymeres a haute conductivite thermique
WO1997026397A2 (fr) * 1996-01-19 1997-07-24 Vetrotex France S.A. Procede et dispositif de fabrication d'un materiau composite
FR2743822A1 (fr) * 1996-01-19 1997-07-25 Vetrotex France Sa Procede et dispositif de fabrication d'un materiau composite
WO1997026397A3 (fr) * 1996-01-19 1997-10-02 Vetrotex France Sa Procede et dispositif de fabrication d'un materiau composite
US7005024B2 (en) 1996-01-19 2006-02-28 Saint-Gobain Vetrotex France S.A. Process and device for the manufacture of a composite material
US7563501B2 (en) 2003-09-25 2009-07-21 General Dynamics Land Systems Integral pigments in composite surfaces
WO2019003115A1 (fr) * 2017-06-29 2019-01-03 3M Innovative Properties Company Article non tissé et son procédé de fabrication
US11493673B2 (en) 2017-06-29 2022-11-08 3M Innovative Properties Company Article and methods of making the same

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EP0746466A4 (fr) 1998-12-16
JPH08508214A (ja) 1996-09-03
CA2158922C (fr) 2004-09-21
EP0746466A1 (fr) 1996-12-11
KR960700884A (ko) 1996-02-24
AU6368294A (en) 1994-10-11
AU686143B2 (en) 1998-02-05
CA2158922A1 (fr) 1994-09-29
SG49833A1 (en) 1998-06-15

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