Ceramifiable fiber reinforced tape with thermally conductive layer

Abstract

Composite tapes can include a ceramifiable tape bonded to a thermally conductive layer. The ceramifiable tape can include a plurality of unidirectional glass fibers in a ceramifiable matrix composed of an organic polymer, a silica and an alkaline compound, e.g., a metal carbonate. Advantageously, the ceramifiable tape can form stable structures at elevated temperatures while the thermally conductive layer can facilitate the formation of such structures. Such composite tapes can be used to improve the fire resistance of construction materials and can be used to prepare construction materials such as composite boards.

Description

CERAMIFIABLE FIBER REINFORCED TAPEWITH THERMALLY CONDUCTIVE LAYERCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and all benefit of U.S. Provisional Application No.63 / 751,160, filed January 29, 2025, the entire disclosure of which is fully incorporated herein by reference.TECHNICAL FIELD

[0002] The present disclosure is directed to composite tapes that include a ceramifiable tape adhered to a thermally conductive layer. Advantageously the ceramifiable tape includes a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix and can be ceramified at low temperatures. The thermally conductive layer further can facilitate ceramification and the composite tape advantageously can be used to form flame retardant barrier layers.BACKGROUND

[0003] Continuous fiber reinforced (CFR) thermoplastic tapes and laminates are used in a wide variety of applications due to their high strength to weight ratio and impact resistance. However, when exposed to elevated temperatures, such as those that occur during a fire, all components of CFR tapes naturally do not provide flame barrier properties.

[0004] In addition, regulations are placing increasing demands for higher fire protection requirements in various applications such as building and construction panels, electric vehicle and grid storage battery enclosures, etc. Adding a fire-resistant or retardant coating to materials can improve their performance in a fire, however, such coatings add manufacturing complexity and cost. Often the coating requires a thick layer and increases the overall weight. Hence a continuing need exists to improve the fire resistance of materials particularly improvements that offer light weight and / or lower costs.SUMMARY OF THE DISCLOSURE

[0005] Advantages of the present disclosure include composite tapes that can be used to form flame retardant barriers to protect underlying substrates when exposed to elevated temperatures.

[0006] In certain implementations, a composite tape includes a thermally conductive layer having a first major surface and an opposing second major surface; and a ceramifiable tape, e.g., a first ceramifiable tape, bonded to the first major surface of the thermally conductive layer. The composite tape also can include a second ceramifiable tape bonded to the opposing major surface of the thermally conductive layer. Further additional ceramifiable tapes can be bonded to the first ceramifiable tape and / or the second ceramifiable tape, such as on a second ceramifiable tapebonded to an opposing major surface of the first ceramifiable tape and / or a third ceramifiable tape bonded to an opposing major surface of the second ceramifiable tape. Advantageously, the ceramifiable tape can ceramify at a temperature (a “ceramification temperature”) that is less than a melting temperature of the thermally conductive layer. Moreover, the thermally conductive layer can facilitate ceramification of the ceramifiable tape during exposure to elevated temperatures such as caused by flames, thereby reducing the flame spread rate due to the reduced contribution from the surface in flame propagation.

[0007] In some aspects, the ceramifiable tape includes a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix. The ceramifiable matrix can include an organic polymer and ceramifiable additives. In particular, the ceramifiable matrix can include: (a) an organic polymer; (b) an amorphous silica; and (c) an alkaline compound, e.g., a metal carbonate. The organic polymer can include one or more organic polymers. The organic polymer can be a thermoset polymer, a thermoplastic polymer, or a combination thereof. Exemplary thermoplastic polymers include amorphous polyethylene terephthalate polymers. The ceramifiable matrix can include the organic polymer in the range of about 60 wt% to about 95 wt%, e.g., from 80 wt% to about 95 wt%, based on the total weight of the ceramifiable matrix. The amorphous silica can include fumed silica, silica gel, precipitated silica, or any combination thereof. The silica can be in a range of from about 2 wt% to about 18 wt%, based on the total weight of the ceramifiable matrix. The alkaline compound can include a metal carbonate such as sodium carbonate, calcium carbonate, potassium carbonate, hydrotalcite, or any combination thereof. Further, the ceramifiable tape can include the alkaline compound in a range of from about 0.5 wt% to about 8 wt%, based on the total weight of the ceramifiable matrix. In aspects, the plurality of unidirectional continuous glass fibers can comprise about 30 wt% to about 80 wt%, based on a total weight of the ceramifiable tape. The glass fibers can include a variety of glass fibers such as E-glass, A-glass, C-glass, D-glass, S-glass, ECR-glass, AR glass, R-glass, or any combination thereof.

[0008] In some implementations, the ceramifiable tape can form a self-supporting structure upon exposure to a temperature in a range of from about 350 °C to about 1,000 °C, such as upon exposure to a temperature in a range of from about 350 °C to about 900 °C or from about 350 °C to about 850 °C.

[0009] In other implementations, a composite tape can be prepared by bonding a first ceramifiable tape to a first major surface of a thermally conductive layer. The process can include bonding a second ceramifiable tape to the opposing major surface of the thermally conductive layer. Further, the process can include bonding additional ceramifiable tapes to the firstceramifiable tape and / or the second ceramifiable tape, such as on a second ceramifiable tape bonded to an opposing major surface of the first ceramifiable tape and / or a third ceramifiable tape bonded to an opposing major surface of the second ceramifiable tape. Bonding can include thermally bonding the ceramifiable tapes to the thermally conductive layer and to other ceramifiable tapes.

[0010] Advantageously, composite tapes of the present disclosure are generally flexible and advantageously can be applied to, or used to prepare, construction materials such as a composite board to increase the fire resistance of such construction materials.

[0011] In still further implementations, construction materials, such as a construction board, can include one or more composite tapes adhered thereto. For example, a composite board can include a board having a first major surface and an opposing second major surface and one or more of the composite tapes of the present disclosure adhered to either or both of the first and second major surfaces of the board. The board can comprise a core. Suitable cores for the board may be, for example, a core having a polymeric foam or honeycomb, solid wood, wood chip, or glass fiber reinforced thermoplastic. In some aspects, the core can comprise a thermoplastic polymer.

[0012] Additional advantages of the present disclosure will become readily apparent to those skilled in this art from the following detailed description, wherein only certain embodiments are shown and described, simply by way of illustration of carrying out certain subject matter. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Reference is made to the attached drawings, wherein elements having the same reference numeral designations represent similar elements throughout and wherein:

[0014] FIG. 1 illustrates a composite tape construction including a ceramifiable tape and thermally conductive layer according to an implementation of the present disclosure.

[0015] FIG. 2A illustrates a sectional perspective view of a composite tape according to various implementations of the present disclosure. In particular, FIGS. 2A illustrates a composite tape having a ply of two ceramifiable tapes bonded to each other.

[0016] FIG. 2B illustrates a sectional perspective view of a composite tape according to various implementations of the present disclosure. In particular, FIGS. 2B illustrates a composite tape having a ply of two ceramifiable tapes bonded to each other.

[0017] FIG. 2C illustrates a sectional perspective view of a composite tape according to various implementations of the present disclosure. In particular, FIG. 2C illustrates a composite tape with a first and second ceramifiable tape on each major surface of a thermally conductive layer according to an implementation of the present disclosure.

[0018] FIG. 3 illustrates a sectional perspective view of a composite board including a core and composite tapes adhered to the first and second major surfaces of the board according to an implementation of the present disclosure.

[0019] FIG. 4A and FIG. 4B illustrate pictures of composite tapes after exposing the composite tapes to a flame test.DETAILED DESCRIPTION OF THE DISCLOSURE

[0020] The disclosure may be more fully appreciated by reference to the following description, including the following definitions and examples. Certain features of the disclosed compositions and methods which are described herein in the context of separate aspects, may also be provided in combination in a single aspect. Alternatively, various features of the disclosed compositions and methods that are, for brevity, described in the context of a single aspect, may also be provided separately or in any sub-combination.

[0021] Unless otherwise defined herein, scientific and technical terms used in connection with the present application shall have the meanings that are commonly understood by those of ordinary skill in the art. Further, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular.

[0022] As employed above and throughout the disclosure, the following terms and abbreviations, unless otherwise indicated, shall be understood to have the following meanings.

[0023] As used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise.

[0024] As used in the specification including the appended claims, when a range of values is expressed, such range includes from the one particular value and / or to the other particular value. All ranges are inclusive and combinable. Further, reference to values stated in ranges includes each and every value within that range. The term “about” as used herein when referring to a measurable value such as an amount, a temporal duration, and the like, is meant to encompass reasonable variations of the value.

[0025] The present disclosure is directed to composite tapes comprising one or more ceramifiable tapes in combination with and / or adhered to or bonded to a thermally conductivelayer. The ceramifiable tapes can generally form stable ceramic structures, e.g., a fused glass fiber matrix, upon exposure to elevated temperatures such as those experienced during fire conditions. Further, the ceramifiable tapes can form such structures at a lower range of elevated temperatures, e.g., starting at a temperature as low as 350 °C. In addition, it was discovered that heat transfer from the thermally conductive layer can facilitate ceramification and the rate of ceramification in ceramifiable tapes. It is believed that this effect adds positively to the extent of ceramification even at a distance from the site of elevated temperature exposure. As heat is transferred by the thermally conductive layer, ceramification of the ceramifiable tape occurs faster than the flame is able to propagate on the surface. The combination of these layers reduces the ability of the flame to spread by forming a non-flammable surface that impedes the flame to spread and, therefore, enhances the fire retardancy of the overall system.

[0026] Advantageously, composite tapes of the present disclosure are generally flexible and can be included as one or more layers on various articles or structures to increase the fire resistance of articles, shapes, and / or structures. In one aspect, composite tapes of the present disclosure can be included on building materials, such as on one or more major surfaces of construction board or insulation board.

[0027] The composite tapes of the present disclosure include a ceramifiable tape having a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix. In some aspects, the ceramifiable matrix can be composed of: (a) an organic polymer, e.g., an amorphous polyethylene terephthalate polymer; (b) an amorphous silica; and (c) an alkaline compound, e.g., a metal carbonate.

[0028] In some implementations, the ceramifiable tapes can include a significant amount of unidirectional continuous glass fibers, e.g., at least about 30 wt% based on a total weight of the ceramifiable tape. The unidirectional continuous glass fibers may be referred to as simply “continuous glass fibers,” “continuous fibers,” or “glass fibers” herein. Such ceramifiable tapes can form a fused structure of glass fibers with ceramifiable additives in the ceramifiable matrix when exposed to elevated temperatures, which may result in a structure that resists significant shrinkage. In certain aspects, the tape can include at least 30 wt%, 40 wt%, 45 wt%, 50 wt% and up to and including about 80 wt% glass fibers, based on the total weight of the ceramifiable tape. The amount of glass fibers in the composition can further include ranges from about 30 wt% to about 80 wt%, from about 40 wt% to about 75 wt%, from about 45 wt% to about 70 wt%, from about 50 wt% to about 65 wt%, from about 55 wt% to about 60 wt%, or any combinations of ranges thereof.

[0029] Advantageously, the glass fibers used in the ceramifiable tapes have a relatively high softening point (e.g., greater than or equal to 700 °C), enabling them to resist deformation upon exposure to elevated temperatures. For example, the glass fibers can include one or more of E-glass (softening point approximately 846 °C), A-glass (softening point approximately 705 °C), C-glass (softening point approximately 750 °C), D-glass (softening point approximately 771 °C), S-glass (softening point approximately 1056 °C), ECR-glass (softening point approximately 882 °C), AR glass (softening point approximately 773 °C), R-glass (softening point approximately 952 °C), or any combination thereof.

[0030] In some aspects, the plurality of unidirectional continuous fibers embedded in the ceramifiable matrix can be in a tow, yam, end, pic, or roving. In some aspects, the plurality of unidirectional continuous fibers can include a sizing composition. The sizing composition both protects the fiber during processing as well as promotes chemical or mechanical bonding between the ceramifiable matrix and the continuous fibers. Sizing is typically applied by the fiber manufacturer. For example, the sizing composition can comprise a film former, a lubricant, a coupling agent, or a combination thereof.

[0031] In further aspects, each of the plurality of unidirectional continuous fibers can have an average diameter from about 1 pm to about 40 pm, e.g., from about 13 pm to about 24 pm. In other aspects, a tow, yarn, end, pic, or roving of the plurality of unidirectional continuous fibers can have an average linear mass density from about 100 TEX to about 4400 TEX, e.g., from about 276 TEX to about 4400 TEX. (TEX is a unit of measure in grams per 1,000 meters. Also, the ranges above are a generalization of various fiber filament diameters and TEX.)

[0032] The ceramifiable matrix includes a single or combination of organic polymers, and ceramifiable additives. Optional additional additives can be included in the ceramifiable matrix. The ceramifiable additives, upon heating to a ceramifiable temperature, form a self-supporting structure with the glass fibers. The ceramifiable additives include amorphous silica and an alkaline compound.

[0033] Advantageously, a wide variety of organic polymers can be used to form the ceramifiable matrix of the ceramifiable tape. The organic polymer may be a thermoset or a thermoplastic polymer. As used herein, the term “ceramification temperature” refers to the temperature at which the ceramifiable tape is capable of ceramifiation. In an implementation of the present disclosure, the ceramification temperature of the ceramifiable tape is at least 25 °C above the processing temperature of the organic polymer. The processing temperature is a specific temperature at which the organic polymer needs to be heated to be capable of being molten duringmanufacturing processes such as extrusion. In the case of a thermoplastic polymer, the processing temperature is the specific temperature at which a thermoplastic material needs to be heated to become molten during manufacturing such as extrusion.

[0034] The organic polymer that can be used for such ceramifiable matrices includes reactive organic polymers, e.g., organic polymers having polar groups therein that can more readily decompose into carbonyl or hydroxyl containing compounds upon exposure to elevated temperatures, and generally non-reactive organic polymers, such as a polyolefin, e.g., polyethylene, polypropylene, or any combination thereof. The reactive polymer can include, without limitation, a polyvinyl butyral (PVB), a recycled polyvinyl butyral, a polyamide, a thermoplastic polyurethane, an aliphatic polyketone, polycarbonate, a polyester, a polyethylene terephthalate, a polybutylene terephthalate, a polyvinyl alcohol, a polyvinyl acetate, an ethylenevinyl alcohol copolymer, an ethylene-vinyl acetate copolymer, or any combination thereof. The organic polymer also can include a polyorgano silicone, such as a polydimethyl siloxane.

[0035] In an aspect, the organic polymer includes an amorphous polyethylene terephthalate polymer. Amorphous polyethylene terephthalate polymer may allow the ceramifiable tape to be readily thermally bonded to the thermally conductive layer and to be directly adhered to many building and construction materials including construction boards. The amorphous polyethylene terephthalate polymer also appears to have strong interaction with the ceramifiable additives (the amorphous silica and alkaline compound) and facilitates the ceramification process at elevated temperatures.

[0036] The amount of organic polymer in the ceramifiable matrix can be at least 60 wt%, based on the total weight of the ceramifiable matrix, such as at least 70 wt%, at least 75 wt%, at least 80 wt% and up to and including 95 wt%, such as in a range of from about 80 wt% to about 90 wt% or 95 wt%, based on the total weight of the ceramifiable matrix.

[0037] The ceramifiable matrix of the present disclosure further includes amorphous silica, such as one or more of fumed silica, silica gel, precipitated silica, amorphous silica, or any combination thereof. It is believed that the silica in the composition facilitates fusing of glass fibers in the ceramifiable tape at elevated temperatures. It is believed that free (isolated or geminal) surface silanol groups on the silica and glass fibers can facilitate condensation reactions between the silica and glass fibers. In some aspects, the silica can have a diameter in° a range of from about 3 nm to about 150 nm. For example, precipitated silica and fume silica can have primary structures with an average diameter of about 5-100 nm and agglomerated average diameters of about 1-40 microns. The ceramifiable matrix of the present disclosure can include silica in an amount of atleast 1.5 wt%, such as at least 2 wt%, at least 3 wt%, at least 4 wt%, at least 6 wt%, at least 8 wt%, at least 10 wt%, at least 12 wt%, at least 14 wt%, at least 16 wt%, or at least 18 wt%, including any amounts therebetween, based on the total weight of the ceramifiable matrix. For example, a ceramifiable tape can include silica in a range of from about 1.5 wt% to about 18 wt% and any ranges therebetween or in a range of from about 1.7 wt% or 2 wt% to about 18 wt% and any ranges therebetween, based on the total weight of the ceramifiable matrix.

[0038] Ceramifiable matrices of the present disclosure further include an alkaline compound, preferably Group I metal salts, such as a metal carbonate. It is believed that the alkaline compound in the ceramifiable matrix can activate surfaces of the silica and glass fiber, as well as optional metal silicates that may be included in the matrix, which in turn facilitates silanol condensation reactions and fusing of silica and glass fibers to themselves and to each other. The alkaline compound may also catalyze decomposition of the organic polymer, which may further activate the silica surface by generating more silanol groups.

[0039] In some aspects, the alkaline compound can be one or more of: an alkali metal carbonate, such as sodium or potassium carbonate, calcium carbonate, hydrotalcite, or any combination thereof. The ceramifiable tapes of the present disclosure can include the alkaline compound, e.g., metal carbonate, in an amount of at least 0.5 wt%, such as at least 1 wt%, at least 2 wt%, at least 3 wt%, at least 4 wt%, at least 5 wt%, at least 6 wt%, at least 7 wt% and up to about 8 wt%, including any amounts therebetween, based on the total weight of the ceramifiable matrix. For example, a ceramifiable tape can include the alkaline compound in a range of from about 0.8 wt% to about 6.6 wt%, based on the total weight of the ceramifiable matrix.

[0040] In an implementation of the present disclosure, a molar ratio of silica to alkaline compound is from about 1.5:1 to about 6:1, preferably about 2:1 to about 5:1, and more preferably about 3:1 to about 4.5:1. It is believed the alkaline compound catalyzes silanol condensation reaction. However, higher alkaline content could also weaken the silicate glass network. Therefore, there seems to be a certain silica to alkaline compound ratio for the ceramifiable tapes of the present disclosure that leads to a quick formation of silicate glass network with good thermal and mechanical properties when exposed to elevated temperatures, such as those that occur during a fire.

[0041] The ceramifiable tapes of the present disclosure can further include optional additives, which can improve thermal and / or mechanical characteristic of the composition. For example, the ceramifiable tapes of the present disclosure can include, based on the total weight of the ceramifiable matrix, greater than 0 wt% to about 20 wt% optional additives. For example, theceramifiable matrix can include optional additives in an amount of at least 0.1 wt%, such as at least 0.5 wt%, at least 1 wt%, at least 2 wt%, at least 3 wt%, at least 4 wt%, at least 6 wt%, at least 8 wt%, at least 10 wt%, at least 12 wt%, at least 14 wt%, at least 16 wt%, at least 18 wt%, and any amounts therebetween, based on the total weight of the ceramifiable matrix. For example, the ceramifiable tape can include additional optional additives in a range of from about 0.1 wt% to about 20 wt% and any ranges therebetween. Such additives can be one or more of a metal silicate, e.g., a calcium silicate, magnesium silicate, aluminum silicate, wollastonite, sepiolite, or any combination thereof. Additives such as these metal silicates can improve thermal and mechanical properties of the ceramifiable tape and further the resulting ceramified composition after exposure to elevated temperatures.

[0042] A variety of thermally conductive layers can be bonded to the ceramifiable tape to form the composite tape. The thermally conductive layer can include, for example, a metal, a metal alloy, aluminum, tin, copper, nickel, brass, lead, titanium, carbon fibers, carbon nanotubes, or any combination thereof. The thermally conductive layer can be in the form of a foil. In various aspects, the thermally conductive layer is isotropically thermally conductive, meaning that it transfers heat substantially equally in all directions. In an aspect, the thermally conductive layer can have a thermal conductivity of at least about 30 W / (m K). For example, the thermally conductive layer can have a thermal conductivity of at least 30 W / (m K), at least 35 W / (m K), at least 40 W / (m K), at least 50 W / (m K), at least 60 W / (m K), at least 100 W / (m K). In an aspect, the thermally conductive layer can have a thermal conductivity in the range of about 30 W / (m K) to about 450 W / (m K), e.g., from about 35 W / (m K) to about 415 W / (m K), or from about 40 W / (m K) to about 400 W / (m K), or from about 50 W / (m K) to about 350 W / (m K), or from about 100 W / (m K) to about 300 W / (m K).

[0043] In an implementation, the thermally conductive layer can have a melting temperature that is greater than the ceramification temperature of the ceramifiable tape. The melting temperature may be determined by conventional methods. For example, the melting temperature may be determined by ASTM E794. In implementations, the ceramification temperature of the ceramifiable tape is at least 25 °C less than the melting point of the thermally conductive layer that it is laminated to. That is, the temperature difference between the ceramification temperature of the ceramifiable tape and the melting point of the thermally conducive layer is at least 25 °C. In an aspect, the temperature difference between the ceramification temperature of the ceramifiable tape and the melting point of the thermally conducive layer is at least 50 °C, at least 100 °C, or at least 150 °C. Stated differently, the melting point of the thermally conductive layer, is at least 25°C, such as at least 50 °C, at least 100 °C, or at least 150 °C, more than the ceramification temperature of the ceramifiable tape.

[0044] Advantageously, the ceramifiable tape can be thermally bonded directly to the thermally conductive layer due to the choice of organic polymer, the choice of thermally conductive layer material, or the combination of the choice of organic polymer and the choice of thermally conductive layer material. In some implementations, the ceramifiable tape can be bonded to the thermally conductive layer optionally using an adhesive layer.

[0045] FIG. 1 illustrates a composite tape (100) including a ceramifiable tape (110) bonded to a thermally conductive layer (120). The ceramifiable tape (110) includes a plurality of continuous fibers (102) embedded in a ceramifiable matrix (104). FIG. 1 further illustrates the plurality of continuous glass fibers are oriented in essentially the same direction as one another (Z direction). That is, the plurality of continuous fibers are unidirectional.

[0046] The ceramifiable tape (110) has a first major surface (111) and a second major surface (113). The thermally conductive layer (120) also have a first major surface (121) and a second major surface (123). As shown in FIG. 1, the first major surface (111) of the ceramifiable tape (110) is bonded to the first major surface (121) of the thermally conductive layer (120).

[0047] As further shown with reference to the X, Y, and Z axes, the ceramifiable tape can have a length in the Z direction, a width in the X direction and a thickness in the Y direction. The composite tape length can be greater than or similar to its width, but the thickness is substantially less than either its length or width. For example, the composite tape can have a width in a cross direction (X direction) in a range of about 6 mm to about 3050 mm (about 0.25 inches (in) to about 120 in), such as from 10 mm, 15 mm, 20 mm, 25 mm, 50 mm, 75 mm, 100 mm, 150 mm, 200 mm, or 250 mm to about 3050 mm, 1500 mm, 1400 mm, 1300 mm, 1200 mm, 1000 mm, 900 mm, 500 mm, or 200 mm, or any value or range therebetween. For example, the width may be from 10 mm to 3050 mm, from 10 mm to 1500 mm, from 10 mm to 1400 mm, from 10 mm to 1300 mm, from 10 mm to 1200 mm, from 10 mm to 1000 mm, from 10 mm to 900 mm, from 10 mm to 500 mm, from 10 mm to 200 mm, from 20 mm to 3050 mm, from 20 mm to 1500 mm, from 20 mm to 1400 mm, from 20 mm to 1300 mm, from 20 mm to 1200 mm, from 20 mm to 1000 mm, from 20 mm to 900 mm, from 20 mm to 500 mm, from 20 mm to 200 mm, from 50 mm to 3050 mm, from 50 mm to 1500 mm, from 50 mm to 1400 mm, from 50 mm to 1300 mm, from 50 mm to 1200 mm, from 50 mm to 1000 mm, from 50 mm to 900 mm, from 50 mm to 500 mm, from 50 mm to 200 mm, from 100 mm to 3050 mm, from 100 mm to 1500 mm, from 100 mm to 1400 mm, from 100 mm to 1300 mm, from 100 mm to 1200 mm, from 100 mm to 1000 mm, from 100 mm to 900 mm,from 100 mm to 500 mm, or from 100 mm to 200 mm, including any and all ranges and subranges therein.

[0048] The thickness of the composite tape (100) is the sum of the thicknesses of the ceramifiable tape (110) and the thermally conductive layer (120). For example, the ceramifiable tape can have a thickness (Y direction) in a range from about 0.1 mm to about 1 mm (about 4 mil to about 40 mil), such as from about 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm to about 0.7 mm, 0.8 mm, 0.9 mm, 1 mm or any value or range therebetween. For example, the ceramifiable tape may have a thickness of from about 0.1 mm to about 1 mm, from about 0.2 mm to about 1 mm, from about 0.3 mm to about 1 mm, from about 0.4 mm to about 1 mm, from about 0.5 mm to about 1 mm, from about 0.1 mm to about 0.9 mm, from about 0.2 mm to about 0.9 mm, from about 0.3 mm to about 0.9 mm, from about 0.4 mm to about 0.9 mm, from about 0.5 mm to about 0.9 mm, from about 0.1 mm to about 0.8 mm, from about 0.2 mm to about 0.8 mm, from about 0.3 mm to about 0.8 mm, from about 0.4 mm to about 0.8 mm, from about 0.5 mm to about 0.8 mm, from about 0.1 mm to about 0.7 mm, from about 0.2 mm to about 0.7 mm, from about 0.3 mm to about 0.7 mm, from about 0.4 mm to about 0.7 mm, or from about 0.5 mm to about 0.7 mm, including any and all ranges and subranges therein.

[0049] The thermally conductive layer can have a thickness (Y direction) of at least about 0.5 mil, such as at least about 1 mil (0.025 mm) and can be in a range of from about 0.01 mm to about 1 mm (about 0.4 mil to about 40 mil), such as in a range from about 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.08 mm to about 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 1 mm, or any value or range therebetween. For example, the thermally conductive layer may have a thickness of from about 0.01 mm to about 1 mm, from about 0.02 mm to about 1 mm, from about 0.03 mm to about 1 mm, from about 0.04 mm to about 1 mm, from about 0.05 mm to about 1 mm, from about 0.01 mm to about 0.5 mm, from about 0.02 mm to about 0.5 mm, from about 0.03 mm to about 0.5 mm, from about 0.04 mm to about 0.5 mm, from about 0.05 mm to about 0.5 mm, from about 0.01 mm to about 0.4 mm, from about 0.02 mm to about 0.4 mm, from about 0.03 mm to about 0.4 mm, from about 0.04 mm to about 0.4 mm, from about 0.05 mm to about 0.4 mm, from about 0.01 mm to about 0.3 mm, from about 0.02 mm to about 0.3 mm, from about 0.03 mm to about 0.3 mm, from about 0.04 mm to about 0.3 mm, or from about 0.05 mm to about 0.3 mm, including any and all ranges and subranges therein. In certain aspects, the thickness of the composite tape is the sum of the thickness of the ceramifiable tape and the thermally conductive layer and can range from about 0.1 mm to about 1.5 mm.

[0050] As exemplified in FIG. 1, the plurality of continuous fibers are each generally oriented in a first direction, i.e., the Z direction (longitudinal or length direction) or 0° from the Z axis. As further illustrated, the plurality of continuous fibers (102) span all or substantially all of the width (X direction) of the ceramifiable matrix (104) and ceramifiable tape (110).

[0051] In some implementations, a ceramifiable tape can be stacked on top of another ceramifiable tape forming a multi-ply laminate of layers of ceramifiable tapes on the thermally conductive layer. The multi-ply laminate can be laminated by heating layers of ceramifiable tape at a temperature below the decomposition temperature of the organic polymer in the ceramifiable matrix. It will be appreciated that such a laminate can include additional layers of the ceramifiable tape, e.g., at least 3, 4, 5, 6, 7, 8, etc. layers of ceramifiable tape. For example, a ply or laminate can include four to six layers of ceramifiable tape (e.g., a quad -ply or 6-ply) which can be used to improve the fire resistance of the overall system as well as reinforce the system.

[0052] In addition, the fibers in the various ceramifiable tape layers can be oriented in the same or in different directions relative to other fibers in ceramifiable tape layers. For example, a laminate can include a first ceramifiable tape in which the plurality of continuous fibers are oriented in a first direction and a second ceramifiable tape in which the plurality of continuous fibers are oriented in a second direction, where the second direction is at an angle greater than or equal to 0° and less than or equal to 90° with reference to the first direction, e.g., the angle of the second fibers relative to the first fibers can be at about 0°, 10°, 20°, 30°, 40°, 50°, 60°, 67°, 70°, 80°, 90°, or any value or range therebetween.

[0053] For example, FIG. 2 A and 2B illustrate a laminate of two ceramifiable tapes adhered to one another. In particular, FIGS. 2 A and 2B illustrate a composite tape including a thermal barrier layer (220) having a major surface (221) and a first ceramifiable tape (210a) bound to the major surface of the thermal barrier layer. In this example, the composite tape includes a second ceramifiable tape (210b, 210c) bonded to an opposing major surface (213) of the first ceramifiable tape (210a). The first layer of ceramifiable tape (210a) includes a plurality of continuous fibers (202a) that are oriented in a first direction, i.e., at 0° degrees from the Z direction (or at a 90° angle from the X direction). As shown in FIG. 2 A, the second ceramifiable tape (210b) includes a plurality of continuous fibers (202b) that are also oriented in a first direction, i.e., at 0° degrees from the Z direction (or at 90° degree angle from the X direction). As shown in FIG. 2B, the second ceramifiable tape (210c) includes a plurality of continuous fibers (202c) that are oriented in a second direction, i.e., at 90° degrees from the Z direction (or at 0° degree angle from the X direction). Hence, in FIG. 2B, the plurality of continuous fibers in the second layer are oriented atan angle of about 90° with reference to the first direction (e.g., the second ceramifiable tape is rotated 90° from the Z-axis).

[0054] FIG. 2C illustrates another implementation of a composite tape of the present disclosure. As shown in FIG. 2C, a first ceramifiable tape (21 Of) is bonded to a first major surface (221) of a thermally conductive layer (220). The first ceramifiable tape (210f) can have a first major surface (21 If) and a second major surface (213f) with the first major surface of the ceramifiable tape (21 If) being bonded to the first major surface (221) of the thermally conductive layer (220). In FIG. 2C, the composite tape also includes a second ceramifiable tape (210e) bonded to the second, opposing major surface (223) of the thermally conductive layer (220). The second ceramifiable tape (210e) has a first major surface (21 le) and a second major surface (213e) and the first major surface of the second ceramifiable tape (21 le) is bonded to the second, opposing major surface (223) of the thermally conductive layer (220). While not shown, the composite tape of FIG. 2C can further include one or more additional ceramifiable tapes bonded to either or both of the first or second ceramifiable tapes.

[0055] The composite tapes of the present disclosure can reinforce various structures due to the plurality of continuous glass fibers and can further improve the fire resistance of underlying materials due to the components of the ceramifiable matrix together with the glass fibers. Further, the ceramifiable tapes of the present disclosure can exhibit limited change in shape following exposure to elevated temperatures such as those likely to be encountered in a fire condition. An advantage of the ceramifiable tapes of the present disclosure is that they can resist shrinking after exposure to elevated temperatures. While the organic polymer component of the ceramifiable matrix decomposes, the silica component tends to fuse the glass fibers together to form a fused glass fiber matrix. For example, the ceramifiable tapes of the present disclosure can resist shrinking as determined by measuring a test specimen along a length direction in which the reduction in length is less than 10%, such as less than 5% and even less than 2% after exposing the test specimen to elevated temperatures at 900 °C.

[0056] As indicated above, the ceramifiable tape of the present disclosure can be ceramified at relatively low temperatures. The ceramification temperature of the ceramifiable tape may be the lowest temperature at which the ceramifiable additives form a fused structure with the glass fibers within a single ply of the ceramifiable tape in 120 seconds or less. Ceramifiable tapes of the present disclosure can form self-supporting structures which remain rigid and do not undergo significant heat induced deformation or flow. For example, the ceramifiable tapes of the present disclosure can form self-supporting structures upon heating the ceramifiable tape to a temperature in a rangefrom about 350 °C to about 1,000 °C, such as from about 350 °C to about 900 °C or about 350 °C to about 850 °C. While the ceramifiable tape may have a ceramification temperature that is up to and including 1,000 °C, it should be understood that ceramification may occur at temperatures above 1,000 °C. For example, fires may produce hotter temperatures than 1,000 °C and ceramification is possible under these conditions. Further, such self-supporting structures can be formed in a relatively short period of time upon exposure to the elevated temperatures such as within about 2 minutes (120 seconds). In other aspects, such self-supporting structures can be formed upon exposure to the elevated temperatures on or after 120 seconds.

[0057] Moreover, and unlike certain existing ceramifiable technologies, the ceramifiable tape of the present disclosure can be ceramified at relatively low temperatures which allows use of thermally conductive layers with low melting points such as aluminum (e.g., aluminum melts at 660.3 °C).

[0058] In addition, it was discovered that heat transfer from the thermally conductive layer can facilitate ceramification of ceramifiable tape when the composite tape is exposed to elevated temperatures and can do so at a distance away from the site of the elevated temperature exposure. It is believed that this effect adds positively to ceramification even at a distance from the site of elevated temperature exposure. Further, it is believed the ceramifiable tape forms ceramic structures from the continuous glass fibers during exposure at elevated temperatures and that such structures can also shield the thermally conductive layer. This evident symbiotic relationship between the ceramifiable tape and the thermally conductive material of a composite tape of the present disclosure can impart improved fire retardancy for an underlying substrate such as in building construction structures and materials.

[0059] Advantageously, composite tapes of the present disclosure can be applied to or used to prepare various building materials including construction board. For example, the composite tapes of the present disclosure can be applied to a construction board having a first major surface and an opposing second major surface and one or more layers of composite tapes adhered to either or both of the first and second major surfaces of the board. The construction board can be composed of a cellulose, polymer, cementitious based material, or a combination thereof.

[0060] In some implementations, the composite tapes of the present disclosure can be used to prepare a construction board. The construction boards may be used in in various building and construction applications. For example, the construction boards may be used in interior walls, ceilings, loft boards, insulation boards, roof decking, and floor boards.

[0061] For example, and as illustrated in FIG. 3, a composite board can include a core (340) having a first major surface (341) and an opposing second major surface (343). One or more layers of composite tapes can be adhered to the first and / or the second major surfaces of the core. As illustrated in FIG. 3, a first composite tape (330a) can be adhered to the first major surface (341) of the core (340). While not shown, in some embodiments, an intermediate layer (e.g, a facer, a scrim, or a reinforcement, etc.) may be between the first composite tape (330a) and the first major surface (341) of the core (340). In FIG. 3, a second composite tape (330b) is adhered to the opposing second major surface (343) of the core (340). While not shown, in some embodiments, an intermediate layer (e.g., a facer, a scrim, or a reinforcement, etc.) may be between the second composite tape (330b) and the opposing second major surface (343) of the core (340). Each of the first and second composite tapes include a thermally conductive layer (332, 334, respectively) sandwiched by a first ceramified tape (314, 318, respectively) and a second ceramifiable tape (312, 316, respectively). In this construct, composite tapes (330a, 330b) act as a skin for the composite board. While not shown, the composite board can further include a foil, e.g., metal foil, and / or a composite tape around each of its edges. Additionally, an end cap, for example a metal (e.g., steel) end cap, may be fitted on one or more edges of the composite board,

[0062] In some aspects, the core can have a foam or honeycomb configuration. The core can be composed of a cellulose material, such as balsa wood, or a polymer including a polymer configured as a foam or honeycomb configuration. Polymers that can be used for a core include, for example, a thermoset, such as a polyurethane or a polyisocyanurate. A thermoplastic can also be used for the core, such as a polyethylene terephthalate (PET), such as a fire-retardant polyethylene terephthalate (FR PET), styrene acrylonitrile (SAN), or polyether imide (PEI). The ceramifiable tapes of the present disclosure can be bonded to construction materials including construction panels and composite board by direct thermal bonding. Alternatively, or in addition, the ceramifiable tapes can be adhered to the materials by adhesive thermoplastic film, glue, or any combination thereof.

[0063] In some aspects, the board thickness, including the composite tape(s) thereon, can range from about 1 mm to about 300 mm. In a non-limiting example, the ceramifiable tape can have a thickness of from about 0.5 mm to about 3 mm on the board. In other examples, a composite board with a core can have a core thickness ranging from about 2 mm to about 299 mm, such as from about 5 mm to about 250 mm.EXAMPLES

[0064] The following examples are intended to further illustrate certain aspects of the subject technology and are not limiting in nature. Those skilled in the art will recognize, or be able to ascertain, using no more than routine experimentation, numerous equivalents to the specific substances and procedures described herein.

[0065] Composite Tape

[0066] A ceramifiable masterbatch (MB) was prepared by mixing all raw materials in a 27 mm twin screw extruder (L / D = 60). Amorphous polyethylene terephthalate (aPET) resin was fed at the main feed (barrel 1). The ceramifiable additives were pre-mixed and side-fed after the first mixing zone (barrel 4). The temperature in all zones was set at 220 °C, except the first heating zone was set at 140 °C. The extruder screw rotated at 350 rpm. The extrudate was cooled on the belt and pelletized.

[0067] Samples of unidirectional (UD) glass fiber ceramifiable tape were prepared using a composite tape processing line. E-glass strands were pulled along the machine direction while a polymer melt blend (aPET and ceramifiable MB) was extruded in the orthogonal direction. The polymer melt blend was fed into a crosshead impregnation die where the E-glass strands and polymer melt were consolidated into a single unidirectional ceramifiable tape, whereupon said ceramifiable tape was cooled and wound onto a core. The extrusion temperatures of the polymer blend ranged from 180-250 °C, with overall ceramifiable tape process line speeds of 10-15 ft. / min. The ceramifiable tapes were then thermally bonded to a foil of aluminum. The glass fiber content of the formed ceramifiable tape was 58 wt%, and the ceramifiable matrix content of the formed tape was 42 wt%. The final compositions of ceramifiable matrix and LT) ceramifiable tape are shown in Tables la and lb, respectively.Table laTable lbFinal Composition of UD Ceramifiable Tape

[0068] Composite Board and Testing

[0069] Composite boards were prepared by adhering one or more composite tapes to both major surfaces of boards having a fire-retardant polyethylene terephthalate (FR PET) foam core. All edges of the composite board were covered with an aluminum foil for testing. The composite boards were approximately four-inch thickness and assembled into a fire room for testing.

[0070] The composite boards were assembled to form the three side walls of a fully enclosed room which was subjected to fire in one of the corners and evaluated by an independent consultant according to NFPA 286-2022 (Standard Methods of Fire Tests for Evaluating Contribution of Wall and Ceiling Interior Finish to Room Fire Growth). Table 2 below provides the results of the testing.Table 2&>>>

[0071] As provided in Table 2 above, composite boards including a composite tape composed of a ceramifiable tape and thermally conductive layer do not contribute to the fire growth and can readily improve the fire resistance of an underlying construction board.

[0072] The composite boards were subjected to fire testing inside a Steiner Tunnel setup according to ASTM E84 (Standard Test Method for Surface Burning Characteristics of Building Materials).

[0073] Comparative Composite Board Testing

[0074] Additional composite boards were prepared by adhering composite tapes to one major surface of the boards. The tapes were prepared with 58 wt% glass fiber, based on a total weight of the tape. Some of the tapes included additives in aPET as noted in Table 3 below. Table 3 provides the sample preparation and Table 4 provides the results of the testing.Table 3*Approximate percentage by weight based on total ceramifiable matrix. The additives included ceramifiable additives (silica and sodium carbonate) and calcium silicate additive.Table 4

[0075] As provided in Table 4 above, composite boards including a composite tape composed of a ceramifiable tape and thermally conductive layer can significantly reduce both Flame Spread Index and Smoke Developed Index, thus reducing the flame front advancement and improving the fire resistance to the underlying construction board.

[0076] Composite Tapes with Different Thermal Conductive Layers

[0077] Composite tapes were prepared with either an aluminum thermal conductive layer (about 0.02 inches thick) or steel thermal conductive layer (about 0.02 inches thick). The ceramifiable tapes included glass fibers in an aPET matrix with ceramifiable additives (silica and sodium carbonate). A three-ply laminate of the ceramifiable tape was thermally adhered to the two thermal conductive materials and tested for extent of ceramification on the surface by applying a propane torch to the ceramifiable tape side. Additional details about the tapes and test are provided in Table 5 below.Table 5

[0078] FIG. 4A and 4B illustrate pictures of the tested laminates after exposure to the propane torch. It was observed that ceramification was faster and to a higher degree on the sample with the aluminum layer than the sample with the steel layer. These tests indicate that symbiotic effect between the ceramifiable tape and the thermally conductive material of a composite tape of the present disclosure is amplified with increasing the thermal conductivity of the thermally conductive layer. The composite tapes including the ceramifiable tape and the thermally conductive layer with higher thermal conductivity can enhance fire retardancy for an underlying substrate such as in building construction structures and materials due to the advancement of ceramification front past the source flame front.

[0079] Only certain features and aspects of the present disclosure and examples of their versatility are shown and described in the present disclosure. It is to be understood that the technology disclosed herein is capable of use in various other combinations and environments andis capable of changes or modifications. Thus, for example, those skilled in the art will recognize, or be able to ascertain, using no more than routine experimentation, numerous equivalents to the specific substances, procedures and arrangements described herein. Such equivalents are considered to be within the scope of the invention and are covered by the following claims.

Claims

WHAT IS CLAIMED IS:

1. A composite tape, comprisinga thermally conductive layer having a first major surface and an opposing second major surface; anda ceramifiable tape bonded to the first major surface of the thermally conductive layer; wherein the ceramifiable tape comprises a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix; andwherein the ceramifiable tape has a ceramification temperature that is less than a melting temperature of the thermally conductive layer.

2. The composite tape of claim 1, wherein the ceramification temperature is at least 25 °C less than the melting temperature of the thermally conductive layer.

3. The composite tape of claim 1, wherein the ceramifiable matrix comprises:an organic polymer; andceramifiable additives.

4. The composite tape of claim 3, wherein the ceramifiable matrix comprises:from about 80 wt% to about 95 wt% of the organic polymer, based on the total weight of the ceramifiable matrix;from about 3 wt% to about 20 wt% of the ceramifiable additives, based on the total weight of the ceramifiable matrix; andoptionally one or more additives.

5. The composite tape of any one of claims 3-4, wherein the ceramification temperature is at least 25 °C above the processing temperature of the organic polymer.

6. A composite tape, comprising:a thermally conductive layer having a first major surface and an opposing second major surface; anda ceramifiable tape bonded to the first major surface of the thermally conductive layer; wherein the ceramifiable tape comprises a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix; andwherein the ceramifiable matrix comprises:(a) an organic polymer;(b) an amorphous silica; and(c) an alkaline compound.

7. The composite tape of any one of the preceding claims, wherein the composite tape comprises a second ceramifiable tape bonded to an opposing major surface of the first ceramifiable tape.

8. The composite tape of any one of the preceding claims, wherein the composite tape comprises a second ceramifiable tape bonded to the opposing major surface of the thermally conductive layer.

9. The composite tape of any one of claims 7-8, wherein the plurality of unidirectional continuous glass fibers of the ceramifiable tape are oriented in a first direction and the plurality of unidirectional continuous glass fibers of the second ceramifiable tape are oriented in a second direction, wherein the second direction is at an angle greater than 0° and less than or equal to 90° with reference to the first direction.

10. The composite tape of any one of claims 7-8, wherein the plurality of unidirectional continuous glass fibers of the ceramifiable tape are oriented in a first direction and the plurality of unidirectional continuous glass fibers of the second ceramifiable tape are oriented in a second direction, wherein the second direction is at an angle that is about 90° with reference to the first direction.

11. The composite tape of any one of the preceding claims, wherein the ceramifiable matrix comprises the organic polymer in the range of about 85 wt% to about 95 wt%, based on the total weight of the ceramifiable matrix.

12. The composite tape of any one of the preceding claims, wherein the silica comprises fumed silica, silica gel, precipitated silica, or a combination thereof.

13. The composite tape of any one of the preceding claims, wherein the ceramifiable matrix comprises the silica in the range of about 1.5 wt% to about 18 wt%, based on a total weight of the ceramifiable matrix.

14. The composite tape of any one of the preceding claims, wherein the alkaline compound comprises sodium carbonate, calcium carbonate, potassium carbonate, hydrotalcite, or a combination thereof.

15. The composite tape of any one of the preceding claims, wherein the ceramifiable matrix comprises the alkaline compound in the range of about 0.5 wt% to about 8 wt%.

16. The composite tape of any one of the preceding claims, wherein a molar ratio of the silica to the alkaline compound is about 1.5:1 to about 6:1.

17. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers has a softening point of greater than or equal to 700 °C.

18. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers comprise from about 40 wt% to about 80 wt% of the first ceramifiable tape, based on a total weight of the ceramifiable tape.

19. The composite tape of any one of the preceding claims, each of the plurality of unidirectional continuous glass fibers have an average diameter from 13 pm to 24 pm.

20. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers have an average linear mass density from 276 TEX to 4400 TEX.

21. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers are in a tow, yarn, end, pic, or roving.

22. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers comprise E-glass, A-glass, C-glass, D-glass, S-glass, ECR-glass, AR glass, R-glass, or a combination thereof.

23. The composite tape of any one of the preceding claims, wherein the plurality of unidirectional continuous glass fibers comprise a sizing composition, the sizing composition comprising a film former, a lubricant, a coupling agent, or a combination thereof.

24. The composite tape of any one of the preceding claims, wherein the ceramifiable matrix further comprises, based on the total weight of the ceramifiable matrix, greater than 0 wt% to about20 wt% additives, the additives comprising metal silicates, calcium silicates, magnesium silicates, aluminum silicates, wollastonite, sepiolite, or a combination thereof.

25. The composite tape of any one of the preceding claims, wherein the ceramifiable tape is capable of forming a self-supporting ceramic structure on exposure to a temperature in the range of about 350 °C to about 1000 °C.

26. The composite tape of any of claim 25, wherein the tape is capable of forming the self-supporting ceramic structure on or after 120 seconds.

27. The composite tape of any one of the preceding claims, wherein the thermally conductive layer comprises a metal, a metal alloy, aluminum, tin, copper, nickel, brass, lead, titanium, carbon fibers, carbon nanotubes, or any combination thereof.

28. The composite tape of any one of the preceding claims, wherein the thermally conductive layer has a thickness of at least 0.02 mm.

29. The composite tape of any one of the preceding claims, wherein the thermally conductive layer has a thickness of from about 0.02 mm to about 1 mm.

30. The composite tape of any one of the preceding claims, wherein the thermally conductive layer has a thermal conductivity of at least about 30 W / (m K).

31. The composite tape of any preceding claim, wherein the thermally conductive layer is isotropically thermally conductive.

32. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a thermoplastic polymer, a thermoset polymer, or a combination thereof.

33. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a reactive polymer.

34. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a reactive polymer comprising polyvinyl butyral, recycled polyvinyl butyral, a polyamide, a thermoplastic polyurethane, an aliphatic polyketone, a polycarbonate, a polyester, a polyethylene terephthalate, a polybutylene terephthalate, a polyvinyl alcohol, a polyvinyl acetate,an ethylene-vinyl alcohol copolymer, an ethylene-vinyl acetate copolymer, or any combination thereof.

35. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a non-reactive polymer.

36. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a non-reactive polymer comprising polyolefins, polyethylene, polypropylene, or any combination thereof.

37. The composite tape of any one of the preceding claims, wherein the organic polymer comprises an amorphous polyethylene terephthalate.

38. The composite tape of any one of the preceding claims, wherein the organic polymer comprises a polyorgano silicone.

39. A method of preparing a composite tape comprising:bonding a first ceramifiable tape to a first major surface of a thermally conductive layer; wherein the ceramifiable tape comprises a plurality of unidirectional continuous glass fibers embedded in a ceramifiable matrix; andwherein the first ceramifiable tape has a ceramification temperature that is less than a melting temperature of the thermally conductive layer.

40. A composite board comprising:a board, wherein the board has a first major surface and an opposing second major surface; andone or more of the composite tapes of any one of the preceding claims adhered to the first major surface of the board.

41. The composite board of claim 40, wherein the board comprises one or more of a second composite tapes of any one of the preceding claims adhered to the second major surface of the board.

42. The composite board of any one of the preceding claims, wherein the board comprises a core, wherein the core has a foam or honeycomb configuration.

43. The composite board of claim 42, wherein the core comprises a thermoplastic.

44. A method of preparing a composite board comprising:adhering a composite tape of any one of claims 1-38 to a first major surface of a board.

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