Ceramifiable composition and making and using same

Abstract

Ceramifiable compositions can be configured to form stable structures at elevated temperatures. Such ceramifiable compositions include an organic polymer combined with glass fibers, a silica and an alkaline compound such as metal carbonate.

Description

CERAMIFIABLE COMPOSITION AND MAKING AND USING SAMECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and all benefit of U.S. Provisional Patent Application No. 63 / 678,037, filed on July 31, 2024, the entire disclosure of which is fully incorporated herein by reference.TECHNICAL FIELD

[0002] The present disclosure is directed to ceramifiable compositions configured to form stable structures at elevated temperatures. The ceramifiable compositions of the present disclosure include an organic polymer combined with glass fibers, a silica and an alkaline compound such as a metal carbonate.BACKGROUND

[0003] Each year fire accidents cause loss of life and property. Fire safety is a major concern worldwide and results in increasing fire safety performance globally for appliances, wire & cable, building construction products, etc. Additionally, some regulations require materials maintain their structural integrity for a minimum period of time or minimum temperature during a fire event.

[0004] Further, newer technologies are placing ever increasing demands on fire safety such as electric vehicle (EV) battery and grid storage battery technologies. For example, thermal runaway of lithium ion batteries can generate temperatures of greater than 1,000 °C and high pressures due to gas build-up in enclosures and containers housing such batteries. However, traditional flame-retarding polymer composites can easily turn into brittle char layers or ashes without any self-supporting ability, especially after experiencing a full-fledged fire. Hence a continuing need exists for fire resistant materials.SUMMARY OF THE DISCLOSURE

[0005] Advantages of the present disclosure include ceramifiable compositions that can be ceramified at relatively low temperatures, e.g., at 350 °C or at or above the decomposition temperature of an organic polymer included in the composition, whichever is higher. The ceramified composition can also be formed at shorted time periods, e.g., within about 5minutes. Advantageously, the ceramifiable compositions can be formed into ceramic structures, such as a fused glass fiber matrix, that resists shrinking.

[0006] In certain implementations, a ceramifiable composition is provided which includes: (a) an organic polymer; (b) a silica; (c) an alkaline compound, such as a metal carbonate; and (d) from about 30 wt% to about 80 wt% of a glass fiber, based on a total weight of the ceramifiable composition.

[0007] The organic polymer can include reactive organic polymers and non-reactive organic polymers and can be in a range of from about 20 wt% to about 60 wt% based on the total weight of the ceramifiable composition. The silica can include fumed silica, silica gel, precipitated silica, amorphous silica, or any combination thereof. The silica can be in a range of from about 2 wt% to about 15 wt% based on the total weight of the ceramifiable composition. The alkaline compound can include a metal carbonate such as sodium carbonate, calcium carbonate, potassium carbonate, hydrotalcite, or any combination thereof. Further, the ceramifiable composition can include the alkaline compound in a range of from about 0.5 wt% to about 10 wt% based on the total weight of the ceramifiable composition.

[0008] 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. The glass fibers can have an average length of at least 2 mm, such as at least 3 mm, 6 mm, 12 mm, and up to about 25 mm and any values therein, such as an average length in a range of from about 0.4 cm to about 1.2 cm.

[0009] The ceramifiable compositions of the present disclosure can be prepared by combining (a) an organic polymer; (b) a amorphous silica; (c) an alkaline compound such as a metal carbonate; and (d) from about 30 wt% to about 80 wt% of a glass fiber, based on a total weight of the ceramifiable composition.

[0010] In some aspects, the composition is configured to 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, from about 350 °C to about 850 °C. Such self-supporting structure when aged at 350° C for about 10 minutes can have a flexural strength of greater than or equal to 75 psi.

[0011] In other implementations, a ceramified composition can be prepared by providing a ceramifiable composition and heating the ceramifiable composition to a temperature of from about 350 °C to about 1000 °C to form a self-supporting structure.

[0012] Advantageously, ceramified compositions of the present disclosure are generally flexible and advantageously can be molded into various articles, shapes and / or included as oneor more layers on various articles, structures, etc. to increase the fire resistance of articles, shapes and / or structures.

[0013] 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 DRAWING

[0014] The Figure is a plot of flexural strength versus a molar ratio of silica to alkaline compound in ceramifiable compositions after exposing the compositions to different elevated temperatures.DETAILED DESCRIPTION OF THE DISCLOSURE

[0015] 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.

[0016] 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.

[0017] As employed above and throughout the disclosure, the following terms and abbreviations, unless otherwise indicated, shall be understood to have the following meanings.

[0018] 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.

[0019] 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 rangesincludes 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.

[0020] The present disclosure is directed to ceramifiable compositions (which can also be referred to as a ceramizable compositions) that can generally form stable ceramic structures, e.g., ceramified structures, upon exposure to elevated temperatures such as those experienced during fire conditions. Advantageously, the ceramifiable compositions of the present disclosure can be ceramified into self-supporting structures, i.e., the ceramified self-supporting structures remain rigid and do not undergo significant heat induced deformation or flow. They also undergo little if any shrinkage following elevated temperature exposure. The ceramifiable compositions further can form ceramified compositions relatively quickly and at a lower range of elevated temperatures, e.g., starting at temperatures that decomposes an organic polymer component such as a temperature as low as 350 °C.

[0021] As used herein a ceramifiable composition is an organic polymer, an amorphous silica, an alkaline compound and glass fiber composition that is configured to convert to a ceramic structure, i.e., a fused silicate glass fiber matrix, at elevated temperatures, e.g., at temperatures that decompose the organic polymer such as a temperature as low as 350 °C and up to and including about 1,000 °C. The amorphous silica appears to fuse together and with the glass fibers, and the alkaline compound appears to facilitate fusing the glass fibers and silica. Additional optional ingredients can also be included in the ceramifiable composition.

[0022] The ceramifiable compositions disclosed herein may advantageously convert to a ceramic structure at a temperature as low as 350 °C. While the composition is ceramifiable at temperatures 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. Advantageously, ceramifiable compositions of the present disclosure are generally flexible and advantageously can be molded into various articles, shapes and / or included as one or more layers on various articles, structures, etc. to increase the fire resistance of articles, shapes and / or structures. In one aspect, ceramifiable compositions of the present disclosure can form, or be included on, a battery container or battery enclosure, fire resistance panels, wire & cable insulations, etc.

[0023] The ceramifiable compositions of the present disclosure include: (a) an organic polymer; (b) an amorphous silica; (c) an alkaline compound such as a metal carbonate; and (d) glass fibers. The ceramifiable compositions of the present disclosure include a significant amount of glass fibers, e.g., at least about 30 wt% based on a total weight of the ceramifiablecomposition. By including such a significant content of glass fibers, the ceramifiable composition can form fused glass matrix when exposed to elevated temperatures which results in a structure that resists significant shrinkage. In certain aspects, the composition can include at least 30 wt%, 35 wt%, 40 wt% and up to and including about 65 wt%, 70 wt%, 80 wt% glass fibers based on the total weight of the ceramifiable composition. The amount of glass fibers in the composition can further include ranges from about 30 wt% to about 80 wt% and any ranges therein.

[0024] Advantageously, the glass fibers used in the composition have a relatively high softening point (e.g., greater than or equal to 700 °C) to resist deformation upon exposure to elevated temperatures. For example the glass fibers can include one or more of E-glass (softening point of approximately 846 °C), A-glass (softening point of approximately 705 °C), C-glass (softening point of approximately 750 °C), D-glass (softening point of approximately 771 °C), S-glass (softening point of approximately 1056 °C), ECR-glass (softening point of approximately 882 °C), AR glass (softening point of approximately 773 °C), R-glass (softening point of approximately 952 °C), or any combination thereof.

[0025] In some implementations, the glass fibers used in the composition should have sufficient length to form a fused matrix upon exposure to elevated temperatures. For example, the glass fibers can have an average length of at least 2 mm, such as at least 3 mm, 6 mm, 12 mm and up to about 25 mm and any values therein. In some aspects, the glass fibers can have a length ranging from about 5 mm to about 2 cm, such as from about 0.4 cm to about 1.2 cm. In some aspects, the glass fibers can have a wide distribution of lengths. In some aspects, the glass fibers can include two or more fibers of any of the average lengths previously described. Due to fiber attrition in blending operations, fiber length and average fiber length may be determined from the fiber starting length prior to any mixing or blending steps.

[0026] Further, in some aspects the ceramifiable composition of the present disclosure can include glass fiber reinforced long fiber thermoplastic. Such glass fiber reinforced long fiber thermoplastic can be prepared as continuous filaments of fiber, which are melt-impregnated with thermoplastic polymer in a pultrusion process that creates a high performance bond. These unidirectional fiber-reinforced strands are then cut into, for example, 1 / 2 inch (12 mm) composite pellets for convenient processing into net shapes via injection molding. Higher aspect ratio fiber reinforcement through the full length of the pellets results in more robust properties than short / chopped glass fiber filled compounds. An average length of glass fiber in glass fiber reinforced long fiber thermoplastic that can be used in the compositions of thepresent disclosure includes a range of 2 mm to 25 mm. In some aspects, the glass fibers can include a blend of long and short fibers or have a wide distribution of lengths.

[0027] Advantageously, a wide variety of organic polymers can be used to form the ceramifiable compositions of the present disclosure. The organic polymer that can be used for such compositions include 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., a polyethylene, polypropylene, or any combination thereof. The reactive polymer includes, 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, polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherketone (PEK), polyphenylene sulfide, a polyvinyl alcohol, a polyvinyl acetate, an ethylene-vinyl alcohol copolymer, an ethyl ene-vinyl acetate copolymer, or any combination thereof. The amount of the organic polymer in the composition can be at least 20 wt%, based on the total weight of the ceramifiable composition, such as at least 25 wt%, 30 wt%, 35 wt% and up to and including 60 wt% such as in a range of from about 20 wt% to about 60 wt%, based on the total weight of the ceramifiable composition.

[0028] Ceramifiable compositions of the present disclosure further include a 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 composition at elevated temperatures. In some aspects, the silica has a surface and free silanol groups located on the surface. It is known that free (isolated or geminal) silanol group has stretching band at -940 cm’1in FTIR. Such free surface silanol groups can facilitate condensation reactions among 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 fumed silica can have primary structures with an average diameter of about 5 nm to 100 nm and agglomerated average diameters of about 1 pm to 40 pm. The ceramifiable compositions of the present disclosure can include silica in an amount of at least 2 wt%, such as at least 4 wt%, 6 wt%, 8 wt%, 10 wt%, and any amounts therebetween, based on the total weight of the ceramifiable composition. For example, a ceramifiable composition can include silica in a range of from about 2 wt% to about 10 wt% and any ranges therebetween.

[0029] Ceramifiable compositions of the present disclosure further include an alkaline compound such as a metal carbonate. It is believed that the alkaline compound, e.g., metalcarbonate, in the composition can activate surfaces of the silica and glass fiber, as well as optional metal silicates that may be included in the ceramifiable composition, which in turn facilitate silanol condensation reactions and fusing of silica and glass fibers to themselves and to each other. The alkaline compound may also catalyze decomposition of certain organic polymers, which may further activate the silica surface by generating more silanol groups.

[0030] In some aspects, the alkaline compound can be one or more of an alkali metal carbonate, such as sodium carbonate, potassium carbonate, calcium carbonate, hydrotalcite, or any combination thereof. The ceramifiable compositions of the present disclosure can include the alkaline compound in an amount of at least 0.5 wt%, such as at least 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt% and up to about 10 wt% any amounts therebetween, based on the total weight of the ceramifiable composition. For example, a ceramifiable composition can include the alkaline compound in a range of from about 0.5 wt% to about 10 wt% based on the total weight of the ceramifiable composition.

[0031] 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: 1. It is believed that the alkaline compound can catalyze 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 in the ceramifiable compositions 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.

[0032] The ceramifiable compositions of the present disclosure can further include optional additives, which can improve thermal and / or mechanical characteristic of the ceramifiable composition, the ceramified structure formed after exposure to elevated temperatures, or both the ceramifiable composition and the ceramified structure. For example, the ceramifiable compositions of the present disclosure can include, based on the total weight of the composition, greater than 0 wt% to about 20 wt% additives, about 0.5 wt% to about 15 wt% additives, or 2% to about 12 wt% additives. Such additives can be one or more of a metal silicate (e.g., a calcium silicate, magnesium silicate, aluminum silicate, wollastonite, and sepiolite), antioxidants, flame retardants, thermally conductive additives, electrically conductive additives and combinations thereof. Exemplary metal silicates include calcium silicate, magnesium silicate, aluminum silicate, wollastonite, sepiolite, or any combination thereof. For example, the ceramifiable compositions of the present disclosure can include, based on the total weight of the composition, greater than 0 wt% to about 20 wt% metalsilicates, about 0.5 wt% to about 15 wt% metal silicates, 1% to about 12 wt% metal silicates, 2% to about 10 wt% metal silicates, 3% to about 8 wt% metal silicates, or 4% to about 6 wt% metal silicates. Additives such as the above metal silicates can improve thermal and mechanical properties of the resulting ceramified composition after exposure to elevated temperatures.

[0033] Use of an organic polymer in the ceramifiable compositions of the present disclosure advantageously allows ready manufacture of the compositions. For example, the ceramifiable composition of the present disclosure can be prepared by combining: (a) the organic polymer; (b) the silica; (c) the alkaline compound (e.g., metal carbonate); and (d) the glass fibers (e.g., from about 30 wt% to about 80 wt% of a glass fiber, based on a total weight of the ceramifiable composition). Such a combination can be carried out by mixing the ingredients sequentially or components together in a mixer such as in an extruder to form the composition in various forms such as in sheets, layers, pellets, etc. that can be applied to articles and structures, or as a molded article.

[0034] The ceramifiable compositions of the present disclosure find use in many applications that desire a material to impart fire-resistance. Advantageously, the ceramifiable compositions 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 compositions of the present disclosure is that they can resist shrinking after exposure to elevated temperatures. While the organic polymer component of the composition decomposes, the glass fibers and silica components tend to fuse together to form a ceramified composition including a fused silicate glass fiber matrix. For example, the ceramifiable compositions of the present disclosure can resist shrinking as determined by measuring the dimension changes of a test specimen in which the reduction is less than 10%, such as less than 5% and even less than 1% after exposing the test specimen to elevated temperatures at 350 °C or at or above the decomposition temperature of the organic polymer (e.g., at or above 450 °C such as at 1,000 °C), whichever is higher.

[0035] In addition, the ceramifiable compositions of the present disclosure can be ceramified into self-supporting structures, i.e., the ceramified, self-supporting structures remain rigid and do not undergo significant heat induced deformation or flow. For example, the ceramifiable compositions of the present disclosure can be configured to form self- supporting structures upon heating the ceramifiable composition to a temperature in a range from about 350 °C to about 1,000 °C, from about 350 °C to about 900 °C, or from about 350 °C to about 850 °C. Further, such self-supporting structures can be formed in a relatively shortperiod of time upon exposure to the elevated temperatures such as within about 5 minutes (300 seconds). In other aspects, such self-supporting structures can be formed upon exposure to the elevated temperatures on or after 300 seconds. In some aspects, such self-supporting structures, when aged at 350 °C for about 10 minutes, can have a flexural strength of greater than or equal to 75 psi.

[0036] As explained above, the organic polymer that can be used for ceramifiable compositions of the present disclosure include reactive organic polymers, and generally non- reactive organic polymers. The reactive organic polymers more readily decompose into carbonyl or hydroxyl containing compounds upon exposure to elevated temperatures and thus generally allow formation of a ceramified composition at lower temperatures. For example, when the ceramifiable composition includes a reactive organic polymer, the ceramifiable composition can be configured to form a self-supporting structure upon heating it to a temperature in a range of from about 350 °C to about 1000 °C to form a self-supporting structure, such as from about 350 °C to about 900 °C or from about 350 °C to about 850 °C. When the ceramifiable composition includes a non-reactive organic polymer, higher temperatures are generally employed to form the ceramified composition, e.g., the ceramifiable composition can be configured to form a self-supporting structure upon heating it to a temperature in a range of from about 650 °C to about 1000 °C or from about 650 °C to about 900 °C to form a self-supporting structure. In either case, self-supporting structures can be formed in a relatively short period of time, e.g., on or after 300 seconds.EXAMPLES

[0037] 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.

[0038] Samples of ceramifiable compositions according to the present disclosure were prepared by mixing all raw materials in a twin screw extruder (18 or 27 mm, L / D = 60). Polymers or polymer blends were fed at the main feed (barrel 1). The ceramifiable additives (silica and sodium carbonate for these experiments) and other powder additives (antioxidant, flame retardant, etc.) if any, were pre-mixed and side-fed after the first mixing zone (barrel 4). The glass fiber was side-fed after the second mixing zone (barrel 7). The extruder screw rotated at 350 rpm. Typical extrusion temperature profile of the selected polymer or polymer blendwas used. The extrudate was cooled on the belt and pelletized, for later injection or compression molding.

[0039] Example 1

[0040] A number of ceramifiable compositions were prepared and are denoted Compositions A-D in Table 1 below. The ceramifiable compositions included recycled polyvinyl butyral (PVB) as the organic polymer, glass fibers, an amorphous silica and sodium carbonate as the alkaline compound. An antioxidant and Wollastonite were also included in certain compositions. The total content of filler (glass fiber, silica, sodium carbonate and wollastonite) was kept constant at 60% by weight. The flexural strength of the ceramic structure, which was formed after exposing the compositions to elevated temperatures as described in the Ceramification Test below, was determined after cooling the samples to room temperature. It was observed that all samples (Compositions A-D) showed good thermal shock resistance, where no cracks were observed during the cooling to room temperature.

[0041] Comparative Examples

[0042] Comparative compositions were also prepared using the same apparatus and process as described above. The comparative Compositions E* and F* are provided in Table 1 below.Table 1

[0043] Ceramification test

[0044] The ceramification test was carried out by placing a sample composition in a preheated muffle furnace at temperatures of 350 °C, 450 °C, 550 °C, and 1000 °C for 10 minutes, then taken out of the muffle furnace and air-cooled. The nominal size of the sample (length x width x height) was 25.4 mm x 12.7 mm x 3.2 mm.

[0045] Flexural strength of ceramic structure

[0046] The flexural strength of the ceramic structure formed after exposure to elevated temperatures is determined by three-point bend test. A span length of 18 mm and cross head speed of 0.2 mm / minute were used.

[0047] The flexural strength of ceramic structures formed after exposure to different elevated temperatures of Compositions A through D were all higher than 75 psi. Comparative Composition E*, which contains the ceramifiable additives (silica and sodium carbonate) but no glass fiber could not form a cohesive ceramic structure after exposure to elevated temperatures. After exposure to elevated temperatures, only a thin friable crust remained for comparative Composition E*. This indicates that glass fiber serves as a refractory building block and was critical to the formation of a stable ceramic structure. The comparative Composition F* contained glass fiber but lacked the amorphous silica and the alkaline compound sodium carbonate. While comparative Composition F* could form a cohesive structure after exposure to elevated temperature of 1000 °C, the sample shrank more than 50%, and flexural strength could not be measured. At 350 °C, a small portion of polymer residue might still be present to loosely connect the glass fibers for this comparative composition. However, the formed structure was highly nonuniform and contained large pores, manifesting in a large standard deviation of the test results (almost 100% of the mean value).

[0048] In contrast to the comparative Compositions E* and F*, samples prepared from Compositions A through D not only formed a strong ceramic structure after exposure to elevated temperatures, but also maintained their dimensions with very little shrinkage (<5%). It is believed that the free silanol groups on the surface of the silica were able to react with free silanol groups on other silica and / or glass fiber surfaces to quickly build-up a silicate glass network that prevents the glass fiber in the compositions from shrinking at temperatures above its soften point. It is believed that the alkaline compound sodium carbonate can facilitate the silanol condensation reaction.

[0049] Example 2

[0050] Table 2 below reports the flexural strength of ceramic structures formed after exposure to different elevated temperatures of compositions with different glass fiber content. The ceramifiable additives (silica and sodium carbonate) were kept constant at 10% by weight.Table 2

[0051] As shown by the data of Table 2, the flexural strength of ceramic structures formed after exposure to different elevated temperatures of Compositions G and H are all higher than 75 psi. While the comparative Composition I*, which contained 10% glass fiber by weight, formed very weak ceramic structure after exposure to elevated temperatures. Even at 1000 °C, the flexural strength of formed ceramic structure based on comparative Composition I* was only 65 psi. The data in Table 2 indicate compositions having from about 30 wt%, and greater, of glass fiber, based on a total weight of the ceramifiable composition, exhibit significantly improved flexural strength compared to a composition with less than 30 wt% glass fiber (i.e., Composition I* in Table 2).

[0052] Example 3

[0053] Table 3 below reports the flexural strength of ceramic structures formed after exposure to different elevated temperatures of compositions with different types of silica. The ceramifiable additives (silica and sodium carbonate) were kept constant at 10% by weight and total glass fiber and ceramifiable additives were kept at 50% by weight.Table 3

[0054] The flexural strength of ceramic structures formed after exposure to different elevated temperatures of Compositions J, K and L are all higher than 75 psi. While the comparative Composition M*, which contains glass fiber but lacked ceramifiable additives (silica and sodium carbonate for this example) was not able to form a cohesive ceramic structure at low ceramifiable temperatures (e.g., 450 C° and 550 °C). Moreover, even though comparative Composition M* formed ceramic structure after exposure to elevated temperature of 1000 °C, its flexural strength was significantly less than the ceramifiable Compositions J, K and L.

[0055] Example 4

[0056] It is known that an alkaline compound can catalyze silanol condensation reaction. However, higher alkaline content could also weaken the silicate glass network. A number of compositions with various silica to metal carbonate molar ratios were prepared and are shown in Table 4. The total content of filler (glass fiber, silica, and sodium carbonate) was kept constant at 57.59% by weight. The flexural strength of the ceramic structure formed was determined as described above after cooling the samples to room temperature. The Figure is aplot of flexural strength versus a molar ratio of silica to alkaline compound in ceramifiable compositions after exposing the compositions to different elevated temperatures. As illustrated in the FIG., the flexural strength of ceramic structures formed after exposing ceramifiable compositions of the present disclosure to different elevated temperatures can depend on the silica to sodium carbonate molar ratio. The flexural strength increased with silica to sodium carbonate molar ratio first, then decreased at higher ratios. At the lower molar ratio, silica content was low, and there was smaller amount of free silanol groups available to bind glass fiber together, resulting in formation of a relatively weak ceramic structure. Higher sodium carbonate content also likely led to higher sodium content incorporated into silicate glass network, thus weakening the final ceramic structure. As the molar ratio (silica content) increased, flexural strength increased. However, at molar ratio of 6:1, the flexural strength of ceramic structure formed after exposure to elevated temperatures decreased. At the higher molar ratios, the amount of sodium carbonate, which could serve as a base to catalyze the silanol condensation, was low. The decrease in flexural strength was likely due to a slower silanol condensation reaction among silica and glass fibers. Therefore, there seems to be a certain silica to metal carbonate molar ratio that leads to a relative 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.Table 4

[0057] Example 5

[0058] Formation of self-supporting structure that will not undergo significant flow or deformation during a fire is a consideration for a flame barrier material. A number of compositions (see Table 5 below) were prepared and tested according to UL 94 flammability test. While samples were not able to achieve a UL 94 V-0 rating, all samples with ceramifiable additives (silica and sodium carbonate) did not drip during the test. The comparative samplewithout ceramifiable additives (Composition T*) dripped during the test. This indicates that the ceramifiable additives enable samples to form a ceramic structure that could support its own weight and resist flow induced deformation.Table 5

[0059] 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 and is 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 ceramifiable composition, comprising:(a) an organic polymer;(b) a silica;(c) an alkaline compound; and(d) from about 30 wt% to about 80 wt% of a glass fiber, based on a total weight of the ceramifiable composition.

2. The ceramifiable composition of claim 1, wherein the composition comprises the organic polymer in a range of from about 20 wt% to about 60 wt% based on the total weight of the ceramifiable composition.

3. The ceramifiable composition of claim 1 or claim 2, wherein the organic polymer comprises a reactive polymer.

4. The ceramifiable composition of claim 3, wherein the reactive polymer comprises polyvinyl butyral, recycled polyvinyl butyral, a polyamide, a thermoplastic polyurethane, an aliphatic polyketone, a polycarbonate, a polyester, a polyethylene terephthalate, a polybutylene terephthalate, polyetheretherketone, polyetherketoneketone, polyetherketone, polyphenylene sulfide, a polyvinyl alcohol, a polyvinyl acetate, an ethylene-vinyl alcohol copolymer, an ethylene-vinyl acetate copolymer, or any combination thereof.

5. The ceramifiable composition of any one of the preceding claims, wherein the silica comprises fumed silica, silica gel, precipitated silica, amorphous silica, or any combination thereof.

6. The ceramifiable composition of claim 5, wherein the silica has a diameter in a range of from about 3 nm to about 150 nm.

7. The ceramifiable composition of any one of the preceding claims, wherein the composition comprises silica in a range of from about 2 wt% to about 10 wt% based on the total weight of the ceramifiable composition.

8. The ceramifiable composition of any one of the preceding claims, wherein the alkaline compound comprises sodium carbonate, calcium carbonate, potassium carbonate, hydrotalcite, or any combination thereof.

9. The ceramifiable composition of any one of the preceding claims, wherein the composition comprises the alkaline compound in a range of from about 0.5 wt% to about 10 wt%, based on the total weight of the ceramifiable composition.

10. The ceramifiable composition of any one of the preceding claims, wherein a molar ratio of silica to alkaline compound is from about 1.5: 1 to about 6: 1.

11. The ceramifiable composition of any one of the preceding claims, wherein the ceramifiable composition includes about 30 wt% to about 70 wt% of a glass fiber, based on a total weight of the ceramifiable composition.

12. The ceramifiable composition of any one of the preceding claims, wherein the glass fiber comprises E-glass, A-glass, C-glass, D-glass, S-glass, ECR-glass, AR glass, R-glass, or any combination thereof.

13. The ceramifiable composition of claim 12, wherein the glass fiber has an average length in a range of from about 0.3 cm to about 1.5 cm.

14. The ceramifiable composition of any one of the preceding claims, wherein the glass fiber has a softening point of greater than or equal to 700 °C.

15. The ceramifiable composition of any one of the preceding claims, wherein the glass fiber comprises glass fiber reinforced long fiber thermoplastic.

16. The ceramifiable composition of claim 15, wherein the average length of glass fiber in glass fiber reinforced long fiber thermoplastic is in the range of 5 mm to 25 mm.

17. The ceramifiable composition of any one of the preceding claims, wherein the ceramifiable composition further comprises, based on the total weight of the composition, greater than 0 wt% to about 20 wt% additives, the additives comprising metal silicates, calciumsilicates, magnesium silicates, aluminum silicates, wollastonite, sepiolite, or any combination thereof.

18. The ceramifiable composition of any one of the preceding claims, wherein the composition is configured to form a self-supporting structure upon exposure at or above about 350 °C.

19. The ceramifiable composition of any one of the preceding claims, wherein the composition is configured to form a self-supporting structure upon exposure to a temperature in a range of from about 350 °C to about 1,000 °C.

20. The ceramifiable composition of any one of the preceding claims, wherein the composition is configured to form a self-supporting structure upon exposure to a temperature in a range of from about 350 °C to about 900 °C.

21. The ceramifiable composition of any one of the preceding claims, wherein the composition is configured to form a self-supporting structure upon exposure to a temperature in a range of from about 350 °C to about 850 °C.

22. The ceramifiable composition of any one of claims 18-21, wherein the composition is configured to form the self-supporting structure upon exposure to the temperature on or after 300 seconds.

23. The ceramifiable composition of any one of claims 18-22, wherein the self- supporting structure when aged at 350° C for about 10 minutes has a flexural strength of greater than or equal to 75 psi.

24. The cermifiable composition of any one of the preceding claims, wherein the silica has a surface and free silanol groups located on the surface.

25. The ceramifiable composition of any one of the preceding claims, wherein the silica comprises silica gel.

26. A molded article comprising, the ceramifiable composition of any one of the preceding claims.

27. A battery enclosure comprising, the ceramifiable composition of any one of the preceding claims.

28. A method of preparing a ceramified composition comprising: providing a ceramifiable composition, comprising:(a) an organic polymer;(b) a silica;(c) an alkaline compound; and(d) from about 30 wt% to about 70 wt% of a glass fiber, based on a total weight of the composition; and heating the ceramifiable composition to a temperature of at least about 350 °C to form a self-supporting structure.

29. The method of claim 28, wherein the ceramifiable composition is heated to a temperature of from about 350 °C to about 1000 °C.

30. The method of claim 28, wherein the ceramifiable composition is heated to a temperature of from about 350 °C to about 900 °C.

31. The method of claim 28, wherein the ceramifiable composition is heated to a temperature of from about 350 °C to about 850 °C.

32. A method of preparing a ceramifiable composition comprising: combining: (a) an organic polymer; (b) a silica; (c) an alkaline compound; and (d) from about 30 wt% to about 70 wt% of a glass fiber, based on a total weight of the ceramifiable composition, to form the ceramifiable composition.

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