A process for preparing a composition, the composition, a composite prepared therefrom, and a process for preparing the composite

Abstract

A process for preparing a composition comprising a) adding a dianhydride and diamine to a filler, and b) mixing the materials. The dianhydride and diamine may each comprise at least one aromatic ring

Description

The present invention relates to a process for preparing a composition, the composition, a composite prepared therefrom, and a process for preparing the composite Background to the Invention It is known to incorporate an inorganic filler, for example mica, into a polymeric material, such as polytetrafluoroethylene (PTFE), to form an article. Such articles typically exhibit improved creep resistance, stiffness and hardness relative to polymeric materials which do not contain an inorganic filler. However, disadvantageously, such articles may also exhibit diminished mechanical properties, such as reduced ductility and toughness. In some known article, the disadvantages are so pronounced that, following normal use, the articles become too brittle and exhibit a significant drop in impact resistance and elongation, resulting in the article being of no practical use. Attempts have been made to ameliorate the disadvantages of such articles. For example, published research includes attempts to enhance the compatibility of the inorganic filler into the polymeric material. Publications describe the incorporation of a surface modifier for the inorganic filler which may be in the form of a coating applied to the inorganic filler during a separate pre-treatment stage or added to the mixture of the inorganic filler and polymeric material during processing. Generally, a surface modifier may be a coupling or a non-coupling modifier. With respect to non-coupling surface modifiers, the surface modifier will interact with the surface of the inorganic filler particles but not with the polymeric material. Coupling surface modifiers tend to interact strongly with both the surface of the inorganic filler particles and the polymeric material. Modifiers comprising acid functional groups may be classed as non-coupling modifiers and coupling modifiers, and are a commonly used modifier in related chemistry. Fatty acids may be considered to be a non-coupling modifier. The carboxylic acid group binds strongly to the surface of the inorganic filler particles, while the ‘fatty’ group intercolates with the polymeric material. Polymeric acids are generally regarded as a coupling surface modifier. The carboxy group can interact strongly with the surface of the inorganic filler particles, and the polymeric chain can interact strongly with the polymeric material. Many variables enhance or diminish the extent of the interaction, for example the functionality of the surface modifier and the type of polymeric material may affect the interaction. Moreover, many compounds comprising acid functional groups exhibit volatility during processing which is a distinct disadvantage in using such compounds. Further, it is known to add a coupling agent to a reaction between an inorganic filler, for example mica, and a polymeric material, such as PTFE, to form an article. However, known coupling agents are not able to withstand the elevated temperatures required for the processing of many polymeric materials, such as PTFE. The relative inability of known coupling agents to withstand elevated temperatures is considered to be due to the organic moiety of the coupling agent being a low molecular alkane having an amino or epoxy group. For example, it has been found that silane, Titanate and Zirconate coupling agents which comprise a low molecular weight alkane moiety with an amino or epoxy group cannot withstand high temperatures, for example up to 300°C. At elevated temperatures such as around 300°C, the silane may undergo unwanted reactions, which can lead to a loss of bonding effectiveness and could compromise the properties of the composite material. Moreover, many polymeric materials, for example PTFE, are difficult to process due to the relative inertness of such materials. Thus, suitable coupling agents and inorganic fillers must be carefully considered so as to obtain the required bond between the coupling agent, inorganic filler and polymeric material to form a reliable and usable article which does not suffer from the above mentioned diminished mechanical properties. Disadvantageously, articles formed as described above, for example, may involve multi-step processes, which often increases the time and cost of the overall process to form the article, also to the detriment of the efficiency of the overall process. It is an object of embodiments of the present invention to at least partially overcome or alleviate the above problems and / or to provide an improved composition, process for preparing the composition, article prepared therefrom, and a process for preparing the article. Summary of the Invention The present invention concerns a process for preparing a composition. The process may comprise step (a), adding a dianhydride and diamine monomer of an aromatic polyimide to a filler. The process may comprise step (b), in situ mixing the components of step (a) to form the composition. According to a broad aspect of the present invention, there is provided a process for preparing a composition, the process comprising: (a) adding a dianhydride and diamine monomer of an aromatic polyimide to a filler. The composition may be for reacting with a plastic material, for example epoxy resin, for example IN2® Epoxy Infusion Resin, Polytetrafluoroethylene (PTFE), or Bisphenol-A diglycidyl ether (E51). IN2® Epoxy Infusion Resin is a mix of bis-[4-(2,3-epoxipropoxi)phenyl]propane, Phenolic epoxy resin F-44, l,6-bis(2,3- epoxypropoxy)hexane and propylene carbonate, and may be obtained from Easy Composites Ltd, United Kingdom. The composition may be for reacting with a plastic material, for example epoxy resin, for example IN2® Epoxy Infusion Resin, in combination with a companion hardener. The companion hardener may be a formulated amine mixture. The formulated amine mixture may comprise 3-aminomethyl-3,5,5-trimethylcyclohexylamine, Poly[oxy(methyl-l,2-ethanediyl)], a-(2-aminomethylethyl)-co-(2- aminomethylethoxy)-, 2,2,4 (or 2,4,4)-trimethylhexane-l,6-diamine, and benzyl alcohol. The composition may be for reacting with a plastic material, for example epoxy resin, for example Bisphenol-A diglycidyl ether (E51), in combination with a companion hardener. The companion hardener may be methyl tetrahydrophthalic anhydride. PTFE may be in the form of a powder. Advantageously, the present invention provides a composition which may be used as a coupling agent for reaction with a plastic material, for example epoxy or PTFE. The composition may be for a coupling agent for reaction with a plastic material. Advantageously, the composition provides enhanced mechanical properties compared to known compositions in thermoset epoxy composites, in particular when mica and / or graphite are used as fillers. Beneficially, the composition can withstand elevated temperatures, for example over 300°C, which are typically required when processing plastic materials, such as epoxy or PTFE. As such, the composition finds broad applicability as a coupling agent used in the processing of such plastic materials. Without being bound by theory, it is considered that the ability of the composition to withstand elevated temperatures is at least in part due to the presence of an aromatic polyimide group. As such, the composition of the present invention allows for the formation of a composite of a plastic material, such as epoxy or PTFE, which has a higher, or even significantly higher, filler content than that of known plastic material composites, for example those formed using a filler, such as mica, and PTFE. This in turn means that, beneficially, the composition of the present invention provides a noticeable improvement in mechanical properties of an article subsequently formed using such a composite. In particular, it has been found that such articles exhibit improved creep resistance, stiffness, hardness, ductility and toughness relative to known plastic material composites, for example those formed using a filler, such as mica, and PTFE, without the composition of the invention. It follows that such articles do not become too brittle or exhibit a significant drop in impact resistance and elongation, and, therefore, remain of practical use for longer periods of time compared to known plastic material composites, for example those formed using a filler, such as mica, and PTFE, without the composition of the invention. Moreover, in embodiments, comprising, step (b), mixing the components of step (a) in situ to form the composition, the composition is formed ‘in-situ’. Advantageously, this in-situ synthesis allows for the direct formation of the aromatic polyimide on the filler surface, which can lead to uniform distribution of the aromatic polyimide on the filler surface, and prevent particle agglomeration. The in-situ process promotes strong adhesion and bonding between the aromatic polyimide coupling agent and the filler. It is understood that this is due to the aromatic polyimide forming directly on the filler surface. Furthermore, the two step process (i.e., step (a) of adding the components, and step (b) of mixing the components in situ) can also lead to a strong interaction between the composition and a polymer matrix, for example PTFE, which can enhance mechanical properties and improve distribution in the composite. Even further, the in-situ synthesis may be a one-step process, therefore greatly simplifying the surface treatment process compared to conventional methods. This can be advantageous, not least in terms of time, cost, and overall efficiency, compared to ex-situ methods where pre-made materials are required to be combined. Further advantageously, the composition forms a strong bond with relatively inert plastic materials. Such relatively inert materials are typically difficult to process when using known coupling agents to form end-product articles. Typically, when processing a relatively inert plastic material with a known coupling agent, the processing may require reaction conditions including high temperatures, relatively strong concentrations of acid or alkali, and long processing times. Each of these factors may lead to costly and time consuming processes which are not cost effective for a manufacturer. Moreover, the use of relatively strong acid or alkali to promote a required reaction with the relatively inert plastic material equates to the use of volatile materials which require careful handling and storage, and which need to be used by an operator of significant skill. As such, these factors can also lead to increased cost and complexity of such processing. The present invention overcomes such disadvantages of the prior art by forming a strong bond with relatively inert plastic materials. As such, the complexity, cost, time of processing and ease of processing relatively inert materials with the composition of the present invention may be reduced, even significantly reduced. Without being bound by theory, it is believed that the relatively strong bond is formed because the aromatic polyimide and the relatively inert plastic material, for example PTFE, form a strong interface between one another, and because the aromatic polyimide introduces more nitrogen, oxygen and hydrogen elements which are able to form chemical bonds with the fluorine of the plastic material, for example PTFE, which has a high electrondonating property. Conventional coupling agents, such as those comprising silanes, typically emit volatile organic compounds (VOCs), including alcohols, during surface treatment. In contrast, the in situ process of the invention produces only water as a byproduct, resulting in zero VOC emissions. As such, advantageously, the in situ process of the invention is both zero-VOC producing, and environmentally friendly. Furthermore, water is employed as one of the solvents throughout the surface treatment process, further reducing environmental impact. Any solvents which may be used in the process can be fully recycled and reused, ensuring resource efficiency and minimising waste during surface treatment. Advantageously, the composition of the present invention finds applicability as a coupling agent in the treatment of relatively inert graphite particles to form composite materials having enhanced thermal and electrical conductivity, such as a lubricant or as a graphite anode in a battery. Despite extensive research, known coupling agents have not been found to effectively treat and be processable with relatively inert graphite. Thus, as the composition of the present invention can be used in the treatment of relatively inert graphite particles, this considerably increases the broad range of applicability of the composition of the present invention. Without being bound by theory, it is believed that known coupling agents have not been found to effectively treat and be processable with relatively inert graphite because in graphite, each carbon atom is bonded to three other carbon atoms, leaving one electron in a delocalized state (^-electrons). These delocalized electrons spread over the entire structure and stabilize the material, making it difficult for chemical reagents to interact with the carbon atoms. This structure makes the surface of graphite lacking active or reactive functional groups, such as hydroxyl (-OH), carboxyl (-COOH), or amino (-NIL) groups, which are often found in other materials. Further advantageously, the composition of the present invention can be applied to treat other graphite structure materials such as carbon fibre and carbon, which is wildly used in composite materials, and also applied to treat steel and ceramic powders. The process may comprise: (b) In situ mixing the components of step (a) to form the composition. Accordingly, in a first aspect of the invention, there is provided a process for preparing a composition, the process comprising the steps: (a) Adding dianhydride and diamine monomer of an aromatic polyimide to a filler, (b) In situ mixing the components of step (a) to form the composition. Advantageously, the filler may further enhance the beneficial mechanical properties of an article formed from a composite of the composition and a plastic material. In particular, such articles may exhibit improved creep resistance, stiffness, hardness, ductility and toughness relative to known plastic material composites, for example those formed using a filler, such as mica, and PTFE, without the composition of the invention. Such articles, therefore, do not become too brittle or exhibit a significant drop in impact resistance and elongation, and, therefore, remain of practical use for longer periods of time compared to known plastic material composites, for example those formed using a filler, such as mica, and PTFE, without the composition of the invention. The filler may be a filler selected from the group consisting of a carbonate, a silicate, a sulphate mineral, a carbon, a metallic filler, an oxide, a phosphate, a nitride, a carbide, a borate, a phyllosilicate, and a glass filler. The carbonate may be a carbonate selected from the group consisting of calcium carbonate and magnesium carbonate. The silicate mineral may be a silicate mineral selected from the group consisting of talc, mica, clay, glass fibre, glass powder, and calcium silicate. In some embodiments, the mica may be Sericite mica powder. The Sericite mica powder may have a whiteness (WB) of 77-79, an average particle size of 13-16 pm, a 325 mesh sieve residue of <0.2% and a pH of 4-7. The sulphate mineral may be a sulphate mineral selected from the group consisting of gypsum, barium sulphate and calcium sulphate. The carbon may be a carbon material selected from the group consisting of carbon black, graphite, graphene, carbon nanotubes (CNTs), and carbon fibres. The metallic filler may be a metallic filler selected from the group consisting of iron powder, iron fibre, bronze, aluminium, and copper. The aluminium may be an aluminium powder. The oxide may be an oxide selected from the group consisting of silica, alumina, titanium dioxide, and zinc oxide. The phosphate may be a phosphate selected from the group consisting of calcium phosphate, and aluminium phosphate. The nitride may be silicon nitride or boron nitride. The carbide may be silicon carbide. The borate may be a borate selected from the group consisting of boric acid and sodium borate (borax). The phyllosilicate may be a phyllosilicate selected from the group consisting of bentonite, and serpentine. The glass filler may be a glass filler selected from the group consisting of glass fibre, glass beads, glass microspheres, and glass powder. The filler may be a disulphide, for example molybdenum disulphide or tungsten disulphide. The filler may be a ceramic powder. The filler may be selected from the group comprising a polymeric powder, for example a fluoropolymer (such as PTFE or PVDF), a polyolefin wax, an Ultra-High Molecular Weight Polyethylene (UHMWPE), a high-temperature engineering polymer (such as PEEK or PPS), silicone (such as PMSQ) spheres, acrylic microspheres, styrenic microspheres, expandable / hollow polymer microspheres, aramid pulp, biobased cellulose fibrils, and TPU elastomer powders, and combinations thereof. The filler may be PTFE. The PTFE may be a PTFE homopolymer, for example Fluon® G163 (obtained from AGC Inc.) which is a virgin granular PTFE homopolymer. The PTFE may be Fluon® FL1710Z (obtained from AGC Inc.) which is a white, finely-divided, low molecular weight powder manufactured from virgin PTFE feedstock. The PTFE may be Fluon+™ FL 1680 (obtained from AGC Inc.) which is a white, finely divided, low molecular weight powder manufactured from virgin PTFE feedstock. In some embodiments, the PTFE may be PTFE micro powder. The PTFE micro powder may have an average particle size from 1.5 to 200 pm. The filler may be in the form of a powder. The filler may be in the form of particles, such that the filler may be an inorganic particulate material. Advantageously, an inorganic particulate material has an increased surface area for reactivity, and also has advantages of ease of processing, beneficial isotropic properties (equal properties in all directions), flexible use in different composites, and cost-effectiveness. The filler may be in the form of fibres. The filler may be in the form of one or more selected from a group consisting of a powder, particles and fibres. The aromatic polyimide may be formed by reacting a dianhydride with a diamine. The dianhydride may be an organic acid dianhydride, for example a carboxylic dianhydride. The dianhydride may be a cyclic compound comprising one, two, three, four, five, or more than five, rings. The dianhydride may be a cyclic compound comprising at least one, two, three, four, five, or at least six, rings. The dianhydride may be a cyclic compound comprising no more than one, two, three, four, five, or no more than six, rings. Advantageously, in embodiments comprising a dianhydride as a cyclic compound, the aromatic polyimide and, therefore, the composition, exhibit enhanced thermal stability due to the high-temperature resistance of the cyclic dianhydride which, therefore, makes any composite comprising the composition even more heat resistant. The diamine may be a cyclic compound comprising one, two, three, four, five, or more than five, rings. The diamine may be a cyclic compound comprising at least one, two, three, four, five, or at least six, rings. The diamine may be a cyclic compound comprising no more than one, two, three, four, five, or no more than six, rings. Advantageously, in embodiments comprising a diamine as a cyclic compound, the aromatic polyimide and, therefore, the composition, exhibit enhanced thermal stability due to the high-temperature resistance of the cyclic diamine which, therefore, makes any composite comprising the composition even more heat resistant. The dianhydride may comprise one, two, three, four, five, or more than five, aromatic rings. The dianhydride may comprise at least one, two, three, four, five, or at least six five, aromatic rings. The dianhydride may comprise no more than one, two, three, four, five, or no more than six, aromatic rings. The diamine may comprise one, two, three, four, five, or more than five, aromatic rings. The diamine may comprise at least one, two, three, four, five, or at least six five, aromatic rings. The diamine may comprise no more than one, two, three, four, five, or no more than six, aromatic rings. The dianhydride may comprise one, two, three, four, five, or more than five, heterocyclic rings. The dianhydride may comprise at least one, two, three, four, five, or at least six, heterocyclic rings. The dianhydride may comprise no more than one, two, three, four, five, or no more than six, heterocyclic rings. The at least one heterocyclic ring may comprise at least one aromatic heterocyclic ring. The at least one heterocyclic ring may comprise at least one non-aromatic heterocyclic ring. The diamine may comprise one, two, three, four, five, or more than five, heterocyclic rings. The diamine may comprise at least one, two, three, four, five, or at least six, heterocyclic rings. The diamine may comprise no more than one, two, three, four, five, or no more than six, heterocyclic rings. The at least one heterocyclic ring may comprise at least one aromatic heterocyclic ring. The at least one heterocyclic ring may comprise at least one non-aromatic heterocyclic ring. The dianhydride may comprise a biphenyl group. The diamine may comprise a biphenyl group. The dianhydride may comprise a phenyl group bonded to at least one moiety comprising anhydride group. The diamine may comprise at least one functional group selected from the group consisting of diphenyl ether, diphenyl sulphide, and diphenyl alkane. The diphenyl alkane may be selected from the group consisting of diphenylmethane, 1,1-Diphenylethane, 1,2-Diphenylethane, and 1,3-Diphenylpropane. The dianhydride may be selected from the group consisting of pyromellitic dianhydride, 3,3',4,4'-Biphenyltetracarboxylic dianhydride, and 4,4'-Oxydiphthalic anhydride. The diamine may be selected from the group consisting of p-Phenylenediamine, m-Phenylenediamine, 4,4'-Oxydianiline, 3,4'-Oxydianiline, and 4,4'-Diaminodiphenylmethane. The composition may be a polyimide according to compound 1: Compound 1 wherein: Ri may represent the residue of a dianhydride; R2 may represent the residue of a diamine; In some embodiments comprising Compound 1, n may be any integer from about 1 to about 10. For example, n may be selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. In some embodiments comprising Compound 1, n may be 1. In some embodiments comprising Compound 1, Ri may represent the residue of a dianhydride comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 1, R2 may represent the residue of a diamine comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. The filler may be present in an amount of from about 70.0 to about 99.9 wt.%, from about 70.0 to about 99.8 wt.%, from about 70.0 to about 99.7 wt.%, from 70.0 to about 99.6 wt.%, from 70.0 to about 99.5 wt.%, from about 70.0 to about 99.5 wt.%, from about 70.0 to about 95 wt.%, from about 70.0 to about 92 wt.%, from about 70.0 to about 90 wt.%, from about 70.0 to about 87 wt.%, from about 70.0 to about 84 wt.%, from about 70.0 to about 80 wt.%, or from about 70.0 to about 75 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 75.0 to about 99.9 wt.%, from about 75.0 to about 99.8 wt.%, from about 75.0 to about 99.7 wt.%, from 75.0 to about 99.6 wt.%, from about 75.0 to about 99.5 wt.%, from about 75.0 to about 92 wt.%, from about 75.0 to about 90 wt.%, from about 75.0 to about 84 wt.%, or from about 75.0 to about 80 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 80.0 to about 99.9 wt.%, from about 80.0 to about 99.8 wt.%, from about 80.0 to about 99.7 wt.%, from 80.0 to about 99.6 wt.%, from about 80.0 to about 99.5 wt.%, from about 80.0 to about 92 wt.%, from about 80.0 to about 90 wt.%, or from about 80.0 to about 84 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 84.0 to about 99.9 wt.%, from about 84.0 to about 99.8 wt.%, from about 84.0 to about 99.7 wt.%, from 84.0 to about 99.6 wt.%, from about 84.0 to about 99.5 wt.%, from about 84.0 to about 92 wt.%, from about 84.0 to about 90 wt.%, or from about 84.0 to about 87 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 87.0 to about 99.9 wt.%, from about 87.0 to about 99.8 wt.%, from about 87.0 to about 99.7 wt.%, from 87.0 to about 99.6 wt.%, from about 87.0 to about 99.5 wt.%, from about 87.0 to about 95 wt.%, from about 87.0 to about 92 wt.%, or from about 87.0 to about 90 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 90.0 to about 99.9 wt.%, from about 90.0 to about 99.8 wt.%, from about 90.0 to about 99.7 wt.%, from 90.0 to about 99.6 wt.%, from about 90.0 to about 99.5 wt.%, from about 90.0 to about 95 wt.%, or from about 90.0 to about 92 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 92.0 to about 99.9 wt.%, from about 92.0 to about 99.8 wt.%, from about 92.0 to about 99.7 wt.%, from 92.0 to about 99.6 wt.%, from about 92.0 to about 99.5 wt.%, or from about 92.0 to about 95 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of from about 95.0 to about 99.9 wt.%, from about 95.0 to about 99.8 wt.%, from about 95.0 to about 99.7 wt.%, from 95.0 to about 99.6 wt.%, from about 95.0 to about 99.5 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of about 70.0 wt.%, about 74.0 wt.%, about 78.0 wt.%, about 80.0 wt.%, about 84.0 wt.%, about 88.0 wt.%, about 90.0 wt.%, about 94.0 wt.%, about 99.5 wt.%, about 99.6 wt.%, about 99.7 wt.%, about 99.8 wt.%, or about 99.9 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of at least about 70.0 wt.%, about 74.0 wt.%, about 78.0 wt.%, about 80.0 wt.%, about 84.0 wt.%, about 88.0 wt.%, about 90.0 wt.%, about 94.0 wt.%, about 99.5 wt.%, about 99.6 wt.%, about 99.7 wt.%, about 99.8 wt.%, or at least about 99.9 wt.%, based on the total weight of the components reacted in step (a). The filler may be present in an amount of no more than about 70.0 wt.%, about 74.0 wt.%, about 78.0 wt.%, about 80.0 wt.%, about 84.0 wt.%, about 88.0 wt.%, about 90.0 wt.%, about 94.0 wt.%, about 99.5 wt.%, about 99.6 wt.%, about 99.7 wt.%, about 99.8 wt.%, or no more than about 99.9 wt.%, based on the total weight of the components reacted in step (a). Step (a) may further comprise adding a solvent. The solvent may be added to the dianhydride and diamine monomer simultaneously, or before one and after the other, or before both. The solvent may be a solvent selected from the group consisting of N-Methylpyrrolidone, N,N-Dimethylformamide, N,N-dimethylacetamide, Dimethyl Sulfoxide, Chloroform, Tetrahydrofuran, Ethanol, and water. The solvent may be present in an amount of from about 5.0 to about 25.0 wt.%, from about 5.0 to about 20.0 wt.%, from about 5.0 to about 15.0 wt.%, or from about 5.0 to about 10.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of from about 10.0 to about 25.0 wt.%, from about 10.0 to about 20.0 wt.%, or from about 10.0 to about 15.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of from about 15.0 to about 25.0 wt.%, or from about 15.0 to about 20.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of from about 20.0 to about 25.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of about 5.0 wt.%, about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, or about 25.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of at least about 5.0 wt.%, about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, or at least about 25.0 wt.%, based on the total weight of the components reacted in step (a). The solvent may be present in an amount of no more than about 5.0 wt.%, about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, or no more than about 25.0 wt.%, based on the total weight of the components reacted in step (a). Each component of step (a) may be added to a reaction container suitable for mixing the components of step (a). For example, the components of step (a) may be added to a blender, for example, a high-speed multi-functional electric grain grinder, power: 900W, capacity: 150g. The mixing of step (b) may be carried out at from about 5000 rpm to about 25,000 rpm, for example about 5000 rpm, about 10,000 rpm, about 15,000 rpm, about 20,000 rpm, about 22,000 rpm, or about 25,000 rpm. Step (b) may include mixing the components of step (a) for from about 1 minute to about 30 minutes, from about 1 minute to about 20 minutes, from about 1 minute to about 10 minutes, or from about 1 minute to about 5 minutes. Step (b) may include mixing the components of step (a) for from about 5 minutes to about 30 minutes, from about 5 minutes to about 20 minutes, or from about 5 minutes to about 10 minutes. Step (b) may include mixing the components of step (a) for from about 10 minutes to about 30 minutes, from about 10 minutes to about 20 minutes, or from about 10 minutes to about 15 minutes. Step (b) may include mixing the components of step (a) for from about 15 minutes to about 30 minutes, or from about 15 minutes to about 20 minutes. Step (b) may include mixing the components of step (a) for from about 20 minutes to about 30 minutes, or from about 20 minutes to about 25 minutes. Step (b) may include mixing the components of step (a) for from about 25 minutes to about 30 minutes. Step (b) may include mixing the components of step (a) for about 1 minute, for about 5 minutes, for about 10 minutes, for about 15 minutes, for about 20 minutes, for about 25 minutes, or for about 30 minutes. Step (b) may include mixing the components of step (a) for at least about 1 minute, for about 5 minutes, for about 10 minutes, for about 15 minutes, for about 20 minutes, for about 25 minutes, or for at least about 30 minutes. Step (b) may include mixing the components of step (a) for no more than about 1 minute, for about 5 minutes, for about 10 minutes, for about 15 minutes, for about 20 minutes, for about 25 minutes, or for no more than about 30 minutes. Step (b) may include mixing the components of step (a) at room temperature. Step (b) may include mixing the components of step (a) at a temperature above room temperature. Step (b) may include mixing the components of step (a) at a temperature above room temperature but no more than 40°C. Step (b) may include mixing the components of step (a) at a temperature above 25°C but no more than 40°C. Step (b) may include mixing the components of step (a) at a temperature of from about 0°C to about 25°C, from about 5°C to about 25°C, from about 10°C to about 25°C, or from about 15°C to about 25°C. Step (b) may include mixing the components of step (a) at a temperature of from about 0°C to about 40°C, from about 5°C to about 40°C, from about 10°C to about 40°C, or from about 15°C to about 40°C. Step (b) may include mixing the components of step (a) at a temperature of no more than about 15°C, about 20°C, about 25°C, about 30°C, about 35°C, or no more than about 40°C. The components of step (a) may be heated to an aforementioned temperature before step (b). The process may comprise, after step (b), step (c), heating the mixed components of step (a). Step (c) may comprise heating the mixed components of step (a) at room temperature. Step (c) may comprise heating the mixed components of step (a) at a temperature above room temperature. Step (c) may comprise heating the mixed components of step (a) at a temperature above room temperature but no more than 40°C. Step (c) may comprise heating the mixed components of step (a) at a temperature above 25°C but no more than 300°C. Step (c) may comprise heating the mixed components of step (a) at a temperature of from about 10°C to about 25°C, or from about 15°C to about 25°C. Step (c) may comprise heating the mixed components of step (a) at a temperature of from about 10°C to about 40°C, or from about 15°C to about 40°C. Step (c) may comprise heating the mixed components of step (a) at a temperature of no more than about 15°C, about 20°C, about 25°C, about 30°C, about 35°C, or no more than about 40°C. Step (c) may comprise heating the mixed components of step (a) at a temperature above 25°C but no more than 300°C. Step (c) may comprise heating the mixed components of step (a) at a temperature of from about 50°C to about 350°C, form about 75°C to about 325°C, from about 100°C to about 300°C, from about 125°C to about 300°C, from about 150°C to about 300°C, from about 150°C to about 275°C, from about 150°C to about 250°C, from about 150°C to about 225°C, or from about 150°C to about 200°C. Step (c) may comprise heating the mixed components of step (a) at a temperature of at least about 50°C, about 75°C, about 100°C, about 125°C, about 150°C, about 175°C, about 200°C, about 225°C, about 250°C, about 275°C, about 300°C, or at least about 325°C, up to no more than about 350°C. Advantageously, heating the mixed components of step (a) removes any solvent which may be present, and the solvent may be recycled and reused. According to a second aspect of the invention, there is provided a composition obtained by the process according to the first aspect. The composition may have a structure according to Compound 2: Compound 2 In embodiments comprising a composition having a structure according to Compound 2, Ri may represent the residue of a dianhydride, and / or R2 may represent the residue of a diamine. In some embodiments comprising Compound 2, Ri may represent the residue of a dianhydride comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 2, R2 may represent the residue of a diamine comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. According to a third aspect of the invention, there is provided a process for preparing a composite. The process for preparing the composite may comprise the steps: i. Providing a composition formed by combining an aromatic polyimide with a filler; and combining the composition with a plastic material, ii. Blending the composition and plastic material of step (i) to form a blend, iii. Heating the blend to form the composite. The composition may be a composition according to the first or second aspects of the invention. The plastic material may be a polymer, for example a thermoplastic polymer. The polymer may be any matrix with which inorganic particulate solids are employed. The polymer may be a polymer selected from the group consisting of a plastic, a resin, and a rubber material. The polymer may be a polymer selected from the group consisting of polytetrafluoroethylene, polyetheretherketone, and polyolefin. The polymer may be a polymer selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride, natural rubber, and synthetic rubber. The synthetic rubber may be a synthetic rubber selected from the group consisting of: silicon rubber, styrene-butadiene rubber, ethylene-propylene terpolymer rubber and urethane rubber, phenolic resins, epoxy resins, and combinations thereof. The thermoplastic polymer may be Polytetrafluoroethylene (PTFE). The composition of step (i) may be present in an amount of from about 10.0 to about 55.0 wt.%, from about 10.0 to about 50.0 wt.%, from about 10.0 to about 40.0 wt.%, from about 10.0 to about 30.0 wt.%, from about 10.0 to about 20.0 wt.%, or from about 10.0 to about 15.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of from about 20.0 to about 55.0 wt.%, from about 20.0 to about 50.0 wt.%, from about 20.0 to about 40.0 wt.%, from about 20.0 to about 30.0 wt.%, or from about 20.0 to about 25.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of from about 30.0 to about 55.0 wt.%, from about 30.0 to about 50.0 wt.%, from about 30.0 to about 40.0 wt.%, or from about 30.0 to about 35.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of from about 40.0 to about 55.0 wt.%, from about 40.0 to about 50.0 wt.%, or from about 40.0 to about 45.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, about 25.0 wt.%, about 30.0 wt.%, about 35.0 wt.%, about 40.0 wt.%, about 45.0, about 50.0 wt.%, or about 55.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of at least about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, about 25.0 wt.%, about 30.0 wt.%, about 35.0 wt.%, about 40.0 wt.%, about 45.0, about 50.0 wt.%, or at least about 55.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The composition of step (i) may be present in an amount of no more than about 10.0 wt.%, about 15.0 wt.%, about 20.0 wt.%, about 25.0 wt.%, about 30.0 wt.%, about 35.0 wt.%, about 40.0 wt.%, about 45.0, or about 50.0 wt.%, or no more than about 55.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). In any of the aforementioned embodiments comprising the composition of step (i) in an amount of from about 10.0 wt.% to about 55.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i), and the values stated therebetween, the plastic material may be an epoxy in an amount of from about 30.0 wt.% to about 60 wt.%, from about 35.0 wt.% to about 55 wt.%, from about 40.0 wt.% to about 50.0 wt.%, or about 45.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of from about 40.0 to about 80 wt.%, from about 40.0 to about 70.0 wt.%, from about 40.0 to about 60.0 wt.%, from about 40.0 to about 50.0 wt.%, or from about 40.0 to about 45.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of from about 50.0 to about 80 wt.%, from about 50.0 to about 70.0 wt.%, from about 50.0 to about 60.0 wt.%, or from about 50.0 to about 55.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of from about 60.0 to about 80 wt.%, from about 60.0 to about 70.0 wt.%, or from about 60.0 to about 65.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of from about 70.0 to about 80 wt.%, or from about 70.0 to about 75.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of at least about 40.0 wt.%, about 45.0 wt.%, about 50.0 wt.%, about 55.0 wt.%, about 60.0 wt.%, about 65.0 wt.%, about 70.0 wt.%, about 75.0 wt.%, or at least about 80.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The plastics material may be present in an amount of no more than about 40.0 wt.%, about 45.0 wt.%, about 50.0 wt.%, about 55.0 wt.%, about 60.0 wt.%, about 65.0 wt.%, about 70.0 wt.%, about 75.0 wt.%, or no more than about 80.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i). The process may include, after step (ii) and before step (iii), pressing the blend of components. The blend of components may be pressed using a hydraulic press. The blend of components may be pressed at a pressure of from about 20 to about 120 MPa, for example about 30 to about 100 MPa, about 30 MPa, about 40 MPa, about 50 MPa, about 60 MPa, about 70 MPa, about 80 MPa, about 90 MPa, or about 100 MPa. The blend of components may be pressed for a period of from about 2 minutes to about 30 minutes, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 25 minutes, or about 30 minutes. Step (iii) may comprise heating the blend for a time period of at least about 0.5 hours, about 1 hour, about 2 hours, about 3 hours, about 4 hours, or at least about 5 hours. Step (iii) may comprise heating the blend for a time period of from about 0.5 hours to about 5 hours, from about 0.5 hours to about 4 hours, from about 0.5 hours to about 3 hours, from about 0.5 hours to about 2 hours, or from about 0.5 hours to about 1 hour. Step (iii) may comprise heating the blend for a time period of no more than about 0.5 hours, about 1 hour, about 2 hours, about 3 hours, about 4 hours, or no more than about 5 hours. Step (iii) may comprise heating the blend for a time period of from about 2 to about 80 hours, from about 2 to about 60 hours, from about 2 to about 40 hours, from about 2 to about 20 hours, from about 2 to about 10 hours, or from about 2 to about 5 hours. Step (iii) may comprise heating the blend for a time period of from about 5 to about 80 hours, from about 5 to about 60 hours, from about 5 to about 40 hours, from about 5 to about 20 hours, or from about 5 to about 10 hours. Step (iii) may comprise heating the blend for a time period of from about 10 to about 80 hours, from about 10 to about 60 hours, from about 10 to about 40 hours, from about 10 to about 20 hours, or from about 10 to about 15 hours. Step (iii) may comprise heating the blend for a time period of from about 20 to about 80 hours, from about 20 to about 60 hours, from about 20 to about 40 hours, or from about 20 to about 25 hours. Step (iii) may comprise heating the blend for a time period of from about 30 to about 80 hours, from about 30 to about 60 hours, from about 30 to about 45 hours, or from about 30 to about 35 hours. Step (iii) may comprise heating the blend for a time period of from about 40 to about 80 hours, from about 40 to about 60 hours, from about 40 to about 50 hours, or from about 40 to about 45 hours. Step (iii) may comprise heating the blend for a time period of from about 50 to about 80 hours, from about 50 to about 60 hours, or from about 50 to about 55 hours. Step (iii) may comprise heating the blend for a time period of from about 60 to about 80 hours, from about 60 to about 70 hours, or from about 60 to about 65 hours. Step (iii) may comprise heating the blend for a time period of from about 70 to about 80 hours, or from about 70 to about 75 hours. Step (iii) may comprise heating the blend for a time period of at least about 2 hours, about 5 hours, about 10 hours, about 15 hours, about 20 hours, about 25 hours, about 30 hours, about 35 hours, about 40 hours, about 45 hours, about 50 hours, about 55 hours, about 60 hours, about 65 hours, about 70 hours, about 75 hours, or at least about 80 hours. Step (iii) may comprise heating the blend for a time period of no more than about 2 hours, about 5 hours, about 10 hours, about 15 hours, about 20 hours, about 25 hours, about 30 hours, about 35 hours, about 40 hours, about 45 hours, about 50 hours, about 55 hours, about 60 hours, about 65 hours, about 70 hours, about 75 hours, or no more than about 80 hours. Step (iii) may comprise heating the blend at a temperature of from about 150°C to about 400°C, from about 150°C to about 350°C, from about 150°C to about 300°C, from about 150°C to about 275°C, from about 150°C to about 250°C, from about 150°C to about 225°C, from about 150°C to about 200°C, or from about 150°C to about 175°C, from about 150°C. Step (iii) may comprise heating the blend at a temperature of at least about 200°C, about 225°C, about 250°C, about 275°C, about 300°C, about 325°C, about 350°C, about 375°C, or about 400°C. Step (iii) may comprise heating the blend at any of the aforementioned temperatures, up to about 450°C. Step (iii) may comprise heating the blend at a temperature of from about 350°C to about 400°C, from about 350°C to about 390°C, from about 350°C to about 380°C, from about 350°C to about 370°C, or from about 350°C to about 360°C. Step (iii) may comprise heating the blend at a temperature of from about 360°C to about 400°C, from about 360°C to about 390°C, from about 360°C to about 380°C, or from about 360°C to about 370°C. Step (iii) may comprise heating the blend at a temperature of from about 370°C to about 400°C, from about 370°C to about 390°C, or from about 370°C to about 380°C. Step (iii) may comprise heating the blend at a temperature of from about 380°C to about 400°C, or from about 380°C to about 390°C. Step (iii) may comprise heating the blend at a temperature of from about 390°C to about 400°C. Step (iii) may comprise heating the blend at a temperature of about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, or about 400°C. Step (iii) may comprise heating the blend at a temperature of at least about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, or at least about 400°C. Step (iii) may comprise heating the blend at a temperature of no more than about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, or no more than about 400°C. In step (iii), the blend may be heated in a program-controlled rotary sintering furnace. Step (ii) may be carried out simultaneously with step (iii). In this embodiment, the composition and plastic material of step (i) are blended while being heated, to form the composite. Blending the composition and plastic material of step (i) may be carried out using a blender, in particular, a high-speed multi-functional electric grain grinder, power: 900W, capacity: 150g. The blending of step (ii) may be carried out at from about 5000 rpm to about 25,000 rpm, for example about 5000 rpm, about 10,000 rpm, about 15,000 rpm, about 20,000 rpm, about 22,000 rpm, or about 25,000 rpm. Step (ii) may comprise blending the composition and plastic material of step (i) for at least about 0.5 minutes, about 1.0 minute, about 1.5 minutes, about 2.0 minutes, about 2.5 minutes, about 3.0 minutes, about 3.5 minutes, about 4.0 minutes, about 4.5 minutes, or at least about 5.0 minutes. Step (ii) may comprise blending the composition and plastic material of step (i) for no more than about 0.5 minutes, about 1.0 minute, about 1.5 minutes, about 2.0 minutes, about 2.5 minutes, about 3.0 minutes, about 3.5 minutes, about 4.0 minutes, about 4.5 minutes, or no more than about 5.0 minutes. Step (ii) may comprise blending the composition and plastic material of step (i) for about 0.5 minutes to about 5.0 minutes, for about 1.0 minutes to about 4.0 minutes, for about 1.0 minutes to about 3.0 minutes, or for about 1.0 minutes to about 2.0 minutes. According to a fourth aspect of the invention, there is provided a composite obtained by the process according to the third aspect. Advantageously, the composite according to the fourth aspect exhibits excellent resistance to extreme high temperatures and corrosive environments. Moreover, the composite according to the fourth aspect exhibits excellent wear resistance. Further, the composite according to the fourth aspect exhibits excellent dielectric properties. Moreover, the composite according to the fourth aspect exhibits preferable non-stick properties, therefore allowing articles which have been at least partially coated in the composite to be easily cleaned due to food adhesion to such articles being prevented. The composite may have a structure according to Compound 2: In some embodiments comprising Compound 2, n may be any integer from about 1 to about 10. For example, n may be selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. In some embodiments comprising Compound 2, n may be 1. In some embodiments comprising Compound 2, Ri may represent the residue of a dianhydride comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 2, R2 may represent the residue of a diamine comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 2, Ri may represent the residue of a dianhydride selected from the group consisting of pyromellitic dianhydride, 3,3',4,4'-Biphenyltetracarboxylic dianhydride, and 4,4'-Oxydiphthalic anhydride. In some embodiments comprising Compound 4, R2 may represent the residue of a diamine selected from the group consisting of p-Phenylenediamine, m- Phenylenediamine, 4,4'-Oxy dianiline, Diaminodiphenylmethane. 3,4'-Oxydianiline, and 4,d' In embodiments comprising Compound 2 and without wishing to be bound by theory, it is understood that a polyamic acid moiety, or moieties, present in the composition formed by combining an aromatic polyimide with an amino silane may undergo imidization to form a polyimide ring and releasing water as a byproduct. Advantageously, in embodiments where step (iii) comprises heating the blend at a temperature of at least about 250°C, in particular at least about 300°C, the imidization of the polyamic acid moiety, or moieties, reaches higher conversion rates, resulting in a denser structure. According to a fifth aspect of the invention, there is provided a use of the composite according to the fourth aspect as a seal, gasket, bearing, brake pad, bushing, cable, connector, surface material for cookware and food processing equipment. Beneficially, the composite according to the fourth aspect may be used as a seal, gasket or bearing which each require resistance to extreme temperatures and corrosive environments. Beneficially, the composite according to the fourth aspect may be used as a brake pad, bushing or seal which each are required to provide low friction and wear resistance. Beneficially, the composite according to the fourth aspect may be used in circuitry technology, for example in cables, connectors and circuit boards, due to its excellent dielectric properties. Beneficially, the composite according to the fourth aspect may be used as a surface layer on cookware and food processing equipment, ensuring easy cleaning due to food adhesion to such cookware and food processing equipment being prevented. According to a sixth aspect of the invention, there is provided an article formed using the composite according to the fourth aspect. According to a seventh aspect of the invention, there is provided a composition having a structure according to Compound 2. In some embodiments comprising Compound 2, Ri may represent the residue of a dianhydride comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 2, R2 may represent the residue of a diamine comprising any of the features, optional or otherwise, mentioned herein in relation to any aspect of the invention. In some embodiments comprising Compound 2, Ri may represent the residue of a dianhydride selected from the group consisting of pyromellitic dianhydride, 3,3',4,4'-Biphenyltetracarboxylic dianhydride, and 4,4'-Oxydiphthalic anhydride. In some embodiments comprising Compound 2, R2 may represent the residue of a diamine selected from the group consisting of p-Phenylenediamine, m-Phenylenediamine, 4,4'-Oxydianiline, 3,4'-Oxydianiline, and 4,4'-Diaminodiphenylmethane. The invention according to any of the first to seventh aspects may of course individually include any one or more of the features, optional or otherwise, of one another. Detailed Description of the Invention In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only. Example 1 3.0g of aromatic polyimide monomers of 3,3’,4,4’-Biphenyl tetracarboxylic diandhydride and m-Phenylenediamine is placed in a mixing device, for example a blender, for example, a high-speed multi-functional electric grain grinder, power: 900W, capacity: 150g. 100.0g of a filler material which, in the described embodiment, is mica, is also added to the mixing device. The mica is Sericite mica powder having a whiteness (WB) of 77.8, an average particle size of 14.8 pm, a 325 mesh sieve residue of 0.04% and a pH of 6.1. A solvent is also added to the mixing device. In the described embodiment, 15g of water is added to the mixing device. The dianhydride and diamine monomers, mica, and water are mixed in the mixing device for 10 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyl tetracarboxylic diandhydride; R2 represents the residue of Phenylenediamine. The composition may then be placed into a furnace to heat for 1 hour at 250°C. 30.0g of the composition is added to a mixing device, such as a blender, together with 70.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 25,000 rpm, and, in the described embodiment, at a speed of 22,000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 30 hours at 370°C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 2, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyl tetracarboxylic diandhydride; R2 represents the residue of Phenylenediamine. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 2 5.0g of aromatic polyimide monomers of 4,4'-Oxydiphthalic anhydride and 3,4-Oxydianiline are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is graphite, is also added to the mixing device. A solvent is also added to the mixing device. In the described embodiment, 20g of Ethanol is added to the mixing device. The aromatic polyimide, graphite and N-Methylpyrrolidone are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 4,4'-Oxydiphthalic anhydride; R2 represents the residue of 3,4-Oxy dianiline. The composition may then be placed into a furnace to heat for 1 hour at 250°C. 30.0g of the composition is added to a mixing device, such as a blender as described above, together with 70.0g of PTFE. The composition and the PTFE are blended together in a blender, as described in relation to Example 1, for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 22,000 rpm, and, in the described embodiment, at a speed of 22000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 10 hours at 3 80 °C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 2, wherein: Ri represents the residue of Oxy diphthalic anhydride; R2 represents the residue of 4,4-Oxydianiline. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 3 3.0g of aromatic polyimide monomers of pyromellitic dianhydride and 4,4-Oxydianiline are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is molybdenum disulfide, is also added to the mixing device. A solvent is also added to the mixing device. In the described embodiment, 10g of N-Methylpyrrolidone is added to the mixing device. The dianhydride and diamine monomers, molybdenum disulfide, and N-Methylpyrrolidone are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 3,3’,4,4-Biphenyltetracarboxylic dianhydride; R2 represents the residue of 4,4-Oxydianiline. The composition may then be placed into a furnace to heat for 3 hours at 200°C. 40.0g of the composition is added to a mixing device, such as a blender as described in relation to Example 1, together with 60.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 22,000 rpm, and, in the described embodiment, at a speed of 22000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 15 hours at 370°C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 2, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; R2 represents the residue of 4,4’-Oxydianiline. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 4 2.0g of aromatic polyimide monomers of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride and p-Phenylenediamine are placed in a mixing device, for example a blender such as that described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is carbon, is also added to the mixing device. A solvent is also added to the mixing device. In the described embodiment, 15g of N-Methylpyrrolidone is added to the mixing device. The aromatic polyimide, carbon, and N-Methylpyrrolidone are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 3,3’,4,4-Biphenyltetracarboxylic dianhydride; R2 represents the residue of p-Phenylenediamine. The composition may then be placed into a furnace to heat for 2 hours at 250°C. 45.0g of the composition is added to a mixing device, such as a blender as described in relation to Example 1, together with 55.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 22,000 rpm, and, in the described embodiment, at a speed of 22000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 30 hours at 370°C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 2, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; and R2 represents the residue of p-Phenylenediamine. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 5 0.5g of aromatic polyimide monomers of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride and p-Phenylenediamine are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is iron powder, is also added to the mixing device. A solvent is also added to the mixing device. In the described embodiment, 10g of N,N-dimethylacetamide is added to the mixing device. The dianhydride and diamine monomers, iron powder, and N,N-dimethylacetamide are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; R2 represents the residue of p-Phenylenediamine. The composition may then be placed into a furnace to heat for 2 hours at 200°C. 60.0g of the composition is added to a mixing device, such as a blender as described in relation to Example 1, together with 40.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 22,000 rpm, and, in the described embodiment, at a speed of 22000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 10 hours at 375°C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 4, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; R2 represents the residue of p-Phenylenediamine;. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 6 1.0g of aromatic polyimide monomers of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride and m-Phenylenediamine are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is ceramic powder, is also added to the mixing device. A solvent is also added to the mixing device. In the described embodiment, 10g of water is added to the mixing device. The dianhydride and diamine monomers, ceramic powder, and N-Methylpyrrolidone are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; R2 represents the residue of m-Phenylenediamine;. The composition may then be placed into a furnace to heat for 1 hour at 300°C. 45.0g of the composition is added to a mixing device, such as a blender as described in relation to Example 1, together with 55.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 22,000 rpm, and, in the described embodiment, at a speed of 22000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 10 hours at 380 °C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 4, wherein: Ri represents the residue of 3,3’,4,4’-Biphenyltetracarboxylic dianhydride; and R2 represents the residue of m-Phenylenediamine. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 7 - Example of a mica / epoxy composite 3.0g of aromatic polyimide monomers of pyromellitic dianhydride and 4,4-Oxydianiline are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is mica, is also added to the mixing device. The dianhydride and diamine monomers, and mica are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of pyromellitic dianhydride; R2 represents the residue of 4,4-Oxydianiline. The composition may then be placed into a furnace to heat for 3 hours at 200°C. 40.0g of the composition is added to 60.0g of Epoxy. The Epoxy resin is IN2 Epoxy Infusion Resin, which is a mix of bis-[4-(2,3-epoxipropoxi)phenyl]propane, Phenolic epoxy resin F-44, l,6-bis(2,3-epoxypropoxy)hexane, and propylene carbonate. The composition and the Epoxy are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, to form a blend. The blend is vacuumed for 30min to remove air, and then placed at an ambient temperature for 24h to form a composite of the composition and Epoxy. The composite provides for each of the advantages as outlined above. Example 8 - Example of Bronze / copper PTFE composite 1.0g of aromatic polyimide monomers of pyromellitic dianhydride and 4,4-Oxydianiline are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is Bronze or copper, is also added to the mixing device. The dianhydride and diamine monomers, and Bronze are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of pyromellitic dianhydride; R2 represents the residue of 4,4-Oxydianiline. The composition may then be placed into a furnace to heat for 3 hours at 160°C. 70.0g of the composition is added to a mixing device, such as a blender as described in relation to Example 1, together with 30.0g of PTFE. The composition and the PTFE are blended together for between 2 and 10 minutes, and, in the described embodiment, for 5 minutes, at a speed of between about 500 and about 25,000 rpm, and, in the described embodiment, at a speed of 25000 rpm, to form a blend. The blend is then pressed, and then placed in a furnace to sinter for 6 hours at 370°C to form a composite of the composition and PTFE. The furnace is a program-controlled rotary sintering furnace. The composite may have a structure according to Compound 2, wherein: Ri represents the residue of pyromellitic dianhydride; R2 represents the residue of 4,4-Oxydianiline. The composite provides for each of the advantages as outlined above. The composite may then be used to form an article such as a seal. Example 9 - Example of PTFE micropowder / epoxy composite 1.0g of aromatic polyimide monomers of pyromellitic dianhydride and 4,4-Oxydianiline are placed in a mixing device, for example a blender as described in relation to Example 1. 100.0g of a filler which, in the described embodiment, is PTFE, is also added to the mixing device. The dianhydride and diamine monomers, and PTFE are mixed in the mixing device for 2-5 minutes. This forms a composition having a structure according to Compound 1, wherein: Ri represents the residue of pyromellitic dianhydride; R2 represents the residue of 4,4-Oxydianiline. The composition may then be placed into a furnace to heat for 1 hours at 160°C. 10.0g of the composition is added to 90.0g of Epoxy resin. In this example, the 5 Epoxy resin is IN2 Epoxy Infusion Resin, which is a mix of bis-[4-(2,3-epoxipropoxi)phenyl]propane, Phenolic epoxy resin F-44, l,6-bis(2,3- epoxypropoxy)hexane, and propylene carbonate. The composition and the Epoxy resin are mixed together for between 2 and 10 minutes, and, in the described example, for 5 minutes, to form a blend. The blend is 10 vacuumed for 30min to remove air, and then placed at an ambient temperature for 24h to form a composite of the composition and Epoxy. The composition provides for each of the advantages as outlined above. The composition may then be used as low friction material. The one or more embodiments are described above by way of example only. 15 Many variations are possible without departing from the scope of protection afforded by the appended claims.

Claims

1. A process for preparing a composition, the process comprising the steps:a. Adding a dianhydride and diamine monomer of an aromatic polyimide to a filler,b. In situ mixing the components of step (a) to form the composition.

2. A process according to claim 1, preferably wherein the filler is present in an amount of from about 70.0 to about 99.9 wt.%, based on the total weight of the components reacted in step (a), for example from 70.0 to about 99.8 wt.%, from about 70.0 to about 99.7 wt.%, from 70.0 to about 99.6 wt.%, from 70.0 to about 99.5 wt.%, based on the total weight of the components reacted in step (a).

3. A process according to claim 1, wherein the filler is selected from the group consisting of a carbonate, a silicate, a carbon, a metallic, and a polymeric filler (such as PTFE), or combinations thereof.

4. A process according to any preceding claim, wherein the aromatic polyimide is formed by reacting a dianhydride with a diamine, optionally wherein the dianhydride is an organic acid dianhydride, for example a carboxylic dianhydride.

5. A process according to claim 4, wherein the dianhydride and / or the diamine is a cyclic compound comprising one, two, three, four, five, or more than five, rings.

6. A process according to any of claims 4 or 5, wherein the dianhydride and / or the diamine comprises at least one aromatic ring, for example one, two, three, four, or more than four, aromatic rings.

7. A process according to any of claims 4 to 6, wherein the dianhydride and / or the diamine comprises at least one heterocyclic ring, for example one, two, three, four, or more than four, heterocyclic rings, optionally wherein the at least one heterocyclic ring comprises at least one aromatic heterocyclic ring and / or at least one non-aromatic heterocyclic ring.

8. A process according to any of claims 4 to 7, wherein the dianhydride and / or the diamine comprises a biphenyl group, and / or wherein the dianhydride comprises a phenyl group bonded to at least one moiety comprising an anhydride group.

9. A process according to any of claims 4 to 8, wherein the diamine comprises at least one functional group selected from the group consisting of diphenyl ether, diphenyl sulphide, and diphenyl alkane, optionally wherein the diphenyl alkane is selected from the group consisting of diphenylmethane, 1,1-Diphenylethane, 1,2-Diphenylethane, and 1,3-Diphenylpropane.

10. A process according to any of claims 4 to 9, wherein the dianhydride is selected from the group consisting of pyromellitic dianhydride, 3,3',4,4'-Biphenyltetracarboxylic dianhydride, and 4,4'-Oxydiphthalic anhydride, and / or wherein the diamine is selected from the group consisting of p-Phenylenediamine, m-Phenylenediamine, 4,4'-Oxydianiline, 3,4'-Oxydianiline, and 4,4'-Diaminodiphenylmethane.

11. A process according to any preceding claim, wherein the composition is a polyimide according to compound 1:l j nwherein:Ri represents the residue of a dianhydride formed from a dianhydride asdefined by any of claims 4 to 8 or 10;R2 represents the residue of a diamine formed from a diamine as definedby any of claims 5 to 10; and12. A process according to any preceding claim, wherein the dianhydride and diamine monomer of an aromatic polyimide is present in an amount of fromabout 0.5 to about 10.0 wt.%, based on the total weight of the components reacted in step (a).

13. A process according to any preceding claim, wherein step (a) further comprises adding a solvent, optionally wherein the solvent is a solvent selected from the group consisting of N-Methylpyrrolidone, N,N-Dimethylformamide, N,N-dimethylacetamide, Dimethyl Sulfoxide, Chloroform, Tetrahydrofuran, Ethanol, and water, optionally wherein the solvent is present in an amount of from about 5.0 to about 25.0 wt.%, based on the total weight of the components reacted in step (a).

14. A process according to any preceding claim, wherein step (b) includes mixing the components of step (a) for from about 1 minute to about 30 minutes, and / or wherein the process comprises, after step (b), step (c), heating the mixed components of step (a) at a temperature of from about 50°C to about 350°C, wherein step (c) the solvent is recycled15. A composition obtained by the process according to any preceding claim, wherein the composition has structure according to compound 2:wherein:Ri represents the residue of a dianhydride formed from a dianhydride as defined by any of claims 4 to 8 or 10;R2 represents the residue of a diamine formed from a diamine as defined by any of claims 5 to 10; and16. A process for preparing a composite, the process comprising the steps:i. Providing a composition formed by combining an aromatic polyimide with an filler; and combining the composition with a plastic material,ii. Blending the composition and plastic material of step (i) to form a blend, iii. Heating the blend to form the composite.

17. A process according to claim 16, wherein the composition is the composition formed by the process according to any of claims 1 to 14.

18. A process according to claim 16 or 17, wherein the plastic material is a thermoplastic polymer, optionally wherein the polymer is any matrix with which inorganic particulate solids are employed and include plastics, resins and rubber materials, selected from the group consisting of polytetrafluoroethylene, polyetheretherketone, polyolefins such as polyethylene and polypropylene, polyvinyl chloride, natural rubber, synthetic rubbers such as silicon rubber, styrene-butadiene rubber, ethylene-propylene terpolymer rubber and urethane rubber, phenolic resins, and epoxy resins.

19. A process according to any of claims 16 to 18, wherein the composition of step (i) is present in an amount of from about 10.0 to about 50.0 wt.%, based on the total weight of the composition and the plastic material reacted in step (i), and / or wherein the plastics material is present in an amount of from about 40.0 to about 80 wt.%, based on the total weight of the composition and the plastic material reacted in step (i).

20. A process according to any of claims 16 to 19, wherein step (iii) comprises heating the blend for a time period of from about 2 to about 80 hours, optionally wherein step (iii) comprises heating the blend at a temperature of from about 150°C to about 400°C.

21. A composite obtained by the process according to any of claims 16 to 20.

22. A composite according to claim 21, wherein the composite has a structureaccording to Compound 2:wherein:Ri represents the residue of a dianhydride formed from a dianhydride as defined by any of claims 4 to 8 or 10;R2 represents the residue of a diamine formed from a diamine as defined by any of claims 5 to 10; and23. Use of the composite according to claim 22 as a seal, gasket, bearing, brake pad, bushing, cable, connector, or surface material for cookware and food processing5 equipment.

24. An article formed using the composite according to claim 22.

25. A composition having a structure according to Compound 2, wherein:Ri represents the residue of a dianhydride selected from the group10 consisting of pyromellitic dianhydride, 3,3',4,4'-Biphenyltetracarboxylic dianhydride, and 4,4'-Oxydiphthalic anhydride;R2 represents the residue of a diamine selected from the group consisting of p-Phenylenediamine, m-Phenylenediamine, 4,4'-Oxydianiline, 3,4'-15 Oxydianiline, and 4,4'-Diaminodiphenylmethane.