WO2008133672A2

WO2008133672A2 - Nanowires and coatings of self-assembled nanoparticles

Info

Publication number: WO2008133672A2
Application number: PCT/US2007/026195
Authority: WO
Inventors: Mickael Havel; Yury Gogotsi; Kris Behler
Original assignee: Drexel University; Mattia, Davide
Priority date: 2006-12-22
Filing date: 2007-12-21
Publication date: 2008-11-06
Also published as: WO2008133672A3

Abstract

Disclosed are composite materials comprising a nanofiber having a cross-sectional dimension in the range of from 1 nm to about 10,000 nm, and an outer surface, and a plurality of nanoparticles grafted to the outer surface of the fiber via a polyelectrolyte. Also disclosed are methods for manufacturing such composite materials. Further disclosed are methods and apparatuses for forming patterns of nanoparticle-coated nano fibers on substrates.

Description

NANOWIRES AND COATINGS OF SELF-ASSEMBLED NANOPARTICLES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 60/871,506 filed December 22, 2006, the entirety of which is incorporated by reference herein.

FIELD OF THE INVENTION

[0002] The disclosed invention pertains to the field of nanoparticles. The disclosed invention also pertains to the field of surface coatings, especially for fibers.

BACKGROUND OF THE INVENTION

[0003] Various scientific and patent publications are referred to herein. Each is incorporated by reference in its entirety.

[0004] Nanotubes and other nanoparticles possess unique physical properties that make them suitable for use in a wide range of applications including materials science, sensor technology, electron emitters, electromagnetic shields, and bio technology. Accordingly, it is desirable to modify or enhance materials used in these applications with a coating of multi- walled nanotubes ("MWNTs"; MWNTs include nanotubes having two or more walls) to use the MWNTs' unique physical properties to enhance the materials' performance; coatings of other nanoparticles may also be desirable. -> ^'""-

[0005] Much effort has been expended in synthesizing various nanoparticle containing materials. Both single-walled nanotubes ("SWNTs") and MWNTs, however, do not disperse easily in solvents and polymer solutions due to their strong tendency to form bundles and aggregates. As a result, composite materials loaded with carbon nanotubes show little or no improvement in their mechanical properties.

[0006] While many efforts have been dedicated to improving the dispersion of the nanotubes by using surfactants, or functionalization of the nanotubes' outer walls, control over the nanotubes' distribution remains a challenge because MWNTs aggregate easily and this tendency to aggregate is known to persist even after the MWNTs are chemically modified. Because of MWNTs' tendency to aggregate, materials that incorporate MWNT dispersions often show little to no improvement in their physical properties. Accordingly, there is a need for a method by which nanotubes or other nanoparticles may be uniformly dispersed and then integrated into composite materials so as to take full advantage of the nanotubes' or nanoparticles' unique physical properties.

[0007] Chemical vapor deposition ("CVD") is one method presently used to create nanotube, nanodiamond, and other carbon coatings on material surfaces. CVD, however, is a slow, high-temperature process that cannot be applied to coat heat-sensitive materials. Thus, there is a need for a method by which to apply a uniform, high-density coating of MWNTs to a surface so as to take full advantage of the MWNTs' unique physical properties without the process operating at high temperatures.

[0008] In addition, carbon nanotube-based field emission displays ("FEDs") are currently under development. These displays are based on using a coating of carbon nanotubes as a source of electrons emission. The difficulty with this approach, however, is that the high density of carbon nanotube coatings presently achievable creates short-outs, which in turn prevent efficient emission. Hence, there is a need for a method by which carbon nanotubes could be placed on a substrate at a controlled coating density or in a controlled pattern for use in FED applications.

SUMMARY OF THE INVENTION

[0009] In overcoming the challenges inherent in creating materials capable of utilizing the unique properties of nanoparticles in creating an alternative to massive incorporation of nanoparticles into bulk polymers, and of creating a method for attaching nanoparticles to materials that cannot tolerate extreme processing conditions, the present invention provides, inter alia, a method of disposing a nanoparticulate coating on a polymeric material, comprising contacting at least one polymeric material comprising a plurality of surface functional groups with a polyelectrolyte to give rise to at least one polyelectrolyte-linked polymeric material; and contacting the at least one polyelectrolyte-linked polymeric material with at least one functionalized nanoparticle, to give rise to a coating of one or more nanoparticles disposed on the at least one polymeric material.

[0010] In another aspect, the present invention provides a polymer composite, comprising a polymer; and at least one nanoparticle characterized as bound to the polymer by at least one electrolyte

[0011] The general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as defined in the appended claims. Other aspects of the present invention will be apparent to those skilled in the art in view of the detailed description of the invention as provided herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The summary, as well as the following detailed description, is further understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings exemplary embodiments of the invention; however, the invention is not limited to the specific methods, compositions, and devices disclosed. In addition, the drawings are not necessarily drawn to scale. In the drawings:

[0013] FIG. 1 illustrates one exemplary, non-limiting principle of the MWNT self- assembly on polyacrylonitrile ("PAN") fibers; after functionalization, both PAN and MWNTs become negatively charged; poly(diallyldimethylammonium chloride) ("PDDAC"), a positively charged polyelectrolyte, is used to attach MWNTs (black layer) on the surface of PAN nanofibers;

[0014] FIG. 2 depicts photographs of vials showing HNO₃-oxidized MWNTs in water (A) and the same vial after immersion of a white PDDAC-coated PAN nanofiber mat (B);

[0015] FIG. 3 depicts SEM (top) and TEM (bottom) images of MWNT-coated PAN nanofibers produced by two layer-by-layer deposition ("LLD") cycles; note the high density and uniformity of MWNT adsorbed onto the fibers;

[0016] FIG. 4 depicts an exemplary apparatus for electrospinning nanofibers onto a substrate mounted onto a rotating cylinder; and,

[0017] FIG. 5 depicts a schematic illustrating the use of a pattern of electrodes to create a controllably-patterned deposition of nano tube-coated nanofibers.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0018] The present invention may be understood more readily by reference to the following detailed description taken in connection with the accompanying figures and examples, which form a part of this disclosure. It is to be understood that this invention is not limited to the specific devices, methods, applications, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention. Also, 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. The term "plurality", as used herein, means more than one. When a range of values is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. All ranges are inclusive and combinable. [0019] It is to be appreciated that certain features of the invention which are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. Further, reference to values stated in ranges include each and every value within that range.

[0020] The present invention provides methods of disposing a nanoparticulate coating on a polymeric material. The methods include contacting at least one polymeric material comprising a plurality of surface functional groups with a polyelectrolyte to give rise to at least one polyelectrolyte-linked polymeric material, and contacting the at least one polyelectrolyte- linked polymeric material with at least one functionalized nanoparticle, so as to give rise to a coating of one or more nanoparticles disposed on the at least one polymeric material.

[0021] Suitable polymeric materials include polymer films, layers, membranes, ropes, fibers, and strands. The polymer may also include a metal, a glass, a ceramic, or both, and may be reinforced by additional materials.

[0022] Polymeric nanofibers are considered especially suitable. Suitable nanofibers can have cross-sectional dimensions in the range of from about 1 nm to about 10,000 nm, or in the range of from about 5 nm to about 500 nm, or in the range of from about 10 nm to about 300 nm. Nanofibers may have a non-circular cross-sectional area, or, alternatively, may have a cross-sectional area of the nanofiber characterized as being a polygon having from 2 to 12 sides. The nanofiber may be either a solid core fiber or a hollow core fiber; hollow core nanofibers suitably have core diameters in the range of from about 1 nm to about 5,000 nm.

[0023] Polymeic materials suitable for the disclosed methods include one or more surface functional groups, which groups are, in some embodiments, negatively charged. Preferred functional groups include COO-, -NO3,— SO3-, -O-, or any combination thereof; a polymer comprising COO- functional groups is depicted in FIG. 1. Surface functional groups may, in other embodiments, be positively charged.

[0024] The plurality of surface functional groups of the polymeric material may be provided by contacting the at least one polymeric material with a base. Suitable bases have a pH equal to or greater than about 9, or equal to or greater than about 11, or an even higher pH value. NaOH, KOH, NH₄OH, Ca(OH)₂, or any combination thereof, are all considered bases suitable in the claimed invention. Contacting a polymeric material with a base to give rise to carboxylic acid groups on the surface of the polymeric material is considered a suitable manner, see FIG. 1, of forming surface groups on the polymeric material. [0025] Electrolytes suitable for use in the present invention include positively charged polyelectrolytes, and, in other embodiments, negatively charged electrolytes. The electrolyte is suitably a polyelectrolyte that is capable of bonding to the polymeric material. In some embodiments, the polyelectrolyte include one or more positive charges that bond to one or more of the surface functional groups on the polymeric material. The polyelectrolyte may be include tetracoordinated nitrogen compound or copolymers thereof, and can include one or more tetraalyklammonium groups A copolymer is suitably a random copolymer, an alternating copolymer, a graft copolymer, a block copolymer, a multiblock copolymer, a star copolymer, a dendrimer, or any combination thereof. Poly(diallyldimethylammonium) chloride is considered an especially suitable polyelectrolyte, as shown in FIG. 1.

[0026] Nanoparticles suitable for use in the claimed methods include a single-wall carbon nanotube, a multiwall carbon nanotube, a quantum dot nanocrystal, a polymeric nanoparticle, a nanodiamond, a metal nanoparticle or any combination thereof. Nanowires are also considered suitable nanoparticles for the claimed invention.

[0027] Suitable nanoparticles also comprise one or more surface functional group, which include an amorphous carbon, a graphene, an amine, an amide, a carbonyl, a carboxyl, an alcohol, an aldehyde, a thiol, a sulfoxide, or any combination thereof. Other suitable surface functional groups will be dictated by the needs of the user and will be apparent to those having ordinary skill in the art. Nanoparticles are available from sources known to those having ordinary skill in the art, which sources include Hyperion Catalysis, Inc. (Cambridge, MA, USA) (www.fibrils.com), Showa Denko (Japan) (www.sdk.co.jp/html/english/), and Arkema (Europe/USA) (www.arkema.com). Other nanoparticles are available from Nanoblox, Inc., Boca Raton, FL, USA (www.nanobloxinc.com) (nanodiamonds); Evident Technologies, Troy, NY, USA (www.evidenttech.com) (quantum dots); and Arkema, Europe (www.arkema.com) (nanoparticles).

[0028] Functionalized nanoparticles may include positive or negative charges; negatively-charged nanoparticles are considered particularly suitable. Functionalized nanoparticles are provided, in some configurations, by contacting the nanoparticles with an oxidizing agent. Acids are considered suitable oxidizing agents, including acids with pH values of less than about 6, or less than about 4, or having an even lower pH value. Acids can include nitric acid, sulfuric acid, perchloric acid, dichromic acid, or any combination thereof. Other suitable oxidizing agents include O₂, O₃, CO₂, CrO₃, MnO₂, KMnO₄, K₂Cr2O₇, or any combination thereof. [0029] The functionalized nanoparticles are suitably dispersed in a fluid, which dispersion is preferably uniform. The fluid may be aqueous, and may also include one or more solvents, such as dimethyl formamide. Dispersion may be aided by mixing, agitating, sonicating, and by other like methods. It has been observed that nanotubes oxidized with nitric acid disperse essentially uniformly in water, as shown in FIG. 2.

[0030] Contacting the polymer with the nanoparticles is accomplished by mixing, agitating, blending, spraying, pouring, and the like. Excess nanoparticles may be removed by washing, decanting, or even by sonicating.

[0031] In some embodiments, at least a portion of the polyelectrolyte-linked polymer is removed following the bonding of the nanoparticles. This removal leaves behind a free-standing portion of the nanoparticle coating that conforms to the shape of the removed polymer, which coating may be continuous or partly continuous. The removal is accomplished by heating, selective dissolution, selective etching, or any combination thereof. As a non-limiting example, a polymer fiber may be dissolved by a solvent that selectively dissolves the polymer without adversely affecting the nanoparticle coating. The left-behind nanoparticle coating can characterized as being sin the form or a pipe, a sheet, a bent sheet, a partially rolled sheet, a manifold, or any combination thereof, all of which depend on the shape of the removed polymer. Such free-standing nanoparticle coating may be used as a conductor, a structural reinforcement, a filter, a membrane, and in other applications that will be apparent to those having ordinary skill in the art.

[0032] In some embodiments, a quantity of polymer is deposited on a substrate before the nanoparticles are grafted onto the polymer. Such deposition may be accomplished by electrospinning a quantity of polymer - which polymers are described elsewhere herein - comprising at least one surface functional group onto a substrate and then grafting, with an electrolyte, at least one nanoparticle onto the quantity of polymer. Alternatively, polymer may be spin coated, cast, sprayed, painted, dripped, or otherwise deposited onto the substrate. Polymers suitable for such embodiments will depend on the needs and constraints of the user, but are chosen so as to be suitable for electrospinning. Polymers including at least one acrylonitrile group are considered especially suitable.

[0033] In other embodiments, the quantity of polymer electrospun or otherwise deposited onto the substrate is characterized is a nanofiber. The dimensions of suitable nano fibers are described elsewhere herein. The dimensions of a particular nanofiber may be controlled, at least in part, by the needs of the user or by limitations of an apparatus used to perform the claimed method. [0034] Substrates suitable for the claimed method include glass, ceramics, coated metals, polymers, and the like. The electospinning can be performed by dispensing polymer solution from a charged delivery device onto the substrate having an opposite charge. In certain embodiments, the substrate may be neutral in charge or uncharged. Depending on the user's needs, specific portions of the substrate are suitably patterned so as to enable the electrospinning or other deposition of polymer to a discrete, defined area of the substrate.

[0035] One such embodiment is depicted in FIG. 4. hi that figure, the substrate (400) comprises a discrete area of charge (430) that is opposite in charge to the charge on the delivery device (410). As shown in FIG. 4, a stream of suitable polymer (440) is dispensed from the charged delivery device (410) and is attracted the charged portion of the substrate (430). FIG. 4 also depicts the completed deposition of polymer onto a cross-shaped target (420) having a charge opposite to that of the charged delivery device.

[0036] Depending on the embodiment of the invention, either the substrate, the dispensing device, or both can be moved during the electrospinning. One such embodiment is shown in FIG. 5, in which a rotating roller (500) bears a charge opposite to the charge carried by the polymer delivery device (510). As depicted in that figure, the delivery device (510) dispenses polymer (520) while moving laterally along the axis of the roller, which dispensing results in a strip of polymer (530) being formed around the circumference of the roller as the roller rotates during polymer dispensation.

[0037] Electrospinning can also include placing one or more moveable electrical grounds behind the substrate relative to the electrically charged delivery device. In some embodiments, movement of the grounds during polymer dispensing effects deposition of the polymer to a particular location or locations on the substrate.

[0038] Grafting nanoparticles to the polymer includes the step of charging the surface functional groups of the polymer, which charge is preferably negative. Suitable functional groups include COO^", -NO3, ^~SO3^~, -O^~, or any combination thereof, and other suitable charged groups will be known to those having ordinary skill in the art.

[0039] Such charged groups may be effected through contacting the polymer with a base. Suitable bases are described elsewhere herein, and preferably give rise to at least one carboxylic acid group on the surface of the polymer.

[0040] The grafting also includes contacting one or more polymers with a polyelectrolyte. Suitable contacting and polyelectrolytes are described elsewhere herein. Grafting further includes contacting at least one polymer with at least one functionalized nanoparticle, as described elsewhere herein. [0041] Following the grafting of one or more nanoparticles, a portion of the polymer, substrate, or both, may be removed to give rise to a free-standing assembly of nanoparticles. The polymer, substrate, or both, can be removed by methods described elsewhere herein. The invention also includes compositions made according to the claimed methods.

[0042] The present invention also includes compositions made according to the claimed methods.

[0043] The claimed invention also provides polymeric composites. The composites include a polymer and at least one nanoparticle bound to the polymer by at least one polyelectrolyte.

[0044] Suitable electrolytes are described elsewhere herein; poly(diallyldimethylammonium) chloride is considered especially suitable.

[0045] Nanoparticles include a nanotube, a multiwall carbon nanotube, a quantum dot nanocrystal, a polymeric nanoparticle, a nanodiamond, a metallic nanoparticle, or any combination thereof.

[0046] Nanotubes are considered especially suitable. Single wall carbon nanotubes having a diameter in the range of from about 0.4 to about 5 nm, or in the range of from 0.8 to about 4 nm, or in the range of from about 1 to about 5 nm, are all considered suitable. Single wall carbon nanotubes having a length in the range of from about 1 to about 100 microns, or a length in the range of from about 20 to about 80 microns, are all considered suitable.

[0047] Multiwall carbon nanotubes having a diameter in the range of from about 0.5 to about 300 nm, or in the range of from 30 to about 70 nm, or in the range of from about 40 to about 60 nm, are considered suitable. The multiwall carbon nanotubes can also have a length in the range of from about 1 um to about 100 um, or from about 20 urn about 80 um.

[0048] In some embodiments, the polymeric composite includes at least one metal, at least one glass, at least one ceramic, or any combination thereof. Polymers having at least one acrylonitrile repeat group and acrylonitrile copolymers are considered suitable polymeric materials, including polyacrylonitrile. Other suitable polymeric materials will be apparent to those having ordinary skill in the art.

[0049] Polymeric materials characterized as nanofibers are considered especially suitable. Such nanofibers have a cross-sectional dimension in the range of from about 1 nm to about 10,000 nm, or in the range of from about 5 nm to about 5000 nm, or in the range of from about 7 nm to about 2500 nm, or even in the range of from about 10 nm to about 300 nm. Nanofibers can have circular cross-sectional areas, or non-circular cross-sectional areas, which can be polygonal and have from 2 to 12 sides. Nanofibers can also be solid core or hollow core nanofibres; suitable hollow core nanofibers are described elsewhere herein. A nanofiber may include a core of one material, which core may be at least partially surrounded by another material.

EXAMPLES

Example 1

[0050] MWNTs were electrostatically grafted onto functionalized electrospun PAN nanofibers. The resulting material consists of nanowires (approximately 200 nm in diameter), displaying a highly dense and uniform coating of MWNTs.

[0051] To obtain these nanowires, PAN nanofiber mats were immersed into a sodium hydroxide solution to functionalize the fibers' surface with COOH groups. The fibers were then immersed into a PDDAC solution and afterwards into a suspension of oxidized MWNT (oxidized in HNO₃ to create COOH groups). No desorption has been observed after 1 hour of sonication in water or after 4 days of stirring in N,N dimethylformamide ("DMF"). This lack of desorption suggests strong binding between the MWNT and the fibers. Any negatively charged surface (e.g. COOH-grafted) can be coated by this method, including single fibers, flat wafers or any other complex surface.

[0052] MWNTs were provided by Arkema (France). PDDAC (20 wt% in water, Mw = 100,000-200,000 g/mol) was purchased from Sigma- Aldrich. Nitric acid (37.5%), sodium hydroxide and sodium chloride were purchased from Fisher Scientific. 10 mg of MWNT were immersed in 50 mL of nitric acid (37.5%) and stirred at 110°C under reflux for 48 hrs. The nanotubes were then washed until neutral pH was reached and dispersed in 100 mL of deionized (DI) water. The resulting solution was translucide black and stable over time (remaining black over 2 months with little sedimentation), showing efficient repulsion between the MWNTs due to COOH groups functionalization on the tubes surface.

[0053] For the electrospinning of PAN nanofibers, a solution of 6 wt% of PAN in DMF was prepared. The electrospinning was performed under ambient conditions with an electric field of lkV/cm, as described in Ko, F.; et al, Adv. Mater., 2003; 15, 1161 et. seq. The fiber mats were then immersed in IN NaOH at 80°C for 20 min, following the protocol developed by Drew, C; et al., Polymeric Nanofibers, 2006, 10: 137-148. The mat turned from white to yellow/orange, indicating the oxidation of fibers (COOH functionalization).

[0054] The functionalized PAN nanofibers were then immersed for 30 min in an aqueous solution containing 10 niM of PDDAC (regarding the monomer) and 100 niM of NaCl. After being thoroughly washed in DI water, the mats were immersed for 30min into the solution of oxidized MWNTs. When performed in cycles, this procedure can be used to form thick self- assembly layers of MWNTs; a representative schematic is shown in FIG. 1.

[0055] The resulting nanofiber mats were investigated by field emission scanning electron microscopy (FESEM, Supra 50/VP from Zeiss) and transmission electron microscopy (TEM, 2010F from JEOL).

Example 2

[0056] FIG. 2 shows 20ml vials containing oxidized MWNTs (48 h in HNO₃ at HO⁰C) before and after immersion of the PDDAC-coated nanofiber mats. The vial on the left (FIG. 2A) shows that the oxidation treatment is efficient in improving the MWNTs' solubility, giving a stable black nanotube solution. However, after 30 min of immersion of the PDDAC-coated mats, the solution turns as clear as water and the mats turn from white to dark grey (FIG. 2B). After a second layer deposition, the mats become black. This proves the efficient grafting of MWNTs onto the nanofϊbers. To further investigate the self-assembly process, SEM and TEM studies were performed on PAN nanofibers after two cycles. The results are shown in FIG 3.

[0057] From FIG. 3, it is seen that the density of MWNTs is high with a uniform coverage. The strength of the interaction between the MWNTs and the PAN nanofibers can be inferred by observing that after sonication in DI water for 1 hr or mechanical stirring in DMF (50°C) for 4 days, the mats remain completely black and the solution completely transparent. Without being bound to any particular theory of operation, it is believed that this suggests strong bonding between the MWNTs and the nanofibers.

Example 3

[0058] In addition, the claimed methods have been successfully applied to comparatively larger carbon fibers —silicon carbide (SiC) fibers 150 μm in diameter - and to planar surfaces to show their feasibility. The density of nano tubes on the surface of nanofibers is significantly higher than that sufficient to achieve percolation and high electrical conductivity.

Claims

What is Claimed:

1. A method of disposing a nanoparticulate coating on a polymeric material, comprising:

contacting at least one polymeric material comprising a plurality of surface functional groups with a polyelectrolyte to give rise to at least one polyelectrolyte-linked polymeric material; and

contacting the at least one polyelectrolyte-linked polymeric material with at least one functionalized nanoparticle, to give rise to a coating of one or more nanoparticles disposed on the at least one polymeric material.

2. The method of claim 1, wherein the polymeric material is characterized as being a nanofiber.

3. The method of claim 1, wherein the nanofiber comprises a cross-sectional dimension in the range of from about 1 nm to about 10,000 nm

4. The method of claim 1, wherein the nanofiber comprises cross-sectional dimension in the range of from about 10 nm to about 500 nm.

5. The method of claim 1, wherein the polymeric material is characterized as being a film.

6. The method of claim 1, wherein the surface functional groups of the polymeric material are negatively charged.

7. The method of claim 6, wherein the surface functional groups of the polymeric material are positively charged.

8. The method of claim 6, wherein one or more surface functional groups comprise -COO^", -NO₃,^"-SO₃\ -O^~, ' or any combination thereof.

9. The method of claim 1, wherein the polyelectrolyte comprises a positively charged polyelectrolyte.

10. The method of claim 1, wherein the polyelectrolyte comprises a negatively charged polyelectrolyte.

11. The method of claim 1 , wherein the polyelectrolyte is capable of bonding to the polymeric material.

12. The method of claim 11 , wherein the polyelectrolyte comprises positive charges that bond to one or more of the surface functional groups on the polymeric material.

13. The method of claim 11, wherein the polyelectrolyte comprises a tetracoordinated nitrogen compound, or any copolymer thereof.

14. The method of claim 13, wherein the tetracoordinated nitrogen compound comprises a tetraalyklammonium group.

15. The method of claim 13, wherein the tetracoordinated nitrogen compound comprises poly(diallyldimethylammonium) chloride.

16. The method of claim 13, wherein the copolymer includes a random copolymer, an alternating copolymer, a graft copolymer, a block copolymer, a multiblock copolymer, a star copolymer, a dendrimer, or any combination thereof.

17. The method of claim 1, wherein the plurality of surface functional groups are provided by contacting the at least one polymeric material with a base.

18. The method of claim 17, wherein the base has a pH equal to or greater than about 9.

19. The method of claim 17, wherein the base comprises an aqueous solution of NaOH, KOH, NH₄OH, Ca(OH)₂, or any combination thereof.

20. The method of claim 17, wherein contacting the polymeric material with a base gives rise to carboxylic acid groups on the surface of the polymeric material.

21. The method of claim 1, wherein the functionalized nanoparticle comprises a negative charge.

22. The method of claim 21, wherein the functionalized nanoparticle is oxidized.

23. The method of claim 1, wherein the functionalized nanoparticle comprises a positive charge.

24. The method of claim 1, wherein at least one nanoparticle comprises a single-wall carbon nanotube, a multiwall carbon nanotube, a quantum dot nanocrystal, a polymeric nanoparticle, a nanodiamond, a metal nanoparticle or any combination thereof.

25. The method of claim 24, wherein a nanoparticle further comprises a surface functional group.

26. The method of claim 25, wherein the surface functional group comprises an amorphous carbon, a graphene, an amine, an amide, a carbonyl, a carboxyl, an alcohol, an aldehyde, a thiol, a sulfoxide, or any combination thereof.

27. The method of claim 24, wherein the oxidized nanoparticles are provided by contacting the nanoparticles with at least one oxidizing agent.

28. The method of claim 27, wherein the oxidizing agent comprises an acid.

29. The method of claim 28, wherein the acid has a pH less than about 6.

30. The method of claim 28, wherein the acid has a pH less than about 4.

31. The method of claim 28, wherein the acid includes nitric acid, sulfuric acid, perchloric acid, dichromic acid, or any combination thereof.

32. The method of claim 27, wherein the oxidizing agent comprises O₂, O₃, CO₂, CrO₃, MnO₂, KMnO₄, K₂Cr₂O₇, or any combination thereof.

33. The method of claim 1, wherein at least one or more oxidized nanoparticles are dispersed in a fluid.

34. The method of claim 33, wherein the dispersion of oxidized nanoparticles is essentially uniform.

35. The method of claim 1, wherein the polymeric material further comprises glass, metal, ceramic, or any combination thereof.

36. The method of claim 1, wherein the polymeric material comprises an acrylonitrile polymer, an acrylonitrile co-polymer, or any combination thereof.

37. The method of claim 36, wherein the polymeric material comprises at least one acrylonitrile repeat group.

38. The method of claim 37, wherein the polymeric material comprises polyacrylonitrile.

39. The method of claim 2, wherein the cross-sectional dimension of the nano fiber is in the range of from about 1 nm to about 10,000 nm.

40. The method of claim 2, wherein the cross-sectional dimension of the nano fiber is in the range of from about 5 nm to about 500 nm.

41. The method of claim 2, wherein the cross-sectional dimension of the nanofiber is in the range of from about 10 nm to about 300 nm.

42. The method of claim 2, wherein the nanofiber is characterized as having a non-circular cross-sectional area.

43. The method of claim 42, wherein the cross-sectional area of the nanofiber is characterized as being a polygon having from 2 to 12 sides.

44. The method of claim 1, wherein the nanofiber is a solid core fiber or a hollow core fiber.

45. The method of claim 44, wherein a hollow core fiber comprises a core dimension in the range of from about lnm to about 5,000 nm.

46. The method of claim 1, wherein contacting comprises mixing, agitating, blending, spraying, and the like.

47. The method of claim 1 , further comprising removing at least a portion of the polyelectrolyte-linked polymeric material so as to expose at least a portion of the coating of nanoparticles.

48. The method of claim 47, wherein the removing comprises heating, selective dissolution, selective etching, or any combination thereof.

49. The method of claim 47, wherein the at least a portion of the exposed coating is characterized as being in the form of a pipe, a sheet, a bent sheet, a partially rolled sheet, a manifold, or any combination thereof.

50. The composition made according to the method of claim 1.

51. A polymeric composite, comprising:

a polymer; and

at least one nanoparticle bound to the polymer by at least one polyelectrolyte.

52. The polymeric composite of claim 51, wherein the polyelectrolyte comprises poly(diallyldimethylammonium) chloride.

53. The polymer composite of claim 51 , wherein the polymer comprises at least one nano fiber characterized as having a cross-sectional dimension in the range of from about 1 nm to about 10,000 nm, and an outer surface.

54. The polymeric composite of claim 51 , wherein the at least one nanoparticle comprises a nanotube, a multiwall carbon nanotube, a quantum dot nanocrystal, a polymeric nanoparticle, a nanodiamond, a metallic nanoparticle, or any combination thereof.

55. The polymeric composite of claim 54, wherein the nanotube comprises a single wall carbon nanotube having a diameter in the range of from about 0.4 nm to about 5 nm.

56. The polymeric composite of claim 55, wherein the nanotube comprises a single wall carbon nanotube having a diameter in the range of from 0.8 to about 4 nm.

57. The polymeric composite of claim 55, wherein the nanotube comprises a single wall carbon nanotube having a diameter in the range of from about 1 to about 5 ran.

58. The polymeric composite of claim 55, wherein the nanotube comprises a single wall carbon nanotube having a length in the range of from about 1 to about 100 microns.

59. The polymeric composite of claim 55, wherein the nanotube comprises a single wall carbon nanotube having a length in the range of from about 20 to about 80 microns.

60. The polymeric composite of claim 55, wherein the nanotube comprisea multiwall carbon nanotube having a diameter in the range of from about 0.5 run to about 300 nm.

61. The polymeric composite of claim 60, wherein the nanotube comprises a multiwall carbon nanotube having a diameter in the range of from 30 to about 70 nm.

62. The polymeric composite of claim 60, wherein the nanotube comprises a multiwall carbon nanotube having a diameter in the range of from about 40 to about 60 nm.

63. The polymeric composite of claim 60, wherein the nanotube comprises a multiwall carbon nanotube having a length in the range of from about 1 um to about 100 um.

64. The polymeric composite of claim 60, wherein the nanotube comprises a multiwall carbon nanotube having a length of from about 20 um about 80 um.

65. The polymeric composite of claim 50, further comprising at least one metal, at least one glass, at least one ceramic, or any combination thereof.

66. The polymeric composite of claim 65, wherein the polymeric material comprises an acrylonitrile polymer, an acrylonitrile co-polymer, or any combination thereof.

67. The polymeric composite of claim 66, wherein the polymeric material comprises at least one acrylonitrile repeat group.

68. The polymeric composite of claim 67, wherein the polymeric material comprises polyacrylonitrile.

69. The polymer composite of claim 50, wherein the polymeric material is in the form of at least one nano fiber characterized as having a cross-sectional dimension in the range of from about 1 nm to about 10,000 nm, and an outer surface.

70. The polymeric composite of claim 69, wherein the nano fiber cross-sectional dimension is in the range of from about 5 nm to about 5000 nm.

71. The polymeric composite of claim 69, wherein the nano fiber cross-sectional dimension is in the range of from about 7 nm to about 2500 nm.

72. The polymeric composite of claim 69, wherein the nanofiber cross-sectional dimension is in the range of from about 10 nm to about 300 nm.

73. The polymeric composite of claim 69, wherein the nanofiber is characterized as having a circular cross-sectional area.

74. The polymeric composite of claim 69, wherein the nanofiber is characterized as having a non-circular cross-sectional area.

75. The polymeric composite of claim 69, wherein the cross-sectional area of the nanofiber is characterized as being a polygon having from 2 to 12 sides.

76. The polymeric composite of claim 69, wherein the nanofiber is a solid core fiber or a hollow core fiber.

77. The polymeric composite of claim 76, wherein the hollow core fiber has a core diameter in the range of from about lnm to about 5,000 nm.

78. The polymeric composite of claim 51, wherein the electrolyte comprises a tetracoordinated nitrogen compound, or any copolymer thereof.

79. The polymeric composite of claim 78, wherein the tetracoordinated nitrogen compound comprises a tetraalyklammonium group.

80. The polymeric composite of claim 78, wherein the copolymer includes a random copolymer, a graft copolymer, an alternating copolymer, a block copolymer, a multiblock copolymer, a star copolymer, a dendrimer, or any combination thereof.