Abstract:
Embodiments of the invention provide a composite material having sufficient strength to form structural components of an aerospace vehicle, while also having sufficient electrical conductivity to dissipate electrostatic charge. As such, a composite material comprises an imide oligomer having thermally reactive endcaps and carbon nanofillers. The imide oligomer may comprise a phenyl ethynyl terminated imide. The phenylethynyl terminated imide may have a molecular weight of less than about 5000, or may have a molecular weight in the range of about 250 to about 5000. In particular, the phenylethynyl terminated imide may have a molecular weight of about 1500. The carbon nanofillers may be selected from the group consisting of carbon nanotubes, carbon nanofibcrs, expanded graphite, exfoliated graphite and combinations thereof. The carbon nanotubes may be selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes and combinations thereof.
Abstract:
Disclosed are mixtures comprising aqueous thiophene/anion dispersions, such as polythiophene/polystyrene sulfonate aqueous dispersions, and additives, as well as coatings produced therefrom. Coatings produced from these mixtures yield significant improvements in electrical conductivity without the need for a high temperature treatment as compared to coatings produced from unmodified aqueous polythiophene dispersions (e.g., Baytron®P) and to coatings produced from state-of the-art aqueous polythiophene-additive mixtures. These conductivity improvements are achieved without detracting from the optical transparency of the coating. Because characteristics of volume resistivity of less than 6.6 ohm-cm and optical transmission greater than 80% are important for conductive coating applications, coatings produced from the mixtures of the present invention have significant advantages over coatings produced from the state-of-the-art mixtures in many applications. Also disclosed are a variety of substrates or articles of manufacture coated with the mixtures of the present invention for use in various applications where a combination of high electrical conductivity, -excellent optical transparency and low temperature processing are important, such as electronic and optoelectronic devices.
Abstract:
The present invention is directed to the effective dispersion of carbon nanotubes (CNTs) into polymer matrices. The nanocomposites are prepared using polymer matrices and exhibit a unique combination of properties, most notably, high retention of optical transparency in the visible range (i.e., 400-800 nm), electrical conductivity, and high thermal stability. By appropriate selection of the matrix resin, additional properties such as vacuum ultraviolet radiation resistance, atomic oxygen resistance, high glass transition (T g ) temperatures, and excellent toughness can be attained. The resulting nanocomposites can be used to fabricate or formulate a variety of articles such as coatings on a variety of substrates, films, foams, fibers, threads, adhesives and fiber coated prepreg. The properties of the nanocomposites can be adjusted by selected of the polymer matrix and CNT to fabricate articles that possess high optical transparency and antistatic behavior.
Abstract:
Embodiments of the invention provide a composite material having sufficient strength to form structural components of an aerospace vehicle, while also having sufficient electrical conductivity to dissipate electrostatic charge. As such, a composite material comprises an imide oligomer having thermally reactive endcaps and carbon nanofillers. The imide oligomer may comprise a phenyl ethynyl terminated imide. The phenylethynyl terminated imide may have a molecular weight of less than about 5000, or may have a molecular weight in the range of about 250 to about 5000. In particular, the phenylethynyl terminated imide may have a molecular weight of about 1500. The carbon nanofillers may be selected from the group consisting of carbon nanotubes, carbon nanofibcrs, expanded graphite, exfoliated graphite and combinations thereof. The carbon nanotubes may be selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes and combinations thereof.
Abstract:
A dielectric material includes a network of nanosubstrates, such as but not limited to nanotubes, nanosheets, or other nanomaterials or nanostructures, a polymer base material or matrix, and nanoparticles constructed at least partially of an elemental metal. The network has a predetermined nano substrate loading percentage by weight with respect to a total weight of the dielectric material, and a preferential or predetermined longitudinal alignment with respect to an orientation of an incident electrical field. A method of forming the dielectric material includes depositing the metal-based nanoparticles onto the nanosubstrates and subsequently mixing these with a polymer matrix. Once mixed, alignment can be achieved by melt extrusion or a similar mechanical shearing process. Alignment of the nanosubstrate may be in horizontal or vertica! direction with respect to the orientation of an incident electrical field.
Abstract:
Novel compositions of matter comprise certain derivatives of 9,9-dialkyl fluorene diamine (AFDA). The resultant compositions, whether compositions of matter or monomers that are subsequently incorporated into a polymer, are unique and useful in a variety of applications. Useful applications of AFDA-based material include heavy ion radiation shielding components and components of optical and electronic devices.
Abstract:
The present invention relates generally to polyimides. It relates particularly to novel polyimides prepared from 2,3,3',4'-biphenyltetracarboxylic dianhydride and aromatic diamines. These novel polyimides have low color, good solubility, high thermal emissivity, low solar absorptivity and high tensile strength.
Abstract:
Spacecraft with electrostatic dissipative surfaces are disclosed herein. The surface has layer which includes a plurality of carbon nanotubes to incorporate electrical conductivity into space durable polymeric layers without degrading optical transparency, solar absorptivity or mechanical properties.
Abstract:
A dielectric material includes a network of nanosubstrates, such as but not limited to nanotubes, nanosheets, or other nanomaterials or nanostructures, a polymer base material or matrix, and nanoparticles constructed at least partially of an elemental metal. The network has a predetermined nano substrate loading percentage by weight with respect to a total weight of the dielectric material, and a preferential or predetermined longitudinal alignment with respect to an orientation of an incident electrical field. A method of forming the dielectric material includes depositing the metal-based nanoparticles onto the nanosubstrates and subsequently mixing these with a polymer matrix. Once mixed, alignment can be achieved by melt extrusion or a similar mechanical shearing process. Alignment of the nanosubstrate may be in horizontal or vertica! direction with respect to the orientation of an incident electrical field.
Abstract:
A dielectric material includes a network of nanosubstrates, such as but not limited to nanotubes, nanosheets, or other nanomaterials or nanostructures, a polymer base material or matrix, and nanoparticles constructed at least partially of an elemental metal. The network has a predetermined nano substrate loading percentage by weight with respect to a total weight of the dielectric material, and a preferential or predetermined longitudinal alignment with respect to an orientation of an incident electrical field. A method of forming the dielectric material includes depositing the metal-based nanoparticles onto the nanosubstrates and subsequently mixing these with a polymer matrix. Once mixed, alignment can be achieved by melt extrusion or a similar mechanical shearing process. Alignment of the nanosubstrate may be in horizontal or vertica! direction with respect to the orientation of an incident electrical field.