United States of America As Represented by the Administrator of Nasa

The United States of America As Represented by the Administrator of the

The United States of America As Represented by the United States

The United States of America As Represented by the Administrator

The United States of America As Represented by the Administrator of

National Institute of Aerospace Associates

Joseph G Smith, Jr

John W Connell

Paul M Hergenrother

Kent A Watson

Christopher J Wohl, Jr

Emilie J Siochi

Sayata Ghose

Donavon Mark Delozier

Cheol Park

Joycelyn S Harrison

Zoubeida Ounaies

Kenneth L Dudley

Robin E Southward

Craig M Thompson

Holly A Elliott

Raphael M Ottenbrite

Yi Lin

John M Gardner

Ronald K Penner

Christopher J Wohl

Donovan M Delozier

Michael J Fallbach

Frank M Palmieri

Lilly Lynn Balderson

Devon Beck

Robin L Cravey

Various embodiments provide ice mitigating surface coatings and methods for applying ice mitigating surface coatings. Various embodiment ice mitigating surface coatings may be formed by hydrolysis of one or more substituted n-alkyldimethylalkoxysilanes terminated with functionalities having the following characteristics with respect to water: 1) non-polar interactions; 2) hydrogen bonding through donor and acceptor interactions; or 3) hydrogen bonding through acceptor interactions only. The substituted n-alkyldimethylalkoxysilanes of the various embodiments may include methyl terminated species, hydroxyl terminated species, ethylene glycol terminated species, and methoxyethylene glycol terminated species. Various embodiment ice mitigating surface coatings may be applied to metal surfaces, such as aluminum surfaces. Various embodiment substituted n-alkyldimethylalkoxysilanes may have an aliphatic chain that is saturated and liner or branched or that is partially unsaturated and liner or branched.

Hydrogen-bonding surfaces for ice mitigation

Copoly(imide oxetane) materials are disclosed that can exhibit a low surface energy while possessing the mechanical, thermal, chemical and optical properties associated with polyimides. The copoly(imide oxetane)s are prepared using a minor amount of fluorinated oxetane-derived oligomer with sufficient fluorine-containing segments of the copoly(imide oxetane)s migrate to the exterior surface of the polymeric material to yield low surface energies. Thus the coatings and articles of manufacture made with the copoly(imide oxetane)s of this invention are characterized as having an anisotropic fluorine composition. The low surface energies can be achieved with very low content of fluorinated oxetane-derived oligomer. The copolymers of this invention can enhance the viability of polyimides for many applications and may be acceptable where homopolyimide materials have been unacceptable.

Anisotropic copoly(imide oxetane) coatings and articles of manufacture, copoly(imide oxetane)s containing pendant fluorocarbon moieties, oligomers and processes therefor

In an illustrative example, one or more coating formulations may be used and may have characteristics useful in different situations. During evaluations, a plurality of coating formulations comprising epoxy resins and diamine hardeners were prepared and evaluated with regards to impact ice adhesion strength and durability. Alone, such coating formulations provided a significantly reduced impact ice adhesion strength as compared to uncoated aluminum and/or stainless steel surfaces. However, a durability of the coatings, when applied to aluminum or stainless steel surfaces, was insufficient to be considered for use on external aircraft surfaces. By including nano-sized and/or micro-sized particles as additives to the coating formulations, resulted in improved durability without significantly reducing ice adhesion performance of the resin base.

Durable contamination resistant coatings

Embodiments provide ice adhesion mitigating surface coatings and methods for generating the same. Embodiments may provide anti-icing coating with at least one monomeric species exhibiting molecular flexibility. The molecular flexibility in the monomeric species may be imparted through an aliphatic or heteroaliphatic chain that may exist as a portion of the monomer backbone, as a pendant group, or as both the portion of the monomer backbone and the pendant group. In various embodiments epoxy coatings including an epoxy resin and an amine-terminated hardener may be generated. At least a portion of the amine-terminated hardener may include at least a monomeric species that exhibits molecular flexibility arising from an aliphatic chain or heteroaliphatic chain that may be within the polymer backbone and/or may persist as a pendant group.

Coatings with molecular flexibility for ice adhesion mitigation

Anisotropic copoly(imide oxetane) coatings and articles of manufacture, copoly (imide oxetane)s containing pendant fluorocarbon moieties, oligomers and processes therefor

Copoly(imide oxetane) materials are disclosed that can exhibit a low surface energy while possessing the mechanical, thermal, chemical and optical properties associated with polyimides. The copoly(imide oxetane)s are prepared using a minor amount of fluorinated oxetane-derived oligomer with sufficient fluorine-containing segments of the copoly(imide oxetane)s that migrate to the exterior surface of the polymeric material to yield low surface energies. Thus the coatings and articles of manufacture made with the copoly(imide oxetane)s of this invention are characterized as having an anisotropic fluorine composition. The low surface energies can be achieved with very low content of fluorinated oxetane-derived oligomer. The copolymers of this invention can enhance the viability of polyimides for many applications and may be acceptable where homopolyimide materials have been unacceptable.

Epoxy resin compositions prepared using amino terminated fluoro alkyl ethers. The epoxy resin compositions exhibit low surface adhesion properties making them useful as coatings, paints, moldings, adhesives, and fiber reinforced composites.

Fluorinated alkyl ether epoxy resin compositions and applications thereof

In the method of embodiments of the invention, the metal seeded carbon allotropes are reacted in solution forming zero valent metallic nanowires at the seeded sites. A polymeric passivating reagent, which selects for anisotropic growth is also used in the reaction to facilitate nanowire formation. The resulting structure resembles a porcupine, where carbon allotropes have metallic wires of nanometer dimensions that emanate from the seed sites on the carbon allotrope. These sites are populated by nanowires having approximately the same diameter as the starting nanoparticle diameter.

Preparation of metal nanowire decorated carbon allotropes

A process to modify a surface to provide reduced adhesion surface properties to mitigate insect residue adhesion. The surface may include the surface of an article including an aircraft, an automobile, a marine vessel, all-terrain vehicle, wind turbine, helmet, etc. The process includes topographically and chemically modifying the surface by applying a coating comprising a particulate matter, or by applying a coating and also topographically modifying the surface by various methods, including but not limited to, lithographic patterning, laser ablation and chemical etching, physical vapor phase deposition, chemical vapor phase deposition, crystal growth, electrochemical deposition, spin casting, and film casting.

Modified surface having low adhesion properties to mitigate insect residue adhesion

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 nanosubstrate 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 vertical direction with respect to the orientation of an incident electrical field.

Tailorable dielectric material with complex permittivity characteristics

An antenna includes a ground plane, a dielectric disposed on the ground plane, and an electrically-conductive radiator disposed on the dielectric. The dielectric includes at least one layer of a first dielectric material and a second dielectric material that collectively define a dielectric geometric pattern, which may comprise a fractal geometry. The radiator defines a radiator geometric pattern, and the dielectric geometric pattern is geometrically identical, or substantially geometrically identical, to the radiator geometric pattern.

Antenna with dielectric having geometric patterns

Growing community of inventors

Smithfield, VA, United States of America

Joseph G Smith, Jr