Abstract: A composition of matter useful as a bioadhesive including a bistable adhesive polymer. The bistable adhesive polymer includes one or more polymer backbones; side-chains attached to each of the polymer backbones; and one or more transition temperatures between a crystalline state and an amorphous state. The one or more transition temperatures are such that the polymer transitions from the crystalline state to the amorphous state upon physical contact with biological tissue having a temperature higher than the transition temperature. The polymer adheres or attaches to the biological tissue in the amorphous state and can be peeled from the biological tissue when cooled below the transition temperature to the crystalline state.

Abstract: A device comprising one or more heat transfer laminates each including an electrode, a first dielectric layer on a first side of the electrode, and a second dielectric layer on a second side of the electrode; a plurality of flexible electrocaloric elements, each of the flexible electrocaloric elements including an electrocaloric material layer, a flexible electrode layer on the electrocaloric layer, one or more fixed portions each attached to one of heat transfer laminates, and a movable portion that is movable with respect to the one of the heat transfer laminates.

Abstract: A solid state thermochromic polymer film comprising two or more separated solid phases with matched refractive indices, wherein the separated solid phases are transparent; and one of the phases undergoes a crystal melting above a threshold temperature resulting in significant reduction of its refractive index. The one of the phases undergoing the crystal melting becomes opaque when its temperature rises above said threshold temperature; and reverts to being transparent when its temperature lowers to an ambient temperature below said threshold temperature. In one example, the new thermochromic phase-changing copolymer with switchable optical transparency is fabricated via copolymerizing hydrophilic poly(hydroxyethyl acrylate) and hydrophobic poly(hexadecyl acrylate-tetradecyl acrylate). The polymer film is transparent due to matched refractive indices of the phase separated domains, but turns opaque when the long alkyl chains undergoes crystalline melting above 28-32° C.

Abstract: A device including a bottom electrode on a substrate and a top electrode on a substrate separated by a fixed distance from each other. Semi-insulator layers with proper electrical conductivity are attached to the bottom and top electrodes. Disposed between the substrates is a flexible S-shaped polymer stack having electrode layers with one end of the stack attached to the top substrate and the other end in contact with the bottom substrate. When a voltage is applied between the stack and the electrode layer on the bottom substrate, the stack is induced by electrostatic force to deflect in a rolling wave-like motion. While the voltage applied between the stack and bottom electrode is turned off, the static charges on the semi-insulator layer can move away quickly due to the proper electrical conductivity of the semi-insulator layer.

Abstract: A smart window including a solid polymer film which is opaque at an ambient temperature and transparent at an elevated temperature; a transparent heater to supply uniform heating to at least a part of the solid polymer film; and a power supply connected to the transparent heater.

Abstract: A solid-state heat transporting device including a heat transporting element whose uniformity of contact with one or multiple surfaces is controllable so that various amounts of heat may be transported to and from the one or multiple surfaces. The heat transporting element uses the electrocaloric effect to absorb and release the heat and the uniformity of contact is controlled using an electrostatic effect which may change the shape of the heat transporting element. In one embodiment, the heat transporting element is an electrostatically actuated P(VDF-TrFE-CFE) polymer stack achieving a high specific cooling power of 2.8 W/g and a COP of 13 (the highest reported coefficient of performance to date) when used as a cooling device.

Abstract: A device comprising one or more heat transfer laminates each including an electrode, a first dielectric layer on a first side of the electrode, and a second dielectric layer on a second side of the electrode; a plurality of flexible electrocaloric elements, each of the flexible electrocaloric elements including an electrocaloric material layer, a flexible electrode layer on the electrocaloric layer, one or more fixed portions each attached to one of heat transfer laminates, and a movable portion that is movable with respect to the one of the heat transfer laminates.

Abstract: A solid-state heat transporting device including a heat transporting element whose uniformity of contact with one or multiple surfaces is controllable so that various amounts of heat may be transported to and from the one or multiple surfaces. The heat transporting element uses the electrocaloric effect to absorb and release the heat and the uniformity of contact is controlled using an electrostatic effect which may change the shape of the heat transporting element. In one embodiment, the heat transporting element is an electrostatically actuated P(VDF-TrFE-CFE) polymer stack achieving a high specific cooling power of 2.8 W/g and a COP of 13 (the highest reported coefficient of performance to date) when used as a cooling device.

Abstract: In an embodiment of the invention, the device comprises a bottom electrode on a substrate and a top electrode on a substrate separated by a fixed distance from each other. Semi-insulator layers with proper electrical conductivity are attached to the bottom and top electrodes. Disposed between the substrates is a flexible S-shaped polymer stack having electrode layers with one end of the stack attached to the top substrate and the other end in contact with the bottom substrate. When a voltage is applied between the stack and the electrode layer on the bottom substrate, the stack is induced by electrostatic force to deflect in a rolling wave-like motion.

Abstract: A transparent conductive film having a first surface and a second surface, the second surface opposite the first surface; and at least one thermally stable substrate attached to the second surface. The transparent conductive film includes a plurality of thermally stable nanowires embedded within at least one polymer binder, the thermally stable nanowires include metal nanowires, the first surface includes a conductive surface of a plurality of the nanowires, the transparent conductive film has a sheet resistance that degrades by no more than 5% when heated to 300° C. for 1 hour, and the transparent conductive film has a transmittance at a wavelength of 550 nm that decreases by no more than 5% when heated to 300° C. for 1 hour. In one example, silver nanowires are made thermally stable using a thin layer of ZnO deposited using atomic layer deposition.

Abstract: A method for producing flexible, nanoparticle-polymer composite electrodes is described. Conductive nanoparticles, preferably metal nanowires or nanotubes, are deposited on a smooth surface of a platform to produce a porous conductive layer. A second application of conductive nanoparticles or a mixture of nanoparticles can also be deposited to form a porous conductive layer. The conductive layer is then coated with at least one coating of monomers that is polymerized to form a conductive layer-polymer composite film. Optionally, a protective coating can be applied to the top of the composite film. In one embodiment, the monomer coating includes light transducing particles to reduce the total internal reflection of light through the composite film or pigments that absorb light at one wavelength and re-emit light at a longer wavelength. The resulting composite film has an active side that is smooth with surface height variations of 100 nm or less.

Abstract: A method for the synthesis and use of transparent bulk conjugated polymers prepared from liquid monomers via bulk polymerization. The liquid monomer contains pi-electron conjugated moieties and polymerizable moieties. The monomer solution may also have functionalizing additives such as a luminescence additive that includes organic dyes, luminescent molecules, fluorescent compounds, phosphorescent compounds, and luminescent quantum dots. The monomer solution may also have sensitizing additives such as high-energy photo sensitizing compounds, nanoparticles of compounds containing atoms with atomic numbers greater than 52 and neutron sensitizing additives. The monomer solution is polymerized by heating to an elevated temperature with or without addition of an initiator. Alternatively, the monomer is polymerized by photo-induced polymerization. A photoinitiator may be employed to initiate the photopolymerization. Scintillation materials with significant light yields are illustrated.

Abstract: A method for producing high efficiency organic light emitting devices, that have an organic semiconductor active layer sandwiched between electrodes where at least one of the electrodes is a film of conductive nanowires, carbon nanoparticles, light scattering nanoparticles and a polymer support. The light scattering nanoparticles can be incorporated in the conductive nanowires, carbon nanoparticle or polymer support elements of the electrode. The second electrode can be identical to the first to provide a symmetrical device or can be a conductive paste or metal layer. The entire process, including the formation of both of the electrodes, the emissive polymer layer, and the substrate, may be carried out by solution processing.

Abstract: An electroactive register is shown configured to modulate the incoming airflow in an HVAC duct to form two localized airflows: a first a high-speed airflow to form a conical air curtain surrounding an occupant and limiting air exchange between inside air and air outside of the air curtain, and a second a low-speed airflow (also referred to as center air) inside the air curtain to cool or heat the occupant comfortably. The temperature gradient between inside and outside of the air curtain enables expansion of set points of HVAC. The electroactive register is also able to improve personal comfort as the center air FLS can be customized for each individual occupant.

Abstract: A method for producing high efficiency organic light emitting devices, that have an organic semiconductor active layer sandwiched between electrodes where at least one of the electrodes is a film of conductive nanowires, carbon nanoparticles, light scattering nanoparticles and a polymer support. The light scattering nanoparticles can be incorporated in the conductive nanowires, carbon nanoparticle or polymer support elements of the electrode. The second electrode can be identical to the first to provide a symmetrical device or can be a conductive paste or metal layer. The entire process, including the formation of both of the electrodes, the emissive polymer layer, and the substrate, may be carried out by solution processing.

Abstract: Described herein are transducers and their fabrication. The transducers convert between mechanical and electrical energy. Some transducers of the present invention include a pre-strained polymer. The pre-strain improves the conversion between electrical and mechanical energy. The present invention provides methods for fabricating electromechanical devices including one or more electroactive polymers.

Abstract: A method for the synthesis and use of transparent bulk conjugated polymers prepared from liquid monomers via bulk polymerization. The liquid monomer contains pi-electron conjugated moieties and polymerizable moieties. The monomer solution may also have functionalizing additives such as a luminescence additive that includes organic dyes, luminescent molecules, fluorescent compounds, phosphorescent compounds, and luminescent quantum dots. The monomer solution may also have sensitizing additives such as high-energy photo sensitizing compounds, nanoparticles of compounds containing atoms with atomic numbers greater than 52 and neutron sensitizing additives. The monomer solution is polymerized by heating to an elevated temperature with or without addition of an initiator. Alternatively, the monomer is polymerized by photo-induced polymerization. A photoinitiator may be employed to initiate the photopolymerization. Scintillation materials with significant light yields are illustrated.

Abstract: The synthesis, characterization, optical and electrochemical properties of a regioregular copolymer, poly(3-octylthiophene-2,5-diyl-co-3-decyloxythiophene-2,5-diyl) (POT-co-DOT), and an alternating regioregular copolymer poly{(9,9-dioctylfluorene)-2,7-diyl-alt-[4,7-bis(3-decyloxythien-2-yl)-2,1,3-benzothiadiazole]-5?,5?-diyl} (PF-co-DTB) is disclosed. The incorporation of 3-alkoxythiophene units onto the conjugated backbones enhances the electron-donating property of the polymer and lowers its bandgap. The fabrication and performance of photovoltaic cells with bulk heterojunction architecture based on blends of these copolymers with PCBM are also described.

Abstract: The present invention provides electroactive polymers, transducers and devices that maintain pre-strain in one or more portions of an electroactive polymer. Electroactive polymers described herein may include a pre-strained portion and a stiffened portion configured to maintain pre-strain in the pre-strained portion. One fabrication technique applies pre-strain to a partially cured electroactive polymer. The partially cured polymer is then further cured to stiffen and maintain the pre-strain. In another fabrication technique, a support layer is coupled to the polymer that maintains pre-strain in a portion of an electroactive polymer. Another embodiment of the invention cures a polymer precursor to maintain pre-strain in an electroactive polymer.

Abstract: The present invention relates to animated devices that include one or more electroactive polymer transducers. When actuated by electrical energy, an electroactive polymer produces mechanical deflection in one or more directions. This deflection may be used to produce motion of a feature included in an animated device. Electroactive polymer transducers offer customizable shapes and deflections. Combining different ways to configure and constrain a polymer, different ways to arrange active areas on a single polymer, different animated device designs, and different polymer orientations, permits a broad range of animated devices that use an electroactive polymer transducer to produce motion. These animated devices find use in a wide range of animated device applications.