Abstract: A printed stretchable strain sensor comprises a seamless elastomeric body and a strain-sensitive conductive structure embedded in the seamless elastomeric body. The strain-sensitive conductive structure comprises one or more conductive filaments arranged in a continuous pattern. A method of printing a stretchable strain sensor comprises depositing one or more conductive filaments in a predetermined continuous pattern into or onto a support matrix. After the depositing, the support matrix is cured to embed a strain-sensitive conductive structure in a seamless elastomeric body.

Abstract: A printed tissue construct comprises one or more tissue patterns, where each tissue pattern comprises a plurality of viable cells of one or more predetermined cell types. A network of vascular channels interpenetrates the one or more tissue patterns. An extracellular matrix composition at least partially surrounds the one or more tissue patterns and the network of vascular channels. A method of printing a tissue construct with embedded vasculature comprises depositing one or more cell-laden filaments, each comprising a plurality of viable cells, on a substrate to form one or more tissue patterns. Each of the one or more tissue patterns comprises one or more predetermined cell types. One or more sacrificial filaments, each comprising a fugitive ink, are deposited on the substrate to form a vascular pattern interpenetrating the one or more tissue patterns. The vascular pattern and the one or more tissue patterns are at least partially surrounded with an extracellular matrix composition.

Abstract: A printed 3D functional part includes a 3D structure comprising a structural material, and at least one functional electronic device is at least partially embedded in the 3D structure. The functional electronic device has a base secured against an interior surface of the 3D structure. One or more conductive filaments are at least partially embedded in the 3D structure and electrically connected to the at least one functional electronic device.

Abstract: A three-dimensional (3D) electrode architecture for a microbattery includes an anode structure comprising one or more anode digits and a cathode structure comprising one or more cathode digits, the anode digits being positioned alternately with the cathode digits in an interdigitated configuration on a substrate, where each of the anode digits has a width wa and each of the cathode digits has a width wc. Each of the anode digits comprises an anode material deposited on a first current collector and extending to a height h above the first current collector, and each of the cathode digits comprises a cathode material deposited on a second current collector and extending to a height h, above the second current collector. A height-to-width aspect ratio ha/wa of the anode structure and a height-to-width aspect ratio hc/wc of the cathode structure are at least about 2.

Abstract: A viscoelastic ink for direct writing of hydrogel structures includes a long chain polymer and a photopolymerizable moiety, which may be a photopolymerizable monomer or a photopolymerizable group attached to the long chain polymer. The ink may also include a crosslinking agent, a photoinitiator, and water. The long chain polymer is present at a concentration greater than a critical overlap concentration c* of the long chain polymer in the ink.

Abstract: Encapsulated solids are made by first encapsulating precursor materials in a polymer shell. The precursors are some combination of solids, liquids, gases, and/or gels. The precursors are then transformed into solids by emplacement of the capsule in an environment where gas or fluid transport into or out of the polymer shell causes transformation into solids.

Abstract: An ink composition for making a conductive silver structure comprises a silver salt and a complex of (a) a complexing agent and a short chain carboxylic acid or (b) a complexing agent and a salt of a short chain carboxylic acid, according to one embodiment. A method for making a silver structure entails combining a silver salt and a complexing agent, and then adding a short chain carboxylic acid or a salt of the short chain carboxylic acid to the combined silver salt and a complexing agent to form an ink composition. A concentration of the complexing agent in the ink composition is reduced to form a concentrated formulation, and the silver salt is reduced to form a conductive silver structure, where the concentrated formulation and the conductive silver structure are formed at a temperature of about 120° C. or less.

Abstract: A method of making a composite material provides a composite material that includes a polymeric layer and a substrate, in contact with the polymeric layer, where the substrate includes a substrate matrix, a first microfluidic network in the substrate matrix and in fluid communication with the polymeric layer, and a polymerizer in the first microfluidic network. The method includes forming the first microfluidic network in the substrate matrix, where the first microfluidic network is in fluid communication with a surface of the substrate matrix. The method further includes contacting the surface of the substrate matrix with the polymeric layer, and placing the polymerizer in the first microfluidic network.

Abstract: Method and apparatus for separating a target substance from a fluid or mixture. Capsules having a coating and stripping solvents encapsulated in the capsules are provided. The coating is permeable to the target substance. The capsules having a coating and stripping solvents encapsulated in the capsules are exposed to the fluid or mixture. The target substance migrates through the coating and is taken up by the stripping solvents. The target substance is separated from the fluid or mixture by driving off the target substance from the capsules.

Abstract: A multinozzle deposition system for direct write applications comprises a body including a first network of microchannels embedded therein, where the first network of microchannels extends from a parent microchannel through a series of furcations to a plurality of branching microchannels. The series consists of k generations with furcation number m where the /cth generation includes mk branching microchannels. A first end of the body includes a single inlet to the parent microchannel and a second end of the body includes mk outlets from the branching microchannels, where k is an integer greater than or equal to 1 and m is an integer greater than or equal to 2. The body comprises a material having a sufficient rigidity to sustain a pressure in the microchannels of about 690 kPa or greater without distortion.

Abstract: Method and apparatus for separating a target substance from a fluid or mixture. Capsules having a coating and stripping solvents encapsulated in the capsules are provided. The coating is permeable to the target substance. The capsules having a coating and stripping solvents encapsulated in the capsules are exposed to the fluid or mixture. The target substance migrates through the coating and is taken up by the stripping solvents. The target substance is separated from the fluid or mixture by driving off the target substance from the capsules.

Abstract: A viscoelastic ink for direct writing of hydrogel structures includes a long chain polymer and a photopolymerizable moiety, which may be a photopolymerizable monomer or a photopolymerizable group attached to the long chain polymer. The ink may also include a crosslinking agent, a photoinitiator, and water. The long chain polymer is present at a concentration greater than a critical overlap concentration c* of the long chain polymer in the ink.

Abstract: Method and apparatus for separating a target substance from a fluid or mixture. Capsules having a coating and stripping solvents encapsulated in the capsules are provided. The coating is permeable to the target substance. The capsules having a coating and stripping solvents encapsulated in the capsules are exposed to the fluid or mixture. The target substance migrates through the coating and is taken up by the stripping solvents. The target substance is separated from the fluid or mixture by driving off the target substance from the capsules.

Abstract: A biphasic ink comprises a plurality of attractive particles, a plurality of repulsive particles, and a carrier liquid.

Abstract: A sensor array is provided including a plurality of fibers being woven to form 3-D periodic fiber structures. A selective number of the fibers include gaseous sensing materials to detect selective gases. A plurality of spacing elements provides adequate spacing between successively arranged nano-fibers. The nano-fibers and spacing elements are arranged to form a 3-D scaffolding structure for detecting specific or combinations of gaseous analytes.

Abstract: Devices that include hosts having internal microcapillary networks are disclosed. The microcapillary networks are formed from interconnected passageways. The interconnected passageways may be formed by removing a fugitive material from a cured host material that forms the host. The resultant host material has many applications, including use as a microfluidic device in applications ranging from fluid mixing to structural repair.

Abstract: The invention provides an ink which comprises: a metal oxide precursor, a stress reliever, and a solvent.

Abstract: Stabilized silver particles comprise particles comprising silver, a short-chain capping agent adsorbed on the particles, and a long-chain capping agent adsorbed on the particles. The short-chain capping agent is a first anionic polyelectrolyte having a molecular weight (Mw) of at most 10,000, and the long-chain capping agent is a second anionic polyelectrolyte having a molecular weight (Mw) of at least 25,000. The stabilized silver particles have a solid loading of metallic silver of at least 50 wt %.

Abstract: Polyelectrolyte inks comprising a solvent, a cationic polyelectrolyte dissolved in the solvent, and an anionic polyelectrolyte dissolved in the solvent, are described. The concentration of at least one of the polyelectrolytes in the solvent is in a semidilute regime.

Abstract: Devices that include hosts having internal microcapillary networks are disclosed. The microcapillary networks are formed from interconnected passageways. The interconnected passageways may be formed by removing a fugitive material from a cured host material that forms the host. The resultant host material has many applications, including use as a microfluidic device in applications ranging from fluid mixing to structural repair.