Abstract: The disclosure relates to methods of forming three-dimensional (3D) polymeric articles and additive manufacturing apparatuses for the same. The methods include providing a polymeric solution comprising a polymer dissolved in a solvent; providing a non-solvent, wherein the solvent is miscible in the non-solvent, and the polymer is insoluble in the non-solvent; and injecting the polymeric solution into the non-solvent in a pre-determined 3D pattern to provide a 3D polymeric article.

Abstract: A method of making an isocyanurate polymer is disclosed. An isocyanate including at least one of an aromatic isocyanate and an aliphatic isocyanate is provided. A trimerization catalyst including at least one of an amine catalyst, an organometallic compound, and an imidazole compound is provided. A reaction mixture that is substantially free of reactive hydrogen is formed by mixing less than about twenty percent by total weight of said reaction mixture of an epoxide with said isocyanate. The trimerization catalyst is mixed with the reaction mixture. The reaction mixture is cured to produce a polymer composition including a reaction product of two or more isocyanates.

Abstract: A method of producing a reinforced polymer composite includes placing reinforcement solids a die defining a die cavity. A liquid reaction mixture including an aromatic polyisocyanate and initiating reaction of said aromatic polyisocyanate is infused with a catalyst composition forming an aromatic isocyanurate based polymer reaction mixture impregnates the reinforcing solids with using the cavity for forming the aromatic isocyanurate based polymer reaction mixture. The cavity defined by the die is heated to at least 80° C. for a period required to form a polymer reaction product producing the reinforced polymer composite.

Abstract: A method of making an isocyanurate polymer is disclosed. An isocyanate including at least one of an aromatic isocyanate and an aliphatic isocyanate is provided. A trimerization catalyst including at least one of an amine catalyst, an organometallic compound, and an imidazole compound is provided. A reaction mixture that is substantially free of reactive hydrogen is formed by mixing less than about twenty percent by total weight of said reaction mixture of an epoxide with said isocyanate. The trimerization catalyst is mixed with the reaction mixture. The reaction mixture is cured to produce a polymer composition including a reaction product of two or more isocyanates.

Abstract: The disclosure relates to methods of forming three-dimensional (3D) polymeric articles and additive manufacturing apparatuses for the same. The methods include providing a polymeric solution comprising a polymer dissolved in a solvent; providing a non-solvent, wherein the solvent is miscible in the non-solvent, and the polymer is insoluble in the non-solvent; and injecting the polymeric solution into the non-solvent in a pre-determined 3D pattern to provide a 3D polymeric article.

Abstract: The present invention relates to a reaction mixture including one or more polyfunctional isocyanates such that the average isocyanate functionality of the mixture is greater than 2.1, and a catalyst composition including at least one trimerization catalyst and at least one epoxide group; and curing the reaction mixture to give a cured polymer composition made up of the reaction product of isocyanates with themselves.

Abstract: The present invention relates to a reaction mixture including one or more polyfunctional isocyanates such that the average isocyanate functionality of the mixture is greater than 2.1, and a catalyst composition including at least one trimerization catalyst and at least one epoxide group; and curing the reaction mixture to give a cured polymer composition made up of the reaction product of isocyanates with themselves.

Abstract: A ?-phase PVDF is prepared through a controllable dehydrofluorination under either a basic or high temperature condition. PVDF is degraded by losing hydrogen fluoride (HF) and either carbon-carbon double bonds form in the molecular backbone or single bonds form crosslinking the two polymer chains. These changes in structure influence the crystallization behavior of PVDF and therefore, influence the electrical properties by changing the arrangement of the dipoles.

Abstract: A shape-memory self-healing polymeric network (SMSHP) is useful as a molded part, a coating, or as a matrix for a composite that can be repaired by heating to a controlled temperature. The SMSHP has thermally reversible repeating units where a thermally reversible adduct is situated between two common linking units formed during a polymerization process between thermally reversible monomers and cross-linking monomers. Optionally, other repeating units can be present from other monomers. Shape-memory results when the SMSHP is warmed to a temperature in excess of its glass transition temperature and self-healing then proceeds when a higher temperature is achieved where thermally reversible adducts dissociates to complementary groups that subsequently reform the adduct without distortion of the memorized shape. The thermally reversible adducts can be Diels-Alder (DA) adducts in a polyurethane, poly urea, or amine epoxy SMSHP network.

Abstract: A method for synthesizing a piezoelectric material is provided. The method includes dehydrofluorinating a fluoropolymer precursor by incubating the fluoropolymer precursor in the presence of a base, wherein the fluoropolymer precursor comprises poly(vinylidene fluoride) or a copolymer of vinylidene fluoride; and isolating an at least partially dehydrofluorinated fluoropolymer solid having ?-phase and that exhibits melt flow processability at a temperature of greater than or equal to about 150° C. The at least partially dehydrofluorinated fluoropolymer solid is capable of forming a solid piezoelectric fluoropolymer material having ?-phase in an amount sufficient to exhibit a piezoelectric strain coefficient d31 absolute value of greater than or equal to about 25 pm/V.

Abstract: A ?-phase PVDF is prepared through a controllable dehydrofluorination under either a basic or high temperature condition. PVDF is degraded by losing hydrogen fluoride (HF) and either carbon-carbon double bonds form in the molecular backbone or single bonds form crosslinking the two polymer chains. These changes in structure influence the crystallization behavior of PVDF and therefore, influence the electrical properties by changing the arrangement of the dipoles.

Abstract: A shape-memory self-healing polymeric network (SMSHP) is useful as a molded part, a coating, or as a matrix for a composite that can be repaired by heating to a controlled temperature. The SMSHP has thermally reversible repeating units where a thermally reversible adduct is situated between two common linking units formed during a polymerization process between thermally reversible monomers and cross-linking monomers. Optionally, other repeating units can be present from other monomers. Shape-memory results when the SMSHP is warmed to a temperature in excess of its glass transition temperature and self-healing then proceeds when a higher temperature is achieved where thermally reversible adducts dissociates to complementary groups that subsequently reform the adduct without distortion of the memorized shape. The thermally reversible adducts can be Diels-Alder (DA) adducts in a polyurethane, poly urea, or amine epoxy SMSHP network.

Abstract: In an embodiment of the invention, a laminar composite has at least one interlaminar reinforced interface comprising a dispersion of binding-agent-treated low-dimensional nanoparticles with a large aspect ratio fixed between adjacent lamina by residues of the binding agents. In another embodiment of the invention, a method to prepare a laminar composite having reinforced interfaces involves the deposition of binding-agent-treated low-dimensional nanoparticles from a solution or suspension onto the surface or a prepreg sheet, where, optionally, after removal of the liquid that comprises the solution or suspension, sheets of the prepreg are layed-up and cured to form the laminar composite.

Abstract: A nano-electromechanical system comprises piezoelectric vertically aligned BaTiO3 nanowire arrays for energy-harvesting applications, sensors, and other applications. The aligned piezoelectric nanowire arrays provide highly accurate nano-electromechanical system-based dynamic sensor with a wide operating bandwidth and unity coherence and energy harvesters at low frequencies. The growth of vertically aligned (B45-mm long) barium titanate nanowire arrays is realized through a hydrothermal synthesis.

Abstract: A nano-electromechanical system comprises piezoelectric vertically aligned BaTiO3 nanowire arrays for energy-harvesting applications, sensors, and other applications. The aligned piezoelectric nanowire arrays provide highly accurate nano-electromechanical system-based dynamic sensor with a wide operating bandwidth and unity coherence and energy harvesters at low frequencies. The growth of vertically aligned (B45-mm long) barium titanate nanowire arrays is realized through a hydrothermal synthesis.

Abstract: In an embodiment of the invention, a laminar composite has at least one interlaminar reinforced interface comprising a dispersion of binding-agent-treated low-dimensional nanoparticles with a large aspect ratio fixed between adjacent lamina by residues of the binding agents. In another embodiment of the invention, a method to prepare a laminar composite having reinforced interfaces involves the deposition of binding-agent-treated low-dimensional nanoparticles from a solution or suspension onto the surface or a prepreg sheet, where, optionally, after removal of the liquid that comprises the solution or suspension, sheets of the prepreg are layed-up and cured to form the laminar composite.

Abstract: Fiber reinforced composites fabricated using a low-temperature, solution-based growth of nanowires such as ZnO nanowires on the surface of the reinforcing fibers such as carbon fibers and functionalized aramid fibers. The composites with nanowire interphase may have an enhanced fiber/matrix interface strength and a comparable in-plane strength, as compared to similar composites without such nanowire interphase.