Abstract: Disclosed herein is a method of preparing a polymer dispersion including combining a first solution with a second solution to provide an emulsion, and removing the first solvent from the emulsion to provide a dispersion including a plurality of polymer particles. The first solution includes a first solvent, a polyetherimide, a polycarbonate, or a combination of at least one of the foregoing, and optionally a nonionic surfactant. The second solution includes an aqueous solvent, and optionally a nonionic surfactant. The polymer particles have an average particle size (D50) of less than or equal to 20 micrometers. Also described are polyetherimide dispersions including a plurality of polyetherimide particles, wherein at least 90% of the particles have a particle size less than or equal to 14 micrometers, a nonionic surfactant, and an aqueous carrier.

Abstract: A reinforced paper includes a nonwoven fibrous mat impregnated with a polyetherimide composition. The nonwoven fibrous mat includes a reinforcing fiber, a high strength toughening fiber, or a combination thereof. The polyetherimide composition includes a polyetherimide having repeating units as defined herein. A method of making a reinforced paper is also disclosed. The method includes contacting at least a portion of a nonwoven fibrous mat with a composition to form a pre-preg, and heating under conditions effective to provide the reinforced paper. Articles including the reinforced paper are also described.

Abstract: Provided are amorphous and at least partially crystalline polyetherimide compositions having a comparatively narrow particle size distribution and are particularly suited for additive manufacturing processes. The compositions comprise a population of polyetherimide particulates are characterized as having a zero-shear viscosity sufficiently low so as to achieve a coalescence of at least 0.5, and preferably of about 1.0, as characterized by the Frenkel model at a temperature less than 450° C.

Abstract: A process is disclosed for synthesis of a poly(amic acid), including reacting a dianhydride and a diamine in the presence of a tertiary amine, tertiary ammonium salt, tertiary ammonium hydroxide, secondary amine, secondary ammonium salt, secondary ammonium hydroxide, quaternary ammonium salt, quaternary ammonium hydroxide, ammonium hydroxide, or a combination comprising at least one of the foregoing, in water, at a temperature of 60 C to 180 C, or 60 C to 100 C, or 100 C to 180 C, under an inert atmosphere, with agitation, to produce an aqueous poly(amic acid).

Abstract: A method of making an article includes converting a first amorphous polymer to an at least partially crystalline polymeric powder composition and powder bed fusing the at least partially crystalline polymer powder composition to form a three-dimensional article including a second amorphous polymer.

Abstract: A process for the manufacture of thermoplastic polymer particles in a yield of greater than 70% is described. The process includes dissolving a thermoplastic polymer in an organic solvent capable of dissolving the polymer to form a solution, emulsifying the solution by combining the solution with water and a surfactant to form an emulsion, removing the organic solvent to form a slurry, and recovering thermoplastic polymer particles having a diameter of less than 150 micrometers and in a yield of greater than 70%. The water is present in the emulsion in an amount of 5 to less than 50 weight percent. The thermoplastic polymer particles exhibit a combination of size characteristics. Thermoplastic polymer particles and articles prepared therefrom are also described.

Abstract: A process for the manufacture of thermoplastic polymer particles, including combining a first solution including a thermoplastic polymer and an organic solvent with a second solution including an aqueous solvent and a surfactant to provide an emulsion. The emulsion is transferred into a receiving water to remove the organic solvent and form an aqueous dispersion including a plurality of thermoplastic polymer particles dispersed in the aqueous solvent. The thermoplastic polymer particles having a D50 of 20 to 100 ?m are recovered in a yield of greater than 85%. Thermoplastic polymer particles prepared according to the method are also disclosed.

Abstract: A copolyimide includes the reaction product of an aromatic dianhydride component including a substituted or unsubstituted pyromellitic dianhydride or a functional derivative thereof and an aromatic bis(ether phthalic anhydride) or a functional derivative thereof, and an organic diamine component comprising a substituted or unsubstituted phenylene diamine and a diaminodiphenyl sulfone. Articles and compositions including the copolyimides and methods of manufacturing a polyimide film are also described.

Abstract: A method of preparing polymer particles includes combining a polyetherimide and a solvent at a first temperature to provide a slurry, wherein the polyetherimide is not soluble in the solvent at the first temperature; heating the slurry to a second temperature and at a pressure effective to dissolve the polyetherimide in the solvent to provide a homogenous solution; cooling the homogenous solution to a third temperature to provide a dispersion including a plurality of polymer particles; and isolating the polymer particles. The polymer particles have a Dv90 particle size of less than or equal to 250 micrometers. Polymers powders prepared according to the method are also described herein, wherein the powder includes a plurality of semi-crystalline polymer particles having a Dv90 of less than or equal to 250 micrometers.

Abstract: Disclosed herein is a friable polyimide powder having a weight average molecular weight, as determined by gel permeation chromatography (GPC) using polystyrene standards, of less than or equal to 24,500 Daltons and a reactive aromatic amine end group concentration greater than or equal to 3 mole percent, wherein 90 weight percent of the powder particles are reducible to less than or equal to 75 micrometers by mechanical grinding. Also disclosed is a method of making the friable polyimide powder, a processed polyimide resulting from the friable polyimide powder and compositions comprising the processed polyimide.

Abstract: A method of manufacturing polyimide particles includes combining a polyimide solution including a polyimide and an organic solvent with an aqueous solution including water in the presence of an emulsifying surfactant at a shear rate from 1,000 to 3,000 revolutions per minute to form an emulsion. The method further includes removing the organic solvent to form an aqueous polymer dispersion including polyimide particles, and recovering the polyimide particles. The polyimide particles have a spherical morphology and a volume based D10 diameter from 3 to 50 micrometers, a volume based D90 diameter from 3 to 80 micrometers, and a volume based D100 diameter from 3 to 100 micrometers.

Abstract: A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C4-40 bisanhydride, and a substituted or unsubstituted divalent C1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.

Abstract: A method for manufacturing a poly(imide) prepolymer powder includes combining a bisanhydride powder or organic diamine and a solvent comprising an alcohol, a water-soluble ketone or water to form a mixture, adding an organic diamine or bisanhydride powder to the mixture to form a poly(imide) prepolymer, and removing the solvent to provide the poly(imide) prepolymer powder. A method for manufacturing a poly(imide) prepolymer varnish includes combining a bisanhydride powder or organic diamine and a solvent comprising an alcohol, a water-soluble ketone or water to form a mixture, and adding an organic diamine or bisanhydride powder to the mixture to form a poly(imide) prepolymer. The method of manufacturing the varnish further includes at least one of adding an effective amount of a secondary or tertiary amine to solubilize the poly(imide) prepolymer powder, heating the mixture to a temperature effective to provide the varnish, or agitating the mixture to provide the varnish.

Abstract: A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C4-40 bisanhydride, and a substituted or unsubstituted divalent C1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.

Abstract: A polyimide-forming composition includes a polyimide prepolymer, an amine, and a solvent comprising a C1-6 alcohol. A method of manufacturing the polyimide-forming composition is disclosed. The method includes heating a substituted or unsubstituted C4-40 bisanhydride in a C1-6 alcohol to dissolve the bisanhydride, adding a substituted or unsubstituted divalent C1-20 diamine to form a polyimide prepolymer, and adding the amine in an amount effective to solubilize the polyimide prepolymer in the C1-6 alcohol, in a solution of the C1-6 alcohol and deionized water, or in deionized water. A method of manufacturing an article including a polyimide is also disclosed.

Abstract: A method comprises preparing or receiving a polyetherimide precursor solution including (i) a solvent comprising water, aliphatic alcohol, or a mixture thereof; (ii) an amine additive comprising a secondary or tertiary amine; and (iii) a polyetherimide precursor dissolved and dissociated in the solvent. The method further comprises at least partially coating or impregnating one or more reinforcement structures with the polyetherimide precursor solution and polymerizing the one or more polyetherimide precursor reagents to form a polyetherimide matrix such that the one or more reinforcement structures are at least partially embedded in the polyetherimide matrix to provide a composite article.

Abstract: A process for the manufacture of thermoplastic polymer particles, including combining a first solution including a thermoplastic polymer and an organic solvent with a second solution including an aqueous solvent and a surfactant to provide an emulsion. The emulsion is transferred into a receiving water to remove the organic solvent and form an aqueous dispersion including a plurality of thermoplastic polymer particles dispersed in the aqueous solvent. The thermoplastic polymer particles having a D50 of 20 to 100 ?m are recovered in a yield of greater than 85%. Thermoplastic polymer particles prepared according to the method are also disclosed.

Abstract: A system comprises a build area, a precursor feed system to feed polyimide precursor to the build area, and a laser system comprising a laser device to emit a focused energy beam onto the build area, and a laser actuator to aim the focused energy onto selected target locations of the build area in order to selectively initiate polymerization of at least a portion of the polyimide precursor into a structure including polyimide. A method comprises feeding a polyimide precursor to a build area and selectively directing a focused energy beam to the build area to selectively initiate polymerization of at least a portion of the polyimide precursor into a structure including polyimide.

Abstract: Disclosed herein is a method of preparing a polymer dispersion including combining a first solution with a second solution to provide an emulsion, and removing the first solvent from the emulsion to provide a dispersion including a plurality of polymer particles. The first solution includes a first solvent, a polyetherimide, a polycarbonate, or a combination of at least one of the foregoing, and optionally a nonionic surfactant. The second solution includes an aqueous solvent, and optionally a nonionic surfactant. The polymer particles have an average particle size (D50) of less than or equal to 20 micrometers. Also described are polyetherimide dispersions including a plurality of polyetherimide particles, wherein at least 90% of the particles have a particle size less than or equal to 14 micrometers, a nonionic surfactant, and an aqueous carrier.

Abstract: A method of manufacturing a polyimide prepreg, including: coating a substrate with an aqueous polymer dispersion comprising polyimide particles having a spherical morphology and a volume based D100 diameter less than 100 micrometers and a volume based D90 diameter less than 60 micrometers and a volume based D50 diameter less than 40 micrometers, to form a coated substrate; and heating the coated substrate to form a polyimide prepreg. The prepregs can be formed into laminates or 3-dimensional composite articles.