The present invention aims to provide a method for producing a porous substrate containing a bioabsorbable polymer and heparin in a simple manner without use of a surfactant, a porous substrate containing a bioabsorbable polymer and heparin, and an artificial blood vessel. The present invention provides a method for producing a porous substrate containing a bioabsorbable polymer and heparin, including: a solution preparing step of preparing a heparin-bioabsorbable polymer solution having heparin uniformly dispersed therein and a bioabsorbable polymer dissolved therein, using the bioabsorbable polymer, the heparin, a solvent 1 that is a poor solvent having a lower solvency for the bioabsorbable polymer, a solvent 2 that is a good solvent having a higher solvency for the bioabsorbable polymer and is incompatible with the solvent 1, and a common solvent 3 compatible with the solvent 1 and the solvent 2; a precipitating step of cooling the heparin-bioabsorbable polymer solution to precipitate a porous body containing the bioabsorbable polymer and the heparin; and a freeze-drying step of freeze-drying the porous body containing the bioabsorbable polymer and the heparin to provide a porous substrate containing the heparin.

A method of fabricating a polishing pad includes determining a desired distribution of voids to be introduced within a polymer matrix of a polishing layer of the polishing pad. Electronic control signals configured to be read by a 3D printer are generated which specify the locations where a polymer matrix precursor is to be deposited, and specify the locations of the desired distribution of voids where no material is to be deposited. A plurality of layers of the polymer matrix corresponding to the plurality of the first locations is successfully deposited with the 3D printer. Each layer of the plurality of layers of polymer matrix is deposited by ejecting a polymer matrix precursor from a nozzle. The polymer matrix precursor is solidified to form a solidified polymer matrix having the desired distribution of voids.

A method of fabricating a polishing pad includes determining a desired distribution of voids to be introduced within a polymer matrix of a polishing layer of the polishing pad. Electronic control signals configured to be read by a 3D printer are generated which specify the locations where a polymer matrix precursor is to be deposited, and specify the locations of the desired distribution of voids where no material is to be deposited. A plurality of layers of the polymer matrix corresponding to the plurality of the first locations is successfully deposited with the 3D printer. Each layer of the plurality of layers of polymer matrix is deposited by ejecting a polymer matrix precursor from a nozzle. The polymer matrix precursor is solidified to form a solidified polymer matrix having the desired distribution of voids.

A method of producing a metal form containing dispersed aerogel particles impregnated with polymers comprising a method of impregnating an aerogel with polymers, placing the aerogel impregnated with polymers within a dissolved polymer, cooling the dissolved polymer to create a polymer form with dispersed aerogel particles impregnated with polymers, adding molten metal to the polymer form, vaporizing the polymer form, replacing the polymer form with molten metal, and cooling the molten metal to yield a metal form containing dispersed aerogel particles impregnated with polymers. Dispersing the aerogel particles impregnated with polymers within the polymer form prior to adding molten metal allows the aerogel particles to be fully dispersed throughout the metal form.

In general, in various embodiments, the present disclosure is directed systems and methods for producing a porous surface from a solid piece of polymer. In particular, the present disclosure is directed to systems that include a track assembly, mold assembly, press assembly, and methods for using the same for producing a porous surface from a solid piece of polymer. In some embodiments, the present systems and methods are directed to processing a polymer at a temperature below a melting point of the polymer to produce a solid piece of polymer with an integrated a porous surface.

A method for preparing a lithium-ion battery separator is disclosed. The method comprises: cooling and shaping a liquid-phase stabilization system containing polyethylene, stretching to enlarge pores, extracting with a solvent, and heat-setting to obtain a lithium-ion battery separator, wherein the stretching includes pre-stretching and synchronous bidirectional stretching, and the pre-stretching is completed before the synchronous bidirectional stretching.

A composite structure including a metal form. The composite structure further includes an aerogel matrix formed of an aerogel, with the aerogel matrix being nanoporous and including a plurality of aerogel pores. A polymer occupies at least a portion of the aerogel pores of the aerogel matrix. The polymer is a thermoplastic. The thermoplastic is nanoporous and includes a plurality of thermoplastic pores. The thermoplastic pores are less than 10 nanometers in size. The polymer is impregnated within the aerogel pores of the aerogel matrix. The aerogel comprises at least 20% by weight of the composite structure. The aerogel pores are less than 10 nanometers in size. The composite structure further contains filler material. The filler material may be graphene. The composite structure further contains reinforcing agents.

A method of freeze-drying comprising rapidly freezing either liquid or supercritical carbon dioxide in and around a material having pores at a rate of at least 0.2° C./min to limit the size of crystals formed from the carbon dioxide so as to avoid the formation of gas bubbles and damage to the pores and exposure of the material to gas-liquid interfaces. During freezing a solid layer primarily of solid carbon dioxide is formed on and surrounding the material by transferring heat with a cryogenic liquid circulating about the material. This solid layer protects the material from gas-liquid interfaces and surface tension before decreasing pressure about the material by venting carbon dioxide.

An additive manufactured part is formed as a solid body of material including additive manufacturing powder, binder material supporting the powder in the shape of the solid body, and strengthening resin infused within the solid body. The additive manufacturing powder can be sand. The infused resin can be a two-part resin wherein an inert gas is added to the mixture of the two parts of the two-part resin during mixing. The infused resin can be infused inwardly from the peripheral surface of the solid body and can penetrate partially or fully through the thickness of the solid body.

In general, in various embodiments, the present disclosure is directed systems and methods for producing a porous surface from a solid piece of polymer. In particular, the present disclosure is directed to a mold for processing a material. The mold includes a body having a top surface and a bottom surface. A void within the body is configured to receive a porogen and a piece of thermoplastic material. The void extends in a top to bottom direction to form a non-through cavity with a cavity surface that is substantially parallel to the bottom surface of the body. A protrusion on the body extends from the cavity surface towards the top surface. The void extends at least halfway through the body towards the bottom surface. A peg is disposed on the body and shaped to matingly engage a weight via a hole within the weight.