Abstract: Polylactide (PLA) parts can be crystallized via two procedures. In the first procedure, i.e. a 2-step post-mold annealing process, the complete crystallization of PLA parts can be done after molding in a secondary operation called as post-mold annealing to make higher heat-resistant PLA parts. There are limitations to this 2-step operation, namely, a) warpage of parts with complex geometries, and b) scaling up higher production volume times. In the second procedure, i.e. 1-step in-mold annealing process, the complete crystallization of PLA parts can be done in the mold itself by holding the temperature of the mold at the crystallization temperature of PLA which is about 100° C. The 1-step in-mold annealing process using a masterbatch blended with neat PLA results in a highly crystalline article produced in a significantly lower cycle time.

Abstract: Carbon fiber and method of forming the same are provided. The method modifies proportion of a finishing oil to control a relation between a surface tension and a particle size of the finishing oil, and thus penetration of the finishing oil into an interior of the carbon fiber is avoided. Therefore, the carbon fiber can have both low oil residues and a high strength.

Abstract: A method for 3D printing a patient-specific bone implant having variable density, in various aspects, comprises: (1) providing a thermoplastic polymer composition comprising: (A) between about 20% and about 50% bioactive agent by weight; (B) between about 0.5% and about 10% chemical foaming agent by weight; and (C) balance structural polymer by weight; (2) receiving, by computing hardware, a scan of a bone, the scan comprising at least a 3D image of the bone and radiodensity data for the bone; and (3) causing, by the computing hardware, a 3D printer to form the patient-specific bone implant from the 3D image using the thermoplastic polymer by modifying a 3D printing temperature of the 3D printer during printing of the patient-specific bone implant such that each portion of the patient-specific bone implant is produced at a temperature that corresponds to a desired density defined by the radiodensity data for the bone.

Abstract: A fabrication method for a filter containing tragacanthin-polyvinyl alcohol (PVA) nanofibers includes obtaining a homogenous tragacanthin-PVA solution by obtaining a PVA solution by dissolving PVA in distilled water, and adding tragacanthin to the PVA solution. The method may further include obtaining a support layer by coating a stainless steel mesh with a thin layer of a hydrophobic polymer, coating a stainless steel mesh with the thin layer of the hydrophobic polymer comprising electrospinning a hydrophobic polymer solution onto the stainless steel mesh, and forming a tragacanthin-PVA nanofibrous web on the support layer by electrospinning the homogenous tragacanthin-PVA solution onto the support layer.

Abstract: According to some aspects, a method is provided of removing debris from a liquid photopolymer in an additive fabrication device. According to some embodiments, a mesh of solid material may be formed in an additive fabrication device from a liquid photopolymer, and particles of debris present in the liquid photopolymer may adhere to the mesh. The debris may thereby be removed from the liquid photopolymer by removing the mesh from the additive fabrication device. The mesh may then be discarded.

Abstract: A system having a first polymer source and a spin beam in fluid communication with the first polymer source is provided. The spin beam includes a spinneret assembly having filament nozzles configured and arranged to extrude a plurality of filaments of a first polymer. A gas distribution plate is disposed downstream of the spinneret assembly, and includes a plurality of gas distribution slots that are configured and arranged to receive two or more corresponding filament nozzles of the spinneret assembly therein. A stream of gas is introduced into the plurality of slots to draw and attenuate the filaments extruded by the plurality of filament nozzles. The drawn and attenuated filaments are collected on a collection surface disposed downstream of the gas distribution plate to form a nonwoven fabric. A solid additive, such as pulp fibers may be blended with the filaments prior to collecting the filaments on the collection surface.

Abstract: A method of enhancing a footwear impression formed on a porous surface using a potassium ferrocyanide solution for footwear impression enhancement includes: forming a porous surface sample by leaving footwear impressions into an object having a porous surface; preparing a potassium ferrocyanide solution for footwear impression enhancement; and applying the potassium ferrocyanide solution for footwear impression enhancement to the porous surface sample.

Abstract: The present invention relates to a suspension comprising 50-95% by weight of the total suspension (w/w) of at least one metallic material and/or ceramic material and/or polymeric material and/or solid carbon containing material; and at least 5% by weight of the total suspension of one or more fatty acids or derivatives thereof. In addition, the invention relates to uses of such suspension in 3D printing processes.

Abstract: The present disclosure discloses a method for preparing a pure chitosan fiber, and relates to the technical field of preparation of chitosan. The method includes the following steps: S1, preparing an acetic acid solution; S2, preparing a chitosan stock solution; S3, treating a chitosan spinning solution; and S4, preparing a chitosan fiber. In step S3, a pretreatment machine includes a body; an driving mechanism is arranged in the body; a stirring mechanism is arranged in the driving mechanism; a scraping mechanism is arranged below the driving mechanism; a preliminary treatment mechanism is arranged at an inner upper side of the body; the driving mechanism penetrates through the preliminary treatment mechanism and is arranged in the body; a separation mechanism is arranged on a bottom of the body.

Abstract: A method of preparing hexagonal boron nitride (h-BN) fibers includes mixing polyvinylpyrrolidone (PVP) and boron oxide (B2O3) to form a polymer precursor or mixing PVP and ammonia borane (BH3NH3) to form the polymer precursor. The method includes forcespinning the polymer precursor to form fibers of the polymer precursor, curing the fibers to form polymer fibers, and pyrolyzing the polymer fibers to form the h-BN fibers.

Abstract: Fibers can include a polypropylene composition, which can include a metallocene random copolymer of propylene and a comonomer that is an alpha-olefin different from propylene. The metallocene random copolymer can have a comonomer content of from 1.2 wt % to 1.8 wt %, a molecular weight distribution of at least 1.0 and of at most 4.0 obtained without thermal or chemical degradation, and a melting temperature Tmelt of at most 140° C. A nonwoven can include the fibers, and a laminate can include the nonwoven. The fibers can be produced by polymerizing the propylene and comonomer in presence of a metallocene-based polymerization catalyst to obtain the metallocene random copolymer. The polypropylene composition can be melt-extruded to obtain a molten polypropylene stream, which can be extruded from capillaries of a spinneret to obtain filaments. A diameter of the filaments can be rapidly reduced to obtain a final diameter.

Abstract: Systems and methods are disclosed for producing multi-layer meltblown mats. The method includes depositing first meltblown fibers onto a first moving surface such as a conveyor belt to form a first layer of meltblown fibers, and depositing second meltblown fibers onto a second moving surface such as a conveyor belt to form a second layer of meltblown fibers. The first and second layers of meltblown fibers are fed through opposed rollers to form combined meltblown layers comprising the first layer of meltblown fibers and the second layer of meltblown fibers. The combined meltblown layers are bonded together to produce a bonded multi-layer meltblown sheet. The bonded multi-layer meltblown sheet has a first outer exposed surface formed by contact of the first layer of meltblown fibers with the first moving surface, and a second outer exposed surface formed by contact of the second layer of meltblown fibers with the second moving surface.

Abstract: A method of forming a three-dimensional object (e.g. comprised of polyurethane, polyurea, or copolymer thereof) is carried out by: (a) providing a carrier and an optically transparent member having a build surface, the carrier and the build surface defining a build region therebetween; (b) filling the build region with a polymerizable liquid, the polymerizable liquid comprising a mixture of: (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from the first component; (c) irradiating the build region with light through the optically transparent member to form a solid blocked polymer scaffold and advancing the carrier away from the build surface to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, the three-dimensional object, with the intermediate containing the second solidifiable component; and then (d) contacting the three-dimensional intermediate to water to form the three-dimensional object.

Abstract: A method for fabricating a porous ceramic heating body, and a method of fabricating a heating body. The method for fabricating includes, in sequence, mixing, ball-milling, defoaming, molding, and drying, pore-forming agent discharging, sintering, and electrode leading. The whole method is simple, and by using a box furnace to sinter the green body under an oxidizing atmosphere and normal pressure, the fabricated ceramic heating body is heated uniformly and the heating efficiency is high.

Abstract: A fully degradable non-woven fabric produced by melt-blown extrusion and an application thereof in the production of medical masks. The fully degradable non-woven fabric is produced through steps of: (S1) preparation of caprolactone-lactic acid random copolymer; (S2) preparation of copolymerized modified PLA; and (S3) preparation of non-woven fabric by the melt-blown extrusion.

Abstract: A method of producing a chemical pulp from a textile material which comprises cellulose for manufacturing regenerated cellulosic molded bodies, wherein in the method the textile material is comminuted, at least a part of non-fiber-constituents of the comminuted textile material is separated from fiber-constituents of the comminuted textile material, at least a part of non-cellulosic fibers of the fiber-constituents is mechanically separated from cellulosic fibers of the fiber-constituents, at least a further part of the non-cellulosic fibers is chemically separated from the cellulosic fibers, and producing regenerated molded bodies from the chemical pulp based on the cellulosic fibers after mechanically separating and chemically separating.

Abstract: A method for manufacturing antibacterial copper nanofiber yarn includes steps of: raw material mixing operation and spinning operation, where the raw material mixing operation is to mix dry copper nanopowder having a particle size of no more than 48 nm with fiber slurry; and the spinning operation includes the following steps: mixing and stirring the copper nanopowder and the fiber slurry so that the copper nanopowder is uniformly distributed in the fiber slurry to prepare a mixed material; drying the mixed material; hot-melt drawing the mixed material, i.e. drawing out yarn with the dried mixed material through a drawing machine to form first-stage yarn; stretching and extending, i.e. passing the first-stage yarn through a plurality of rollers to stretch the first-stage yarn; naturally air-cooling the first-stage yarn to form second-stage yarn; and collecting yarn, i.e. collecting the second-stage yarn to fabricate an antibacterial copper nanofiber yarn finished product.

Abstract: A fabrication method for a water-absorbent filter includes obtaining a homogenized tragacanth suspension by dissolving tragacanth in a solvent, where the solvent may include distilled water, ethyl acetate, acetic acid, and formic acid, obtaining a support layer by coating a stainless steel mesh with a thin layer of a hydrophobic polymer, coating a stainless steel mesh with the thin layer of the hydrophobic polymer comprising electrospinning a hydrophobic polymer solution onto the stainless steel mesh, forming a tragacanth nanofibrous web on the support layer by electrospinning the homogenized tragacanth suspension onto the support layer, and cross-linking the tragacanth nanofibrous web by exposing the tragacanth nanofibrous web to a saturated vapor of a cross-linking agent.

Abstract: A method and apparatus for constructing a tubular assembly 40 comprising an inner portion (24) and a further portion (23) surrounding the inner portion. The inner portion (24) comprises reinforcement (37) and the further portion (23) being formed from a strip (50) of material comprising two opposed longitudinal marginal side portions (53). The apparatus comprises an assembly station (220) comprising a wall (253). The apparatus comprises means for advancing the inner portion (21) along a first path (231) extending passed the wall (253), and means for advancing the strip (50) along a second path (232) and causing the strip to encircle the wall (253) and thereby wrap about and surround the inner portion (21). The apparatus further comprises means (321) for introducing resinous binder into the reinforcement (37) as the strip (50) is being wrapped about the inner portion (21).

Abstract: A printing system for producing at least one three dimensional (3D) printed part is described. The printing system includes a deposition system configured to continuously deposit a layer onto a cylinder to outwardly extend a diameter of the cylinder, wherein the layer comprises a first pattern. The printing system also includes a rotating system configured to rotate the cylinder, and a control system configured to synchronize the deposition system with the cylinder.