B29K2995/004

METHOD FOR CONTROL OF SEMI-CRYSTALLINE THERMOPLASTIC MELT FRONT IN OUT OF AUTOCLAVE PROCESSING
20230150212 · 2023-05-18 · ·

A system and method for thermoplastic composite processing including compressing and heating a thermoplastic composite panel having a plurality of terminal edges. The method further includes heating the thermoplastic composite panel to a melting temperature to create a melt front of the thermoplastic composite panel at a first location and heating the thermoplastic composite panel to the melting temperature in a pre-determined pattern from the first location toward the terminal edges of the thermoplastic composite panel. Extending the melt front toward the terminal edges in this way causes air constrained within the thermoplastic composite panel to escape the thermoplastic composite panel through unmelted portions of the thermoplastic composite panel located between the melt front and the terminal edges. Cooling of the panel may be similarly conducted, cooling a first region and then gradually continuing to cool the panel in a direction toward one or more of the terminal edges.

Heat-stable, biaxially oriented, polypropylene films

In one example embodiment, disclosed is a biaxially oriented multilayer film, which may include a first tie layer and a second tie layer, wherein each has an inside surface and an outside surface. The film's core layer may consist of: (i) at least 50 wt. % high-crystalline polypropylene; (ii) both cyclic olefin copolymer and polypropylene homopolymer, or, polypropylene heterophasic copolymer; (iii) and, optionally, additives, wherein the core layer is between the inside surface of the first tie layer and the inside surface of the second tie layer. The film may also include a first skin layer on the outside surface of the first tie layer and a second skin layer on the outside surface of the second tie layer, wherein shrinkage is less than 3.5% in a transverse direction for the biaxially oriented multilayer film after subjecting the biaxially oriented multilayer film to 135° C. for 7 min at 1 atm.

UNSUPPORTED PART WITH A ROBOTIC ADDITIVE MANUFACTURING SYSTEM
20230382048 · 2023-11-30 ·

A method of printing a hollow part with a robotic additive manufacturing system includes extruding thermoplastic material onto a build platform movable in at least two degrees of freedom in a helical pattern along a continuous 3D tool path with an extruder mounted on a robotic arm, to thereby print a hollow member having a length and a diameter. The method includes orienting the hollow member during printing by moving the build platform based on a geometry of the hollow member wherein the movement of the build platform and the movement of the robotic arm are synchronized to print the part without support structures.

METHOD FOR FORMING THERMOPLASTIC ADDITIVE MANUFACTURING POWDERS

Useful thermoplastic polymer powders are formed by a method comprising: cooling a foam comprised of a thermoplastic foam below the brittleness temperature of the thermoplastic polymer, wherein the foam has an average strut dimension of 10 to 500 micrometers, and comminuting the cooled foam to form a thermoplastic polymer powder. The method allows for the efficient grinding of the thermoplastic polymer having improved morphology and desirable characteristics such as dry flow without flow aids.

POLYKETONE POWDER FOR LASER SINTERING

In one instance a semicrystalline polyketone powder useful for additive manufacturing is comprised of a bimodal melt peak determined by an initial differential scanning calorimetry (DSC) scan at 20° C./min and a D.sub.90 particle size of at most 300 micrometers and average particle size of 1 micrometer to 150 micrometers equivalent spherical diameter. In another instance, A composition is comprised of a semicrystalline polyketone powder having a melt peak and a recrystallization peak, wherein the melt peak and recrystallization peak fail to overlap.

PRODUCTION OF SEMICRYSTALLINE PARTS FROM PSEUDO-AMORPHOUS POLYMERS

A method of manufacturing a semi-crystalline article from at least one pseudo-amorphous polymer including a poly aryl ether ketone, such as PEKK, including a softening step, wherein the at least one pseudo-amorphous polymer is heated to a temperature above its glass transition temperature to soften the polymer, and a crystallization step, wherein the at least one pseudo-amorphous polymer is heated to a temperature between its glass transition temperature and melting temperature, the pseudo-amorphous polymer being placed on a mold during either the softening step or the crystallization step before at least some crystallization takes place. The method results in articles demonstrating increased opacity, increased crystallinity, increased thermal resistance, improved chemical resistance, and improved mechanical properties over articles formed by traditional thermoforming processes.

Production of semicrystalline parts from pseudo-amorphous polymers

A method of manufacturing a semi-crystalline article from at least one pseudo-amorphous polymer including a poly aryl ether ketone, such as PEKK, including a softening step, wherein the at least one pseudo-amorphous polymer is heated to a temperature above its glass transition temperature to soften the polymer, and a crystallization step, wherein the at least one pseudo-amorphous polymer is heated to a temperature between its glass transition temperature and melting temperature, the pseudo-amorphous polymer being placed on a mold during either the softening step or the crystallization step before at least some crystallization takes place. The method results in articles demonstrating increased opacity, increased crystallinity, increased thermal resistance, improved chemical resistance, and improved mechanical properties over articles formed by traditional thermoforming processes.

TRIBOELECTRIC FIBERS, GENERATORS, AND SENSORS
20220255464 · 2022-08-11 ·

Aspects of triboelectric fibers and methods of manufacture of the fibers are described. In one example, a method of manufacture of a fiber for generating energy using the triboelectric effect includes forming a preform tube, heating the preform tube in a furnace, feeding a wire through the preform tube and the furnace during the heating, and pulling the wire through the furnace to form a fiber. The methods described herein can be relied upon to manufacture fibers long enough for industrial-scale textile manufacturing, including for use with industrial-scale looms. In one example, forming the preform tube can include providing a polypropylene tube and wrapping the polypropylene tube with a housing layer of amorphous film, such as acrylic film. The acrylic film can be relied upon to maintain the form and integrity of the polypropylene as the wire is pulled, and the acrylic film can be easily removed after the pulling.

SEMICRYSTALLINE PULVERULENT POLYARYLETHERSULFONES AND METHOD TO MAKE THEM
20220251416 · 2022-08-11 ·

A semicrystalline polyarylethersulfone (PAES) useful for additive manufacturing may be made by a method comprising: dissolving an amorphous polyarylethersulfone in a polar aprotic halogenated hydrocarbon solvent at a temperature adequate to effectively form a solution, and subsequently and spontaneously bring about reprecipitation of a semicrystalline polyarylethersulfone from the solution. The semicrystalline polyarylethersulfone may have a crystallinity of at least 30% by weight. The semicrystalline PAES, upon being heated, melting and uniting together in layers during additive manufacturing cools without substantially recrystallizing, allows for deformation-free articles to be formed having low residual stress.

Method and apparatus for producing a high aspect ratio nanostructured foil by extrusion coating or extrusion casting

A solid nano- or micro-structured thermoplastic foil including a nano- or micro-structured surface area is produced by providing an extrusion casting roller for an industrial polymer extrusion casting process using a thermoplastic material, applying a nano- or micro-structured surface on the extrusion casting roller, maintaining a temperature of the casting roller below a solidification temperature of the thermoplastic material while the casting roller and the counter roller are rotating, and continuously applying a melt of the thermoplastic material between a counter roller and the casting roller while the casting roller and the counter roller are rotating. A rotational velocity of the casting roller may be 10 meters/minute. The melt of the thermoplastic material is moved between the casting roller and the counter roller while the rollers are rolling, and the melt of the thermoplastic material is solidified upon contact with the casting roller to form the thermoplastic foil.