A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) passing the group of flakes through an MRS extruder while maintaining the pressure within the MRS portion of the MRS extruder below about 1.5 millibars; (E) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (F) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) adding one or more color concentrates to the flakes; (E) passing the group of flakes through an extrusion system while maintaining the pressure within the extrusion system below about 25 millibars; (F) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (G) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) adding one or more color concentrates to the flakes; (E) passing the group of flakes through an MRS extruder while maintaining the pressure within the MRS portion of the MRS extruder below about 25 millibars; (F) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (G) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) passing the group of flakes through an MRS extruder while maintaining the pressure within the MRS portion of the MRS extruder below about 1.5 millibars; (E) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (F) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

A method of manufacturing bulked continuous carpet filament from recycled polymer. In various embodiments, the method includes: (1) reducing recycled polymer material into polymer flakes; (2) cleansing the polymer flakes; (3) melting the flakes into a polymer melt; (4) removing water and contaminants from the polymer melt by dividing the polymer melt into a plurality of polymer streams and exposing those streams to pressures below 5 millibars; (5) recombining the streams; and (6) using the resulting purified polymer to produce bulked continuous carpet filament.

A system for manufacturing bulked continuous carpet filament that is adapted for providing a polymer melt and dividing the polymer melt into a plurality of streams (e.g., at least six or eight streams) to increase a surface area of the polymer melt. The plurality of streams is then exposed to a pressure that is below approximately 5 millibars. The streams are then recombined into a single polymer stream and formed into bulked continuous carpet filament. In various embodiments, an extruder, such as a multi-screw extruder, is used to divide the polymer melt into the plurality of streams.

A method for manufacturing bulked continuous carpet filament, the method comprising: (1) reducing a chamber pressure within a chamber to below about 5 millibars; (2) after reducing the chamber pressure to below about 5 millibars, providing a polymer melt to the chamber; (3) separating the polymer melt into at least eight streams; (4) while the at least eight streams of the polymer melt are within the chamber, exposing the at least eight streams of the polymer melt to the chamber pressure of below about 5 millibars; (5) after exposing the at least eight streams of the polymer melt to the chamber pressure of below about 5 millibars, recombining the at least eight streams into a single polymer stream; and (6) forming polymer from the single polymer stream into bulked continuous carpet filament.

A method of manufacturing bulked continuous carpet filament that includes providing a polymer melt and separating the polymer melt from the extruder into at least eight streams. The multiple streams are exposed to a chamber pressure within a chamber that is below approximately 25 millibars, or another predetermined pressure. The streams are recombined into a single polymer stream. Polymer from the polymer stream is then formed into bulked continuous carpet filament.

A carbon fiber bundle is characterized in that a ratio (n/N) of a number n of pairs wherein a flaw of 50 nm in size or more is present on at least one of the fracture surfaces forming the pair to a total number N of pairs of fiber fracture surfaces selected at random after performing a single fiber tensile test for a gauge length of 10 mm is 35% or less, and in that a single-fiber diameter d is 4.3 m or more.

An apparatus for making filaments has a spinneret plate having a row of holes from which emerge filaments. A manifold distributes a supplied plastic melt over a starting spinning width. A filter plate is downstream of the manifold. A pack of distributor plates is downstream of the filter plate. The distributor plates each have a plurality of distributor holes distributed over a manifold width. The distributor holes receive the plastic melt emerging from the filter plate. The spinneret plate is downstream of the distributor-plate pack and has a row of spinneret passages extending over a final spinning width aligned with the spinneret holes. An output face of the filter plate turned toward the distributor-plate pack and/or an inlet face of the spinneret plate turned toward the distributor-plate pack is curved or crowned at least in sections.