An intermediary transfer belt having surface resistivity ρs of 1×10.sup.9 Ω/square or more and volume resistivity ρv of 1×10.sup.12 Ω.Math.cm or less includes a thermoplastic resin material containing carbon black. The carbon black contained in the thermoplastic resin material has a weight ratio of 22.5-28.5 weight % and include first carbon black and second carbon black. The first carbon black of the carbon black contained in the thermoplastic resin material has a weight ratio of 50-90 weight % and dibutyl phthalate absorption of 93-127 ml/100 g, and the second carbon black of the carbon black contained in the thermoplastic resin material has a weight ratio of 10-50 weight % and dibutyl phthalate absorption of 36-79 ml/100 g.

A counter-rotating differential speed extrusion device includes a barrel and a screw mechanism in the barrel comprising a first and second screws. A crest diameter and a root diameter of the first screw are respectively meshed with that of the second screw; the first and second screws counter-rotate in differential speeds at a fixed rotation speed ratio; at least one first intermediate circular arc structure with a trend consistent with that of the crest diameter and the root diameter of the first screw is provided between the root diameter and the crest diameter of the first screw, a second intermediate circular arc structure tangent to the first intermediate circular arc structure and having a trend consistent with that of the root diameter and the crest diameter of the second screw is provided between the root diameter and the crest diameter of the second screw.

A counter-rotating differential speed extrusion device includes a barrel and a screw mechanism in the barrel comprising a first and second screws. A crest diameter and a root diameter of the first screw are respectively meshed with that of the second screw; the first and second screws counter-rotate in differential speeds at a fixed rotation speed ratio; at least one first intermediate circular arc structure with a trend consistent with that of the crest diameter and the root diameter of the first screw is provided between the root diameter and the crest diameter of the first screw, a second intermediate circular arc structure tangent to the first intermediate circular arc structure and having a trend consistent with that of the root diameter and the crest diameter of the second screw is provided between the root diameter and the crest diameter of the second screw.

Systems for manufacturing bulked continuous filament having tonal coloring from PET comprise, in various embodiments: (1) an extruder; (2) a static mixing assembly coupled to the extruder comprising: (a) a housing, and (b) one or more individual static mixing elements disposed within the housing; (3) a plurality of colorant ports along a length of the static mixing assembly such that each of the plurality of colorant ports is configured to provide colorant to a polymer stream at a different location along the length of the static mixing assembly; and (4) one or more spinning machines positioned downstream of the static mixing assembly and coupled to the static mixing assembly to receive the colored polymer stream. The spinning machine(s) may be configured to form the colored polymer stream into bulked continuous carpet filament having a tonal color effect.

Systems for manufacturing bulked continuous filament having tonal coloring from PET comprise, in various embodiments: (1) an extruder; (2) a static mixing assembly coupled to the extruder comprising: (a) a housing, and (b) one or more individual static mixing elements disposed within the housing; (3) a plurality of colorant ports along a length of the static mixing assembly such that each of the plurality of colorant ports is configured to provide colorant to a polymer stream at a different location along the length of the static mixing assembly; and (4) one or more spinning machines positioned downstream of the static mixing assembly and coupled to the static mixing assembly to receive the colored polymer stream. The spinning machine(s) may be configured to form the colored polymer stream into bulked continuous carpet filament having a tonal color effect.

Method and system for manufacturing bulked continuous filament having tonal coloring from PET comprising: an extruder (202); a static mixing assembly (208) coupled to the extruder and comprising a housing and one or more individual static mixing elements disposed within the housing; the method and system further comprising a plurality of colorant ports along a length of the static mixing assembly such that each of the plurality of colorant ports is configured to provide colorant (204) to a polymer stream at a different location along the length of the static mixing assembly, and one or more spinning machines (212) positioned downstream of the static mixing assembly and coupled to the static mixing assembly to receive the colored polymer stream. The spinning machine(s) may be configured to form the colored polymer stream into bulked continuous carpet filament having a tonal color effect.

Method and system for manufacturing bulked continuous filament having tonal coloring from PET comprising: an extruder (202); a static mixing assembly (208) coupled to the extruder and comprising a housing and one or more individual static mixing elements disposed within the housing; the method and system further comprising a plurality of colorant ports along a length of the static mixing assembly such that each of the plurality of colorant ports is configured to provide colorant (204) to a polymer stream at a different location along the length of the static mixing assembly, and one or more spinning machines (212) positioned downstream of the static mixing assembly and coupled to the static mixing assembly to receive the colored polymer stream. The spinning machine(s) may be configured to form the colored polymer stream into bulked continuous carpet filament having a tonal color effect.

The disclosure discloses a co-rotating dual speed multi-screw extruder and a processing method thereof, the co-rotating dual speed multi-screw extruder enables a first screw and a second screw with the same outer diameter to co-rotate at different speed in a barrel, and the two screws wipe with each other, to achieve self-cleaning in processing; and circular arcs meshed with each other are respectively arranged between root diameters and top diameters of the two screws to form a first step structure and a second step structure, thus breaking an axial symmetry of a cross-sectional contour of the screws, and moreover, the first step structure and the second step structure are periodically meshed in a meshing zone in a staggered manner, so that a flow channel in the meshing zone is changed in a topological way, a strong elongation action and a strong disturbance action are effectively introduced in the meshing zone.

The disclosure discloses a co-rotating dual speed multi-screw extruder and a processing method thereof, the co-rotating dual speed multi-screw extruder enables a first screw and a second screw with the same outer diameter to co-rotate at different speed in a barrel, and the two screws wipe with each other, to achieve self-cleaning in processing; and circular arcs meshed with each other are respectively arranged between root diameters and top diameters of the two screws to form a first step structure and a second step structure, thus breaking an axial symmetry of a cross-sectional contour of the screws, and moreover, the first step structure and the second step structure are periodically meshed in a meshing zone in a staggered manner, so that a flow channel in the meshing zone is changed in a topological way, a strong elongation action and a strong disturbance action are effectively introduced in the meshing zone.

A method of recycling a PET-containing material comprises: (1) providing an MRS extruder having an MRS section comprising a plurality of satellite screws and an outlet; (2) providing a vacuum pump in communication with the MRS section; (3) providing a spinning machine comprising an inlet, wherein the inlet is directly coupled to the outlet of the MRS extruder; (4) heating a plurality of PET-containing flakes in the MRS extruder to form a PET-containing melt; (5) increasing a surface area of the PET-containing melt by distributing the PET-containing melt across the plurality of satellite screws in the MRS extruder; (6) drawing off vapors from the PET-containing melt by reducing the pressure in the MRS section with the vacuum pump; (7) collating the PET-containing melt in the MRS extruder; and (8) extruding the PET-containing melt through the outlet of the MRS extruder into the inlet of the spinning machine.