Methods for extrusion of polyolefins (112 ) that control specific energy input to the extruder (102 ) for gel reduction. Disclosed herein is an example method for forming plastic products (120, 208 ) with reduced gels, comprising: melting a polyolefin resin (112 ) in extruder (102 ) to form a melt; adjusting specific energy input in the extruder (102 ) to reduce gels in the melt; and forming the melt into a polyolefin product (120, 208 ). Disclosed herein is also an example method for forming plastic products (120, 20 ) with reduced gels, comprising: melting a polyolefin resin in extruder (102 ) to form a melt; selecting a throttle valve (104 ) position for gel reduction; setting the throttle valve (104 ) at the selected throttle valve (104 ) position to restrict flow of the melt out of the extruder (102 ); and forming the melt into a polyolefin product (120, 208 ).

Methods for extrusion of polyolefins (110) that utilize melt temperature to control molecular weight and also reduce gels. Disclosed herein is an example method for controlling polymer chain scission in an extrusion system (100), comprising: melting a polyolefin resin (110) in extruder (102) at a first melt temperature to form a first melt (112); passing the first melt (112) through a screen pack (106); forming the first melt 112) into a first polyolefin product (116, 118); melting additional polyolefin resin (110) of the same grade in the extruder (102) at a second melt temperature to form a second melt (112), wherein the second melt temperature differs from the first melt temperature by 5° C. or more to control chain scission in the extruder (102); passing the second melt (112) through the screen pack (106); and forming the second melt (112) into a second polyolefin product (116, 118).

An extruder is provided with: a screw rotationally driven about the axis by a first motor; a barrel having a screw hole into which the screw is inserted and a de-airing port configured to discharge air inside the screw hole; a filter configured such that a part thereof faces the de-airing port of the barrel; and a filter-driving mechanism configured to move the filter to shift the part of the filter facing the de-airing port.

The present invention relates to a method for preparing thermoplastic polymer particles, the method comprising the steps of: (1) extruding a thermoplastic polymer resin by means of an extruder; (2) granulating the extruded polymer resin by using an inert gas; and (3) cooling the granulated thermoplastic polymer resin, and thermoplastic polymer particles prepared thereby.

There are provided a straining mechanism and a screw extruder including the straining mechanism, which can minimize material passing resistance in a breaker plate even, in a large-sized apparatus having high throughput, and which can improve the throughput by suppressing load power of the apparatus and heat generation of a material. For this purpose, a backup plate having an opening rate higher than an opening rate of a breaker plate and supporting the breaker plate is installed on a rear surface side of the breaker plate supporting a screen mesh.

There are provided a straining mechanism and a screw extruder including the straining mechanism, which can minimize material passing resistance in a breaker plate even, in a large-sized apparatus having high throughput, and which can improve the throughput by suppressing load power of the apparatus and heat generation of a material. For this purpose, a backup plate having an opening rate higher than an opening rate of a breaker plate and supporting the breaker plate is installed on a rear surface side of the breaker plate supporting a screen mesh.

The present invention relates to a method for manufacturing thermoplastic polymer particles, and the thermoplastic polymer particles, the method comprising the steps of: (1) extruding a thermoplastic polymer resin through an extruder; (2) spraying the extruded thermoplastic polymer resin through a nozzle and then spraying a gas to the sprayed thermoplastic polymer resin through a plurality of sprayers so as to granulate same; and (3) cooling the granulated thermoplastic polymer resin.

Provided are a polyester white film and a back sheet for a solar cell module using the same, and in particular, provided is a polyester white film having improved light reflectance.

A method of recycling a PET-containing material comprises: (1) providing a polymer crystallizer comprising at least one heating element, and at least one blower; (2) providing an MRS extruder having an MRS section comprising a plurality of satellite screws; (3) providing a vacuum pump in fluid communication with the MRS section; (4) grinding and washing the PET-containing material; (5) heating the PET-containing material in the crystallizer to at least partially dry the PET-containing material; (6) shearing the PET-containing material in the MRS extruder to produce a PET-containing melt; (7) increasing a surface area of the PET-containing melt by distributing the PET-containing melt across a plurality of satellite screws in the MRS extruder; (8) drawing off vapors from the PET-containing melt by reducing the pressure in the MRS section with the vacuum pump; (9) collating the PET-containing melt in the MRS extruder; and (10) extruding a recycled PET-containing material.

A method of recycling a PET-containing material comprises: (1) providing a polymer crystallizer comprising at least one heating element, and at least one blower; (2) providing an MRS extruder having an MRS section comprising a plurality of satellite screws; (3) providing a vacuum pump in fluid communication with the MRS section; (4) grinding and washing the PET-containing material; (5) heating the PET-containing material in the crystallizer to at least partially dry the PET-containing material; (6) shearing the PET-containing material in the MRS extruder to produce a PET-containing melt; (7) increasing a surface area of the PET-containing melt by distributing the PET-containing melt across a plurality of satellite screws in the MRS extruder; (8) drawing off vapors from the PET-containing melt by reducing the pressure in the MRS section with the vacuum pump; (9) collating the PET-containing melt in the MRS extruder; and (10) extruding a recycled PET-containing material.