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).

A method for controlling polymer viscosity quality in a compounding process of polymers (110) using at least one extruder (111) is disclosed. The method comprises: a) at least one measurement step (112), wherein at least one influence variable affecting viscosity of the compound is determined by using at least one sensor (114); b) at least one prediction step (116), wherein an expected viscosity (117) of the compound is determined considering the influence variable by using at least one prediction unit (118), wherein the prediction unit (118) comprises at least one analysis tool comprising at least one trained model; c) at least one evaluation step (120), wherein the expected viscosity (117) of the compound is compared to at least one pre-defined and/or pre-determined threshold value, wherein at least one item of output information is generated depending on said comparison; and d) at least one control step (122), wherein the item of output information is displayed using at least one display device (124), wherein the output information comprises at least one handling recommendation (126) for at least one setting of the extruder (111). Further disclosed are a computer program, specifically an application, and a controlling system (138) for controlling polymer viscosity quality in a compounding process of polymers (110).

A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.

The present disclosure provides processes for producing polyethylene resins. In at least one embodiment, a polyethylene has: a density of from about 0.91 g/cm.sup.3 to about 0.94 g/cm.sup.3; a value of Mz of about 1,500,000 g/mol or greater; and a ratio of Mz to Mw of about 7 or greater. A process includes introducing a first feed stream having ethylene monomer and a first free radical initiator to a first inlet of a first reaction zone, where the first reaction zone has a first inlet temperature. The process further includes introducing a second feed stream having ethylene monomer and a second free radical initiator to a second inlet of a second reaction zone, where the second reaction zone has a second inlet temperature that is the same or different than the first inlet temperature.

The invention provides a coextrusion feedblock having a flow adjuster, a viscosity compensation device, an actuator, a central extrusion conduit, and a coextrusion conduit. The invention also provides a coextrusion profiling insert assembly constructed to be mounted in a coextrusion feedblock. The insert assembly has a flow adjuster, a viscosity compensation device, and an actuator. The insert assembly when mounted in the feedblock has a coextrusion conduit extending between the flow adjuster and the viscosity compensation device. The actuator is adjustable to apply force to bend the viscosity compensation device and thereby adjust a gap height of the coextrusion conduit. Also provided is a method of operating a feedblock having a viscosity compensation device comprising a flex region, a central extrusion conduit, and a coextrusion conduit. Force is applied to bend the flex region of the viscosity compensation device and thereby adjust a gap height of the coextrusion conduit.

Techniques recycle plastics in multiple successive process steps. A polymer, preferably a recyclable material, is melted using a discharge extruder, filtered using a first filter device under a positive pressure atmosphere, filtered and degassed using a degassing device, and discharged using a discharge extruder. The degassing device has at least one filter element and a vacuum chamber with a negative pressure atmosphere for filtering and degassing purposes, wherein the plastic melt can be conducted into the negative pressure atmosphere of the vacuum chamber through the filter element.

A method for manufacturing a prosthetic component include injection molding a prosthetic component with a polymeric material. The prosthetic component includes a final surface positioned on one side and multiple coring features positioned on an opposite side. The coring features may include multiple ribs and slots. The method further includes machining the prosthetic component to remove the coring features and form a final surface on the opposite side. The prosthetic component may be a femoral component for a prosthetic knee joint.

Methods for recycling plastic Nylon 6,6 from vacuum bags to obtain filaments or powder for 3D printing processes. The method to obtain filaments includes a step of providing used Nylon 6,6 vacuum bags, a quality control step to check the status of the used vacuum bags, a step to form smaller parts, such as smaller pieces or pellets, from the used vacuum bags, quality control step to check the status of the smaller pieces or the pellets, an extrusion step wherein the smaller pieces or the pellets are introduced into an extruder, where they are melted, and the molten mixture is cooled and expelled through the die of the extruder to produce the recycled filaments, and a winding step wherein the recycled filaments that go out of the extruder are rolled up in coils.

A production method for a low molecular weight polymer suitable for a melt-blown non-woven fabric and a production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage arranged in the axial direction inside the screw body.