Abstract: Die plates for polymer extrusion may include a die plate having an entrance face for accepting a polymer flow and an exit face for extruding one or more polymer strands, wherein the exit face including at least one element constructed from polycrystalline diamond. Systems for extruding polymer may include: an extruder, a die plate attached to an outlet of the extruder and having (i) an entrance face for accepting a polymer flow and (ii) an exit face for extruding one or more polymer strands; an array of blades configured to rotate so as to contact and slide along the surface of the die exit face, thereby cutting the one or more polymer strands extruded therethrough; wherein (a) the exit face, (b) the blade array, or (c) each of the exit face and the blade array comprises at least one element constructed from polycrystalline diamond.

Abstract: Methods and compositions for processing polymers with fluorine-free polymer processing aids (PPAs) are described. The methods can include continuously extruding a polymer composition through an extruder to form a polymer product, and during at least a portion of the extruding, continually feeding a polyethylene glycol (PEG) composite to the extruder so that the PEG composite and polymer composition are coextruded through the extruder at conditions sufficient to melt blend the PEG composite and the polymer composition. The PEG composite can comprise or consist essentially of PEG (preferably PEG having weight average molecular weight less than 10,000 g/mol) and one or more non-PPA additives having melting point at 1 atm greater than that of the PEG.

Abstract: Methods and compositions for processing polymers with fluorine-free polymer processing aids (PPAs) are described. The methods can include continuously extruding a polymer composition through an extruder to form a polymer product, and during at least a portion of the extruding, continually feeding a polyethylene glycol (PEG) composite to the extruder so that the PEG composite and polymer composition are coextruded through the extruder at conditions sufficient to melt blend the PEG composite and the polymer composition. The PEG composite can comprise or consist essentially of PEG (preferably PEG having weight average molecular weight less than 10,000 g/mol) and one or polymers having melting point at 1 atm greater than that of the PEG.

Abstract: Methods for cleaning a die face for an extruder include: positioning an articulating tool adjacent the die face while the die face is installed on the extruder, the die face defining a plurality of die orifices; triggering operation of the articulating tool and thereby articulating an end effector coupled to the articulating tool; and contacting the end effector against one or more surfaces of the die face and thereby removing fouling from the die plate. Methods may include: pausing production of a polymer pellet product from the extruder when at least one of the pressure at the die or a polymer pellet product properties indicates fouling at the die; removing a polymer residue from one or more orifices in the die with an articulating tool equipped with an end effector while the die is mounted on the extruder; and resuming production of the polymer pellet product.