Methods for controlling polymer chain scission

A method for controlling polymer chain scission in an extrusion system, comprising:

• melting a polyolefin resin in extruder at a first melt temperature to form a first melt;
• passing the first melt through a screen pack;
• forming the first melt into a first polyolefin product;
• melting additional polyolefin resin of the same grade in the extruder at a second melt temperature to form a second melt, wherein the second melt temperature differs from the first melt temperature by 5° C. or more to control chain scission in the extruder;
• passing the second melt through the screen pack;
• and
• forming the second melt into a second polyolefin product, wherein the screen pack comprises a plurality of screens arranged in series, wherein the screens comprise an inlet screen having a size from 20 mesh to 80 mesh, two or more intermediate screens having a size of 100 mesh or greater, and an outlet screen having a size from 20 mesh to 80 mesh, wherein a throughput channel in the screen pack has a cross sectional area of at least 344 cm2.