Broad molecular weight distribution polymer product from loop reactors with intentional thermal gradients

A method for producing a polyolefin with a wide molecular weight distribution can comprise: polymerizing one or more monomers in the presence of a catalyst system in a loop reactor to produce a polyolefin product having a polydispersity index of 2.5 to 8, wherein the loop reactor comprises two or more reactors in series, and wherein the loop reactor has a loop thermal gradient of 50° C. to 150° C. and/or a standard deviation of inter-component thermal gradients along the loop reactor of 10° C. to 50° C.