title: Simple model for the deformation-induced relaxation of glassy polymers.
abstract: Glassy polymers show "strain hardening": at constant extensional load, their flow first accelerates, then arrests. Recent experiments have found this to be accompanied by a striking and unexplained dip in the segmental relaxation time. Here we explain such behavior by combining a minimal model of flow-induced liquefaction of a glass with a description of the stress carried by strained polymers, creating a nonfactorable interplay between aging and strain-induced rejuvenation. Under constant load, liquefaction of segmental motion permits strong flow that creates polymer-borne stress. This slows the deformation enough for the segmental modes to revitrify, causing strain hardening.
authors.affiliation: Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom.
authors.forename: S M
authors.initials: SM
authors.lastname: Fielding
authors.forename: R G
authors.initials: RG
authors.lastname: Larson
authors.forename: M E
authors.initials: ME
authors.lastname: Cates