Solid-State NMR Investigation of the Structural Consequences of Plastic Deformation in Polycarbonate. 1. Global Orientational Order

Abstract

The global orientational order that develops in polycarbonate under plastic deformation has been measured quantitatively by CSA and dipolar DECODER experiments. The results are in substantial agreement with the predictions of an affine entanglement network model. Athermal atomistic simulations, on the other hand, tend to overestimate the orientational order. The orientation behavior in glassy polycarbonate seems to be essentially the same as that in the melt.

Molecular response of a glassy polymer to active deformation

“…4. This agrees well with NMR data from Utz et al [35] which indicate that the distribution of dihedral angle conformations does not change significantly after deformation up to strains as large as 0.68.…”

Non-linear, rate-dependent strain-hardening behavior of polymer glasses

“…(18). The validity of the concept of a network active during plastic deformation in glassy polymers as a generator for strain-hardening and especially segmental orientation is supported by solid-state NMR studies on segmental orientational order in deformed poly(bisphenol A carbonate) [31] and poly(methylmethacrylate) [32,33]. This network is of considerably higher density than the entanglement network.…”

Determination of Orientational Order in Deformed Glassy PMMA from Solid-State NMR Data

“…Furthermore, there are strong indications that certain structural units in polymer glasses, e.g. stiff chain segment, orient under plastic deformation according either to the so-called affine 12,39 or to the pseudo-affine model. 9,39,40,66,67 Hence initial simulation tests were performed with different single-peaked input ODFs according to the affine and pseudo-affine model.…”