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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 32: P4: Computational Physics of Soft Matter
CPP 32.1: Poster
Dienstag, 17. März 2015, 14:00–16:00, Poster B
New insights into the structure of poly(p-phenylene terephthalamide: a first principles study — •Pegah Zolfaghari1, Ole Braukamann1, Arno P M Kentgens1, Robert A de Groot1,2, and Gilles A de Wijs1 — 1Radboud university Nijmegen, Electronic Structure of Materials,Institute for Molecules and Materials, Netherlands — 2Rijksuniversiteit Groningen, Solid State Materials for Electronics,Zernike Institute for Advanced Materials, Netherlands
The aromatic polyamids are a major class of polymers in recet years.This class of polyamids are of practical interest due to their high tensile strength, high elastic modulus, low elongation at breakage, and higher thermomechanical stability among other kinds of polyamids.
One of the interesting member of this class of fibres called poly, p-phenylene terepthalamide (hereafter PPTA). PPTA is a polymer which crystalizes in the form of 2D hydrogen-bonded sheets. It has enormous commerical applications, as already mentioned, and is sold under the commercial names of Kevlar and Twaron. The packing of the hydrogen-bonded sheets and phenyl group give rise to three different PPTA structures, including Northolt, Liu and Pb.
The calculations reveal that different PPTA structures which all exhibit herringbone packing of the phenyl groups between neighboring sheets, have similar stabilities. Also, The use of solid-state NMR experiments combined with Density Functional Theory (DFT) based calculations allows unambiguous assignment of all proton and carbon resonances of PPTA structures.