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Title: High-pressure crystalline polyethylene studied by x-ray diffraction and ab initio simulations

Abstract

Crystalline polyethylene was investigated under pressure between 0 and 40 GPa, up to 280 deg. C, by means of synchrotron x-ray powder diffraction and ab initio calculations. A rich polymorphism was unveiled, consisting of two new high-pressure monoclinic phases, in addition to the well-known orthorhombic one, which appear reversibly, although with strong hysteresis, upon increasing pressure above 6 GPa (P2{sub 1}/m, Z{sub chain}=1) and 14-16 GPa (A2/m, Z{sub chain}=2), respectively. The equation of state was determined for the three solid phases. We find that polyethylene is characterized by a sharp separation between strong covalent intrachain and weaker interchain interactions up to the maximum investigated pressure, which, in turn, places the ultimate chemical stability limit of polyethylene far beyond these thermodynamic conditions.

Authors:
 [1];  [2]; ;  [1];  [3];  [4];  [1];  [3];  [5]
  1. LENS, European Laboratory for Non-linear Spectroscopy and INFM, Via N. Carrara 1, I-50019 Sesto Fiorentino, Florence (Italy)
  2. International School for Advanced Studies (SISSA), Via Beirut 2-4, 34014 Trieste (Italy)
  3. (Italy)
  4. Abdus Salam International Centre for Theoretical Physics (ICTP) and INFM/Democritos National Simulation Center, 34014 Trieste (Italy)
  5. European Synchrotron Radiation Facility, BP 220, F38043 Grenoble (France)
Publication Date:
OSTI Identifier:
20957827
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.75.174112; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; EQUATIONS OF STATE; HYSTERESIS; MONOCLINIC LATTICES; ORTHORHOMBIC LATTICES; POLYETHYLENES; POWDERS; PRESSURE RANGE GIGA PA; PRESSURE RANGE MEGA PA 10-100; SIMULATION; SOLIDS; SYNCHROTRONS; X-RAY DIFFRACTION

Citation Formats

Fontana, L., Vinh, Diep Q., Santoro, M., Gorelli, F. A., CRS-SOFT-INFM-CNR, c/o Universita di Roma 'La Sapienza', I-00185 Rome, Scandolo, S., Bini, R., Dipartimento di Chimica dell'Universita di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, and Hanfland, M. High-pressure crystalline polyethylene studied by x-ray diffraction and ab initio simulations. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.174112.
Fontana, L., Vinh, Diep Q., Santoro, M., Gorelli, F. A., CRS-SOFT-INFM-CNR, c/o Universita di Roma 'La Sapienza', I-00185 Rome, Scandolo, S., Bini, R., Dipartimento di Chimica dell'Universita di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, & Hanfland, M. High-pressure crystalline polyethylene studied by x-ray diffraction and ab initio simulations. United States. doi:10.1103/PHYSREVB.75.174112.
Fontana, L., Vinh, Diep Q., Santoro, M., Gorelli, F. A., CRS-SOFT-INFM-CNR, c/o Universita di Roma 'La Sapienza', I-00185 Rome, Scandolo, S., Bini, R., Dipartimento di Chimica dell'Universita di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence, and Hanfland, M. Tue . "High-pressure crystalline polyethylene studied by x-ray diffraction and ab initio simulations". United States. doi:10.1103/PHYSREVB.75.174112.
@article{osti_20957827,
title = {High-pressure crystalline polyethylene studied by x-ray diffraction and ab initio simulations},
author = {Fontana, L. and Vinh, Diep Q. and Santoro, M. and Gorelli, F. A. and CRS-SOFT-INFM-CNR, c/o Universita di Roma 'La Sapienza', I-00185 Rome and Scandolo, S. and Bini, R. and Dipartimento di Chimica dell'Universita di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Florence and Hanfland, M.},
abstractNote = {Crystalline polyethylene was investigated under pressure between 0 and 40 GPa, up to 280 deg. C, by means of synchrotron x-ray powder diffraction and ab initio calculations. A rich polymorphism was unveiled, consisting of two new high-pressure monoclinic phases, in addition to the well-known orthorhombic one, which appear reversibly, although with strong hysteresis, upon increasing pressure above 6 GPa (P2{sub 1}/m, Z{sub chain}=1) and 14-16 GPa (A2/m, Z{sub chain}=2), respectively. The equation of state was determined for the three solid phases. We find that polyethylene is characterized by a sharp separation between strong covalent intrachain and weaker interchain interactions up to the maximum investigated pressure, which, in turn, places the ultimate chemical stability limit of polyethylene far beyond these thermodynamic conditions.},
doi = {10.1103/PHYSREVB.75.174112},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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