AN APPROXIMATION METHOD FOR SIMULATING TEMPERATURE DEPENDENCE OF POISSON’S RATIOS OF SELF-EXPANDING AUXEGENS
Wu Hongmei *, Wei Gaoyuan **
Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering Peking University, Beijing 100871, People’s Republic of China
Received:
Rec. 13 December 2004
DOI: 10.12921/cmst.2004.10.02.229-234
OAI: oai:lib.psnc.pl:574
Abstract:
A combined molecular dynamics and molecular mechanics method has been developed for estimating Poisson’s ratios of certain types of molecular auxetics at various temperatures. The temperature dependence of the auxeticity of a special class of molecular auxetics, namely, a self-expanding supramolecular network of auxegens containing alternating phenyl and acetylene links, is studied with use of this approximation method. The simulation results show that as temperature increases from 0 to 300 K, the auxeticity of the resulting superlattice or van der Waals network of auxegens decreases from the initial self-expandability to two negatively small Poisson ratios on the xoy plane.
Key words:
auxegen, auxeticity, auxetics, Poisson ratio, polymers, self-organized systems, superlattices
References:
[1] K. E. Evans and A. Alderson, Adv. Mater. 12, 617 (2000).
[2] G. Y. Wei, Mater. Rev. (in Chinese) 17, 8 (2003).
[3] K. W. Wojciechowski, Mol. Phys. 61, 1247 (1987).
[4] K. W. Wojciechowski, Phys. Lett. A 137, 60 (1989).
[5] K. W. Wojciechowski, K. V. Tretiakov, and M. Kowalik, Phys. Rev. E 67, 036121 (2003).
[6] K. E. Evans, M. A. Nkansah, I. J. Hutchinson, and S. C. Rogers, Nature 353, 124 (1991).
[7] G. Y. Wei, S. F. Edwards, I. J. Hutchinson, W. C. Mackrodt, S. C. Rogers, and K E. Evans, Research Report No. I C 15657 (ICI Chemicals and Polymers, Runcorn, UK) on A Feasibility Study on the Chemical Synthesis of ‘Auxetic’ Materials – A Novel Class of Molecular Networks with -ve Poisson Ratios, 2 September 1991. G. Y. Wei, S. F. Edwards, Research Proposal to ICI Chemicals and Polymers (Runcorn, UK) – Synthesis ofNegative-Poisson-Ratio Molecular Networks, 8 November 1990.
[8] K. E. Evans, A. Alderson, and F. R. Christian, J. Chem. Soc. Faraday Trans. 91, 2671 (1995).
[9] J. N. Grima and K. E. Evans, Chem. Commun. 1531 (2000).
[10] G. Y. Wei, Phys. Stat. Sol. B (in press).
[11] H. M. Wu and G. Y. Wei, Acta Polvm. Sinica (2), 198 (2004).
[12] H. M. Wu and G. Y. Wei, Chin. J. Polym. Sci. 22(4), 355 (2004).
[13] J. H. Weiner, Statistical Mechanics of Elasticity, John Wiley: New York (1983).
[14] M. Parrinello and A. Rahman, J. Chem. Phys. 76, 2662 (1982).
[15] A. A. Gusev, M. M. Zehnder, U. W. Suter, Phys. Rev. Rep. B 54, 1 (1996).
[16] Cerius24.0 User Guide, Property Prediction, Molecular Simulations Inc., San Diego (1999).
A combined molecular dynamics and molecular mechanics method has been developed for estimating Poisson’s ratios of certain types of molecular auxetics at various temperatures. The temperature dependence of the auxeticity of a special class of molecular auxetics, namely, a self-expanding supramolecular network of auxegens containing alternating phenyl and acetylene links, is studied with use of this approximation method. The simulation results show that as temperature increases from 0 to 300 K, the auxeticity of the resulting superlattice or van der Waals network of auxegens decreases from the initial self-expandability to two negatively small Poisson ratios on the xoy plane.
Key words:
auxegen, auxeticity, auxetics, Poisson ratio, polymers, self-organized systems, superlattices
References:
[1] K. E. Evans and A. Alderson, Adv. Mater. 12, 617 (2000).
[2] G. Y. Wei, Mater. Rev. (in Chinese) 17, 8 (2003).
[3] K. W. Wojciechowski, Mol. Phys. 61, 1247 (1987).
[4] K. W. Wojciechowski, Phys. Lett. A 137, 60 (1989).
[5] K. W. Wojciechowski, K. V. Tretiakov, and M. Kowalik, Phys. Rev. E 67, 036121 (2003).
[6] K. E. Evans, M. A. Nkansah, I. J. Hutchinson, and S. C. Rogers, Nature 353, 124 (1991).
[7] G. Y. Wei, S. F. Edwards, I. J. Hutchinson, W. C. Mackrodt, S. C. Rogers, and K E. Evans, Research Report No. I C 15657 (ICI Chemicals and Polymers, Runcorn, UK) on A Feasibility Study on the Chemical Synthesis of ‘Auxetic’ Materials – A Novel Class of Molecular Networks with -ve Poisson Ratios, 2 September 1991. G. Y. Wei, S. F. Edwards, Research Proposal to ICI Chemicals and Polymers (Runcorn, UK) – Synthesis ofNegative-Poisson-Ratio Molecular Networks, 8 November 1990.
[8] K. E. Evans, A. Alderson, and F. R. Christian, J. Chem. Soc. Faraday Trans. 91, 2671 (1995).
[9] J. N. Grima and K. E. Evans, Chem. Commun. 1531 (2000).
[10] G. Y. Wei, Phys. Stat. Sol. B (in press).
[11] H. M. Wu and G. Y. Wei, Acta Polvm. Sinica (2), 198 (2004).
[12] H. M. Wu and G. Y. Wei, Chin. J. Polym. Sci. 22(4), 355 (2004).
[13] J. H. Weiner, Statistical Mechanics of Elasticity, John Wiley: New York (1983).
[14] M. Parrinello and A. Rahman, J. Chem. Phys. 76, 2662 (1982).
[15] A. A. Gusev, M. M. Zehnder, U. W. Suter, Phys. Rev. Rep. B 54, 1 (1996).
[16] Cerius24.0 User Guide, Property Prediction, Molecular Simulations Inc., San Diego (1999).
