Chain elastic modulus of polyethylene: A spectroscopically determined force field (SDFF) study
✍ Scribed by Kim Palmö; Samuel Krimm
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 713 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0887-6266
No coin nor oath required. For personal study only.
✦ Synopsis
Our SDFF for linear saturated hydrocarbon chains has been used to calculate the chain modulus of isolated and crystalline chains of n-alkanes of varying lengths. This has been done for static deformations and for the dynamic deformation in the longitudinal acoustic mode (LAM). Extrapolation to infinite chain length gives a common value of the room-temperature crystal modulus of 303 GPa (also obtained in an infinite chain calculation). Experimental Raman LAM measurements, corrected for chain-end interactions, give a modulus of 305 GPa, in excellent agreement. Problems with the experimental values obtained by inelastic neutron scattering and x-ray diffraction are discussed.