(13i) Prediction of Self-Diffusion Coefficients of Polymer Melts Using Modified Free Volume Theory and MD Simulation
AIChE Annual Meeting
2019
2019 AIChE Annual Meeting
Materials Engineering and Sciences Division
Atomistic and Molecular Modeling and Simulation of Polymers
Sunday, November 10, 2019 - 5:45pm to 6:00pm
MD simulation of polyethylene melts with different chain lengths is performed. Crossover in the center-of-mass self-diffusion coefficient (D) as a function of chain length (N) is observed: as N<Nc, D~N-1 and as N>Nc, D~N-2.2. The modified free volume theory is used to describe such crossover as observed in the MD simulation. The two parameters in the modified free volume theory, which are the critical free volume and mean free volume per repeat unit, can be determined from the pair correlation function by either solving PRISM equations for polymers or using the MD simulation data. This makes the modified free volume theory parameter-free. Voronoi tessellation of the MD simulation data are also performed for comparison with the statistical mechanical calculations. Such analysis gives us the exact distribution of free volume in the polymer melts, and therefore the probability for a repeat unit having free volume greater than that of critical free volume.
Checkout
This paper has an Extended Abstract file available; you must purchase the conference proceedings to access it.
Do you already own this?
Log In for instructions on accessing this content.
Pricing
Individuals
AIChE Pro Members | $150.00 |
AIChE Graduate Student Members | Free |
AIChE Undergraduate Student Members | Free |
AIChE Explorer Members | $225.00 |
Non-Members | $225.00 |