Thermodynamic properties are important in the mixing of liquid materials used in making plastics, said Anthony J. Clark, a UO doctoral student in physics and lead author of the new paper. "Pressure has been a high-level issue in coarse-graining," he said. "It is important to be able to reproduce the distribution of molecules in a system, and pressure is a hard physical quantity to predict. Our theory now will provide the interaction potentials of coarse-grained molecules, which correctly predict both the structure and the thermodynamics of the sample."
The improvements to the formula for the computational simulation mean that manufacturers soon may be able to use a computer code and input information for the materials they plan to mix and quickly determine the behavior of a finished product, said Guenza, a member of the UO's Institute of Theoretical Science, Materials Science Institute and Institute of Molecular Biology.
A problem in working with polymers, for example, is that they often don't blend easily. Controlling for thermodynamic components is vital.
"These molecules are very complex," said co-author Jay McCarty, a doctoral student in chemistry who derived the equations that prove the thermodynamic consistency of Clark's potential and ran the atomistic simulations the test the theory. "They move at different timescales and cover many lengthscales. Our goal is to bridge phenomena that happen at different scales at the molecular level."
Many manufacturing processes rely on often costly, time-consuming and wasteful trial-and-error procedures. While the scientific program is still under development to be extended to a larger number o
|Contact: Jim Barlow|
University of Oregon