Alumnus
Brian J. Banaszak

Education

• Sc.B., Chemical Engineering, Massachusetts Institute of Technology, 1997
• M.Sc., Chemical Engineering Practice, Massachusetts Institute of Technology, 1998
• Ph.D., Chemical and Biological Engineering, University of Wisconsin-Madison, 2004

Research

In order to understand the kinetics of polymerization processes, and hence, the quality of polymer product, it is essential to have precise knowledge of the thermodynamics of such systems. Available equation of states for polymer mixtures are usually semi-empirical to agree with experimental data, and hence, not very predictive.

In our research, we are studying phase equilibria of polyolefin / reactant mixtures via molecular simulations. In particular we are interested in the phase equilibria behavior at polyolefin reaction conditions. We use a continuous united atom force field (NERD force field) to describe the interactions between the hydrocarbons in a polyolefin reaction mixture. Simulations involving polymers are very time intensive. Therefore, much of our research involves improving the efficiency of simulations for chain molecules. Our simulations have proved to be in excellent agreement with available experimental data.

In many reaction conditions, polyolefins are below their melting temperature, and hence, in a semi-crystalline state. The crystallites in these polyolefins inhibit swelling in the amorphous phases of the polyolefin mixture. In other words, the solubilities of reactants in the amorphous polyolefin is reduced due to the crystallites. Our simulations are only capable of simulating a hypothetically amorphous polyolefin at these conditions. Simulations of the semi-crystalline states is not possible for a detailed simulation model. So, in conjunction with simulations, we are developing an equation of state to correct for the phase behavior of polyolefin mixtures due to swelling in polyolefins. In this equation of state, we are developing a model to accurately predict the phase behaviour of the purely amorphous mixture as predicted from simulations and then use Flory-Rehner theory to describe the effect of crystallites on the solubility of reactants in polyolefins.

Publications

• Brian J. Banaszak, Roland Faller, and Juan J. de Pablo.
  "Simulation of the effects of chain architecture on the sorption of ethylene in polyethylene".
  Journal of Chemical Physics 120(23):11304-11315, 2004 June 15. [DOI] [AIP/JCP]
• Brian J. Banaszak and Juan J. de Pablo.
  "A new double-rebridging technique for linear polyethylene".
  Journal of Chemical Physics 119(4) 2456--2462, 2003 July 22. [DOI] [AIP/JCP]
• Shyamal K. Nath, Brian J. Banaszak, and Juan J. de Pablo.
  "A new united atom force field for alpha-olefins".
  Journal of Chemical Physics 114(8):3612-3616, February 22, 2001. [doi:10.1063/1.1343487] [AIP/JCP]
• Shyamal K. Nath, Brian J. Banaszak, and Juan J. de Pablo.
  "Simulation of ternary mixtures of ethylene, 1-hexene, and polyethylene".
  Macromolecules 34(22):7841-7848, September 19, 2001. [doi:10.1021/ma002197l] [ACS/MA]

Contact

Mr. Brian J. Banaszak
BASF Aktiengesellschaft
Ludwigshafen, Germany