| Coarse-Grained and Atomistic Modeling of Polyimides Contributor(s): Clancy, Thomas C. (Author), Hinkley, Jeffrey a. (Author), Nasa Technical Reports Server (Ntrs) (Created by) |
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ISBN: 1287264824 ISBN-13: 9781287264828 Publisher: Bibliogov OUR PRICE: $14.96 Product Type: Paperback Published: July 2013 |
| Additional Information |
| BISAC Categories: - Political Science |
| Physical Information: 0.07" H x 7.44" W x 9.69" (0.18 lbs) 34 pages |
| Descriptions, Reviews, Etc. |
| Publisher Description: A coarse-grained model for a set of three polyimide isomers is developed. Each polyimide is comprised of BPDA (3,3,4,4' - biphenyltetracarboxylic dianhydride) and one of three APB isomers: 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene or 1,3-bis(3-aminophenoxy)benzene. The coarse-grained model is constructed as a series of linked vectors following the contour of the polymer backbone. Beads located at the midpoint of each vector define centers for long range interaction energy between monomer subunits. A bulk simulation of each coarse-grained polyimide model is performed with a dynamic Monte Carlo procedure. These coarsegrained models are then reverse-mapped to fully atomistic models. The coarse-grained models show the expected trends in decreasing chain dimensions with increasing meta linkage in the APB section of the repeat unit, although these differences were minor due to the relatively short chains simulated here. Considerable differences are seen among the dynamic Monte Carlo properties of the three polyimide isomers. Decreasing relaxation times are seen with increasing meta linkage in the APB section of the repeat unit. |