Quasi-Static Modeling of Chain-Dynamics in the Amorphous Glassy Polycarbonate of 4,4'-Isopropyledenediphenol
Interim technical rept. no. 31, 1990-1991,
MASSACHUSETTS INST OF TECH CAMBRIDGE
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A detailed static atomistic model of the defense, glassy polycarbonate of 4,4-isopropylidenediphenol bisphenol-A polycarbonate, PC is used for a quasi-static simulation of localized motions. These motions include the phenylene ring flip, conformational changes of the carbonate group, and cooperative main chain motion. The frequency distributions for both simulated motions cover several orders of magnitude. The average energy barrier to phenylene ring flip is calculated as 10.4 kcalmol. No significant reorientation of the ring axis was observed in the simulations, with 90 of the axes changing less than 15. A slight main chain motion was found superimposed upon the ring flip and the carbonate group conformational changes.