Determination of rotary diffusivity of poly(n-propyI isocyanate)

摘要

The rotational dynamics of a nondilute solution of the rodlike polymer poly(n-propyl isocyanate) (PPIC) has been studied on an atomistic model by means of a large-scale classical molecular dynamics investigation.The rotary diffusivity of PPIC in toluene solution has been determined from the Einsteinian diffusion regime of the end-to-end vector on the surface of the unit sphere and has been found to be D_r=10.5 X 10~5(+-2.7) s~(-1),which falls in the range of the experimental data available.A comparison of molecular dynamics predictions with theoretical and perturbation expansion predictions has also been performed.