کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1315390 976023 2006 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Estimation and analysis of the rheological properties of a perfluoropolyether through molecular dynamics simulation
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Estimation and analysis of the rheological properties of a perfluoropolyether through molecular dynamics simulation
چکیده انگلیسی

Equilibrium and non-equilibrium molecular dynamics simulations of a perfluoropolyether C8F18O4 are reported using an atomistic interaction potential. The bulk rheological properties of the perfluoropolyether are investigated through molecular dynamics simulations as a function of both temperature and shear rate. The effect of molecular structure on viscosity is explored in detail. The rotational relaxation time is reported as a function of temperature. Structural properties, including the mean-square end-to-end chain length, the mean-square radius of gyration of chains, and the distribution functions of bond lengths, bond angles, and bond torsional angles are collected and analyzed as functions of shear rate. After an initial plateau, both mean-square end-to-end chain length and mean-square radius of gyration decrease monotonically with increasing shear rate. The behaviors of the rheological and structural properties are explained through an analysis of the individual contributions due to bond stretching, bond bending, and bond torsion, as well as both intramolecular and intermolecular non-bonded interactions. A further analysis is possible through a meticulous breakdown of each contribution into a specific type of mode; e.g., the total bond stretching is comprised of CC, CO, and CF bond stretching terms. In this way, one can relate the shear viscosity to the specific chemical structure of C8F18O4.

The molecular structure of a single molecule C8F18O4. Oxygen atoms are black, carbon atoms are white, and fluorine atoms are gray. Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Fluorine Chemistry - Volume 127, Issue 6, June 2006, Pages 787–795
نویسندگان
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