Osmotic pressure and virial coefficients of star and comb polymer solutions: Dissipative particle dynamics

NCUIR > Engineering College > National Central University Department of Chemical & Materials Engineering > journal & Dissertation > Item 987654321/26411

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/26411

Title:	Osmotic pressure and virial coefficients of star and comb polymer solutions: Dissipative particle dynamics
Authors:	Wang,TY;Fang,CM;Sheng,YJ;Tsao,HK
Contributors:	化學工程與材料工程學系
Keywords:	MONTE-CARLO;CROSSOVER-BEHAVIOR;BRANCHED POLYMERS;GOOD SOLVENTS;2ND;DILUTE;RENORMALIZATION;POLYSTYRENES;BENZENE;4-ARM
Date:	2009
Issue Date:	2010-06-29 17:27:26 (UTC+8)
Publisher:	中央大學
Abstract:	The effects of macromolecular architecture on the osmotic pressure pi and virial coefficients (B-2 and B-3) of star and comb polymers in good solvents are studied by dissipative particle dynamics simulations for both dilute and semiconcentrated regimes. The dependence of the osmotic pressure on polymer concentration is directly calculated by considering two reservoirs separated by a semipermeable, fictitious membrane. Our simulation results show that the ratios A(n+1) equivalent to Bn+ 1/(R) over cap (3n)(g) are essentially constant and A(2) and A(3) are arm number (f) dependent, where (R) over cap (g) is zero-density radius of gyration. The value of dimensionless virial ratio g=A(3)/A(2)(2) increases with arm number of stars whereas it is essentially arm number independent for comb polymers. In semiconcentrated regime the scaling relation between osmotic pressure and volume fraction, pi(proportional to)phi(lambda), still holds for both star and comb polymers. For comb polymers, the exponent lambda is close to lambda* (approximate to 2.73 for linear chains) and is independent of the arm number. However, for star polymers, the exponent lambda deviates from lambda* and actually grows with increasing the arm number. This may be attributed to the significant ternary interactions near the star core in the many-arm systems. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3099721]
Relation:	JOURNAL OF CHEMICAL PHYSICS
Appears in Collections:	[National Central University Department of Chemical & Materials Engineering] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	693	View/Open

社群 sharing

Loading...