Article

Complete mapping of the morphologies of some linear and graft fluorinated co-oligomers in an aprotic solvent by dissipative particle dynamics.

Materials Science and Engineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Orhanli, Tuzla, Istanbul, Turkey.
The Journal of Chemical Physics (impact factor: 3.33). 03/2006; 124(6):64905. DOI:10.1063/1.2162885
Source: PubMed

ABSTRACT The mesoscopic morphologies of linear and graft fluorinated block copolymers of ABCBA and C:BA types, respectively, have been investigated by using dissipative particle dynamics method. Self-assembly in a selective solvent has been examined by the introduction of dimethylformamide as the choice of solvent. By comparing the solubility parameters calculated using atomistic simulations, fluorine-containing segments are found to be immiscible both with other segments of the polymer and with the solvent. Morphologies of the pure linear and graft copolymers were lamellar and cylindrical, respectively. Interfacial tension versus concentration curves have been used to explain the self-assembly behavior of copolymers in solution, as well as to predict the kinetic mechanisms responsible for this behavior.

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Keywords

copolymers
 
dimethylformamide
 
dissipative particle dynamics method
 
fluorine-containing segments
 
graft copolymers
 
graft fluorinated block copolymers
 
Interfacial tension
 
kinetic mechanisms responsible
 
mesoscopic morphologies
 
Morphologies
 
pure linear
 
selective solvent
 
solubility parameters
 
solvent