A study of the interaction between dialkyldimethylammonium bromides and tri-n-octylphosphine oxide (topo) in mixed monolayers at the air/water interface

作者：Hac Wydro K^*; Wydro P; Dynarowicz Latka P

来源：Journal of Colloid and Interface Science, 2004, 278(1): 206-214.

DOI：10.1016/j.jcis.2004.05.014

• dialkyldimethylammonium salts
• TOPO
• mixed monolayers
• compression modulus
• excess free energy of mixing

The interactions between tri-n-octylphosphine oxide (TOPO) and a series of dialkyldimethylammonium bromides (DXDAB) in mixed Langmuir monolayers have been investigated. The mean area per molecule in mixed monolayers (A(12)) and the excess area (A(Exc)), exhibited deviations from ideal behavior for all the investigated systems. The molecular interactions have been quantified by the values of the excess free energy of mixing (AG(Exc)). The monolayers stability has been examined with the total free energy of mixing (DeltaG(M)) values. The obtained results indicate that the length of the hydrocarbon chain in dialkyldimethylammonium salts affects the molecular packing and determines the strength of interactions with TOPO molecules.

• 出版日期2004-10-1