Laser light scattering and isothermal titration calorimetric studies of poly(ethylene oxide) aqueous solution in presence of sodium dodecyl sulfate.
The aqueous solution of poly(ethylene oxide) (PEO) in the presence of different concentrations of sodium dodecyl sulfate (SDS) was examined by laser light scattering and isothermal titration calorimetric techniques. A small fraction of PEO aggregates were found to coexist with unimeric PEO chains in dilute solution. The presence of monovalent salt does not alter the hydrodynamic properties of PEO in aqueous solution. Addition of a monovalent anionic surfactant, such as SDS, induces cooperative binding of surfactant monomers to PEO backbones at SDS concentrations ranging from 4.0 mM (critical aggregation concentration) to 16.5 mM (saturation concentration). The hydrodynamic radius of PEO unimers decreases initially and then increases with SDS concentration, resulting from the structural reorganization of the PEO/SDS complex. Beyond the saturation concentration, the hydrodynamic radii of PEO/SDS complex are independent of SDS concentration.
Dai
Sheng
S
Singapore-MIT Alliance, Nanyang Technological University, Singapore 639798, Republic of Singapore.
Tam
Kam Chiu
KC
D007834:Lasers; D011092:Polyethylene Glycols / Q000737:chemistry*; D012542:Scattering, Radiation; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry; D013816:Thermodynamics; D017186:Titrimetry; D014867:Water / Q000737:chemistry
D012996:Solutions; D014867:Water; D012967:Sodium Dodecyl Sulfate; D011092:Polyethylene Glycols