Abstract

Water-soluble poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PPO) triblock copolymers are high-molecular-weight nonionic copolymers and form micellar solutions and liquid-crystalline mesophases in water. We studied the temperature dependence of polymer and water self-diffusion in solutions and lyotropic mesophases of the PEO13 PPO30 PEO13/water and PEO21 PPO47 PEO21/water binary systems. The self-diffusion measurements were performed by means of the pulsed field gradient spin-echo NMR method. The analysis of the water mobility was realised using “the obstruction factor” and “the two-site model”, which consider the reduction of the water self-diffusion due to the microstructure of the lyotropic aggregates and to the presence of one part of the solvent bound to the polymer aggregate surfaces. We calculated the water obstruction factors and the hydration numbers as a function both of the polymer composition and of the temperature. The results are compared with the data obtained in mesophases formed by classical surfactants.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.