Water surface covering of fluorinated amphiphilic triblock copolymers: surface pressure-area and X-ray reflectivity investigations.
Monolayers of ABA amphiphilic triblock block copolymers are studied using surface pressure-area and X-ray reflectivity (XR) measurements. The triblock copolymers are composed of long poly(ethylene oxide) (PEO) middle blocks with poly((perfluorohexyl)ethyl methacrylate) (PFMA) end blocks. The surface pressure-area isotherms of water-insoluble species show two pseudoplateaus. The plateau at low surface pressure is consistent with the pseudoplateau observed for PEO copolymers in the literature. The plateau in the brush region can be assigned to the horizontal to vertical rearrangement of whole PFMA chains at the air-water interface, which was followed by XR measurements. For water-soluble species with a very low amount of PFMA no (significant) second pseudoplateau and no enrichment of PFMA at the air-water interface were observed.
Busse
Karsten
K
Institute of Physical Chemistry, Department of Chemistry, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany. karsten.busse@chemie.uni-halle.de
Peetla
Chiranjeevi
C
Kressler
Jörg
J