Thermoresponsive reversible behavior of multistimuli pluronic-based pentablock copolymer at the air-water interface
|Title||Thermoresponsive reversible behavior of multistimuli pluronic-based pentablock copolymer at the air-water interface|
|Publication Type||Journal Article|
|Year of Publication||2007|
|Authors||Peleshanko S, Anderson KD, Goodman M, Determan MD, Mallapragada SK, Tsukruk VV|
|Type of Article||Article|
|Keywords||AMPHIPHILIC, ASSOCIATION BEHAVIOR, BLOCK-COPOLYMERS, DIBLOCK COPOLYMERS, GROUPS, LANGMUIR, MONODENDRONS, monolayers, REORGANIZATION, surface, TERMINAL, TRANSFER RADICAL POLYMERIZATION|
Surface behavior of the pH- and thermoresponsive amphiphilic ABCBA pentablock copolymer has been studied with respect to the environmental conditions. We demonstrate that the pentablock copolymer poly((diethylaminoethyl methacrylate)-b-(ethylene oxide)-b-(propylene oxide)-b-(ethylene oxide)-b-(diethylaminoethyl methacrylate)) possesses reversible temperature changes at the air-water interface in a narrow pH range of the water subphase. Significant diversity in the surface morphology of pentablock copolymer monolayers at different pH and temperatures observed were related to the corresponding reorganization of central and terminal blocks. Remarkable reversible variations of the surface pressure observed for the Langmuir monolayers at pH 7.4 in the course of heating and cooling between 27 and 50 degrees C is associated with conformational transformations of terminal blocks crossing the phase line in the vicinity of the lower critical solution temperature point. The observed thermoresponsive surface behavior can be exploited for modeling of the corresponding behavior of pentablock copolymers adsorbed onto various biointerfaces for intracellular delivery for deeper understanding of stimuli-responsive transformations relevant to controlled drug and biomolecules release and retention.