Tailored non-ionic polymers with UCST-type phase transition properties in water and electrolytes

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The project deals with the synthesis of tailor made non-ionic polymers showing upper critical solution temperature (UCST)-type phase transitions in water and electrolytes and the investigation of the phase transition behavior on different length and time scales using scattering methods. The term water-soluble thermoresponsive polymer is at present a synonym for polymers showing lower critical solution temperature (LCST). The non-ionic polymers which exhibit upper critical solution temperature (UCST) in water and aqueous electrolyte solutions are rare with very limited examples. This yet open, innovative, promising and not very well studied area is the topic of the present proposal. We propose to make appropriate non-ionic polymers capable of undergoing thermally reversible hydrogen bonding leading to UCST-type phase transitions based on homo- and co-polymers of (meth)acrylamide and alpha-substituted derivatives ((alkyl)acrylamides). These tailor made polymers would provide a series of samples with systematic variation in glass transition temperature (chain mobility) and hydrophilic/hydrophobic ratio for studying the phase-transition behavior as a function of polymer and electrolyte concentration, heating/cooling rates, chain mobility, molar mass and polymer microstructure by light scattering (global length scales) as well as SANS (local morphologies).