Temperature Responsiveness of the PDMAEMA Stars

Linear PDMAEMA exhibits a lower critical solution temperature (LCST) in water, that is the polymer becomes insoluble at elevated temperatures. We have 

We found that the observed cloud points (determined by turbidity measurements at 500 nm) only depend on the molecular weights (according to a Flory-Huggins behavior) at high pH, and that the architecture of the polymer does not show a significant impact. However, at lower pH a slight modulation is observed in addition to the shift of the whole cloud point curve to elevated temperatures, the cloud points 

Interestingly, in the buffered solutions of PDMAEMA stars with 0.1 M NaCl, addition of small amounts of multivalent counterions can induce an upper critical solution temperature (UCST), i.e., demixing upon lowering the temperature (see 

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