Conformational Behavior of a Series of N-Isopropylacrylamide−Bromostyrene Statistical Copolymers via Phosphorescence Measurements

摘要: This paper reports on the first observation of phosphorescence emission in a thermoresponsive polymer aqueous media. Random copolymerization N-isopropylacrylamide, NIPAM, with bromostyrene, BrSTY, promotes efficient intersystem crossing into triplet manifold, via heavy atom effect, an acenaphthylene label allowing generation millisecond time scale. Luminescence techniques such as fluorescence time-resolved anisotropy, excited-state lifetime, and pyrene solubilization experiments have proven useful probing effects modification upon behavior PNIPAM: BrSTY alters hydrophobic/hydrophilic balance serves to decrease lower critical solution temperature, LCST, resultant polymer. The LCST is marked by change conformation macromolecule form expanded water-swollen structure compact globule. globular BrSTY-modified samples so protective that susta...