Dimethylaminochalcone-terminated PNIPAM (PNIPAM-DMAC) with intelligent fluorescence was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization of N-isopropylacrylamide (NIPAM) with dimethylaminochalcone-containing trithiocarbonate chain transfer agent (CTA) in THF solution using AIBN as initiator

and the structure was confirmed by FTIR

1H-NMR and UV-Vis spectroscopy.The thermosensitivity of PNIPAM-DMAC and the fluorescence responsive to solvent polarity

temperature and molecular recognition were investigated.The results show that PNIPAM-DMAC has a lower critical solution temperature (LCST) poly(N-isopropylacrylamide) (PNIPAM)

and the LCST of PNIPAM-DMAC decreases with the increase of polymer molecular weight and aqueous solution concentration

increases with the addition of -cyclodextrin (-CD).With the increase of the solvent polarity

the fluorescence emitting wavelength of PNIPAM-DMAC redshifts basically and the intensity of fluorescence possesses maximum and minimum values

which exhibits solvent polarity sensitive fluorescence properties.Compared with the fluorescence of PNIPAM-DMAC aqueous solutions in the low and high temperatures

it is found that the fluorescence intensity of PNIPAM-DMAC has been obviously enhanced and the wavelength blueshifts in the high temperatures and the fluorescence spectroscopy changes reversibly with respect to the temperature fluctuation

which endows PNIPAM-DMAC with the reversible temperature on/off fluorescence properties.After the addition of -CD to PNIPAM-DMAC aqueous solutions

the fluorescence intensity is enhanced and the wavelength shifts blue slightly

which shows molecular recognition sensitive fluorescence properties.