The synthesis and stimuli-responsiveness of a diphenyl cyclopropenone(DPCP)-centered poly(methyl acrylate)(PMA)are presented.DPCP-centered PMA could release carbon monoxide(CO)upon UV light in a switched on-and-off ma...The synthesis and stimuli-responsiveness of a diphenyl cyclopropenone(DPCP)-centered poly(methyl acrylate)(PMA)are presented.DPCP-centered PMA could release carbon monoxide(CO)upon UV light in a switched on-and-off manner.The CO-releasing process can be reported by the variations in photoluminescence spectra.In addition,DPCP moiety covalently embedded in the crosslinked polyurethane could also release CO under UV light.Of special,DPCP-centered PMA in solution was selectively dissociated at the phenol ester bond under the ultrasound,and a force-induced hydrolyzation reaction was revealed by D20 exchanging^1 H NMR spectra.The kinetic study reveals that small quantity of water could enhance the chain scission rate.This work provides a DPCP-centered polymer for sitespecific CO-releasing and chain dissociation.展开更多
We report the synthesis of ordered mesoporous ceria(mCeO_(2))with highly crystallinity and thermal stability using hybrid polymer templates consisting of organosilanes.Those organosilane-containing polymers can conver...We report the synthesis of ordered mesoporous ceria(mCeO_(2))with highly crystallinity and thermal stability using hybrid polymer templates consisting of organosilanes.Those organosilane-containing polymers can convert into silica-like nanostructures that further serve as thermally stable and mechanically strong templates to prevent the collapse of mesoporous frameworks during thermal-induced crystallization.Using a simple evaporation-induced self-assembly process,control of the interaction between templates and metal precursors allows the co-self-assembly of polymer micelles and Ce^(3+)ions to form uniform porous structures.The porosity is well-retained after calcination up to 900℃.After the thermal engineering at 700℃ for 12 h(mCeO_(2)-700-12 h),mCeO_(2) still has a specific surface area of 96 m^(2) g^(−1) with a pore size of 14 nm.mCeO_(2) is demonstrated to be active for electrochemical oxidation of sulfite.mCeO_(2)-700-12 h with a perfect balance of crystallinity and porosity shows the fastest intrinsic activity that is about 84 times more active than bulk CeO_(2) and 5 times more active than mCeO_(2) that has a lower crystallinity.展开更多
基金financial support by the National Science Foundation of China (No.21604071)
文摘The synthesis and stimuli-responsiveness of a diphenyl cyclopropenone(DPCP)-centered poly(methyl acrylate)(PMA)are presented.DPCP-centered PMA could release carbon monoxide(CO)upon UV light in a switched on-and-off manner.The CO-releasing process can be reported by the variations in photoluminescence spectra.In addition,DPCP moiety covalently embedded in the crosslinked polyurethane could also release CO under UV light.Of special,DPCP-centered PMA in solution was selectively dissociated at the phenol ester bond under the ultrasound,and a force-induced hydrolyzation reaction was revealed by D20 exchanging^1 H NMR spectra.The kinetic study reveals that small quantity of water could enhance the chain scission rate.This work provides a DPCP-centered polymer for sitespecific CO-releasing and chain dissociation.
基金J H is grateful for the financial support from National Science Foundation(CEBT-1705566)The HR-TEM studies were performed using the facilities in the UConn Thermo Fisher Scientific Center for Advanced Microscopy and Materials Analysis(CAMMA).Low-magnification TEM and SEM images were obtained at the Biosciences Electron Microscopy Facility at the University of ConnecticutThis work was also partially supported by the Green Emulsions Micelles and Surfactants(GEMS)Center of the University of Connecticut.
文摘We report the synthesis of ordered mesoporous ceria(mCeO_(2))with highly crystallinity and thermal stability using hybrid polymer templates consisting of organosilanes.Those organosilane-containing polymers can convert into silica-like nanostructures that further serve as thermally stable and mechanically strong templates to prevent the collapse of mesoporous frameworks during thermal-induced crystallization.Using a simple evaporation-induced self-assembly process,control of the interaction between templates and metal precursors allows the co-self-assembly of polymer micelles and Ce^(3+)ions to form uniform porous structures.The porosity is well-retained after calcination up to 900℃.After the thermal engineering at 700℃ for 12 h(mCeO_(2)-700-12 h),mCeO_(2) still has a specific surface area of 96 m^(2) g^(−1) with a pore size of 14 nm.mCeO_(2) is demonstrated to be active for electrochemical oxidation of sulfite.mCeO_(2)-700-12 h with a perfect balance of crystallinity and porosity shows the fastest intrinsic activity that is about 84 times more active than bulk CeO_(2) and 5 times more active than mCeO_(2) that has a lower crystallinity.
