Poly （methyl methacrylate） （PMMA） brushes were synthesized from silicon wafers via surface initiated atom transfer radical polymerization （SI-ATRP）. Energy disperse spectroscopy （EDS） and atomic force microsco...Poly （methyl methacrylate） （PMMA） brushes were synthesized from silicon wafers via surface initiated atom transfer radical polymerization （SI-ATRP）. Energy disperse spectroscopy （EDS） and atomic force microscopy （AFM） confirmed that PMMA brushes were successfully prepared on the silicon wafers, and the surface became more hydrophobic according to the contact angle of 69~. It is found that CuCI/1, 1, 4, 7, 10, 10-hexamethyl triethylenetetramine （HMTETA） system is more suitable than CuBr/N, N, N′, N″, N′″-pentamethyl diethylenetriamine （PMDETA） system to control the free radical polymerization of MMA in solution. Nevertheless, better control on the thickness of PMMA brushes was achieved in CuBr/PMDETA than in CuC1/HMTETA due to higher activity and better reversibility of the former system.展开更多
Atom transfer radical polymerizations （ATRPs） of styrene （St） in bulk initiated by six iniferter reagents were carried out, respectively, in the present of copper （1） bromide （CuBr） and N, N,N＇,N＂,N＂-pentam...Atom transfer radical polymerizations （ATRPs） of styrene （St） in bulk initiated by six iniferter reagents were carried out, respectively, in the present of copper （1） bromide （CuBr） and N, N,N＇,N＂,N＂-pentamethyldiethylenetriamine （PMDETA） at 115℃. All the kinetic plots were first-order with respect to the monomer concentrations. At the same time, the corresponding molecular weights of the polymers increased linearly with the respective monomer conversions. Furthermore, the molecular weight distributions remained relatively narrow （Mw/Mn〈1.50） in all cases. Solution ATRP of St in dimethyl- formamide （DMF） initiated by benzyl N, N-diethyldithiocarba- mate （BDC） also showed the characteristics of living radical polymerization. The results of 1H NMR analysis and chain extension experiment confirmed that the well-defined polystyrene （PS） bearing photo-liable group has been obtained via ATRP of St using photoiniferter reagents as the initiators.展开更多
An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunab...An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunable particles in DMF/water mixtures. The polymer nanoparticles can be used for cell imaging, which provides a potential stable fluorescent tool to monitor the distribution of drugs and bioconjugates in living cells.展开更多
基金Project(21376271)supported by the National Natural Science Foundation of ChinaProject(2013)supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,China+2 种基金Projects(CL12129,201310533008)supported by the Undergraduates Innovative Training Foundation of Central South University,ChinaProject(Z12060)supported by the Undergraduate Free Exploration Innovation Foundation of Central South University,ChinaProject(CSUZC2013008)supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘Poly （methyl methacrylate） （PMMA） brushes were synthesized from silicon wafers via surface initiated atom transfer radical polymerization （SI-ATRP）. Energy disperse spectroscopy （EDS） and atomic force microscopy （AFM） confirmed that PMMA brushes were successfully prepared on the silicon wafers, and the surface became more hydrophobic according to the contact angle of 69~. It is found that CuCI/1, 1, 4, 7, 10, 10-hexamethyl triethylenetetramine （HMTETA） system is more suitable than CuBr/N, N, N′, N″, N′″-pentamethyl diethylenetriamine （PMDETA） system to control the free radical polymerization of MMA in solution. Nevertheless, better control on the thickness of PMMA brushes was achieved in CuBr/PMDETA than in CuC1/HMTETA due to higher activity and better reversibility of the former system.
基金Acknowledgments： The work was supported by the National Nature Science Foundation of China （No. 20574050）, the Science and Technology Development Planning of Jiangsu Province （No. BK2007702 and BK2007048）, and the Nature Science Key Basic Research of Jiangsu Province for Higher Education （No. 05KJA15008）.
文摘Atom transfer radical polymerizations （ATRPs） of styrene （St） in bulk initiated by six iniferter reagents were carried out, respectively, in the present of copper （1） bromide （CuBr） and N, N,N＇,N＂,N＂-pentamethyldiethylenetriamine （PMDETA） at 115℃. All the kinetic plots were first-order with respect to the monomer concentrations. At the same time, the corresponding molecular weights of the polymers increased linearly with the respective monomer conversions. Furthermore, the molecular weight distributions remained relatively narrow （Mw/Mn〈1.50） in all cases. Solution ATRP of St in dimethyl- formamide （DMF） initiated by benzyl N, N-diethyldithiocarba- mate （BDC） also showed the characteristics of living radical polymerization. The results of 1H NMR analysis and chain extension experiment confirmed that the well-defined polystyrene （PS） bearing photo-liable group has been obtained via ATRP of St using photoiniferter reagents as the initiators.
基金supported by the National Natural Science Foundation of China (20974028, 20974098, and 21174120)the National Basic Research Program of China (2009CB623605)+1 种基金the Research Grants Council of Hong Kong (603509, HKUST2/CRF/10, 604711, and N_HKUST620/11)B.Z.T. thanks the support from the Cao Guangbiao Foundation of Zhejiang University
文摘An amphiphilic polymer bearing tetraphenylethene (TPE) moiety was synthesized by convenient reactions. The polymer exhibits unique aggregation-induced emission (AIE) characteristics and can self-assemble to size-tunable particles in DMF/water mixtures. The polymer nanoparticles can be used for cell imaging, which provides a potential stable fluorescent tool to monitor the distribution of drugs and bioconjugates in living cells.
