In this article, novel silver nanoparticles immobilized on macroporous polybenzoxazine nanocomposites （Ag-poly（BA-ddm）^x main） were prepared as catalysts for catalytic reduction reaction. For this purpose, a main-...In this article, novel silver nanoparticles immobilized on macroporous polybenzoxazine nanocomposites （Ag-poly（BA-ddm）^x main） were prepared as catalysts for catalytic reduction reaction. For this purpose, a main-chain type benzoxazine was cured in dimethyl sulfoxide by thermally activated ring-opening polymerization at 180℃ for 2days followed by the reduction of silver nitrate in homogeneous polybenzoxazine solution. The porous structure of the resin was confirmed by scanning electron microscope （SEM） analysis and N2 adsorption]desorption studies. Besides, transmission electron microscopy images showed that spherical particles （around 3-10 nm in sized） are dispersed in Ag-poly （BA-ddm）^x main network. The catalytic activity of the as-prepared nanocomposite has been investigated by photometrically monitoring the reduction of methylene blue by an excess of NaBH4. The kinetic data of the reduction reaction was explained by the assumption of a pseudo-first-order reaction with regard to methylene blue （MB）. As evidence by Ultraviolet （UV） spectral analysis, the Ag-poly（BA-ddm）^x main catalyst possesses excellent catalytic reduction of MB, and no deactivation or poisoning of the catalyst was observed. The results demonstrate that porous polybenzoxazine supported silver nanoparticles can be applied as reusable catalysts with satisfied catalytic activity.展开更多
A novel polyhedral oligomeric silsesquioxane(POSS)-based organic-inorganic hybrid nanocomposite(EF-POSS) was prepared by Pt-catalyzed hydrosilylation reaction of octahydridosilsesquioxane(T_8H_8,POSS) with a luminesce...A novel polyhedral oligomeric silsesquioxane(POSS)-based organic-inorganic hybrid nanocomposite(EF-POSS) was prepared by Pt-catalyzed hydrosilylation reaction of octahydridosilsesquioxane(T_8H_8,POSS) with a luminescent substituted acetylene(2- ethynyl-7-(4-(4-methylstyryl)styryl)-9,9-dioctyl-9H-fluorene(EF)) in high yield.The hybrid nanocomposite was soluble in common solvents such as CH_2Cl_2,CHCl_3,THF and 1,4-dioxane.Its structure and property were characterized by FTIR, NMR,TGA,UV and PL,respectively.The results show that the hybrid nanocomposite with high thermal stability emits stable blue light as a result of photo excitation and possesses high photoluminescence quantum efficiency(φ_(FL)).展开更多
Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization a...Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,^(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS cores.Spectroscopic ellipsometry and dielectric consta...展开更多
Nanocomposites（PMSEPE/Q8M8^H） were prepared via solution blending of octakis（dimethylsiloxy）octasilsesquoixane（Q8M8^H） into poly（dimethylsilyleneethynylenephenyleneethynyle ne）（PMSEPE）. PMSEPE/Q8M8^H nanocom...Nanocomposites（PMSEPE/Q8M8^H） were prepared via solution blending of octakis（dimethylsiloxy）octasilsesquoixane（Q8M8^H） into poly（dimethylsilyleneethynylenephenyleneethynyle ne）（PMSEPE）. PMSEPE/Q8M8^H nanocomposites were characterized by Fourier transform infrared（FT-IR） spectroscopy, rheological measurement, differential scanning calorimetry（DSC）, scanning electron microscopy（SEM） and thermal gravimetric analysis（TGA）. The experimental results show that the hydrosilylation reaction in PMSEPE/Q8M8^H nanocomposites occurs slowly exceeding 180 ℃. PMSEPE/Q8M8^H nanocomposites can be cured at temperatures less than 260 ℃ and the cube structure of Q8M8^H keeps stable during the curing process. POSS domains are evenly dispersed in the cured nanocomposite. However, serious aggregation of POSS occurs at 15% Q8M8^H content. The thermal and thermooxidative stabilities of PMSEPE/Q8M8^H nanocomposites obviously depend on the content of Q8M8^H. The incorporation of Q8M8^H can effectively enhance the thermal and thermooxidative stabilities of cured PMSEPE. PMSEPE/Q8M8^H nanocomposites can be the candidates for applications in high temperature environment.展开更多
基金the National Natural Science Foundation of China(NSFC)for their financial support(Nos.51603093 and 21403091)supported by the Science and Technology Agency of Jiangsu Province(No.BK 20160515)China Postdoctoral Science Foundation(No.2016M600369)
文摘In this article, novel silver nanoparticles immobilized on macroporous polybenzoxazine nanocomposites （Ag-poly（BA-ddm）^x main） were prepared as catalysts for catalytic reduction reaction. For this purpose, a main-chain type benzoxazine was cured in dimethyl sulfoxide by thermally activated ring-opening polymerization at 180℃ for 2days followed by the reduction of silver nitrate in homogeneous polybenzoxazine solution. The porous structure of the resin was confirmed by scanning electron microscope （SEM） analysis and N2 adsorption]desorption studies. Besides, transmission electron microscopy images showed that spherical particles （around 3-10 nm in sized） are dispersed in Ag-poly （BA-ddm）^x main network. The catalytic activity of the as-prepared nanocomposite has been investigated by photometrically monitoring the reduction of methylene blue by an excess of NaBH4. The kinetic data of the reduction reaction was explained by the assumption of a pseudo-first-order reaction with regard to methylene blue （MB）. As evidence by Ultraviolet （UV） spectral analysis, the Ag-poly（BA-ddm）^x main catalyst possesses excellent catalytic reduction of MB, and no deactivation or poisoning of the catalyst was observed. The results demonstrate that porous polybenzoxazine supported silver nanoparticles can be applied as reusable catalysts with satisfied catalytic activity.
基金supported by the National Natural Science Fund of China(Nos.90606011 and 50472038)Ph.D.Program Foundation of Ministry of Education of China(No.20070255012)+3 种基金Shanghai Leading Academic Discipline Project(No.B603)the Program of Introducing Talents of Discipline to Universities(No.111-2- 04)Open Project of the State Key Laboratory of Crystal Materials(No.KF0809)Youth Scientific Research Fund of Anhui University and the Excellent Youth Fund in University of Anhui Province(No.2008jq1020)
文摘A novel polyhedral oligomeric silsesquioxane(POSS)-based organic-inorganic hybrid nanocomposite(EF-POSS) was prepared by Pt-catalyzed hydrosilylation reaction of octahydridosilsesquioxane(T_8H_8,POSS) with a luminescent substituted acetylene(2- ethynyl-7-(4-(4-methylstyryl)styryl)-9,9-dioctyl-9H-fluorene(EF)) in high yield.The hybrid nanocomposite was soluble in common solvents such as CH_2Cl_2,CHCl_3,THF and 1,4-dioxane.Its structure and property were characterized by FTIR, NMR,TGA,UV and PL,respectively.The results show that the hybrid nanocomposite with high thermal stability emits stable blue light as a result of photo excitation and possesses high photoluminescence quantum efficiency(φ_(FL)).
基金financially supported by the National Natural Science Foundation of China(Nos.90606011, 50472038 and 2097401)PhD Program Foundation of Ministry of Education of China(No.20070255012)+3 种基金Shanghai Leading Academic Discipline Project(No.B603)Open Project of The State Key Laboratory of Crystal Materials(KF0809)the Program of Introducing Talents of Discipline to Universities(No.111-2-04)Doctoral Dissertation Innovation Project(No.BC200907)
文摘Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,^(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS cores.Spectroscopic ellipsometry and dielectric consta...
基金Funded by the Shanghai Leading Academic Discipline Project(B502)the Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application(Soochow University)
文摘Nanocomposites（PMSEPE/Q8M8^H） were prepared via solution blending of octakis（dimethylsiloxy）octasilsesquoixane（Q8M8^H） into poly（dimethylsilyleneethynylenephenyleneethynyle ne）（PMSEPE）. PMSEPE/Q8M8^H nanocomposites were characterized by Fourier transform infrared（FT-IR） spectroscopy, rheological measurement, differential scanning calorimetry（DSC）, scanning electron microscopy（SEM） and thermal gravimetric analysis（TGA）. The experimental results show that the hydrosilylation reaction in PMSEPE/Q8M8^H nanocomposites occurs slowly exceeding 180 ℃. PMSEPE/Q8M8^H nanocomposites can be cured at temperatures less than 260 ℃ and the cube structure of Q8M8^H keeps stable during the curing process. POSS domains are evenly dispersed in the cured nanocomposite. However, serious aggregation of POSS occurs at 15% Q8M8^H content. The thermal and thermooxidative stabilities of PMSEPE/Q8M8^H nanocomposites obviously depend on the content of Q8M8^H. The incorporation of Q8M8^H can effectively enhance the thermal and thermooxidative stabilities of cured PMSEPE. PMSEPE/Q8M8^H nanocomposites can be the candidates for applications in high temperature environment.
