The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution int...The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution into the modified PAMAM dendrimers that were dissolved in certain solvent. The quantity of Ti contained in the complexes increased as the adding amount of TiCl 4 was increased. The polymerization of α methyl styrene catalyzed by the complexes was accomplished and it has shown that the complexes possessed catalytic function.展开更多
An azyl group of ethylene diamine was protected by N-tert-butoxycarbonyl.The remaining azyl group then successively reacted with methyl acrylate, ethylene diamine and methyl acrylate again to afford the compound Boc-N...An azyl group of ethylene diamine was protected by N-tert-butoxycarbonyl.The remaining azyl group then successively reacted with methyl acrylate, ethylene diamine and methyl acrylate again to afford the compound Boc-NH 2-(B-COOCH 3) 4 3 (AB-4).The ester groups and the Boc-end group of 3 were transferred to carboxylate 4 and azyl group 5 via hydrolyzation and deprotection respectively.The fan-shape dendron molecules with 16 exterior groups 6 were obtained by condensation of 4 and 5 in the presence of DCC.The dumbbell-like dendrimer molecules 7 could expediently prepared by coupling the dendrons with two functional groups of hexanedioyl chloride.The paper describes the synthesis procedures,reports the characterization results of FTIR、 1H-NMR、 13C-NMR and MALDI-TOF.Comparing with the PAMAM dendrimers from the divergent method, the synthesized compounds possess accurate structures and few defections.展开更多
H 2PtCl 6 was coordinated with the carboxyl-terminated G4.5PAMAM dendrimer molecules (PAMAMC) in aqueous solution,followed by reduction using NaBH 4 as reducer,and formed Pt-PAMAMC hybrid nano-particles.The stable mul...H 2PtCl 6 was coordinated with the carboxyl-terminated G4.5PAMAM dendrimer molecules (PAMAMC) in aqueous solution,followed by reduction using NaBH 4 as reducer,and formed Pt-PAMAMC hybrid nano-particles.The stable multilayer films were obtained by fabricating diazo resin(DR) with these hybrid nanoparticles (Pt-PAMAMC) and PAMAMC,respectively.The films were subsequently irradiated under UV-light.It was found that the films from Pt-PAMAMC as polyanions exhibit stable frictional responses under the applied load,and the lubricative property of the films from Pt-PAMAMC hybrid nanoparticles is obviously superior to that of the films from dendrimer without platinum inside.展开更多
An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential d...An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential deposition. It shows that the step by step depositions carried out smoothly by monitoring with UV Vis spectrometer. The multilayer film is rather flat with a mean roughness of \{0.39 nm\} determined by AFM. The average thickness of a bilayer is \{5.0 nm\} obtained from XRD, which indicates that the dendrimers molecules were compressed and possess high flattening.展开更多
The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome ...The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome C in some extent.For example,the reduction rate of Fe Ⅲ cytochrome C to Fe Ⅱ cytochrome C by ascorbic acid was clearly slowed down because of the interaction between cytochrome C and PAMAM dendrimers.The reaction happened only betweem Fe Ⅲ cytochrome C and ascorbic acid,it showed a pseudo first order constant of 3 48 min -1 .When PAMAMC (G2 5 or 3 5) dendrimers were added in the reaction system,the pseudo first order constant dropped to 1 40 or 1 32 ?min -1 .The association constant of 1:1 cytochrome C G2 5C is 2 4×10 4 and the association constant of 1:1 cytochrome C G3.5C is 2 6×10 4.展开更多
文摘The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution into the modified PAMAM dendrimers that were dissolved in certain solvent. The quantity of Ti contained in the complexes increased as the adding amount of TiCl 4 was increased. The polymerization of α methyl styrene catalyzed by the complexes was accomplished and it has shown that the complexes possessed catalytic function.
文摘An azyl group of ethylene diamine was protected by N-tert-butoxycarbonyl.The remaining azyl group then successively reacted with methyl acrylate, ethylene diamine and methyl acrylate again to afford the compound Boc-NH 2-(B-COOCH 3) 4 3 (AB-4).The ester groups and the Boc-end group of 3 were transferred to carboxylate 4 and azyl group 5 via hydrolyzation and deprotection respectively.The fan-shape dendron molecules with 16 exterior groups 6 were obtained by condensation of 4 and 5 in the presence of DCC.The dumbbell-like dendrimer molecules 7 could expediently prepared by coupling the dendrons with two functional groups of hexanedioyl chloride.The paper describes the synthesis procedures,reports the characterization results of FTIR、 1H-NMR、 13C-NMR and MALDI-TOF.Comparing with the PAMAM dendrimers from the divergent method, the synthesized compounds possess accurate structures and few defections.
文摘H 2PtCl 6 was coordinated with the carboxyl-terminated G4.5PAMAM dendrimer molecules (PAMAMC) in aqueous solution,followed by reduction using NaBH 4 as reducer,and formed Pt-PAMAMC hybrid nano-particles.The stable multilayer films were obtained by fabricating diazo resin(DR) with these hybrid nanoparticles (Pt-PAMAMC) and PAMAMC,respectively.The films were subsequently irradiated under UV-light.It was found that the films from Pt-PAMAMC as polyanions exhibit stable frictional responses under the applied load,and the lubricative property of the films from Pt-PAMAMC hybrid nanoparticles is obviously superior to that of the films from dendrimer without platinum inside.
文摘An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium \%p\% styrenesulfonate) (PSS) as polyainon was fabricated \%via\% sequential deposition. It shows that the step by step depositions carried out smoothly by monitoring with UV Vis spectrometer. The multilayer film is rather flat with a mean roughness of \{0.39 nm\} determined by AFM. The average thickness of a bilayer is \{5.0 nm\} obtained from XRD, which indicates that the dendrimers molecules were compressed and possess high flattening.
文摘The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome C in some extent.For example,the reduction rate of Fe Ⅲ cytochrome C to Fe Ⅱ cytochrome C by ascorbic acid was clearly slowed down because of the interaction between cytochrome C and PAMAM dendrimers.The reaction happened only betweem Fe Ⅲ cytochrome C and ascorbic acid,it showed a pseudo first order constant of 3 48 min -1 .When PAMAMC (G2 5 or 3 5) dendrimers were added in the reaction system,the pseudo first order constant dropped to 1 40 or 1 32 ?min -1 .The association constant of 1:1 cytochrome C G2 5C is 2 4×10 4 and the association constant of 1:1 cytochrome C G3.5C is 2 6×10 4.