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.
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.