Synthesis And Characterization Of Nano-Ag /Nitrogen-containing Polymers Composites By Microwave Irradiating Method

Nano-Ag/PVP composite, nano-Ag/PAM composite and nano-Ag/PAMPS composite materials were prepared respectively by microwave irradiating. The composite materials were characterized by means of XPS, TEM, and so on. Meanwhile, the mechanism of catalytic reduction and the interaction between nano Ag and different polymers were discussed.Nano-silver/polyvinylpyrrolidone (PVP) composite materials were synthesized in the silver nitrate solution containing PVP by microwave. The sample was characterized by kinds of experimental techniques. UV-Vis showed that the strong narrow absorption peak appeared at 415nm for nano-silver. With the microwave time or reaction time increased, the absorption peak of silver in the nano composites was shifted to long wavelength, meanwhile, behaved multi-peaks. TEM suggested that nano silver particles were spherical with 10-25nm and homogeneously dispersed in the PVP matrix, however other shape, such as triangle were emerged with the change of concentration and reaction time. XRD results indicated the presence of nano silver with face-centered cubic structure, the nano silver particles were reduced to stabilize by PVP as matrix not only based on this side, but also based on the interaction between PVP and nano silver suggested by XPS results.Nano-silver/poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) and Nano-silver/Polyacrylamide(PAM) composite materials respectively were synthesized bi-in situ from silver nitrate solution with acrylamide (AM) or 2-acrylamido-2-methylpropanesulfonic acid(AMPS) monomer under microwave irradiation, with potassium persulfate as initiator. FTIR showed that poly(2-acrylamido-2-methylpropanesulfonic acid) and polyacrylamide were successfully synthesized;Comparing the TEM images of nano-silver in different polymer matrix, it indicated that nano Ag emerged different patterns and shapes in different polymer, such triangle and diamond in PAM, while spherical in PAMPS. It was interesting to find there was absorption peak of silver in Uv-vis spectra of nano Ag/PAMPS composites at 417nm,while there no peak for nano Ag/PAM composites. XPS suggested that the energy peak of nitrogen in PAMPS shifted to 0.24eV lower than in PAM, meanwhile the energy peak of Ag shifted in PAMPS shifted 0.15eV higher than in PAMIt can be concluded that there was interaction between nano silver and polymer. Due to their different microstructure in different polymer, the interaction intensity was different.