| Nanosilver/poly(2-acrylamido-2-methylpropanesulfonate sodium)(PAMPS) composites,nanosilver/Poly(acetoacetoxyethy1methacrylate(AAEM))composites,nanosil ver/poly(acetoacetoxyethy1methacrylate(AAEM)-styrene(St))[P(AAEM-St)] composites and nanocopper/P(AAEM-St) composites were prepared by radiation method without gas protection in this paper,, in which metallic ion was reduced to metal nanoparticles and the monomer was polymerized simultaneously.Nanosilver/PAMPS composites have been synthesized by microwave. The mechanism of catalytic reduction of sliver ion by atomic nitrogen (from PAMPS) has been explored. The composites were characterized by ultraviolet and visible spectroscopy (UV-vis), X-ray diffractometer, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR), thermal-gravimetry analyzer (TGA), respectively. The results showed that silver nanoparticles were possessed face-centered cubic structure and homogeneously dispersed in PAMPS matrix. XPS analysis revealed the interaction between nano-Ag and PAMPS matrix. TGA proved that the thermal stability of the pure PAMPS was higher than that of the nano-Ag/PAMPS composites.Nanosilver/PAAEM composites, nanosilver/P(AAEM-St) composites and nanocopper/P(AAEM-St) composites were synthesized via emulsifier-free emulsion by ultrasonic. The morphology, structure, thermal stability and the interaction between nanosilver and matrix of the nanosilver/PAAEM composites and nanocopper/P(AAEM-St) composites were characterized by the above characterization method. The results showed that there existed an interaction between metal nanoparticles and C=O associated with acetoacetoxy from AAEM polymer. And thermal stability of the matrices of nanocomposites was changing due to metal nanoparticles dispersed in the composites. Nanosilver/P(AAEM-St) composites were characterized by UV-vis, XRD and TEM, respectively. The thermal stability and thermal degradation kinetics of the P(AAEM-St) were investigated by using TGA, as Kissinger, Flynn-Wall-Ozawa and Starink methods, respectively. The results showed that the lowest decomposition temperature of nano-Ag/P(AAEM-St) composites was530.44K in the conversion rate of5%, which were decreased down34.13K than that of the P(AAEM-St)(574.57K), the average value of thermal degradation apparent activation energy of nano-Ag/P(AAEM-St) calculated by various methods was lower than that of the pure (AAEM-St) copolymer. Those proved that the thermal stability of the pure P(AAEM-St) was better than that of the nano-Ag/P(AAEM-St) composites, because of thermocatalytic discomposion of nano-Ag in the matrix. TEM results showed that the above metal nanoparticles were dispersed homogeneously in matrix and possessed face-centered cubic structure and nearly spherical shape or spherical morphology. |
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