Synthesis and Characterization of Polymeric Composites Embeded with Silver Nanoparticles

Abstract

Silver nanoparticles were synthesized by chemical reduction method. The Ag nanoparticles (AgNP) were characterized using UV-Vis spectroscopy which shows an absorption band at 420 nm confirming the formation of nanoparticles. For any practical application of the silver nanoparticles it is necessary to stabilize it which can be done by making a composite. In the present studies three polymers were chosen such that AgNP could be put to some practical use. Polyvinyl Alcohol (PVA), Polypyrrole (Ppy) and Carboxymethyl cellulose (CMC) are important for use in textiles, electronics and food/drug technologies respectively. Polymeric composites of PVA, PPy, and CMC were prepared by mixing the aqueous solutions of the respective polymers and the colloidal suspension of preformed silver nanoparticles. Various compositions containing 1% to 5% of Ag nanoparticles were prepared. Thin films of these composites were characterized by UV-Vis spectroscopy, X-ray diffraction and Scanning electron microscopy. X-ray diffraction showed the presence of the peaks at 2θ values of 38.1°, 44.2°, 64.4 and 78.2° corresponding to cubic phase of silver metal. SEM photographs revealed the presence of Ag nanoparticles of sizes varying from 40 to 80 nm. The electrical conductivity of these materials was studied using the four probe method. The conductivity was found to increase from 10<sup>–6</sup> for control samples to 10<sup>–3</sup> S/cm after the formation of the nanocomposites

Synthesis of High Temperature Stable Carbon Coated Metal Nanoparticles in AlPO4 Based Matrix In Situ in Oxidative Atmosphere

“…Absorption peak obtained in this region is broad indicating the presence of nanoparticles of different sizes. The silver nanoparticles usually show absorption peak around this region as reported in the literature …”

Green synthesis and antibacterial effects of aqueous colloidal solutions of silver nanoparticles using camomile terpenoids as a combined reducing and capping agent

“…On the spectrum of CE two peaks are present at 280 and 320 nm corresponding to terpenoid [37–40]. These peaks disappear in the spectra measured for AgNPs/CE and AgNPs/G.…”

“…The involvement of phenolics, proteins, terpenoids and other reducing agents in the synthesis of metal nanoparticles has been speculated [37]. The reduction from Ag + ions to silver nanoparticles (Ag 0 ) with terpenoids may involve the conversion of C–O group of the terpenes to –C–O group [40]. It is also possible that the terpenoids play a role in the reduction of metal ions by oxidation of aldehydic groups in the molecules to carboxylic acids [37].…”

Selective and Sensitive Room Temperature Detection of Ammonia by PPy-Ag Nanocomposite

“…It is similar to pure PPy with positions of the peaks shifted to a higher wavenumber. The shift can be attributed to the coordination of silver with the polymer and over oxidation of PPy [21][22][23]. …”