Use of Lead (II) Sulfide Nanoparticles as Stabilizer for PMMA Exposed to Gamma Irradiation

Abstract

Lead (II) sulfide (PbS) were synthesized by sonochemical method and crystals with cubic structure exhibit aggregated nanoparticles with size in the range of 50-100 nm. Commercial Poly(methyl methacrylate) (PMMA) containing the PbS nanoparticles (PbS-NP) exposed to gamma irradiation were investigated and both the viscosity-average molar mass (M v ) and degradation index (DI) values were measured. Ours results showed decreases in molar mass when the systems were gamma irradiated, i. e., random scission effects that take place in the main chain. On the other hand, DI results showed that the addition of PbS-NP at 0.3 wt% into the PMMA matrix decreased 100% the number of main chain scissions. Results about the free radical scavenger action of the PbS-NP were obtained by use of 2,2-diphenyl-1-(2,4,6-trinitrophenyl)-hydrazyl radical (DPPH) and are discussed in this study. Analysis of infrared spectra, refraction index, mechanical, and thermal properties showed influence of the PbS-NP in the physical behavior of PMMA.

Effect of MWCNTs Functionalization on Thermal, Electrical, and Ammonia-Sensing Properties of MWCNTs/PMMA and PHB/MWCNTs/PMMA Thin Films Nanocomposites

“…The TGA and dTGA curves for PMMA and MWCNTs(4 wt%)/PMMA nanocomposites are presented in Figure 7 A,B. The derivative thermogravimetric (dTGA) results were acquired by taking the time derivative of the ratio of the sample weight (W) to the initial sample weight (Wₒ), d(W/Wₒ)/dt [ 62 ]. Figure 7 B shows that the complete degradation of PMMA occurs at ≈ 396 °C.…”

“…The second one may correspond to the transfer of radicals tomonomers [ 68 ]. The third peak of thermal decomposition is due to the random scission of the PMMA backbone [ 62 , 69 ]. The peak height increases with an increase in temperature [ 65 ].…”

Electrospun Poly(methyl Methacrylate)/Polyaniline Blend Nanofibres with Enhanced Toxic Gas Sensing at Room Temperature

“…The peak at 2977.29 cm −1 corresponds to the C-H stretching vibrations. 18,19 The intense peak at 1725.90 cm . 20,21 In the FTIR of the blend, a peak at 1699.87 cm −1 is attributed to the COO stretching vibrations confirming the presence of carboxyl group.…”

ZnS Nanocrystals as an Additive for Gamma-Irradiated Poly (Vinyl Chloride)

“…In addition, a decrease in ZnS stabilizing action occurred when its concentration reached 1.00 %wt. This is a rather common effect in polymer-additives systems as optimum additive concentration is overreached 13,14 .…”

“…These extreme transient conditions allow synthesis on the benchtop, at room-temperature conditions, in media that would otherwise require high temperatures, high pressures, or long reaction times 11,12 . Zinc sulfide sonochemical synthesis is a suitable preparation method, which allows fast and simple obtention of morphologically pure products [13][14][15][16][17][18] , circumventing tedious and laborious methods already described in the literature 19,20 . PVC has applications that range from rigid pipes to electron-beam or gamma irradiation sterilizable medical devices..…”