Preparation, Characterization and Photostability of Nanocomposite Films Based on Poly(acrylic acid) and Montmorillonite

Abstract

Polyacrylic acid (PAA)/clay mineral (SWy-1) nanocomposites were prepared by intercalation in solution and their photostability was evaluated. For the nanocomposite films containing 5, 10 and 20 wt % in SWy-1 mass occurred intercalation along with some clay exfoliation, while for PAA/30%SWy-1, the intercalation of PAA chains into the clay interlayers was observed. Scanning Electron Microscopy (SEM) images of the films suggested that nanocomposite films are homogeneous, indicating efficient dispersion of the polymer matrix into the SWy-1 clay. The thermal degradation temperatures of depolymerisation for the nanocomposite films were higher (362-370 °C) than pure PAA (361 °C), which means that the presence of SWy-1 clay promotes thermal stabilization.The photooxidative degradation of pure PAA and nanocomposite films was followed using Size Exclusion Chromatography (SEC). The degradation rate constant for pure PAA was higher than nanocomposite films; therefore, the increase of SWy-1concentration detained the degradation of PAA. The presence of SWy-1 clay contributes for the photostabilization of the material. SWy-1 has ability to disperse the incident light as well as also to absorb part of the UV light instead of PAA, hence minimizing the degradation rate.

Vapor Deposition of Transparent Antifogging Polymeric Nanocoatings

“…The spectra have absorptions unique to each comonomer, indicating that both monomers are incorporated into the as-deposited film. The presence of AA is confirmed by the presence of broad OH stretching of the COOH functional group in the range from 3650 to 2200 cm –1 . The other important vibrational modes are symmetric stretching of C–H (3000–2800 cm –1 ), C–H bending (1600–1350 cm –1 ), and C–O stretching (1300–1100 cm –1 ).…”

“…The presence of AA is confirmed by the presence of broad OH stretching of the COOH functional group in the range from 3650 to 2200 cm −1 . 38 The other important vibrational modes are symmetric stretching of C−H (3000−2800 cm −1 ), C−H bending (1600−1350 cm −1 ), and C−O stretching (1300− 1100 cm −1 ). The stretching vibration of the carbonyl group (CO), which is a clear fingerprint of acrylate functionality, is centered between 1703 and 1725 cm −1 , the value of which changes with the composition of the coating.…”

Mechanically stable membranes of polyacrylic acid‐grafted chitosan‐functionalized carbon nanotubes with remarkable water storage capacity in sandy soils

“…The TGA measurement of PAA/CS/MWCNTs composite (Figure 6b) confirmed the CS grafting yield onto MWCNTs and indicated a loading of 14 wt% for PAA. The TGA analysis also indicted how the PAA/CS/MWCNTs composite is thermally stable 61,62 …”

“…The TGA analysis also indicted how the PAA/CS/MWCNTs composite is thermally stable. 61,62 Notably, the polymer grafting process showed a pronounced impact on MWCNT dissolution (see Figure 7). As seen, pristine MWCNT showed a poor dissolution even after a sever ultrasonic agitation.…”

Biodegradable Compounds of Poly (Ɛ-Caprolactone)/Montmorillonite Clays

“…Methods used to obtain these compatibilizers include chemical modification of non-polar polymers with monomers by reactive processing, such as maleic anhydride (MA). 10,11 Grafting with maleic anhydride is intended to achieve compatibility between polymers in blends or between filler and polymer in composites or nanocomposites. Reactions are usually performed in presence of organic peroxides and can take place in solid, melt or solution states.…”