Surface modification of alumina with biosafe molecules: Nanostructure, thermal, and mechanical properties of PVA nanocomposites

Abstract

In this investigation, citric acid (CA) and ascorbic acid (AA) as biocompatible and biodegradable coupling agents were grafted onto surface of Al 2 O 3 nanoparticles (NP)s via ultrasonic process. Then, various percentages of the modified Al 2 O 3 NP were immobilized onto matrix of pristine poly(vinyl alcohol) (PVA) and ameliorated their morphology, mechanical and thermal properties. Transmission electron microscopy photographs were valid criterion for characterizing morphology of Al 2 O 3 with CA and AA. The improvement of the mechanical properties revealed good dispersion of the modified Al 2 O 3 into the matrix of PVA. Finally, thermogravimetric analysis curves displayed an increase in the thermal stability of the nanocomposites upon grafting of the modified Al 2 O 3 .

Antimicrobial Bilayer Nanocomposites Based on the Incorporation of As-Synthetized Hollow Zinc Oxide Nanotubes

“…Although the electrospinning process reduces polymer crystallinity, electrospun PVf demonstrated a semi-crystalline nature through the presence of a sharp peak at 2Ɵ = 22.5°, which is characteristic of a monoclinic PV crystal structure [35]. The deposition of this metal oxide over PV nanofibers (sample ZnO-PVf) enhanced this polymer crystallinity, and a new characteristic PV crystalline peak was evidenced at 19.5° [31,35,36]. Probably, the electrospun PV fibers exposition to the ALD chamber temperature (150 °C) and further cooling allowed the reorganization of PV polymeric chains.…”

Employment of ultrasonic waves for the preparation of PVA/TiO2‐BSA nanocomposites: Mechanical, thermal, and optical properties

“…In TGA graph of PVA, the weight loss in region 200°–400° (76.7%) corresponded to dehydration of the PVA which happens after scission and dissociation of the polymer chains. The weight loss before this stage was due to water evaporation and the final weight loss that observed in the range 400–550 °C was due to byproduct which produced from the PVA matrix . As shown in Figure , the thermal behavior of PVA/TiO 2 ‐BSA NCs was developed in the presence of TiO 2 ‐BSA NPs and also according to the Table , the values of T 5 and T 10 (temperature with weight loss of 5 and 10%), residual weight percentage at 800 °C (char yield) and limiting oxygen index (LOI) for PVA NCs with different percentage of TiO 2 ‐BSA were increased in compared to the pure PVA.…”

“…The weight loss before this stage was due to water evaporation and the final weight loss that observed in the range 400-550 8C was due to byproduct which produced from the PVA matrix. 8 As shown in Figure 7, the thermal behavior of PVA/TiO 2 -BSA NCs was developed in the presence of TiO 2 -BSA NPs and also according to the Table II, the values of T 5 and T 10 (temperature with weight loss of 5 and 10%), residual weight percentage at 800 8C (char yield) and limiting oxygen index (LOI) for PVA NCs with different percentage of TiO 2 -BSA were increased in compared to the pure PVA. For example, the obtained values of char yield and LOI for pure PVA were 7 and 20.3, although these values were progressed to 15 and 23.5 for PVA/TiO 2 -BSA NC having 9 wt % of TiO 2 -BSA.…”

“…PVA is prepared via polymerization of vinyl acetate monomers, and the obtained polyvinyl acetate is hydrolyzed to the PVA. Other features of PVA are nonionic, semi‐crystalline, processability, and fantastic ability to being cast …”

“…Other features of PVA are nonionic, semi-crystalline, processability, and fantastic ability to being cast. [8][9][10][11] It is because of special properties that have wide applications in the fields such as packaging film, fuel cells, paper covering, and textile sizing agent. 12 Shehap and coworkers 13 fabricated casting PVA/TiO 2 NC films with different weight percentages by ultrasonic irradiation.…”