Synergistic Effect of Functionalized Nanokaolin Decorated MWCNTs on the Performance of Cellulose Acetate (CA) Membranes Spectacular

Development of Versatile, thermally stable, flexible, UV-resistant and antibacterial polyvinyl alcohol-Nanodiamonds composite for efficient food packaging

This research paper reports an enhancement of thermal, optical, mechanical and antibacterial activities of the Polyvinyl alcohol-Nanodiamonds (PVA-NDs) composite required for the food packaging industry. The synthesis of composites was done by the wet processing method. The large surface area of NDs facilitated the robust interaction between the hydroxyl group and macromolecular chains of PVA to enhance the hydrogen bonding of PVA with NDs rather than PVA molecules. Thus, a reduction in PVA diffraction peak intensity was reported. NDs improved the thermal stability by preventing the out-diffusion of volatile decomposition products of PVA. The results also revealed an enhancement in tensile strength (∼60 MPa) and ductility (∼180 %). PVA-NDs composite efficiently blocked the UVC (100 %), most of the part of the UVB (∼85 % above 300 nm), and UVA (∼58 %). Furthermore, enhanced antibacterial activities were reported for PVA-NDs composite against E. coli and S. aureus. NDs accumulated around the bacterial cells prevented essential cellular functions and led to death. Hence, this composite could be a promising candidate for safe, thermally stable, strong, flexible, transparent, UV- resistant antibacterial food packaging material.

Reinforcement of single-walled carbon nanotubes on polydimethylsiloxane membranes for CO2, O2, and N2 permeability/selectivity

In this study, PDMS incorporated with SWCNTs have been fabricated via solution casting method for industrial applications and characterized by the analyses of SEM, FTIR, TGA, AFM, and MST. The modified membranes were further analyzed for CO₂, O₂, and N₂ gas permeability. The strategic membranes have five different weight ratios (0.013, 0.025, 0.038, 0.050, 0.063) compared to neat PDMS membranes. The even distribution of SWCNTs in PDMS provided results that showed improvement in thermal stability. However, mechanical strength has been weakened with increased concentration of nanofiller because of the increase in the number of SWCNTs by increases that imperfections become more severe. The designed polymeric membranes with good thermal stability and adequate mechanical strength can be used for the selectivity and permeability of CO₂, O₂, and N₂ gases. The effect of the PDMS-SWCNTs on gas permeability has been studied. 0.063 wt.% SWCNTs presented the maximum permeability of CO₂ gas while maximum O₂ and N₂ gas permeability have been obtained by 0.013 wt.% SWCNTs. The ideal selectivity of mixed (50:50) gas conditions has been tested. The maximum CO₂/N₂ ideal selectivity was obtained by 0.050 and 0.063 wt.% SWCNTs while maximum O₂/N₂ ideal selectivity obtained by 0.050 wt.% SWCNTs. Therefore, the fabrication of this novel SWCNTs-PDMS membrane may lead to separating the industrial exhaust and be used as a potential membrane for environmental remediation in the future.

A functional cobalt-organic framework constructed by triphenylamine tricarboxylate: Detect nitroaromatics by fluorescence sensing and UV-shielding

Luminescent metal-organic frameworks (LMOF) with ligand-modified are a promising strategy to be applied to fabricate chemical sensors. Herein, a novel Co (II) metal-organic framework (Co-MOF), namely Co [(NTB) bpy] (NTB = 4,4'4″-tricarboxylic acid triphenylamine, bpy = 4,4 '-bipyridyl), was successfully synthesized with excellent water stability and fluorescence properties. Due to the propeller structure of NTB ligands, a special topological structure of Co-MOF was shown: {2⁴.4¹⁶.6⁸}{2}4. It was proved that Co-MOF has great stability by soaking in different solvents for two weeks. Remarkably, the fluorescence quenching experiment verified that Co-MOF has excellent fluorescence sensor performance. Trinitrophenol, 2,4-dinitrophenol, and 2-amino-4-nitrotoluene (10^-5 M) with LOD of 9.00 × 10^-5, 5.40 × 10^-5 and 5.07 × 10^-6 M can be detected via the process of fluorescence enhancement and quenching. Throughout the investigation, the mechanics of fluorescence quenching was performed. Due to the excellent UV absorption capacity of Co-MOF, it was a promising application to combine low-dimensional nanomaterials with sustainable biomass materials. A hybrid films of Co-MOF and cellulose acetate (CA) was generated. The hybrid films had highly transparency in the visible wavelength range and excellent UV-shielding ability owing to the CA/Co-MOF hybrid films enhanced the UV absorption capacity of Co-MOF.

Idiosyncratic cellulose acetate nanocomposite membranes: synthesis and performance control study for desalination

In order to enhance the characteristic performance of cellulose acetate (CA) membranes, a novel nanofiller synergy is adopted herein for desalination purpose. Activated zinc oxide and aero-silica synergy in seven different ratio based combinations were introduced into CA matrix adopting solution mixing technique. The functionalized nanofillers loading impact on membranes surface texture, crystalline structural difference, functional groups presence, thermal decomposition and phase transition temperatures were scrutinized. The sole membranes were practically employed to determine salts (NaCl and MgCl₂) rejection tested by dead-end filtration system. Time dependent flux rate and fouling study were performed to decide the reuseability of nanocomposite membranes. The results validate a remarkable improvement by idiosyncratically synthesized nanocomposite membranes.