Synthesis and characterization of aramid composites reinforced with silanized graphene platelets.

The synthesis and characterization of aramid composites reinforced with graphene platelets are reported. Hydroxy-functionalised graphene platelets were modified with two sol-gel binders (aminopropyl- or aminophenyl-trialkoxysilanes) and then chemically linked with aramid chains. The effect of the two sol-gel binders on the physiochemical and mechanical properties was evaluated.

Heterogeneous Hybrid Nanocomposite Based on Chitosan/Magnesia Hybrid Films: Ecofriendly and Recyclable Solid Catalysts for Organic Reactions.

Chitosan/magnesia hybrid films (CS-Mg) have been prepared via sol-gel process and employed as heterogeneous catalysts. An in situ generation of a magnesia network in the chitosan matrix was performed through hydrolysis/condensation reactions of magnesium ethoxide. The synthesized hybrid films were characterized using various analytical techniques, such as X-ray photo-electron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM).

Antibiotic resistance and drug modification: Synthesis, characterization and bioactivity of newly modified potent ciprofloxacin derivatives.

Development of new derivatives of commercial antibiotics using different organic reagents and testing these derivatives against different microorganisms are the main goals of this article. Thus, the antibiotic ciprofloxacin, CF, was acylated via reaction with ethyl cyanoacetate and ethyl acetoacetate in basic medium to give the cyanoacetylpiprazinyl dihydroquinoline derivative 3, and oxobutanoylpiprazinyl dihydroquinoline derivative 5, respectively. On the other hand, N-alkylated derivatives 8-10, were prepared through the reaction of CF with chloroacetonitrile, chloroacetyl acetone and chloroacetone in the presence of carbonate salt.

Thermal Mechanical Properties of Graphene Nano-Composites with Kevlar-Nomex Copolymer: A Comparison of the Physical and Chemical Interactions.

This paper reports the preparation of Kevlar-Nomex copolymer nano-composites with exfoliated pristine and functionalized graphene sheets (Grs). The graphene oxide (GrO) platelets were amidized by the reaction of amine-terminated aramid (Ar) with the functional groups present on the GrO surface to prepare the nano-composites films with different loadings of GrO. Chemical changes involved during the oxidation and subsequent amidation were monitored by Raman, FTIR and XP spectroscopic analyses.

Aramid-Zirconia Nanocomposite Coating With Excellent Corrosion Protection of Stainless Steel in Saline Media.

Resistance to stainless steel corrosion in marine-based industries requires more research into materials with an improved surface and enhanced protection by utilizing surface coatings. Herein, a thermally stable aramid-zirconia nanocomposite has been successfully prepared using the sol-gel method to produce a zirconia network-structure bonded to the polymer chain. Using thermal gravimetric analysis (TGA), the residue mass of zirconia retained after the thermal degradation of aramid-zirconia film was determined and found to be 10% by mass.

To what extent do polymeric stabilizers affect nanoparticles characteristics?

Colloidal synthesis of nanoparticles using polymeric stabilizers as a template of a structure directing agent provided a plethora of opportunities in fabricating nanoparticles (NPs) with controlled size, shape, composition and structural characteristics. To understand the complete potency of polymeric stabilizers during the synthesis of nanoparticles, the relationship between polymer characteristics such as structure, molecular weight and concentration and nanoparticles characteristics is discussed in depth. This review portrays the use of polymers to attain nanostructured materials via covalent and non-covalent approaches.

In-Situ Preparation of Aramid-Multiwalled CNT Nano-Composites: Morphology, Thermal Mechanical and Electric Properties.

In this work in-situ polymerization technique has been used to chemically link the functionalized multiwalled carbon nanotubes (CNTs) with aramid matrix chains. Phenylene diamine monomers were reacted in the first stage with the carboxylic acid functionalized CNTs and then amidized in-situ using terephthaloyl chloride generating chemically bonded CNTs with the matrix. Various proportions of the CNTs were used to prepare the hybrid materials.

Controlled Synthesis of ZrO Nanoparticles with Tailored Size, Morphology and Crystal Phases via Organic/Inorganic Hybrid Films.

In this investigation, well defined mesoporous zirconia nanoparticles (ZrO NPs) with cubic, tetragonal or monoclinic pure phase were synthesized via thermal recovery (in air) from chitosan (CS)- or polyvinyl alcohol (PVA)-ZrO hybrid films, prepared using sol-gel processing. This facile preparative method was found to lead to an almost quantitative recovery of the ZrOx content of the film in the form of ZrO NPs. Impacts of the thermal recovery temperature (450, 800 and 1100 °C) and polymer type (natural bio-waste CS or synthetic PVA) used in fabricating the organic/inorganic hybrid films on bulk and surface characteristics of the recovered NPs were probed by means of X-ray diffractometry and photoelectron spectroscopy, FT-IR and Laser Raman spectroscopy, transmission electron and atomic force microscopy, and N sorptiometry.

Non-noble, efficient catalyst of unsupported α-CrO nanoparticles for low temperature CO Oxidation.

Herein, we report the synthesis of chromium oxide nanoparticles, α -CrO NPs, followed by full characterization via XRD, SEM, XPS, and N sorptiometry. The synthesized nanoparticles were tested as catalysts toward the oxidation of CO. The impact of calcination temperature on the catalytic activity was also investigated.

Stabilizing poly(vinyl chloride) using its blends with poly(methyl methacarylate): pyrolysis GC/MS studies.

Binary blends of poly(vinyl chloride) (PVC) with poly(methyl methacarylate) (PMMA) of various compositions were prepared through solution blending. Thermogravimetric and pyrolysis studies of these blends were carried out and the volatile products were separated and quantitatively analyzed by GC/MS. Harmful pyrolysis products from PVC like HCl and different aromatic hydrocarbons are significantly suppressed in presence of a small amount of PMMA.