A convergent biomimetic synthesis of hemibrevetoxin B from d-glucal and d-arabinose utilizes an electrophile-promoted cascade anti-Baldwin cyclization of an epoxy alcohol. The epoxy alcohol arises from a palladium-catalyzed coupling of a highly functionalized organozinc compound and an alkenyl iodide, which serve as two chiral building blocks of similar size and complexity. This first successfu...

Copyright © Korean Carbon Society http://carbonlett.org Abstract The use of carbon nanotubes (CNTs) as a reinforcing material in a polymer matrix has increased in various industries. In this study, the flexural behavior of CNT-modified epoxy/ basalt (CNT/epoxy/basalt) composites is investigated. The effects of CNT modification with silane on the flexural properties of CNT/epoxy/basalt composite...

Epoxy powder coatings containing zinc aluminum phosphate (ZAP) and zinc phosphate (ZP), which are the 2nd and 1st generation of phosphate-based pigments respectively, were applied to the surface of mild steel sheets. The anticorrosive performances of the coated samples were studied using electrochemical impedance spectroscopy (EIS). Cathodic disbonding resistance and the adhesion performance of...

The epoxy/glass fiber/organo-montmorillonite (OMMT) nanocomposites were prepared by hand lay up method. In the previous work, the flexural and morphological properties of the epoxy/glass fiber/OMMT were studied. In this work, the epoxy nanocomposites were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and water absorption tests. The exfoliation of OMMT in epox...

A well-dispersed phase of exfoliated graphene oxide (GO) nanosheets was initially prepared in water. This was concentrated by centrifugation and was mixed with a liquid epoxy resin. The remaining water was removed by evaporation, leaving a GO dispersion in epoxy resin. A stoichiometric amount of an anhydride curing agent was added to this epoxy-resin mixture containing the GO nanosheets, which ...

in recent years many research works have been carried out on anti-corrosive nanocomposites coatings containing mineral reinforcements. the most important criteria in these attempts are polymerization method and the type of matrix and reinforcement of nanocomposites. in this regard, the physical and mechanical properties of the polymers in which a small amount of filler is used can be improved. ...

The sol-gel technique was used to prepare epoxy/silica nano-hybrids. The thermal characteristics, curing kinetics and structure of epoxy/silica nano-hybrids were studied using differential scanning calorimetry (DSC), 29Si nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM). To improve the compatibility between the organic and inorganic phases, a coupling agent was used t...

Concrete-epoxy interface can be found in many strengthened or retrofitted structures, especially in Hong Kong where concrete structures are the majority. In practice, epoxy is usually used in repairing concrete structures because of its excellent adhesion, chemical and heat resistance, good mechanical properties and electrical insulating properties. The bond between concrete and epoxy has been ...

A novel method for preparing epoxy/silver nanocomposites was developed via the in situ formation of silver nanoparticles (AgNPs) within the epoxy resin matrix while using silver nanowires (AgNWs) as a conductive filler. The silver–imidazole complex was synthesized from silver acetate (AgAc) and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole (imidazole). AgNPs were generated in situ during the curin...

Epoxy resins have been widely used in commercial applications, and their adverse health effects have been mostly reported in occupational settings. The most frequent adverse effects are irritation or allergic mechanisms involving the dermal and respiratory systems. Sensitization is usually caused by low molecular weight or short-chain compounds. We report here two workers exposed to an epoxy re...