The correlation between the mechanical properties of Fillers/Epoxy composites and their tribological behavior was investigated. Tensile, hardness, wear, and friction tests were conducted for Neat Epoxy (NE), Graphite/Epoxy composites (GE), and Data Palm Fiber/Epoxy with or without Graphite composites (GFE and FE). The correlation was made between the tensile strength, the modulus of elasticity,...

Eight new withanolides were isolated from the aerial parts of Vassobia lorentzii and characterized by spectroscopic methods and with the aid of molecular modeling. The compounds were identified as (17S,20R,22R)-5beta,6beta:18,20-diepoxy-18-hydro xy-1-oxowitha-2,5, 24-trienolide (1); (17S,20R,22R)-18,20-epoxy-4beta, 18-dihydroxy-1-oxowitha-2,5,24-trienolide (2); (17S,18R,20R, 22R)-4beta-hydroxy-...

This work involves the development of a novel siliconized epoxy interpenetrating coating system using epoxy resin as base, hydroxylterminated polydimethylsiloxane (HTPDMS) as modifier, -aminopropyltriethoxysilane ( -APS) as crosslinking agent and dibutyltindilaurate (DBTDL) as catalyst. Polyamidoamine and aromatic polyamine adduct were used as curing agents for the above coating systems. The th...

In this article we introduce and compare three techniques for low-cost and rapid bonding of stereolithographically structured epoxy components to polydimethylsiloxane (PDMS). In short, we first create a polysiloxane layer on the epoxy surface via silane surface coupling and polymerization. Afterwards, the modified epoxy surface can be bonded to a PDMS component at room temperature using a handh...

This research describes the effects of shear flow-induced alignment of dispersed single-walled carbon nanotubes in viscous polymer solutions and the application of this alignment strategy to produce epoxy-based composites with superior mechanical properties. Previously, it was shown that the use of an anionic surfactant (i.e. sodium dodecylbenzene sulfonate, NaDDBS) in conjunction with a weakly...

High temperatures caused by partial discharge results in the decomposition of insulating epoxy resins in electrical equipment. In this paper, the ReaxFF force field is used to investigate the decomposition process of epoxy resins cured by anhydride and the formation mechanisms of small-molecule gases. Results show that the initiation reaction is the cleavage of an ester bond linked with an epox...

Heat generation in an exothermic reaction during the curing process and low thermal conductivity of the epoxy resin produces high peak temperature and temperature gradients which result in internal and residual stresses, especially in large epoxy samples. In this paper, an optimization algorithm was developed and applied to predict the thermal cure cycle to minimize the temperature peak and the...

costs and train operations. The impact is sometimes magnified by imperfect or poorly understood techniques for predicting and detecting IJ failures. A common factor in many failures of bonded IJs is a tendency for the epoxy to come debonded from the rail or joint bar near the center of the joint (2). The debonded region starts small but grows with time and traffic, spreading outward toward the ...

Novel self-repairing Urea-Phenol-Formaldehyde (UPF) microcapsules containing linseed oil were prepared via in-situ polymerization in an oil-in-water emulsion. The main purpose of encapsulation is to control the release of linseed oil, when external conditions such as mechanical stress or energy cause microcapsules to break. These controlled release mechanisms of linseed oil make them suitable f...

Functionalization of single-walled carbon nanotubes (SWNTs) with covalently grafted amine moieties provides reactive fillers with potential covalent anchoring to an epoxy matrix. Manufacturing and characterization of a high performance epoxy system reinforced with as-grown and aminated SWNTs are presented through four different approaches. Epoxy composite materials incorporating SWNTs aminated ...