The paper reports the results of studying the kinetics of DGEBA reactions with maleic anhydride catalyzed by N, N-dimethyl aniline (DMA). This stuffs are used as photoelastic model materials. The origination of monoester was studied separately on a model reaction of maleic anhydride with isopropyl alcohol. The subsequent reaction of epoxy groups with monoester was examined on a system of epoxy ...

OBJECTIVES The aim of this study was to develop a low shrinkage visible light curable nanocomposite dental restorative material without sacrificing the other properties of conventional materials. This nanocomposite was developed by using an epoxy resin 3,4-epoxycyclohexylmethyl-(3,4-epoxy)cyclohexane carboxylate (ERL4221) matrix with 55% wt of 70-100 nm nanosilica fillers through ring-opening p...

Three bioceramic sealers (EndoSequence BC sealer, EndoSeal MTA, and MTA Fillapex) and three epoxy resin-based sealers (AH-Plus, AD Seal, and Radic-Sealer) were tested to evaluate the physicochemical properties: flow, final setting time, radiopacity, dimensional stability, and pH change. The one-way ANOVA and Tukey's post hoc test were used to analyze the data (P = 0.05). The MTA Fillapex sealer...

A lignin-epoxy resin composite was prepared by blending lignin/wood flour with an epoxy resin and polyamine. The effects of the wood flour on the mechanical, thermal creep, and creep recovery properties, as well as the microstructure of the composite, were studied. Among the mechanical properties, the initial modulus increased with increasing content of wood flour. The glass transition temperat...

This work describes flax fibre reinforced polymeric composites with recent developments. The properties of flax fibres, as well as advanced fibre treatments such as mercerization, silane treatment, acylation, peroxide treatment and coatings for the enhancement of flax/matrix incompatibility are presented. The characteristic properties and characterizations of flax composites on various polymers...

the effect of mixing on rheological behavior of 6% wt epoxy-clay nanocomposites was studied. the mixing processes were carried out by low shear mixer, homogenizer and ultrasonic and combination of different mixing techniques at medium and maximum power. all these methods led to intercalated structure. the xrd results showed that the ultrasonic has the best effect on dispersion while a low shear...

Two male workers were acutely intoxicated with gas produced by heating tar epoxy resin paint, and developed peripheral neuropathy. To assess the work atmosphere, we analyzed the degradation products by GC-MS. The major toxic products emitted by heating tar epoxy resin were hydrogen cyanide, phenol, and benzene, as well as naphthalene. From 1 m2 of the surface of steel plates painted with tar ep...

OBJECTIVE To verify the influence of radiopaque fillers on an epoxy resin-based sealer. MATERIAL AND METHODS Experimental sealers were formulated by adding 20%, 40%, 60%, 80%, 100% and 120% of calcium tungstate, ytterbium trifluoride or barium sulphate by weight to an epoxy-resin-base. Setting time, flow, film thickness, radiopacity, sorption, solubility, pH and push-out bond strength were ev...

The use of a diepoxide resin in the form of 1,4-butanediol diglycidyl ether as the epoxy resin, lithium perchlorate (20 wt.%) as the ionic salt, a hardener (4,7,10trioxatridecane-1,13-diamine, 15 wt.%) as the curing agent, and a poling DC electric field of 720 V/m gives an electret that exhibits a maximum voltage of 3.4 V during poling (30 min) and a stabilized voltage of 0.67 V after depoling ...

We present two routes for the fabrication of plasmonic structures based on nanosphere lithography templates. One route makes use of soft-lithography to obtain arrays of epoxy resin hemispheres, which, in a second step, can be coated by metal films. The second uses the hexagonal array of triangular structures, obtained by evaporation of a metal film on top of colloidal crystals, as a mask for re...