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Introduction Epoxy resins are very used thermoset polymers because of their good combination of high elastic modulus and mechanical strength and good chemical and thermal resistance. One of their main limitations, the low

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Introduction Epoxy resin, one of the most coveted resins used in the manufacture of composite materials, undergoes curing reaction exothermically [ 1 – 14 ]. The very exothermic nature of epoxy curing system makes it difficult

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epoxy carbon fiber composites. Their flammability behaviors were investigated by cone calorimeter. The thermo-oxidation stability and low gas permeability of buckypapers or CNF nanofiber are key roles in improving flame-retardant properties of composites

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like Tokamaks [ 1 ]. CE resins have been receiving increasingly importance because of their enhanced temperature and radiation resistance compared to conventional epoxy resins. They are envisaged to experience fast neutron fluence up to 1 × 10 22 m −2

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Abstract  

Coir-fiber-based fire retardant nano filler has been developed for epoxy resin (ER). At first, the coir fiber was brominated with saturated bromine water and then treated with stannous chloride solution. After drying, it was grinded to nano dimension and mix well with ER for composites preparations. FTIR, DSC, and TG techniques were used to characterize the brominated coir fiber. Gravimetric analysis shows only 10% by mass of bromination on coir fiber. Bromination decreases the thermal stability of the coir fiber, but it does not affect the final stability of the composites. This study concentrates on the thermal, fire retardant, and morphological properties of nanocomposites prepared by direct mixing. The fire retardancy properties (smoke density and limiting oxygen index) of coir–epoxy nanocomposites have increased significantly.

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Abstract  

The rheological behaviour of the materials diglycidil ether of bisphenol A (n = 0), 1, 2 diamine-cyclohexane and the epoxy reactive diluent vinylcyclohexane dioxide have been studied both separately and mixed before the beginning of the curing reaction. Different kinds of tests such as: preshear and time sweep, flow curve and stress sweep experiments were carried out. From these experiments, interesting information about: viscosity-shear stress and viscosity-shear rate dependences, storage modulus and the linear viscoelastic region were found out. Relationships between concentration of diluent and the final viscosity of the mixed sample and also between percentage of diluent and storage modulus were studied.

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residual stress analysis [ 4 ]. Electrically conductive adhesives consist of a polymer binder that provides mechanical strength and conductive fillers, which offer electrical conduction. Polymers are commonly classified as either thermosets (such as epoxies

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Abstract  

We have used molecular simulations to study the properties of nanocomposites formed by the chemical incorporation of polyhedral oligomeric silsesquioxane (POSS) particles in the cross-linked epoxy network. The particular POSS molecule chosen—glycidyloxypropyl-heptaphenyl POSS—can form only one bond with the cross-linker and thus was present as a dangling unit in the network. Four epoxy-POSS nanocomposites containing different fractions (up to 30 mass/%) of POSS particles were studied in this work. Well-relaxed atomistic model structures of the nanocomposites were created and then molecular dynamics simulations were used to characterize the density, glass transition temperature (T g), and the coefficient of volume thermal expansion (CVTE) of the systems. In addition to the effect of nanoparticle loading, the effect of nanoparticle chemistry on the nanocomposite properties was also characterized by comparing these results with our previous results (Lin and Khare, Macromolecules 42:4319–4327, 2009) on neat cross-linked epoxy and a nanocomposite containing a POSS nanoparticle that formed eight bonds with the cross-linked network. Our results showed that incorporation of these monofunctional POSS particles into cross-linked epoxy does not cause a measurable change in its density, glass transition temperature, or the CVTE. Furthermore, simulation results were used to characterize the aggregation of POSS particles in the system. The nanofiller particles in systems containing 11, 20, and 30 mass/% POSS were found to form small clusters. The cluster-size distribution of nanoparticles was also characterized for these systems.

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Abstract  

This article aims to modify conventional epoxy resin by blending with four different Mannich base oligomers. These oligomers are similar to phenolic resin matrix and simultaneously function as amino curing agent for epoxy matrix. In this context, Mannich base oligomers were prepared, respectively, by Mannich polycondensation reaction of four phenols namely phenol, m-cresol, resorcinol and 1,5-dihydroxy naphthalene, respectively, with formaldehyde and piperazine in presence of acid catalyst. The resulting oligomers were characterized by elemental analysis, spectral studies (IR and NMR), number average molecular mass
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estimated by non-aqueous conductometric titration and thermal stability by thermogravimetric analysis (TG). Each of these oligomers was used in resin matrix as a blending component for the modification of commercial epoxy resin for fabricating glass fibre reinforced laminates. Finally, these laminates were evaluated for their synergetic thermal stability, mechanical properties and chemical resistance to different reagents.
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Thermal analysis characterization of isosorbide-containing thermosets

Isosorbide epoxy as BPA replacement for thermosets industry

Journal of Thermal Analysis and Calorimetry
Authors: Xianhong Feng, Anthony East, Willis Hammond, Zohar Ophir, Yi Zhang, and Michael Jaffe

thermosets and thermoplastics. BPA-based epoxies are manufactured for plastic lining of cans used for food, polycarbonate baby bottles, and tableware; white dental fillings; and sealants [ 14 ]. The growing global production of BPA not only puts the burden on

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