Epoxy network degradation

Phenolic degradation, thermal and thermo-oxidative, 418-425 Phenolic-epoxy networks, 413 Phenolic monomers, second-order reaction rate constants of formaldehyde with, 403... 

The results show that the crosslinking state and the degradation processes in the epoxy network depend not only on the type of curing agent and the aging regime. The properties of the stainless steel also change these properties within the epoxy interphase at the contact. 

Amine light stabilizer, melamlne-acryllo copolymer degradation, 281-83 Amine-cured epoxy networks cross-link density, 166-67,177-81 structure characterization, 172-73... 

It seems that the addition of epoxy resin improves wet strength for some MDF cements. It was reported that epoxy resin can harden in the presence of hydroxide ions (OIT) from the cement [19] and as consequence, an epoxy network may form, which may decrease degradation. 

Keywords Interlayer adhesion loss Epoxy coatings Weathering Erosion mechanism UV absorber Humidity Water Crosslinking Network degradation Oxygen diffusion and solubility Photoproducts Oxidation zone Rain Lag time UV radiation degradation... 

Decelle, Huet, N., Bellenger, V. Oxidation induced shrinkage for thermally aged epoxy networks, Polymer Degradation and Stability, 81 (2003), p. 239 -248... 

Musto, P., Ragosta, G., Abbate, A., Scarinzi, G. Photo-oxidation of high performance epoxy networks correlation between the molecular mechanisms of degradation and the viscoelastic and mechanical response. Macromolecules 41, 5729-5743 (2008)... 

The degradation of the matrix in a moist environment strongly dominates the material response properties under temperature, humidity, and stress fatigue tests. The intrinsic moisture sensitivity of the epoxy matrices arises directly from the resin chemical structure, such as the presence of hydrophilic polar and hydrogen grouping, as well as from microscopic defects of the network structure, such as heterogeneous crosslinking densities. 

Thermosets consist of a network of interconnected chains whose positions are fixed relative to their neighbors. Such polymers do not flow when heated. Instead, when exposed to high temperatures, thermosets degrade into char. Examples of thermosets include some polyurethanes and epoxy resins. 

The weight loss after the sorption/desorption cycle is 1.3% for the specimens irradiated to 10,000 Mrads. The low weight loss indicates limited degradation. The glass transition temperature should have returned to the value of the unirradiated epoxy (280°C) if degradation products are the only species plasticizing the network. 

One approach to an effective command-destruct epoxy is that of incorporating one or more olefinic bonds into each molecule such that the final network can be degraded by the well-known reaction of olefins with powerful oxidizing agents, such as acidic permanganate ... 

Thermal Stability and Conductivity. Thermal degradation temperature of PMMA, PS, and PVA (poly(vinyl alcohol)) nanocomposites shifts up by 10-100°C. During combustion [179], nanoparticles form a network of char layers that retards the transport of decomposition products. The thermal conductivity of epoxy composites is four times higher than that of the neat epoxy resin with 5 wt% loads. 

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