Thermodegradation kinetics of epoxy/DDS/POSS system

Abstract

The thermodegradation kinetics of a hybrid inorganicorganic epoxy system formed by diglycidyl ether of bisphenol A, DGEBA/DDS, modified with octahedral oligomeric silsesquioxane, octa(aminopropylsilsesquioxane) was studied. The average activation energy of thermodegradation of this system was calculated by the integral method developed by Flynn-Wall-Ozawa (E 5 105.01 kJ mol 21 ) and by Coats and Redfern method (E 5 113.07 kJ mol 21 ). Lifetime and half-life time of the materials system were predicted using the kinetic parameters. The results obtained from the two methods accorded well with each other. POLYM. COMPOS.,

Effect of the elastomer type on the microstructure and mechanical properties of polypropylene

“…Barral et al [15] pointed to a long lifetimes at room temperature in systems containing the hybrid POSS through the calculations on lifetime related to thermal degradation. Montero et al [16] observed that the epoxy/amine system followed a first‐order degradation mechanism, F 1 , corroborating the results obtained by Villanueva et al [13] and Zhang et al [14]. However, for ∼50% of the degradation, the mechanism shifted to the diffusion mechanism after the POSS incorporation.…”

“…The authors have also noted that the nanocomposites containing POSS showed, in general, activation energies that were greater than that of the neat epoxy resin for different kinetic methods. Zhang et al [14] showed that the addition of POSS alternated the kinetic mechanism from F 1 (neat epoxy) to the nucleation and growth mechanism ( A 2 ). Also, they observed an increase in the activation energy of the hybrid materials containing POSS.…”

Thermal decomposition of a honeycomb-network sheet: A molecular dynamics simulation study

“…It has been investigated recently by Barnard and Snook [33] using ab initio quantum mechanical techniques whereby it was noted that the problems "has been overlooked by most computational and theoretical studies". Many of these studies can be viewed in a broader context as part of the problem of thermal decomposition of gels [34], epoxy resins [35,36] and other 3D networks, studied both experimentally [34][35][36], and by means of simulations [37] as in the case of Poly-dimethylsiloxane (PDMS). In most of these cases, however, mainly a stability analysis is carried out whereas still little is known regarding the collective mechanism of degradation, the dependence of rupture time on system size, as well as the decomposition kinetics, es-pecially as far as (2D) polymer network sheets are concerned.…”

Force-induced breakdown of flexible polymerized membrane

“…A number of studies based on continuum [9], percolation [10][11][12], or molecular level [13][14][15] considerations of the mechanical breakdown of this network, modeled as a triangular lattice of spectrin tetramers, have been reported so far. Many of these studies can be viewed in a broader context as part of the problem of thermal decomposition of gels [16], epoxy resins [17,18] and other 3D networks both experimentally [16][17][18] and by means of simulations [19] in the case of poly-dimethylsiloxane (PDMS).…”