Thermal aging kinetic and effects on mechanical behavior of fully recycled composite based on polypropylene/polyethylene blend

Abstract

The effect of thermal oxidation of a fully recycled carbon fibers reinforced stabilized polypropylene/polyethylene blend on the mechanical properties has been studied at 120, 130 and 140 °C. In a first step, several analyses by FTIR and UV spectrometry and differential scanning calorimetry were performed in order to detect and monitor the evolution of the antioxidants and oxidation products in the materials. This approach aims to well understand and identify the aging mechanisms that will be modeled in a second step in a kinetic model capable of predicting the evolution of carbonyl build‐up while taking into account the presence of the different antioxidants. Modeling results showed a good correlation between the kinetic behavior and the obtained experimental data. Furthermore, the effect of thermal aging on the mechanical behaviors of the composite and the matrix were studied at the macroscopic scale at different strain rates. It has been shown that the thermal oxidation affects only the elongation at break. The numerical values of the oxidation products generated by the kinetic model allowed linking the evolution of the mechanical behavior under aging with the physicochemical state of the material. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46640.

Thermal aging influence on the damage mechanisms of fully recycled composite‐reinforced polypropylene/polyethylene blend

“…This mechanic behavior was characterized through tensile tests at quasi‐static loading (10 −2 s −1 ) on composite specimens taken at different time of aging. These results were obtained in previous work and it has been proven that with the increase of the exposure time, only the elongation at break is affected. Figure shows that from the first moments of exposure (during the induction period) the elongation at break for quasi‐static tensile tests drops dramatically by 45%.…”

“…In previous work , a kinetic model based on a standard mechanistic scheme was proposed to predict the carbonyl build‐up evolution and the antioxidants disseverance in the composite and its matrix at the different temperatures of exposure. This model is also capable of determining low values of the oxidation products, [CO], at the induction period so a link is directly made between the mechanical properties affected by the aging (elongation at break Fig.…”

Failure analysis of fiber-reinforced composites subjected to coupled thermo-mechanical loading

“…Studies on coupled thermo-mechanical responses of materials, which play an important role in structural health monitoring and optimal design of composites, have attracted great interests from both engineers and academic researchers [5][6][7]. Discussions on the effects of thermal stresses [8][9], thermal aging [10][11][12], sintering temperature [13] and thermal expansion [14] on the properties of composite materials have been reported by many investigators. Based on the scanning electron microscope (SEM) micrographs, Li et al [15] studied the failure mechanisms of composite materials at room and elevated temperatures.…”

Composições formadas por polipropileno reciclado e resíduos de couro wet-blue: uma prática sustentável

“…Thus, the environmental concern with the generation of waste has contributed to its use in the creation of new products (AL-FAKIH et al, 2019;FERNANDES et al, 2017;SILVA et al, 2017). Innovative solutions must be focused on the best product performance, such as durability and income generation with cleaner production, in order to create new consumer behavior (TAMBOURA et al, 2018;WANG et al, 2018;ALMEIDA et al, 2017).…”