Reinforcement contribution of cellulose nanocrystals (CNCs) to tensile properties and fracture behavior of triaxial E-glass fabric/epoxy composites

Contribution of the Surface Treatment of Nanofibrillated Cellulose on the Properties of Bio-Based Epoxy Nanocomposites Intended for Flexible Electronics

“…The microstructure of the cured neat epoxy matrix shows a brittle behavior in liquid nitrogen with a completely smooth and flat surface and evidence of branched river-like fracture propagation ( Figure 8 ) [ 38 ]. Contrarily, the epoxy nanocomposites showed remarkably different fracture microstructures ( Figure 8 ).…”

“…Contrarily, the epoxy nanocomposites showed remarkably different fracture microstructures ( Figure 8 ). Thus, the fracture surface of all nanocomposites was rough, with a leaf-like uniform pattern consisting of both crack-deflections and stress-whitening areas, with the latter being responsible for the restriction of fracture growth through the epoxy matrix ( Figure 8 ) [ 38 ]. No pulled out NCs or voids were detected on the nanocomposite surface micrographs, revealing a good interfacial adhesion with the epoxy matrix.…”

“…Nevertheless, a distinct morphology was noticed in the case of E/NC/SM nanocomposite, probably due to the presence of poly(metacrylic acid) on the NCs surface which led to an increased interface volume and compatibility with the epoxy matrix [ 63 ]. Additionally, this sample showed a large number of stress-whitening zones due to the plastic deformation of the epoxy matrix around the SM grafted NCs [ 38 ]. Indeed, the nanocomposite containing NC/SM showed the best thermal and thermo-mechanical properties, thus confirming this observation.…”

“…NC has been intensively studied as a reinforcing agent in bio-based polymers such as poly(lactic acid) [ 28 , 29 ], polyhydroxyalkanoates [ 30 , 31 ], poly(butylene succinate) [ 32 ], and starch [ 33 , 34 ], leading to fully-biobased materials with improved mechanical properties and, in some cases, with better thermal properties. However, a smaller number of studies were dedicated to the reinforcement of common epoxy resins with cellulose nanocrystals or nanofibers [ 17 , 35 , 36 , 37 , 38 ]. One problem in the case of nanocomposites based on hydrophobic polymer matrices and hydrophilic fillers is the weak interaction at the interface that leads to the poor dispersion of the nanofiller [ 37 ].…”

Effect of Polyethylene-Grafted Maleic Anhydride on the Properties of Flue-Gas Desulfurized Gypsum/Epoxy Resin Composites

“…The excessive addition of PGM likely caused the aggregation, which led to the poor dispersion of FGD gypsum. When subjected to stress, the blend of calcium sulfate hemihydrate and PGM acted as stress concentrators; this phenomenon was followed by the formation of a triaxial stress field surrounding the blend of calcium sulfate hemihydrate and PGM, which further led to the formation of cavities via blend debonding or blend cavitation [24]. These cavities relieved the stress in front of the crack tip, which allowed the composite cavities to grow and enhance the mechanical properties of the composites [25].…”