3-Phase Hierarchical Graphene-based Epoxy Nanocomposite Laminates for Automotive Applications

Two different types of graphene flakes were produced following solution processing methods and dispersed using shear mixing in a bifunctional (A) and a multifunctional (B) epoxy resin at a concentration of 0.8 and 0.6 wt%, respectively. The graphene/epoxy resin mixtures were used to impregnate unidirectional carbon fibre tapes. These prepregs were stacked (seven plies) and cured to produce laminates. The interlaminar fracture toughness (mode-I) of the carbon fiber/graphene epoxy laminates with resin B showed over 56% improvement compared with the laminate without graphene. Single lap joints were prepared using the laminates as adherents and polyurethane adhesives (Sika 7666 and Sika 7888). The addition of graphene improved considerably the adhesion strength from 3.3 to 21 MPa (sample prepared with resin A and Sika 7888) highlighting the potential of graphene as a secondary filler in carbon fibre reinforced polymer composites. Keywords GrapheneCarbon fibre reinforced polymer (CFRP)Fracture toughness; Shear lap joint

Method of Forming Graphene Nanoplatelets, Graphene Nanoplatelets So-Obtained and Composites Comprising Said Nanoplatelets

Provided is a method of forming graphene nanoplatelets, comprising: providing an aqueous suspension comprising expanded graphite; and subjecting the suspension to exfoliation, wherein the exfoliation comprises sequential treatments of sonication and high shear mixing, thereby forming graphene nanoplatelets. Also provided is a method of forming an expanded graphite, comprising obtaining an expandable graphite and heating the expandable graphite in flowing gas at a temperature of at least 600°C. Also provided are graphene nanoplatelets obtainable or obtained by the said method of forming graphene nanoplatelets, a plastics composite comprising the graphene nanoplatelets, a vehicle or structure comprising such a composite, and use of such graphene nanoplatelets in a plastics composite

Let there be water: How hydration/dehydration reactions accompany key Earth and life processes

Water plays a key role in shaping our planet and making life possible. Given the abundance of water on Earth's surface and in its interior, chemical reactions involving water, namely hydration and dehydration reactions, feature prominently in nature and are critical to the complex set of geochemical and biochemical reactions that make our planet unique. This paper highlights some fundamental aspects of hydration and dehydration reactions in the solid Earth, biology, and man-made materials, as well as their connections to carbon cycling on our planet