Thermo-Mechanical Performance of Epoxy Hybrid System Based on Carbon Nanotubes and Graphene Nanoparticles.

This study focuses on epoxy hybrid systems prepared by incorporating multi-wall carbon nanotubes (MWCNTs) and graphene nanosheets (GNs) at two fixed filler amounts: below (0.1 wt%) and above (0.5 wt%), with varying MWCNT:GN mix ratios.

Rheological, Thermal and Mechanical Characterization of Toughened Self-Healing Supramolecular Resins, Based on Hydrogen Bonding.

This paper proposes the design of toughened self-healing supramolecular resins able to fulfill functional and structural requirements for industrial applications. These new nanocomposites are based on compounds acting as promotors of reversible self-healing interactions. Electrically conductive carbon nanotubes, selected among those allowing to reach the electrical percolation threshold (EPT) with a very low amount of nanofiller, were dispersed in the self-healing polymeric matrix to contrast the electrical insulating properties of epoxy matrices, as required for many applications.

Dielectric Spectroscopy and Thermal Properties of Poly(lactic) Acid Reinforced with Carbon-Based Particles: Experimental Study and Design Theory.

In the present study, polylactic acid (PLA) enriched with carbonaceous particles like multi-walled carbon nanotubes (MWCNTs), graphene nanoplates (GNPs) or a combination of both up 12 wt % of loading are used for producing 3D-printed specimens with fused deposition modeling (FDM) technology which are then experimentally and theoretically investigated. The goal is to propose a non-conventional filaments indicated for additive manufacturing process with improved dielectric and thermal properties, compared to the performances exhibited by the unfilled polymer. In the light of the above, a wide dielectric spectroscopy and a thermal analysis, supported by a morphological investigation, are performed.

Rheological and Morphological Properties of Non-Covalently Functionalized Graphene-Based Structural Epoxy Resins with Intrinsic Electrical Conductivity and Thermal Stability.

In this paper, a non-covalent π-π interaction between graphene nanoparticles (G) and a pyrene-based molecule (py) has been successfully accomplished to give the functionalized nanofillers (G-py). The proposed modification has proven to be a winning solution aimed at safeguarding the graphene's notable electronic properties, while promoting a more effective nanofiller dispersion attributable to a decrease in viscosity with consequent improvement of the rheological properties of the formulated nanocomposites filled with G-py. The electrical current maps of the G-py based epoxy composites, loaded with filler weight percentages both above and below the electric percolation threshold (EPT), were obtained by tunneling atomic force microscopy (TUNA) technique.

Microwave Treatments of Cereals: Effects on Thermophysical and Parenchymal-Related Properties.

Dielectric heating is one of the most interesting techniques for pest disinfestation. However, most of the literature works give information about the ability of microwave treatments at different power-time conditions to kill insects; less is given about the analysis of matrices structural properties and heat transport. Accordingly, the aim of this work is to investigate the effect of microwave treatments, applied for pest disinfestation, on heat transport behavior and physical/structural properties, such as water uptake capability, mineral losses, texture change, and germination capability, of most consumed cereals in human diet, such as weak wheat, durum wheat, and corn.

Multifunctionality of structural nanohybrids: the crucial role of carbon nanotube covalent and non-covalent functionalization in enabling high thermal, mechanical and self-healing performance.

This study proposes new kinds of functionalization procedures able to preserve specific properties of carbon nanotubes (CNTs) and to improve compatibility with the epoxy matrix. Through a covalent approach, for the first time, CNTs are functionalized with the same hardener agent, 4,4'-diaminodiphenyl sulfone, employed to solidify the epoxy matrix and capable to fulfill mechanical requirements of industrial structural resins. The same CNTs are non-covalently modified through the polymer wrapping mechanism with benzoxazine (Bz) terminated polydimethylsiloxane (PDMS).

Reversible Self-Healing Carbon-Based Nanocomposites for Structural Applications.

Reversible Hydrogen Bonds (RHB) have been explored to confer self-healing function to multifunctional nanocomposites. This study has been carried out through a sequence of different steps. Hydrogen bonding moieties, with the intrinsic ability to simultaneously perform the functions of both hydrogen donors and acceptors, have been covalently attached to the walls of carbon nanotubes.

UV Irradiated Graphene-Based Nanocomposites: Change in the Mechanical Properties by Local HarmoniX Atomic Force Microscopy Detection.

Epoxy based coatings are susceptible to ultra violet (UV) damage and their durability can be significantly reduced in outdoor environments. This paper highlights a relevant property of graphene-based nanoparticles: Graphene Nanoplatelets (GNPs) incorporated in an epoxy-based free-standing film determine a strong decrease of the mechanical damages caused by UV irradiation. The effects of UV light on the morphology and mechanical properties of the solidified nanocharged epoxy films are investigated by Atomic Force Microscopy (AFM), in the acquisition mode "HarmoniX.

On the relevance of thermophysical characterization in the microwave treatment of legumes.

This study is focused on the characterization of the thermal behavior and physical properties of the most consumed legumes in the daily diet such as beans, lentils and chickpeas. Because of a lack of information in the literature about the effect of microwave treatments on legumes, characterization protocols have been applied before and after subjecting them to microwave irradiation suitable for pest disinfestation. The effects of two different radiative treatments, one suitable for inactivating the infesting fauna and the other simulating uncontrolled treatments, characterized by very high temperatures, were tested.

Toughening of Epoxy Adhesives by Combined Interaction of Carbon Nanotubes and Silsesquioxanes.

The extensive use of adhesives in many structural applications in the transport industry and particularly in the aeronautic field is due to numerous advantages of bonded joints. However, still many researchers are working to enhance the mechanical properties and rheological performance of adhesives by using nanoadditives. In this study the effect of the addition of Multi-Wall Carbon Nanotubes (MWCNTs) with Polyhedral Oligomeric Silsesquioxane (POSS) compounds, either Glycidyl Oligomeric Silsesquioxanes (GPOSS) or DodecaPhenyl Oligomeric Silsesquioxanes (DPHPOSS) to Tetraglycidyl Methylene Dianiline (TGMDA) epoxy formulation, was investigated.

Nano-Charged Polypropylene Application: Realistic Perspectives for Enhancing Durability.

Isotactic polypropylene/multi-walled carbon nanotube (iPP/MWCNTs) films have been exposed to accelerated weathering in a UV device for increasing times. The effect of UV irradiation on the structural and chemical changes has been investigated. The resistance to accelerated photooxidation of (iPP/MWCNTs) films has been compared to the photooxidation behaviour of unfilled polypropylene films with the same structural organization.

Nanocomposites Based on PCL and Halloysite Nanotubes Filled with Lysozyme: Effect of Draw Ratio on the Physical Properties and Release Analysis.

Halloysite nanotubes (HNTs) were loaded with lsozyme, as antimicrobial molecule, at a HNTs/lysozyme ratio of 1:1. Such a nano-hybrid was incorporated into a poly (-caprolactone) (PCL) matrix at 10 wt % and films were obtained. The nano-composites were submitted to a cold drawn process at three different draw ratios, = 3, 4, and 5, where is /.

Influence of carbon nanoparticles/epoxy matrix interaction on mechanical, electrical and transport properties of structural advanced materials.

The focus of this study is to design new nano-modified epoxy formulations using carbon nanofillers, such as carbon nanotubes, carbon nanofibers and graphene-based nanoparticles (CpEG), that reduce the moisture content and provide additional functional performance. The chemical structure of epoxy mixture, using a non-stoichiometric amount of hardener, exhibits unique properties in regard to the water sorption for which the equilibrium concentration of water (C ) is reduced up to a maximum of 30%. This result, which is very relevant for several industrial applications (aeronautical, shipbuilding industries, wind turbine blades, etc), is due to a strong reduction of the polar groups and/or sites responsible to bond water molecules.

Cure behavior and physical properties of epoxy resin-filled with multiwalled carbon nanotubes.

Different experimental procedures were investigated for incorporating Multi walled Carbon nanotubes (MWCNT) into epoxy diglycidil-ether bisphenol-A (DGEBA), cured with 4,4' diamine-dibenzyl-sulfone (DDS): (i) mechanical mixing for either 60 or 120 minutes; (ii) high energy ball milling for 30 minutes; (iii) ultrasonication for 20 minutes. The mechanical properties of the obtained samples were monitored and used in order to guide the selection of the most promising composite system. The best results were obtained by using, as method of incorporation of carbon nanotubes in the resin, sonication for 20 minutes.