Search results for "nano-plate"
showing 5 items of 5 documents
Nonlocal model for a magneto-electro-elastic nanoplate
2013
A mathematical model based on nonlocal third-order shear deformation plate theory has been developed to evaluate the mechanical and electromagnetic behavior of magneto-electro-elastic nanoplates. Two types of magneto-electro-elastic composites have been considered, all of them combination of Barium Titanate sheets, that represents the piezoelectric phase, and Cobalt Ferrite, that is the piezomagnetic component. Setting magneto-electric boundary conditions on each laminate, it has been possible to extrapolate and to analyze free vibrations frequencies for all considered plates, allowing to do objective assessments on what factors influence laminate modes and, especially, how these vary in th…
Reprocessing of PLA/graphene nanoplatelets nanocomposites
2017
This work reports a study on the effect of multiple reprocessing on the properties of poly(lactic acid) (PLA) filled with graphene nanoplatelets (GnP) compared to the melt reprocessed neat polymeric matrix. In particular, morphological, X-Ray Diffraction and Micro-Raman analyses, intrinsic viscosity measurements, thermal, rheological and mechanical tests were carried out on materials reprocessed up five times by means of a single screw extruder. The results indicated that the presence of GnP decreased the degradation rate as a function of the reprocessing cycles in comparison with the neat PLA that, on the contrary, showed a more drastic reduction of the molecular weight. Moreover, the repr…
Photo-oxidation of polypropylene/graphene nanoplatelets composites
2019
Abstract The photo-oxidation behaviour of polymer nanocomposites depends not only on the photo-oxidation behaviour of the matrix, but also on the chemical composition, on the physical properties of the nanoparticles and on the possible interactions between the two phases. In the case of nanocomposites with carbonaceous particles, the main effect is a photo-stabilization due to the absorption of the UV energy and the radical scavenging action. In this work we investigated the effect of the presence of graphene nanoplatelets on the photo-oxidation behaviour of the polypropylene. The presence of the graphene nanoplatelets improves the photo-resistance of the polypropylene and this effect incre…
Performances and morphology of polyamide/carbonaceous structures based fibers
2014
In this work the influence of carbonaceous particles with different particle sizes and shapes on the morphology and mechanical performances of polyamide (PA) based fibers was investigated. Graphene nanoplatelets (GNP) are compared with spherical and rod-like carbon fillers such as carbon black (CB) and multiwall carbon nanotubes (MWCNT). The different morphologies of the particles control their dispersion and their alignment in PA fibers upon elongational flow action and play a key role in structure-property relationships.
Effect of graphene nanoplatelets on the dielectric permittivity and segmental motions of electrospun poly(ethylene-co-vinyl alcohol) nanofibers
2021
The influence of the addition of graphene nanoplatelets (GNPs) on the intra/inter – molecular segmental motions of poly(ethylene-co-vinyl alcohol) (EVOH) was assessed by means of dielectric thermal analysis (DETA). The relaxation spectra were studied in terms of the dielectric permittivity (ε′) and the dielectric loss tangent (tan δ) at wide ranges of frequency (from 10−2 to 107 Hz) and temperature (from -150 to 140 °C). Two relaxation zones were disthinguished. Below the glass transition temperature (Tg), two β-relaxations were observed, which are characteristic local modes of mobility of the EVOH side groups, and related to the influence of the different surroundings of ethylene or vinyl …