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In order to gain a fundamental understanding about the influences of filler characteristic on the electrical properties of polymer blend nanocomposites two types of graphene, graphene nanoplates (GNPs) and functionalized graphene (FG), were added to immiscible blend of poly (lactic acid)/poly(methyl methacrylate) (PLA/PMMA) and experimental and theoretical studies were carried out. Structure and properties of graphenic nanoparticles were investigated by Raman spectroscopy, elemental analysis, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD). The state of dispersion and distribution of fillers within the blend were examined by field emission scanning electron microscopy, Atomic force microscopy, transmission electron microscopy as well as XRD patterns. Theoretical modeling was carried out by several statistical and thermodynamic based models. Results showed that FG was more homogenously dispersed in the PLA matrix compared with GNP which results in lower percolation threshold and better electrical conductivity in the FG filled blends, despite its poor intrinsic electrical conductivity. For the PLA/PMMA blends filled composites, electrical conductivity modeling results showed that thermodynamic‐based models exhibit more satisfactory estimations than Power law statistical model. Thus, the electrical conductivity of two‐phase polymer blend filled with graphenic materials is predictable with thermodynamic models. POLYM. COMPOS., 40:704–715, 2019. © 2018 Society of Plastics Engineers

Herein, highly efficient, low‐cost, and lightweight solar steam generation systems are fabricated using engineered carbon and silica‐based porous nanostructures with 3D networks as light absorber and heat insulator, respectively. In this regard, systems with three different designs are considered to localize the heat efficiently through harvesting more photons and reducing heat losses. The fabricated systems are multilayered structures including polymeric foam and felt as the substrate and water‐carrier medium, respectively. Highly porous nanostructured particles of carbon aerogel (CA) as an absorber, silica aerogel (SiA) as a superinsulator, and multicore@shell aerogel of CA and SiA (CA core−SiA shell) as both absorber and insulator are synthesized. The used architectures are double layered (substrate covered by CA), triple layered (substrate covered by a layer of CA and a layer of SiA), and multicore@shell (substrate covered by CA−SiA multicore@shell aerogel). Using the double‐layered system, an efficiency of 83% corresponding to 1.2 kg m−2 h−1 water evaporation rate is achieved, which is enhanced to 90% in the triple‐layered system, where the SiA superinsulator is added. Remarkably, when the multicore@shell absorber−insulator is used, the efficiency increments of 27% and 16% are achieved compared with the double‐layered and triple‐layered ones with the same amount of absorber, respectively.