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In this work, epoxy (EP) resin composites with "point‐surface" heterostructures constructed by hybrid fillers of Ni particles and graphene nanosheets (GNPs) are prepared via a blending method under magnetic field. Effects of filler content and magnetic orientation on dielectric, thermally and electrically conductive, and thermomechanical properties of the resultant composites are investigated. The findings disclose that the synergistic effect of hybrid fillers and the magnetic orientation result in the formation of a complex heterogeneous network structure, significantly improving both thermal and electrical conductivities. From the temperature distribution analysis, it is the construction of the heterogeneous network that improves the thermally conductive and thermomechanical properties. Sample Y4 (containing 28 wt% Ni and 2 wt% GNP) displays an average heating rate (AHR) of 152.4 °C min−1 and has an out‐of‐plane thermal conductivity of 0.930 W m−1 K−1 (267.6% higher than that of neat EP). The infrared thermal imaging (ITI) together with SEM observations further confirms that the Ni chains in situ formed under a magnetic field are responsible for the improved composite's thermal conductivity and thermal management capability, which make it potentially applicable for 3D packaging materials in power‐intensive electronic components. [ABSTRACT FROM AUTHOR]

In this work, polymethyl methacrylate (PMMA) composites modified with diethylaluminum phosphonate (ADP) and epoxy resin (EP) as flame retardant and toughener, respectively, were prepared via solution method for improvement on both flame retardancy and toughening purposes. The effects of ADP and EP loadings on the viscoelastic, flame retardant and thermomechanical behaviors of the resultant composites were intensively investigated using rheometer, CONE calorimetry, oxygen index (LOI) and dynamic mechanical thermal analysis (DMTA), respectively. Heat flux complexity was obviously displayed when ADP and EP loadings increased. DMTA result showed that the increase of the modulus of the composites was primarily due to an interpenetrating polymer network (IPN) formed by the addition of EP, and the tensile properties were found to be greatly improved. In addition, our study also showed that at an ADP loading of 28% the maximum heat release rate (pHRR) of composites decreased by 63% as compared to neat PMMA with increase by 88% in LOI and V‐0 grade in UL‐94 test achieved. The composites prepared in this study bore excellent fire performance together with desired toughness, and the current work thus has practical significance for further expanding the application range of PMMA composites. [ABSTRACT FROM AUTHOR]

Solar vapor generation is a sustainable and cost‐effective approach to addressing the issue of water shortage. However, the challenges of solar steam generation still exist for achieving a high evaporation efficiency combined with long‐term stability in the wastewater containing heavy metal ions and wide degrees of acidity and alkalinity (pH = 1–14). Herein, polypyrrole (PPy) loading on the N,S‐doped graphene oxide (N,S‐GO) foam is used for high‐efficiency solar evaporation of treating wastewater. With the advantages of excellent broadband solar absorption (>97%), extremely low emissivity (0.70), and outstanding hydrophilicity, the N,S‐GO/PPy foam achieves a high evaporation efficiency of 90.5% under 1 sun illumination. More notably, the N,S‐GO/PPy foam has strong adsorption of heavy metal ions (Fe3+, Cu2+, and Cr6+) for treating wastewater synchronously evaporates at higher efficiencies of 94.7–98.4%. Interestingly, the high‐toxicity Cr6+ can be reduced to low‐toxicity Cr3+ effectively by the synergistic effect of N,S‐GO and PPy. In addition, the N,S‐GO foam shows a better long‐term resistance of acidity and alkalinity for 45 days. A new insight is offered into high‐efficiency solar evaporation for treating wastewater and water purification. [ABSTRACT FROM AUTHOR]

Micron iron was added into poly(vinylidene fluoride) (PVDF) via solution method to prepare the PVDF conductive composites. The electrical properties, non‐isothermal crystallization kinetics, crystal form, rheological, and thermal properties of PVDF/Fe composites were studied. Compared with neat PVDF, the PVDF/Fe composites had a higher crystallization rate, thermal stability and conductivity, but both crystallinity and flow property would decrease. The PVDF/Fe composites were subsequently treated by an alternating magnetic field. The percolation threshold value of the composites was found to reduce from 30 vol % to 11 vol %. The conductivity of the PVDF/Fe composites after alternating magnetic treatment increased by 8 orders of magnitude in comparison to neat PVDF, and the electrical conductivity of the PVDF/Fe composite with 30 vol % iron content was about 10−0.58 S m−1. The iron particles were more likely to form a conductive network in the polymer matrix after the magnetic field treatment according to morphological observation. The present work will supply an insight into the design of PVDF conductive composites as well as the further studies on the relationship between structure and property of polymer composites. POLYM. COMPOS., 40:E88–E101, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, the melt strength of PP matrix was reinforced by crosslinking-modified PP (CM-PP) which was yielded by peroxide-initiated crosslinking of linear PP with butyl acrylate (BA). The nano-silica aerogel (nano-SiO2) worked as a nucleating agent for foaming. The effects of CM-PP with the various contents of BA on the foaming behavior and thermal property of PP were studied by measurements of density, thermal conductivity, Vicat softening temperature and SEM. The results showed that the foamed PP got the best properties when the crosslinking PP modified with the weight ratio of butyl acrylate was 10 wt %. The density of the obtained foamed PP with uniform closed cells was as low as 0.23 g/cm3, the thermal conductivity was 0.044 W/(m K), and the Vicat softening temperature was 120 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44340. [ABSTRACT FROM AUTHOR]