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Black phosphorus (BP) and graphite-like carbon nitride (g-C 3 N 4) were combined to prepare BP-CN hybrid nanostructure through a simple self-assembly method assisted by ultra-sonication, and as-obtained materials were further used as fire retardants introduced into epoxy resin to fabricate EP/BP-CNx nanocomposites. It was found that the introduction of 2 wt% BP-CNx into EP contributed to considerable decrements in peak heat release rate (up to 47.72%) and total heat release (utmost to 49.60%) of composites, and LOI value increased from 25% to 31%. SSTF results revealed that the introducing of BP-CN can distinctly reduce the production of smoke. TG-IR results demonstrated that the addition of BP-CN0.5 and BP-CN2.0 into EP matrix exert different influences on the decomposition of resin. Analyses of residual chars further validated through adjusting the proportion of BP and CN can achieve different fire performances of matrix. This work illustrates that BP can reduce the fire hazards of EP, and the hybridization of CN can achieve better flame retarded efficiency, which provides a new strategy for black phosphorus to be used as a flame retardant. [ABSTRACT FROM AUTHOR]

This study introduces a new broadband hybrid perfect absorber (HA) that includes metamaterial absorber (MA) and a lossy composite. The unit cell of the MA is in the form of two concentric ring-based structures fabricated on an FR4 substrate, which provides a broadband absorption band because of two neighbouring resonance frequencies. The composite layer is built by mixing the carbon black powder and epoxy resin in an optimised weight percentage. By modelling the structure with multiple transmission line sections, a closed-form procedure has been proposed to optimise the HA parameters. The final tuning of the HA parameters is performed using HFSS. A prototype of the HA is fabricated and measured. The results indicate that the proposed HA provides nearly perfect absorption (absorption ratio over 99%) in the frequency range of 2–2.8 GHz. It is, also, polarisation-insensitive due to its symmetrical design. The total thickness of the proposed structure is 12.5 mm, which is acceptable concerning the absorption rate and the operational frequency bandwidth. [ABSTRACT FROM AUTHOR]

Microwave-absorbing samples were fabricated using carbon black powder, super-paramagnetic Zn0.8Ni0.2Fe2O4 nanoparticles dispersed in a SiO2 matrix, epoxy resin, and hardener. The paint was then coated onto a steel substrate. The effects of super-paramagnetic Zn0.8Ni0.2Fe2O4 nanoparticles content (0–1.75 wt%) and different coating thickness (1–2.5 mm) on microwave absorption ability in the X-band frequency range (8–12 GHz) have been studied. The results showed that paint sample containing only carbon black (20 wt%) and epoxy resin (80 wt%) expressed low microwave absorption ability at 10 GHz centered frequency (≈ 67% absorption percentage). The super-paramagnetic Zn0.8Ni0.2Fe2O4 nanoparticles strongly affected the microwave-absorbing ability. A sample of 1.5 wt% super-paramagnetic Zn0.8Ni0.2Fe2O4 nanoparticles content exhibited highest microwave absorption at 10 GHz centered frequency (≈ 99% power attenuation). Higher coating thicknesses (1–2.5 mm) led to greater microwave absorption and reached a very high absorption of 2 mm thickness (≈ 99% absorption percentage at 10 GHz centered frequency). [ABSTRACT FROM AUTHOR]

Pyrolysis is a viable technique to convert waste tires into recyclable products, as the dumping of these scrap tires pose a serious environmental threat. In the present investigation, a detail methodology to fabricate and characterize the carbonaceous filler (in the form of nanocarbon black obtained from pyrolysis of waste tires) modified epoxy resin composites has been retrieved. The composites with varying carbon filler content (0, 5, 10, and 15 wt%) were fabricated using the manual hand lay‐up and compression molding techniques. The morphological analysis (field‐emission scanning electron microscopy test) revealed that the synthesized pyrolytic carbon black was in nanoscale and uniformly dispersed in the epoxy matrix. Various physical (density and water absorption), mechanical (tensile, compression, flexural, hardness, and impact), electrical and thermal (differential thermal analysis and thermogravimetric analysis) tests were done to completely examine the nanocomposite developed. We found that the 5 wt% of carbon black in epoxy resin exhibited the best mechanical properties and was complemented by the microstructural (scanning electron microscopy and X‐ray diffraction) tests analysis. High tensile strength and hardness than neat epoxy resin makes this composite a potential candidate for polymer coatings in automotive industries. [ABSTRACT FROM AUTHOR]

We investigated the influence of carbon materials on the properties of adhesives. With the aim of the development of conductive and mechanically improved adhesives, different types of multi-walled carbon nanotubes (MWNT), single-layer graphene, graphene nanoplatelets, graphite, and carbon black were dispersed into an epoxy adhesive. For inserting particles within the viscous matrices and to obtain homogenous and stable dispersions, two different methods namely a three-roll mill and a dual asymmetric centrifuge have been compared The results demonstrate that filling epoxies with carbon nanoparticles improves the conductivity differently. Measuring the electrical resistivity of MWNT-filled composites resulted in an electrical percolation starting underneath 0.1 wt.%. Further, with increasing the MWNT content, conductivity sharply increases. In contrast to the MWNT composites, other carbon nanoparticles require a higher filling content to reach similar values. With a filling ratio up to 17.0 wt.% for ACS graphene nanoplatelets 2–10 nm and the filling of 3.0 wt.% with MWNTs from Nanocyl, the lowest volume resistivities have been reached. [ABSTRACT FROM PUBLISHER]

Fillers are generally used in order to change some basic properties of polymer matrix but the filler particles often tend to aggregate with consequences in terms of the mechanical properties of the final composite. In order to avoid aggregation, many solutions have been proposed and one of them is to use ultrasounds in various stages of composites formation. In this study, the compressive behaviour of filled epoxy was analysed. As filler, at a 10% volume ratio, a mixture of three parts of starch and one part carbon black was used. The aim of the analysis was to identify the effect of ultra-sonication at different frequencies and for different periods of time on the compressive properties of composites. [ABSTRACT FROM AUTHOR]

In this work we focused our attention on an innovative use of food residual biomasses. In particular, we produced biochar from coffee waste and used it as filler in epoxy resin composites with the aim to increase their electrical properties. Electrical conductivity was studied for the biochar and biochar-based composite in function of pressure applied. The results obtained were compared with carbon black and carbon black composites. We demonstrated that, even if the coffee biochar had less conductivity compared with carbon black in powder form, it created composites with better conductivity in comparison with carbon black composites. In addition, composite mechanical properties were tested and they generally improved with respect to neat epoxy resin. [ABSTRACT FROM AUTHOR]