Preparation, Characterization, and Terahertz Spectroscopy Characteristics of Reduced Graphene Oxide-Doped Epoxy Resin Coating

Reduced graphene oxide has attracted numerous interests due to its unique, superior electronic, optical, mechanical, and chemical properties. An epoxy resin with excellent mechanical and electrical properties can be obtained by doping with reduced graphene oxide to enhance the function of the polymer. Here, we prepared a uniform reduced graphene oxide/epoxy resin coating with a different reduced graphene oxide content and characterized it using a field-emission scanning electron microscope (FE-SEM), X-ray diffractometer (XRD), Raman, and Fourier transform infrared spectrometer (FTIR). Furthermore, the spectral characteristics of the composite coating in the terahertz band were discussed. The cross-sectional SEM results show that a fold structure with ductile failure was intensively formed due to the compatibility of graphene and polymer materials. Both the Raman G and Raman 2D peaks of reduced graphene oxide were confirmed using Raman spectrum testing. The diffraction peak of reduced graphene oxide at 24° disappeared within the reduced graphene oxide/epoxy resin coating, and a wide diffraction peak of the amorphous structure was formed together. Additionally, the intensity of the Raman spectrum increased significantly with increased reduced graphene oxide content, thereby making the surface electrical resistance of the coatings decrease exponentially. Additionally, the intensity of the terahertz time-domain signal and frequency-domain power spectrum linearly reduced with increased reduced graphene oxide concentration. However, the terahertz absorption coefficient and refractive index both increased gradually with increased reduced graphene oxide doping due to increased orientation polarization in the composite coating.

Anti-Corrosion Performance of Polyaniline Coated Basalt Rockwool Wastes/Epoxy Resin Coatings

Basalt rockwool wastes with large output, which are toxic and require expensive environmental treatment, are produced during the production of rock wool. Hence, it is urgent to find an effective method to reuse these materials. In this study, polyaniline (PANI)-coated basalt rockwool wastes (BRWs) were prepared as fillers to serve in coatings for the anticorrosion study. Results show that the PANI-coated BRW (PANI@BRW) had enhanced dispersion stability in several conventional solvents and improved the anticorrosion performance of the epoxy resin coating. A high protection efficiency of 97.7% could be obtained from the coating with 5% fillers after immersion for 30 days. This study not only provides a promising method of solving the issues caused by BRW, but also turns these wastes into valuable substances.

Experimental study of resin coating to improve the impact strength of fused filament fabrication process pieces

Purpose This study aims to evaluate the impact breaking energy of the parts manufactured by the fused filament fabrication (FFF) method. The evaluation considers the use of the epoxy resin coating, different materials and different printing orientations. Design/methodology/approach The authors developed an experimental statistical design using 54 experimental trials. The experiments’ output variable is the impact break energy of the parts manufactured by the FFF method. The input variables for the experiments consist of an epoxy resin coating (XTC-3D®, generic resin and without resin coating), different filament materials (nylon + carbon fiber, polyethylene terephthalate and polycarbonate) and different printing orientations (flat, edge and vertical) used. The authors carried out the tests following the EN ISO 179-1. Findings The use of resin coating has a significant influence on the impact energy of parts manufactured using the FFF method. The resin coating increases the impact resistance of parts processed by FFF by almost 100% of the value as compared to the parts without a resin coating. Post-processing is useful on ductile materials and increases impact breaking energy at weak print orientations. Originality/value This research opens a new opportunity to improve the mechanical properties of parts manufactured using the FFF method. The use of a resin coating reinforces the parts in weak print orientation.

Research on Mechanical Properties of Nano-modified Epoxy Resin Color Anti-skid pavement Materials

By referring to the domestic and foreign researches on color anti-skid pavement, the composition of epoxy resin coating material for color antiskid pavement is designed. The purpose of the experiment is to analyze the effect of nano-modified epoxy resin coating by adding 2.5% nano-organic montmorillonite modifier to the existing color anti-skid pavement surface material. Test and compare the change of mechanical properties of nano-modified epoxy resin coating binder before and after nano-modified. Then the effect of nano-modification is analyzed.