Objective: In this work, graphene (Gr) or/and Cu particles are used to improve the thermal and mechanical properties of epoxy resin. Methods: Various contents of Gr powder (0.1, 0.3, and 0.5 wt%), and Cu powder (10, 30, and 50 wt%) were loaded to epoxy to form Gr/epoxy and Cu/epoxy composites, respectively. In addition, hybrids epoxy/Cu/Gr samples were prepared with a selection of the lowest (0.1 and 10) and the highest (0.5 and 50) ratios of Gr, and Cu, respectively. Results: The thermal conductivity increased with the increasing weight ratio of Gr and Cu as compared to the pure epoxy. The thermogravimetric analysis (TGA) of epoxy composites and hybrid composites revealed an improvement in the thermal stability. In addition, the mechanical properties such as hardness shore D and the wear resistance were enhanced for both the epoxy composites and hybrids composites. However, the Ep+0.5wt%Gr+50wt%Cu hybrid composite was found to have the maximum hardness 84, with the thermal conductivity of 3.84 W/m.K. It showed the lowest wear resistance 2.7×10^-6 mm³/Nm at loading 10 N. Conclusion: The hybrid composite containing 0.5wt%Gr and 50wt%Cu shows the maximum hardness and thermal conductivity, as well as the lowest wear resistance when compared to other composites. The physical properties of the hybrid composite can be controlled by the host blend, and hence the morphology, and interfacial characteristics.

Acrylic polymer/cement nanocomposites in dark and light colors have been developed for coating floors and swimming pools. This work aims to emphasize the effect of cement filling on the mechanical parameters, thermal stability, and wettability of acrylic polymer. The preparation was carried out using the casting method from acrylic polymer coating solution, which was added to cement nanoparticles (65 nm) with weight concentrations of (0, 1, 2, 4, and 8 wt%) to achieve high-quality specifications and good adhesion. Maximum impact strength and Hardness shore A were observed at cement ratios of 2 wt% and 4 wt%, respectively. Changing the filling ratio has a significant effect on the strain of the nanocomposites. The contact angle was increased as the concentration of additives and cement increased, indicating that the synthesized coating is not hydrophilic and does not allow water permeability through it. The results show that the acrylic polymer/cement with a cement ratio of 8 wt% is the best nanocomposite for high-efficiency waterproofing.

The acrylic polymer composites in this study are made up of various weight ratios of cement or silica nanoparticles (1, 3, 5, and 10 wt%) using the casting method. The effects of doping ratio/type on mechanical, dielectric, thermal, and hydrophobic properties were investigated. Acrylic polymer composites containing 5 wt% cement or silica nanoparticles had the lowest abrasion wear rates and the highest shore-D hardness and impact strength. The increase in the inclusion of cement or silica nanoparticles enhanced surface roughness, water contact angle (WCA), and thermal insulation. Acrylic/cement composites demonstrated higher mechanical, electrical, and thermal insulation properties than acrylic/silica composites because of their lower particle size and their low thermal/electrical conductivity. Furthermore, to improve the surface hydrophobic characteristics of acrylic composites, the surface was treated with a dielectric barrier discharge (DBD) plasma jet. The DBD plasma jet treatment significantly enhanced the hydrophobicity of acrylic polymer composites. For example, the WCA of acrylic composites containing 5 wt% silica or cement nanoparticles increased from 35.3° to 55° and 44.7° to 73°, respectively, by plasma treatment performed at an Ar flow rate of 5 L/min and for an exposure interval of 25 s. The DBD plasma jet treatment is an excellent and inexpensive technique for improving the hydrophobic properties of acrylic polymer composites. These findings offer important perspectives on the development of materials coating for technical applications.

Silver/polyvinyl alcohol (Ag/PVA) nanocomposite films were synthesized via solution casting with varying concentrations of Ag nanoparticles (1–5 wt%). A comprehensive investigation was conducted to understand the influence of Ag content on the structural, optical, mechanical, thermal, electrical, and antibacterial properties of the composites. UV-Vis spectroscopy revealed a red shift in absorption peaks and a reduction in the optical band gap, which decreased from 3.78 eV for pure PVA to 3.37 eV for the 5 wt% Ag composite. FTIR and SEM analyses confirmed successful nanoparticle incorporation and morphological changes. The nanocomposites exhibited enhanced tensile strength, elongation at break, Young’s modulus, and hardness due to strong interfacial interactions. The addition of Ag also increased hydrophobicity and imparted effective antibacterial activity. The electrical and thermal properties showed significant improvement: AC conductivity increased from 5.8 × 10⁻⁹ to 1.01 × 10⁻⁴ S/cm with Ag content, while the dielectric constant decreased. A high DC conductivity of 1.5 × 10⁵ S/cm was achieved with only 3 wt% Ag. Thermal conductivity also rose from 0.27 W/m·K for pure PVA to 0.92 W/m·K for the 5 wt% composite. These results demonstrate that Ag/PVA nanocomposites are promising multifunctional materials for flexible electronics, combining tunable optoelectronic properties with enhanced mechanical, thermal, and antibacterial performance.

In this study, epoxy–cement composites with different concentrations of cement nanofiller and ~67.5 nm in size (0, 5, 10, 15, and 20 wt%) were synthesized using the solution casting method. The epoxy–cement composites’ structural, mechanical, wettability, roughness, and thermal insulation were investigated. The synthesized epoxy resin is amorphous, whereas epoxy–cement composites are crystalline, and its crystallinity depends on the filler ratio. The incorporated cement hindered the spread of cracks and voids in the composite with few illuminated regions, and the epoxy/cement interface was identified. The Shore D hardness, impact strength, and flexural strength gradually increased to 92.3, 6.1 kJ/m², and 40.6 MPa, respectively, with an increase in the cement ratio up to 20 wt%. In contrast, the incorporation of a cement ratio of up to 20 wt% reduced thermal conductivity from 0.22 to 0.16 W/m·K. These findings indicated that resin and cement nanoparticle fillers affected the chemical composition of epoxy, which resulted in high molecular compaction and thus strong mechanical resistance and enhanced thermal insulation. The roughness and water contact angle (WCA) of epoxy increased by increasing the cement nanofiller. In contrast, the surface energy (γ) of a solid surface decreased, indicating an inverse relation compared to the behavior of roughness and WCA. The reduction in γ and the creation of a rough surface with higher WCA can produce a suitable hydrophobic surface of lower wettability on the epoxy surface. Accordingly, the developed epoxy–cement composites benefit building construction requirements, among other engineering applications.