Studies on the Effect of the Addition of Nano-Spherical Particles of Aluminum on the Thermal, Mechanical, and Morphological Properties of PBT-PET Blend Composites

Thermomechanical and Structural Analysis of Manufactured Composite Based on Polyamide and Aluminum Recycled Material

The paper presents an analysis of the filler's effect on the machining process and on changes in the thermomechanical properties of polymer composites based on aluminum chips. Composite research samples with a polymer matrix in the form of polyamide 6 were made by the pressing method. Comparative studies were carried out on the changes in thermomechanical properties and structure of the obtained molders with different filler contents and different fractions after the machining process. In order to determine the changes in thermal and mechanical properties, analysis was carried out using the differential scanning calorimetry (DSC) method, thermal analysis of dynamic mechanical properties (DMTA) and a detailed stereometric analysis of the surface. After mechanical processing, roughness amplitude parameters and volumetric functional parameters were determined. In order to analyze the structure, tomographic examinations of the manufactured composite were conducted. In relation to the polymer matrix, a significant increase in the storage modulus of the composites was noted in the entire temperature range of the study. An increase in the enthalpy of melting of the matrix was noted in composites with a lower filler content and a shift in the melting range of the crystalline phase. Significant differences were noted in the study of the composite surfaces in the case of using fillers obtained after machining with different fractions. The dependencies of the functional and amplitude parameters of the surfaces after machining of composite samples prove the change in the functional properties of the surface. The use of aluminum chips in the composite significantly changed the surface geometry.

Mouldable Conductive Plastic with Optimised Mechanical Properties

This paper investigates making an injection mouldable conductive plastic formulation that aims for conductivity into the electromagnetic interference (EMI) shielding range, with good mechanical properties (i.e., stiffness, strength, and impact resistance). While conductivity in the range (electrostatic charge dissipation) and EMI shielding have been attained by incorporating conductive fillers such as carbon black, metals powders, and new materials, such as carbon nanotubes (CNTs), this often occurs with a drop in tensile strength, elongation-to-break resistance, and impact resistance. It is most often the case that the incorporation of high modulus fillers leads to an increase in modulus but a drop in strength and impact resistance. In this work, we have used short carbon fibres as the conductive filler and selected a 50/50 PBT/rPET (recycled PET) for the plastic matrix. Carbon fibres are cheaper than CNTs and graphenes. The PBT/rPET has low melt viscosity and crystallises sufficiently fast during injection moulding. To improve impact resistance, a styrene-ethylene-butadiene-styrene (SEBS) rubber toughening agent was added to the plastic. The PBT/rPET had very low-impact resistance and the SEBS provided rubber toughening to it; however, the rubber caused a drop in the tensile modulus and strength. The short carbon fibre restored the modulus and strength, which reached higher value than the PBT/rPET while providing the conductivity. Scanning electron microscope pictures showed quite good bonding of the current filler (CF) to the PBT/rPET. An injection mouldable conductive plastic with high conductivity and raised modulus, strength, and impact resistance could be made.

Developing of Lead/Polyurethane Micro/Nano Composite for Nuclear Shielding Novel Supplies: γ-Spectroscopy and FLUKA Simulation Techniques

In this work, the effect of adding Pb nano/microparticles in polyurethane foams to improve thermo-physical and mechanical properties were investigated. Moreover, an attempt has been made to modify the micron-sized lead metal powder into nanostructured Pb powder using a high-energy ball mill. Two types of fillers were used, the first is Pb in micro scale and the second is Pb in nano scale. A lead/polyurethane nanocomposite is made using the in-situ polymerization process. The different characterization techniques describe the state of the dispersion of fillers in foam. The effects of these additions in the foam were evaluated, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) have all been used to analyze the morphology and dispersion of lead in polyurethane. The findings demonstrate that lead is uniformly distributed throughout the polyurethane matrix. The compression test demonstrates that the inclusion of lead weakens the compression strength of the nanocomposites in comparison to that of pure polyurethane. The TGA study shows that the enhanced thermal stability is a result of the inclusion of fillers, especially nanofillers. The shielding efficiency has been studied, MAC, LAC, HVL, MFP and Zeff were determined either experimentally or by Monte Carlo calculations. The nuclear radiation shielding properties were simulated by the FLUKA code for the photon energy range of 0.0001-100 MeV.