Special Packaging Materials from Recycled PET and Metallic Nano-Powders.

The European methodology for plastics, as a feature of the EU's circular economy activity plan, ought to support the decrease in plastic waste. The improvement of recycled plastics' economics and quality is one important part of this action plan. Additionally, achieving the requirement that all plastic packaging sold in the EU by 2030 be recyclable or reusable is an important objective. This means that food packaging materials should be recycled in a closed loop at the end. One of the most significant engineering polymers is polyethylene terephthalate (PET), which is widely used. Due to its numerous crucial qualities, it has a wide variety of applications, from packaging to fibers. The thermoplastic polyolefin, primarily polyethylene and polypropylene (PP), is a popular choice utilized globally in a wide range of applications. In the first phase of the current experiment, the materials were obtained by hot pressing with the press machine. The reinforcer is made of Al nanopowder 800 nm and Fe nanopowder 790 nm and the quality of the recycled polymer was examined using Fourier transform infrared spectroscopy (FTIR), a scanning electron microscope (SEM), and differential scanning calorimetry (DSC). From DSC variation curves as a function of temperature, the values from the transformation processes (glass transition, crystallization, and melting) are obtained. SEM measurements revealed that the polymer composites with Al have smooth spherical particles while the ones with Fe have bigger rough spherical particles.

Flexible Electromagnetic Shielding Nano-Composites Based on Silicon and NiFe2O4 Powders.

In this paper, the obtaining and characterization of five experimental models of novel polymer composite materials with ferrite nano-powder are presented. The composites were obtained by mechanically mixing two components and pressing the obtained mixture on a hot plate press. The ferrite powders were obtained by an innovative economic co-precipitation route. The characterization of these composites consisted of physical and thermal properties: hydrostatic density, scanning electron microscopy (SEM), and TG DSC thermal analyses, along with functional electromagnetic tests in order to demonstrate the functionality of these materials as electromagnetic shields (magnetic permeability, dielectric characteristics, and shielding effectiveness). The purpose of this work was to obtain a flexible composite material, applicable to any type of architecture for the electrical and automotive industry, necessary for protection against electromagnetic interference. The results demonstrated the efficiency of such materials at lower frequencies, but also in the microwave domain, with higher thermal stability and lifetime.

Simulation of Dielectric Properties of Nanocomposites with Non-Uniform Filler Distribution.

Dielectric properties for nanocomposites with metallic fillers inside a polymer matrix were determined using CST STUDIO SUITE-Electromagnetic field simulation software followed by the free-space Nicolson-Ross-Weir procedure. The structure is randomly generated to simulate the intrinsic non-uniformity of real nanomaterials. Cubic insertions were equated to corresponding spherical particles in order to provide either the same volume index or the same exterior surface index. The energy concentration around the inserts and within the entire material was determined as useful information in practice in order to design materials tailored to avoid exceeding the field/temperature limit values. The paper successfully associated the dialectic measurements with the results from the computer simulations, which are mainly based on energetic effects in electromagnetic applications. The experimental results are comparable with the software simulation in terms of precision. The conclusions outline the practical applications of the method for both electromagnetic shielding and microwave domain/telecommunications applications.