Thermoplastic starch-based nanocomposites with varying glycerol content and montmorillonite as a nanofiller were studied using dynamic-mechanical analysis (DMA), X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) during one-year storage. DMA results showed that starch-rich and glycerol-rich domains were present in the samples and during storage for up to one year the content of the amorphous phase decreased and molecular mobility changed. C NMR and XRD measurements confirmed that ordered structures were formed during storage and its content was larger for samples with higher glycerol content and increased with the storage time.
View Article and Find Full Text PDFRecently, polyurethanes (PURs) have become a very promising group of materials with considerable utilization and innovation potential. This work presents a comprehensive analysis of the changes in material properties important for PUR applications in the electrical industry due to the incorporation of magnesium oxide (MgO) nanoparticles at different weight ratios. From the results of the investigations carried out, it is evident that the incorporation of MgO improves the volume (by up to +0.
View Article and Find Full Text PDFThermoplastic starch (TPS) consisting of corn starch and glycerol as a plasticizer, and TPS-montmorillonite (MMT) nanocomposite were stored at room temperature in the air with relative humidities (RH) of 11, 55 and 85% for seven weeks. Mechanical testing and dynamic mechanical thermal analysis (DMTA) were performed to detect changes in their mechanical properties. Solid-state NMR spectroscopy monitoring the changes in molecular mobility in the samples provided an insight into relations between mechanical properties and local structure.
View Article and Find Full Text PDFThe influence of various types of nanoparticle fillers with the same diameter of 20 nm were separately incorporated into a single component impregnating resin based on a polyesterimide (PEI) matrix and its subsequent changes in complex relative permittivity were studied. In this paper, nanoparticles of Al2O3 and ZnO were dispersed into PEI (with 0.5 and 1 wt.
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