Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction

This work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties such as impact and flexural strength, Young’s modulus, and hardness of the material. Moreover, the dynamic mechanical analysis (DMA) showed a significant increase in the material’s storage modulus and rigidity in a wide range of temperatures. The increase in glass transition of soft segments can be noticed due to the limitation of macromolecules mobility in the material. The thermogravimetric analysis showed a four step decomposition, with maximal degradation rate at TmaxII = 320–330 °C and TmaxIII = 395–405 °C, as well as a significant improvement of thermal stability. Analysis of the material structure using a scanning electron microscope showed the presence of material defects such as voids, fiber pull-outs, and agglomerates of both fibers

Microstructure–Property Relationship of Polyurethane Foams Modified with Baltic Sea Biomass: Microcomputed Tomography vs. Scanning Electron Microscopy

In this paper, novel rigid polyurethane foams modified with Baltic Sea biomass were compared with traditional petro-based polyurethane foam as reference sample. A special attention was focused on complex studies of microstructure, which was visualized and measured in 3D with high-resolution microcomputed tomography (microCT) and, as commonly applied for this purpose, scanning electron microscopy (SEM). The impact of pore volume, area, shape and orientation on appearance density and thermal insulation properties of polyurethane foams was determined. The results presented in the paper confirm that microcomputed tomography is a useful tool for relatively quick estimation of polyurethane foams’ microstructure, what is crucial especially in the case of thermal insulation materials

Influence of Surface-Modified Montmorillonite Clays on the Properties of Elastomeric Thin Layer Nanocomposites

In recent years, polyurethane nanocomposites have attracted more attention due to the massive demand for materials with increasingly exceptional mechanical, optical, electrical, and thermal properties. As nanofillers have a high surface area, the interaction between the nanofiller and the polymer matrix is an essential issue for these materials. The main aim of this study is to validate the impact of the montmorillonite nanofiller (MMT) surface structure on the properties of polyurethane thin-film nanocomposites. Despite the interest in polyurethane–montmorillonite clay nanocomposites, only a few studies have explored the impact of montmorillonite surface modification on polyurethane’s material properties. For this reason, four types of polyurethane nanocomposites with up to 3% content of MMT were manufactured using the prepolymer method. The impact of montmorillonites on nanocomposites properties was tested by thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), contact angle measurement, X-ray diffraction (XRD), and optical coherence tomography (OCT). The results showed that chemical and physical interactions between the polymer matrix and functional groups on the montmorillonite surface have a considerable impact on the final properties of the materials. It was noticed that the addition of MMT changed the thermal decomposition process, increased T2% by at least 14 °C, changed the hydrophilicity of the materials, and increased the glass transition temperature. These findings have underlined the importance of montmorillonite surface structure and interactions between nanocomposite phases for the final properties of nanocomposites

Nanoparticles: Taking a Unique Position in Medicine

The human nature of curiosity, wonder, and ingenuity date back to the age of humankind. In parallel with our history of civilization, interest in scientific approaches to unravel mechanisms underlying natural phenomena has been developing. Recent years have witnessed unprecedented growth in research in the area of pharmaceuticals and medicine. The optimism that nanotechnology (NT) applied to medicine and drugs is taking serious steps to bring about significant advances in diagnosing, treating, and preventing disease—a shift from fantasy to reality. The growing interest in the future medical applications of NT leads to the emergence of a new field for nanomaterials (NMs) and biomedicine. In recent years, NMs have emerged as essential game players in modern medicine, with clinical applications ranging from contrast agents in imaging to carriers for drug and gene delivery into tumors. Indeed, there are instances where nanoparticles (NPs) enable analyses and therapies that cannot be performed otherwise. However, NPs also bring unique environmental and societal challenges, particularly concerning toxicity. Thus, clinical applications of NPs should be revisited, and a deep understanding of the effects of NPs from the pathophysiologic basis of a disease may bring more sophisticated diagnostic opportunities and yield more effective therapies and preventive features. Correspondingly, this review highlights the significant contributions of NPs to modern medicine and drug delivery systems. This study also attempted to glimpse the future impact of NT in medicine and pharmaceuticals