The first report of using limonene derivative of a spherosilicate as a modifier of polylactide used for 3D printing and injection moulding is presented. The paper presents the use of limonene-functionalized spherosilicate derivative as a functional additive. The study compared the material characteristics of polylactide modified with SS-Limonene (0.25–5.0% w/w) processed with traditional injection moulding and 3D printing (FFF, FDM). A significant improvement in the processing properties concerning rheology, inter-layer adhesion, and mechanical properties was achieved, which translated into the quality of the print and reduction of waste production. Moreover, the paper describes the elementary stages of thermal transformations of the obtained hybrid systems.

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Due to the current trends in sustainable development and the reduction in the use of fossil fuels (Green Deal strategy and the circular economy), and thus, the increased interest of the polyurethane industry in polyols derived from renewable sources, it is important to study the impact of these polyols on the flammability of new bioelastomers. The goal of this study was to check the influence of biobased polyols, such as tall oil (TO)-based polyols, soybean oil (SO)-based polyol, and rapeseed oil (RO)-based polyol, on the reduction in the burning and fume emissions of polyurethane and poly(urea)urethane elastomers (EPURs and EPUURs). The thermal stability of these materials was tested using thermogravimetric analysis (TGA). In turn, the flame retardancy and smoke emissions were checked using a cone calorimetry test. The released gases were identified using TGA coupled with Fourier transform infrared (FT-IR) spectroscopy (TGA/FT-IR). Moreover, the morphological and structural characteristics of the char residues were characterized using FT-IR and scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). The obtained data were compared to the results received for elastomers produced with petroleum substrates. The addition of biobased polyols led to a reduction in the burning as a result of the formation of char, especially RO polyol. Moreover, the TO and RO polyols increased the thermal stability of the elastomers.

The work presents a comprehensive profile of the physicochemical characteristics of opoka sedimentary rock in the context of its use as a hybrid filler for thermoplastics. Determining the functional parameters of the studied filler was the main aim of this research. Thermal treatment leads to changes in its morphology and phase composition. A wide range of physicochemical techniques was used, such as low-temperature nitrogen adsorption, FT-IR, TGA, XRD, optical, and electron microscopy. The susceptibility of the material to micronisation was also tested (ball milling). Due to its widespread occurrence, opoka can be an attractive alternative to fillers such as silica or chalk. In order to verify this statement, polypropylene composites thereof were prepared by melt blending and injection molding, and studied by mechanical testing and microscopic imaging.

Polyamide 11/multi-walled carbon nanotubes nanocomposite fibers with weight fraction 2, 4, and 6 wt.% and diameter 80 lm were prepared with a twin screw mini-extruder. The morphology and degree of dispersion of the multi-walled carbon nanotubes in the fibers was investigated by using scanning and transmission electron microscopy. In turn, the molecular structure was indicated by using wide-angle x-ray scattering and correlated with thermal analysis. It was found that carbon nanotubes lead to the formation of a phase in the fibers and they show medial level of alignment within the length of the fiber. Mechanical analysis of the fibers shows that apart from the crystallinity content, the tensile strength is strongly dependent on the macroscopic defects of the surface of the fibers. Nanocomposite fibers based on polyamide 11 with carbon nanotubes can be used as a precursor for non-woven or woven fabrics manufacturing process.

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Ice accumulation is a key and unsolved problem for many composite structures with polymer matrices, e.g., wind turbines and airplanes. One of the solutions to avoid icing is to use anti-icing coatings. In recent years, the influence of hydrophobicity of a surface on its icephobic properties has been studied. This solution is based on the idea that a material with poor wettability maximally reduces the contact time between a cooled drop of water and the surface, consequently prevents the formation of ice, and decreases its adhesion to the surface. In this work, a hybrid modification of a gelcoat based on unsaturated polyester resin with nanosilica and chemical modifiers from the group of triple functionalized polyhedral oligomeric silsesquioxanes (POSS) and double organofunctionalized polysiloxanes (generally called multi-functionalized organosilicon compounds (MFSC)) was applied. The work describes how the change of modifier concentration and its structural structure finally influences the ice phobic properties. The modifiers used in their structure groups lowered the free surface energy and crosslinking groups with the applied resin, lowering the phenomena of migration and removing the modifier from the surface layer of gelcoat. The main studies from the icephobicity point of view were the measurements of ice adhesion forces between modified materials and ice. The tests were based on the measurements of the shear strength between the ice layer and the modified surface and were conducted using a tensile machine. Hydrophobic properties of the obtained nanocomposites were determined by measurement of the contact angle and contact angle hysteresis. As the results of the work, it was found that the modification of gelcoat with nanosilica and multi-functionalized silicone compounds results in the improvement of icephobic properties when compared to unmodified gelcoat while no direct influence of wettability properties was found. Ice adhesion decreased by more than 30%.