The materials used as filaments for additive techniques should exhibit various properties depending on the application and the requirements. The motivation for this study was the need to obtain a filament exhibiting appropriate aesthetic (metal-like) and mechanical properties. Glycol-modified poly(ethylene terephthalate) copolymer (PETG) and micrometric steel powder were used for composite preparation. Subsequently, the obtained material was used as a filament for 3D printing, i.e., by fused deposition modeling (FDM) technique. The physicochemical properties of the obtained filaments were determined, such as morphology (roughness), moisture sorption ability, thermal properties, and mechanical performance (tensile and compressive strength). Importantly, the metal filler did not modify the thermal properties of the polyester matrix, indicating that the filament containing steel microfiller could be processed using the same parameters as for neat PETG. The thermal stability was slightly enhanced after steel powder addition (for 13 wt.% content, the temperature of 75% weight loss was 466 °C; for comparison, that for the reference sample was 446 °C). The reinforcing effect of steel microfiller was noted based on mechanical performance measurements. The steel particles acted as a stiffening agent; the highest maximal tensile strength was observed for the composite with 3 wt.% steel powder content (ca. 68 MPa). Further increasing the microfiller load resulted in a slight decrease in the value of this parameter. A different trend was reported considering the compressive strength, i.e., the value of this parameter increased with steel content. Based on the obtained results, the new PETG composites could be applied as structural materials.

Selected transparent polymers [i.e., polystyrene (PS) and poly(methyl methacrylate) (PMMA)] were extruded with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The obtained compositions were formed into testing samples by injection molding process. The obtained materials (containing 1–10 wt parts/100 wt parts of the polymer) exhibited higher melt flow rate and thermal resistance, as well as reduced flammability (while maintaining their mechanical properties). Additionally, Fourier transform infrared spectroscopy (FT-IR) analysis of modified polymers was conducted. Studies confirmed that – during the extrusion and/or injection molding – DOPO reacts with PS and PMMA.

The presence of flammable substances nearby hot surfaces in the engine rooms pose a fire hazard. Therefore the quick and effective removal of oil spills from these areas is of utmost importance. The simplest way is to use sorbent materials having the capacity to absorb oil substances. Oil sorbents comprise of a wide range of organic, inorganic and synthetic products. The choice of form and type of sorbent material depends on the intended application: type of spill, its size and location. The article describes the results of studies aimed to compare the absorbency of selected natural and synthetic sorbents in the context of their application in case of an oil spill in the engine room. Although the natural sorbents should not be used in water, because they absorb it and can in addition contaminate the seabed, they can be used to remove oil spills on the ship. After used they can be disposed on the ship by burning.