This review explores the impact of various additives on the mechanical properties of polylactic acid (PLA) filaments used in Fused Deposition Modeling (FDM) 3D printing. While PLA is favored for its biodegradability and ease of use, its inherent limitations in strength and heat resistance necessitate enhancements through additives. The impact of natural and synthetic fibers, inorganic particles, and nanomaterials on the mechanical properties, printability, and overall functionality of PLA composites was examined, indicating that fiber reinforcements, such as carbon and glass fibers, significantly enhance tensile strength and stiffness, while natural fibers contribute to sustainability but may compromise mechanical stability. Additionally, the inclusion of inorganic particulate fillers like calcium carbonate improves dimensional stability and printability, although larger particles can lead to agglomeration issues. The study highlights the potential for improved performance in specific applications while acknowledging the need for further investigation into optimal formulations and processing conditions.

This paper discusses the structure morphology and the thermal and swelling behavior of physically crosslinked hydrogels, obtained from applying four successive freezing–thawing cycles to poly (vinyl alcohol) blended with various amounts of κ-carrageenan. The addition of carrageenan in a weight ratio of 0.5 determines a twofold increase in the swelling degree and the early diffusion coefficients of the hydrogels when immersed in distilled water, due to a decrease in the crystallinity of the polymer matrix. The diffusion of water into the polymer matrix could be considered as a relaxation-controlled transport (anomalous diffusion). The presence of the sulfate groups determines an increased affinity of the hydrogels towards crystal violet cationic dye. A maximum physisorption capacity of up to 121.4 mg/g for this dye was attained at equilibrium.

To enhance the sliding wear and corrosion behavior of steels with low carbon content, cermet composite coatings are usually deposited on their surface by various deposition processes. Laser cladding, compared to other deposition techniques such as electroplating, arc welding, and thermal spraying, has numerous advantages to produce such protective coatings. The paper presents the optimization of laser cladding deposition speed versus energy density in order to obtain WC-Co/NiCrBSi coatings with Ni-Al addition free of defects and reduced porosity deposited on low carbon steel substrate. The microstructure and chemical composition were investigated by SEM combined with EDX analysis while XRD was performed in order to examinate the phases within the coatings. In order to investigate the cladding speed influence on the coatings, hardness measurements, POD (pin on disk) wear tests and corrosion tests in 3.5% NaCl solution were carried out. The results showed that an optimal cladding speed has a crucial impact on the microstructure, composition, and hardness. It was found out that optimizing the cladding deposition speed proved to be effective in enhancing the sliding wear resistance and corrosion behavior by controlling the iron content within the coatings.

This paper reports the obtaining of poly (vinyl alcohol) and ι-carrageenan blend hydrogels by physical crosslinking (consecutive freeze–thaw cycles). The two polymers were completely miscible in the weight ratio interval used in this study, as determined by solution viscometry data. Strong interactions through hydrogen bonding and forming of mixed interpolymer crystalline domains were observed, which are responsible for the formation of stable drug release-tunable matrices. The release profiles of three model antibiotic drugs (amoxicillin, tetracycline hydrochloride, and gentamicin sulfate) were assessed in a pH interval between 3 and 7.3. They were found to be strongly dependent on the drug chemistry, mesh size of the hydrogels, swelling mechanism, and pH of the release medium. A decrease of up to 40% in the release rates and up to 10% in the diffusion coefficients of the model drugs was registered with the increase in ι-carrageenan content.

Due to its wide applicability in industry, devising microstructures on the surface of materials can be easily implemented and automated in technological processes. Laser Surface Texturing (LST) is applied to modify the chemical composition, morphology, and roughness of surfaces (wettability), cleaning (remove contaminants), reducing internal stresses of metals (hardening, tempering), surface energy (polymers, metals), increasing the adhesion (hybrid joining, bioengineering) and decreasing the growth of pathogenic bacteria (bioengineering). This paper is a continuation and extension of our previous studies in laser-assisted texturing of surfaces. Three different patterns (crater array-type C, two ellipses at 90° overlapping with its mirror-type B and 3 concentric octagons-type A) were applied with a nanosecond pulsed laser (active medium Nd: Fiber Diode-pumped) on the surface of a ferritic stainless steel (AISI 430). Micro texturing the surface of a material can modify its wettability behavior. A hydrophobic surface (contact angle greater than 90°) was obtained with different variations depending on the parameters. The analysis performed in this research (surface roughness, wettability) is critical for assessing the surface functionality, characteristics and properties of the stainless steel surface after the LST process. The values of the surface roughness and the contact angle are directly proportional to the number of repetitions and inversely proportional to the speed. Recommendations for the use of different texturing pattern designs are also made.

Ionic liquids represent a class of highly versatile organic compounds used extensively in the last decade for lignocellulose biomass fractionation and dissolution, as well as property modifiers for wood materials. This review is dedicated to the use of ionic liquids as antifungal agents for wood preservation. Wood preservation against fungal attack represents a relatively new domain of application for ionic liquids, emerging in the late 1990s. Comparing to other application domains of ionic liquids, this particular one has been relatively little researched. Ionic liquids may be promising as wood preservatives due to their ability to swell wood, which translates into better penetration ability and fixation into the bulk of the wood material than other conventional antifungal agents, avoiding leaching over time. The antifungal character of ionic liquids depends on the nature of their alkyl-substituted cation, on the size and position of their substituents, and of their anion. It pertains to a large variety of wood-colonizing fungi, both Basidiomycetes and Fungiimperfecti.