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There is a strong need to develop and implement appropriate alternatives to replace formaldehyde-based adhesive systems, such as phenol–formaldehyde, in the industry of wood-based panels (WBPs). This is due to the toxicity and volatility of formaldehyde and restrictions on its use associated with some formaldehyde-based adhesives. Additionally, the current pressure to reduce the dependence on polymeric materials, including adhesives, from petrochemical-based sources has led to increased interest in bio-based adhesives, which, in some cases, already provide acceptable properties to the end-product. Among the potential raw materials for good-quality, renewable-based adhesive formulations, this paper highlights tannins, lignin, and protein sources. However, regarding renewable sources, specific features must be considered, such as their lower reactivity than certain petrochemical-based sources and, therefore, higher production costs, resource availability issues, and the need for toxicological investigations on alternative systems, to compare them to conventional systems. As a result, further research is highly encouraged to develop viable formaldehyde-free adhesive systems based on renewable sources, either at the technical or economical level. Moreover, herein, we also showcase the present market of WBPs, highlighting the obstacles that the alternative and new bio-based adhesives must overcome.

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Biomass can be envisaged as a potential solution to mitigate the problems that the extensive exploitation of fossil sources causes on the environment. Transforming biomass into added-value products with better calorific properties is highly desired. Thermochemical liquefaction can convert biomass into a bio-oil. The work herein presented concerns the study of direct liquefaction of Eucalyptus globulus sawdust. The main goal was to optimise the operating conditions of the process to achieve high bio-oil conversion rates. Studies were carried out to understand the impact of the process factors, such as the residence time, catalyst concentration, temperature, and the biomass-to-solvent ratio. The E. globulus sawdust conversion into bio-oil was achieved with a maximum conversion of 96.2%. A higher conversion was reached when the eucalyptus sawdust's thermochemical liquefaction was conducted over 180 minutes in the presence of a >2.44% catalyst concentration at 160 °C. A lower biomass-to-solvent ratio favours the process leading to a higher conversion of biomass into bio-oil. The afforded bio-oil presented a better higher heating value than that of E. globulus sawdust.

Onychomycosis affects about 15% of the population. This disease causes physical and psychosocial discomfort to infected patients. Topical treatment (creams, solutions, gels, colloidal carriers, and nail lacquers) is usually the most commonly required due to the high toxicity of oral drugs. Currently, the most common topical formulations (creams and lotions) present a low drug delivery to the nail infection. Nail lacquers appear to increase drug delivery and simultaneously improve the effectiveness of treatment with increased patient compliance. These formulations leave a polymer film on the nail plate after solvent evaporation. The duration of the film residence in the nail constitutes an important property of nail lacquer formulation. In this study, a polyurethane polymer was used to delivery antifungals drugs, such as terbinafine hydrochloride (TH) and ciclopirox olamine (CPX) and the influence of its concentration on the properties of nail lacquer formulations was assessed. The nail lacquer containing the lowest polymer concentration (10%) was the most effective regarding the in vitro release, permeation, and antifungal activity. It has also been demonstrated that the application of PU-based nail lacquer improves the nail plate, making it smooth and uniform and reduces the porosity contributing to the greater effectiveness of these vehicles. To conclude, the use of polyurethane in nail formulations is promising for nail therapeutics.