Materials science is an interdisciplinary area of studies. This science focuses on the influence of the physico-chemical properties of materials on their application in human everyday lives. The materials’ synthesis should be developed in accordance with sustainable development. Polyurethanes (PUR) represent a significant consumption of plastic in the world. Modification of PUR, e.g., with polysaccharide of natural origin (chitosan, Chit), should have a positive effect on their functional properties and degradability in the natural environment. The basic parameters affecting the scope and direction of changes are the size and quantity of the chitosan particles. The impact assessment of chitosan on the chemical structure, morphology, thermal properties, crystallinity, mechanical properties, flammability, water sorption, adsorption properties, degradability, and biological activity of PUR/Chit composites (without other additives) is discussed in this article. To the best of our knowledge, recent literature does not contain a study discussing the direct impact of the presence of chitosan in the structure of PUR/Chit composite on its properties, regardless of the intended uses. This paper provides an overview of publications, which presents the results of a study on the effect of adding chitosan in polyurethane/chitosan composites without other additives on the properties of polyurethane.

Polyurethanes are most often called “green” when they contain natural, renewable additives in their network or chemical structure, such as mono- and polysaccharides, oils (mainly vegetable oils), polyphenols (e.g., lignins, tannins), or various compounds derived from agro-waste white biotechnology (Principle 7). This usually results in these polyurethanes obtained from less hazardous substrates (Principle 4). Appropriate modification of polyurethanes makes them susceptible to degradation, and the use of appropriate processes allows for their recycling (Principle 10). However, this fulfilment of other principles also predisposes them to be green. As in the production of other polymer materials, the synthesis of polyurethanes is carried out with the use of catalysts (such as biocatalysts) (Principle 9) with full control of the course of the reaction (Principle 11), which allows maximization of the atomic economy (Principle 2) and an increase in energy efficiency (Principle 6) while minimizing the risk of production waste (Principle 1). Moreover, traditional substrates in the synthesis of polyurethanes can be replaced with less toxic ones (e.g., in non-isocyanate polyurethanes), which, at the same time, leads to a non-toxic product (Principle 3, Principle 5). In general, there is no need for blocking compounds to provide intermediates in the synthesis of polyurethanes (Principle 8). Reasonable storage of substrates, their transport, and the synthesis of polyurethanes guarantee the safety and the prevention of uncontrolled reactions (Principle 12). This publication is a summary of the achievements of scientists and technologists who are constantly working to create ideal polyurethanes that do not pollute the environment, and their synthesis and use are consistent with the principles of sustainable economy.

The antioxidant properties of oxydiacetate complexes of cobalt(II) and nickel(II) with 1,10-phenantroline and 2,2'-bipyridine have been investigated towards the superoxide radical using the nitro blue tetrazolium chloride (NBT) test and the cyclic voltammetry (CV). Moreover, the biological activity of the complexes under study has been investigated in the Human Dermal Fibroblasts adult (HDFa) cell line. In the first step, the cytotoxic and the antiproliferative activities of the complexes were examined. Subsequently, the cytoprotective properties of the complexes have been investigated in an oxidative stress conditions induced by HO.

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Shrimp waste is a common waste in seafood processing. It is used as part of the fish meal which is added to feed. Bearing in mind the Green Deal and sustainability development, it was proposed to use northern prawn shells to obtain chitosan (Ch), which could then be used for polyurethane (PUR) modification. In ports, oil micro-spills often flow into the waters of gulfs and, consequently, into the sea. Systematic chemical and petroleum water pollution may pose a threat to flora and fauna. In this study, chitosan, which was obtained from shrimp shells, was used to synthesize polyurethane–chitosan foams (PUR+Ch) with different chitosan concentrations. Selected physico-chemical and sorption properties in relation to oil and water of these materials were determined. It was found that the amount of Ch added to the foam affected its morphology, hardness, density, and thermal and sorption properties. PUR foam with a 1.5% weight of Ch was characterized as having the highest water and oil sorption. The advantages of the tested material as an innovative product with potentially significant proecological values were estimated using strengths–weaknesses–opportunities–threats (SWOT) analysis. The conducted preliminary research made it possible to demonstrate the use of these materials in the processes of water treatment with the mentioned micropollutants.

Polysaccharides are polymers of long chains of monosaccharide units linked via glycosidic bonds. Starch, cellulose, chitin and their derivatives, such as chitosan, are examples of polysaccharides. Chitin is the second most common natural polysaccharide in the world (after cellulose). Chitin and chitosan are amino polysaccharides. Chitosan is often obtained by chemical, or sometimes enzymatic, deacetylation of chitin. These compounds are increasingly being modified to the nanometric scale. New engineering nanomaterials show better chemical, biological, mechanical, thermal, electrical and sorption properties than the primary materials. In this paper, the methods of chitosan nanomaterials synthesis and their adsorption properties of metal cations are discussed. As it is shown, the selected chitosan nanomaterials have promising adsorption properties of metal cations.

The kinetics of the aquation reaction of the [VO(ida)(bipy)]·2H2O (VO(ida)(bipy)) complex (where ida = iminodiacetate anion and bipy = 2,2’-bipyridine) promoted by [Fe(H2O)6]3+ ions were investigated in aqueous solutions. Spectrophotometric studies were carried out at different temperatures in the range of 293.15–313.15 K. The concentration of the [Fe(H2O)6]3+ (Fe3+) ions was kept within the range of 2 × 10–4 to 8 × 10–4 mol L–1, and the concentration of VO(ida)(bipy) was 1 × 10–3 mol L–1. The values of the observable reaction rate constants were calculated based on the Glint computer program. Furthermore, the mechanism for the aquation of VO(ida)(bipy), induced by Fe(III) ions, has been proposed.