Hydroxymethylfurfural (HMF) is a high‐value platform chemical derived from renewable resources. In recent years, considerable efforts have been made to produce HMF also at industrial scale, which still faces some challenges regarding yield as well as sustainable and economic process designs. This critical Review evaluates the industrial process development of sustainable biomass conversion to HMF. Qualitative and quantitative guidelines are defined for the technological assessment of the processes described in patent literature. The formation of side products, difficulties in the separation and purification of HMF as well as catalyst regeneration were identified as major challenges in the HMF production. A first small‐scale, commercial HMF production plant with a capacity of 300 t_HMF per year has been operating in Switzerland since 2014.

Cellulose derivatives have many potential applications in the field of biomaterials and composites, in addition to several ways of modification leading to them. Silanization in aqueous media is one of the most promising routes to create multipurpose and organic–inorganic hybrid materials. Silanization has been widely used for cellulosic and nano-structured celluloses, but was a problem so far if to be applied to the common cellulose derivative “dialdehyde cellulose” (DAC), i.e., highly periodate-oxidized celluloses. In this work, a straightforward silanization protocol for dialdehyde cellulose is proposed, which can be readily modified with (3-aminopropyl)triethoxysilane. After thermal treatment and freeze-drying, the resulting product showed condensation and cross-linking, which was studied with infrared spectroscopy and ¹³C and ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy. The cross-linking involves both links of the hydroxyl group of the oxidized cellulose with the silanol groups (Si-O-C) and imine-type bonds between the amino group and keto functions of the DAC (-HC=N-). The modification was achieved in aqueous medium under mild reaction conditions. Different treatments cause different levels of hydrolysis of the organosilane compound, which resulted in diverse condensed silica networks in the modified dialdehyde cellulose structure.

5‐Hydroxymethylfurfural (HMF) is a promising bio‐derived platform chemical with a broad scope of application, for example, in the production of solvents, fuels, polymers, or adhesives. The wood and foundry industries are among the largest adhesive users and currently both rely to a large extent on the use of fossil‐based binders, such as by using formaldehyde as a crosslinker in many commercial adhesive systems. The industry is thus looking for suitable alternatives to replace fossil‐based chemicals. HMF and its derivatives are considered to be key renewable reactants in adhesive systems. The core of this Review is the critical evaluation of the potential of HMF and its derivatives in adhesive systems. The technological performance was assessed in the fields of wood‐based materials, sand casting and composites. As an overall conclusion, HMF and its derivatives have a high application potential in alternative adhesives. Clearly, further research is needed to improve the performance and produce economically competitive adhesives.

A highly active, genuinely heterogeneous catalyst for liquid-phase Diels–Alder reactions of enones results from the silanol centred modification of an incompletely condensed silasesquioxane with trimethylaluminium, the resulting catalytic material being a gel that contains aluminium(III) siloxy functions (Al–O–Si) which are incorporated in a well defined, three-dimensional SiO framework.

The purpose of this experimental research study was to obtain new understanding on adhesion and mechanical characteristics of impregnated spruce veneer samples wherein a low molecular weight phenol formaldehyde (PF) resin simultaneously acts both as impregnant and as adhesive. Impregnated veneer specimens were pre-dried by varying drying temperature and duration in order to obtain samples with different intermediate states of condensation. After bond formation, tensile shear strength and corresponding wood failure amount were determined. In the second part of this study, press parameters (i.e., pressing temperature and pressing time) were varied to obtain knowledge about the curing behaviour of pre-dried PF-impregnated veneer specimens. Tensile shear strength of the adhesive bond, tensile strength, the corresponding modulus of elasticity and hardness of the substrate material were determined in addition. As a result, clear effects of the various investigated parameters could be observed. While drying temperatures mainly affected the tensile shear strength, excessive pressing temperatures and times showed an impact on both, the tensile shear strength and (negatively) on the mechanical properties of the wood substrate.