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Growing demand for animal products caused by a growing population and improved living-standards also yields large quantities of manure constituting an eminent problem. Herbivore manure can be utilized as fertilizer or for biogas production, which, however, disregards the full potential of manure as feedstock for lignocellulosics. Thus, an integrated process combining biogas production and isolation of natural fibres next to providing fertilizer precursors would constitute a major leap forward.

Multifunctional, biobased materials processed by the means of additive manufacturing technology can be highly applicable within the water treatment industry. This work summarizes a scalable and sustainable method of anchoring...

Funding Information: The authors acknowledge Tiergarten Schönbrunn for providing the elephant manure, Johannes Theiner from the Microanalytical Laboratory (Faculty of Chemistry) at the University of Vienna for performing elemental analysis and IR-spectroscopy, and the following students for their help with various aspects of the work: Alexander Blocher, Lisa Panzenböck, Hanna Hirn, Nina Troppmaier, Manuel Holzman (all University of Vienna), and Elodie Schaffner (Institut National Polytechnique de Toulouse). The authors also thank Stephan Puchegger from the Faculty Center for Nano Structure Research for his help with the SEM and Antje Potthast (Institute of Chemistry of Renewable Resources, University of Natural Resources and Life Sciences, Vienna) for measuring the molecular weight of the cellulose. This work was supported by OeAD (WTZ ZA 03/2017) enabling the collaboration with CSIR, Port Elisabeth, South Africa. K.W. is grateful for the financial support provided by the Institute of Materials Chemistry of University of Vienna (371300). E.K. acknowledges the support by FinnCERES Materials Bioeconomy Ecosystem. Publisher Copyright: © 2021 The Authors. Published by American Chemical Society. The demand for animal products has significantly increased over the past decades as a result of the growing population and the heightened standards of living. Increased livestock farming does not only yield desired products but also significant quantities of wastes, particularly manure whose storage and application are being monitored with a tightening network of regulations. The problem is that manure is considered merely as a substrate for biogas production or as a fertilizer, whereas the substantial portion of fibers residing in herbivore manure has remained underutilized. Here, we propose a manure management system, in which not only biogas and fertilizer precursors but also high-value materials in the form of (nano)cellulose are produced. We show that high biogas yields can be achieved for elephant manure and the remaining substrate enables effortless isolation of cellulose nanofibers, leading to a significant reduction of the environmental impact compared with traditional systems based on wood.

We report on the synthesis and characterization of three new nanosized main group V heteropolyoxotungstates KxNay[H2(XWVI9O33)(WVI5O12)(X2WVI29O103)]·nH2O {X3W43} (x = 11, y = 16, and n = 115.5 for X = SbIII; x = 20, y = 7, and n = 68 for X = BiIII) and K8Na15[H16(CoII(H2O)2)0.9(CoII(H2O)3)2(WVI3.1O14)(SbIIIWVI9O33)(SbIII2WVI30O106)(H2O)]·53H2O {Co3Sb3W42}. On the basis of the key parameters for the one-pot synthesis strategy of {Bi3W43}, a rational step-by-step approach was developed using the known Krebs-type polyoxotungstate (POT) K12[SbV2WVI22O74(OH)2]·27H2O {Sb2W22} as a nonlacunary precursor leading to the synthesis and characterization of {Sb3W43} and {Co3Sb3W42}. Solid-state characterization of the three new representatives {Bi3W43}, {Sb3W43}, and {Co3Sb3W42} by single-crystal and powder X-ray diffraction (XRD), IR spectroscopy, thermogravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and elemental analysis, along with characterization in solution by UV/vis spectroscopy shows that {Bi3W43}, {Sb3W43}, and {Co3Sb3W42} represent the first main group V heteropolyoxotungstates encapsulating a defect {(WVIO7)WVI4} ({X3W43}, X = BiIII and SbIII) or full {(WVIO7)WVI5} ({Co3Sb3W42}) pentagonal unit. With 43 tungsten metal centers, {X3W43} (X = BiIII and SbIII) are the largest unsubstituted tungstoantimonate- and bismuthate clusters reported to date. By using time-dependent UV/vis spectroscopy, the isostructural representatives {Sb3W43} and {Bi3W43} were subjected to a comprehensive study on their catalytic properties as homogeneous electron-transfer catalysts for the reduction of K3[FeIII(CN)6] as a model substrate revealing up to 5.8 times higher substrate conversions in the first 240 min (35% for {Sb3W43}, 29% for {Bi3W43}) as compared to the uncatalyzed reaction (

We evaluated the influence of blending various renewable polymer grades and amounts to allow for high stretchability during stretching at 800 mm/s to produce polymer tapes with high Young’s moduli E and yield stress σy similar to industrial production of non-degradable synthetic polymers. Renewable polymer blends based on TPS, PBAT, and PLA with high stretchability as well as high E and σy of stretched tapes comparable to high-density polyethylene (PE-HD) and isotactic polypropylene were identified. High stretchability (up to 380%) was facilitated with TPS-PBAT tapes and comparably high E (up to 5000 MPa) and σy (up to 160 MPa) of stretched tapes were obtained for mixtures of different PLA grades resulting in E-moduli exceeding that of PE-HD. A balance of these properties approaching those of synthetic polymers was achieved with PLA-PBAT blends (stretchability: 340%, E: 4500 MPa, σy: 120 MPa).

The use of chemical and energy intensive delignification processes in industrial pulping generates cellulosic fibres that are hydrophilic, hygroscopic and functionally restricted to paper and cardboard applications. Here, we propose a bio-based alternative to chemical pulping utilising herbivores to harvest and grind lignocellulosic materials followed by natural fungal growth to delignify and hybridise them to generate hierarchical composite papers with altered, water-repelling surface properties. These papers comprise cellulose and fungal biopolymers produced by cultivation of T. versicolor and P. ostreatus on elephant manure. Papers with considerably more hydrophobic surfaces were obtained at glucosamine contents as low as 0.1 wt%. Paper tensile strengths and elastic moduli were improved with longer fungal growth periods, spanning several weeks, resulting in comprehensive interfacing of cellulose microfibrils through tough nanoscale fungal chitin-β-glucan networks within the papers. Papers produced from lignocellulosic material colonised with P. ostreatus for 16 weeks exhibited the highest tensile strengths and more hydrophobic surfaces than T. versicolor. Hybridisation of lignocellulose with fungal biopolymers resulting in improved surface and mechanical properties highlights the extended opportunities of fungal delignification bioprocessing and demonstrates the considerable potential of the fungal biorefinery as an economical, and as of yet underexploited technology.

Treatment of polluted water is an important task to secure access to clean water also for future generations. Filters are an efficient means to reject various pollutants on a wide range of size scales either by size-exclusion or electrostatic interaction, respectively. Commonly, filters and membranes from various synthetic materials are employed for these applications. Recently, filters based on renewable (nano) cellulose papers and coatings emerged as sustainable alternative to synthetic materials usually utilized. However, fabrication of such paper network structures from aqueous suspension by filtration processes is a time-consuming process caused by the high water holding capacity of highly hydrophilic and negatively charged nanocellulose fibrils. To optimize the preparation of nanocellulose coated filters, substitution of water by air and thus generating nanocellulose foams that are collapsed onto a substrate would be an appealing approach. Here we present the development of foams from negatively charged TEMPO-oxidized nanocellulose by screening various surfactants and concentrations to generate a foam stable enough to be transferred onto a viscose substrate. Foams were collapsed by oven consolidation, positive pressure filtration, or hot-pressing, respectively. Consolidated filters were tested for their water permeance and rejection of heavy metal ions using copper ions as model system. Very high permeances competitive to commercial filters based on synthetic polymers were achieved. Furthermore, adsorption capacities for copper of up to 70 mg/g were found. This is close to adsorption capacities reported for negatively charged TEMPO-oxidized nanocellulose in conventional batch-wise static adsorption. However, in the current process adsorption takes place during filtration of water through filters in a continuous process which constitutes a tremendous advantage. Graphical Abstract

Polymer/layered silicate composites have gained huge attention in terms of research and industrial applications. Traditional nanocomposites contain particles regularly dispersed in a polymer matrix. In this work, a strategy for the formation of a composite thin film on the surface of a polycaprolactone (PCL) matrix was developed. In addition to the polymer, the composite layer was composed of the particles of saponite (Sap) modified with alkylammonium cations and functionalized with methylene blue. The connection between the phases of modified Sap and polymer was achieved by fusing the chains of molten polymer into the Sap film. The thickness of the film of several μm was confirmed using electron microscopy and X-ray tomography. Surfaces of precursors and composite materials were analyzed in terms of structure, composition, and surface properties. The penetration of polymer chains into the silicate, thus joining the phases, was confirmed by chemometric analysis of spectral data and changes in some properties upon PCL melting. Ultimately, this study was devoted to the spectral properties and photoactivity of methylene blue present in the ternary composite films. The results provide directions for future research aimed at the development of composite materials with photosensitizing, photodisinfection, and antimicrobial surfaces.

Funding Information: The authors thank Prof. Dr. Banik for helpful discussions. Dr. Bacher and Dr. Schiehser are acknowledged for practical support (NMR and GPC). Special thanks to P. Reindl for the AFM measurements. L.V. would like to thank Klassik Stiftung Weimar and the doctoral school ABC&M for financial support. The financial support of the Austrian Biorefinery Center Tulln (ABCT), the Austrian Federal Ministry for Digital and Economic Affairs, and the National Foundation for Research Technology and Development is gratefully acknowledged. The authors are grateful to Borregaard (Norway) and SAPPI (Belgium) for donating CNF. Publisher Copyright: © 2022 The Authors. Small published by Wiley-VCH GmbH The conservation of historical paper objects with high cultural value is an important societal task. Papers that have been severely damaged by fire, heat, and extinguishing water, are a particularly challenging case, because of the complexity and severity of damage patterns. In-depth analysis of fire-damaged papers, by means of examples from the catastrophic fire in a 17th-century German library, shows the changes, which proceeded from the margin to the center, to go beyond surface charring and formation of hydrophobic carbon-rich layers. The charred paper exhibits structural changes in the nano- and micro-range, with increased porosity and water sorption. In less charred areas, cellulose is affected by both chain cleavage and cross-linking. Based on these results and conclusions with regard to adhesion of auxiliaries, a stabilization method is developed, which coats the damaged paper with a thin layer of cellulose nanofibers. It enables the reliable preservation of the paper and—most importantly—retrieval ofthe contained historical information: the nanofibers form a flexible, transparent film on the surface and adhere strongly to the damaged matrix, greatly reducing its fragility, giving it stability, and enabling digitization and further handling.

The need for multifunctional, robust, reusable, and high-flux filters is a constant challenge for sustainable water treatment. In this work, fully biobased and biodegradable water purification filters were developed and processed by the means of three-dimensional (3D) printing, more specifically by fused deposition modelling (FDM).The polylactic acid (PLA) – based composites reinforced with homogenously dispersed TEMPO-oxidized cellulose nanofibers (TCNF) or chitin nanofibers (ChNF) were prepared within a four-step process; i. melt blending, ii. thermally induced phase separation (TIPS) pelletization method, iii. freeze drying and iv. single-screw extrusion to 3D printing filaments. The monolithic, biocomposite filters were 3D printed in cylindrical as well as hourglass geometries with varying, multiscale pore architectures. The filters were designed to control the contact time between filter’s active surfaces and contaminants, tailoring their permeance.All printed filters exhibited high print quality and high water throughput as well as enhanced mechanical properties, compared to pristine PLA filters. The improved toughness values of the biocomposite filters clearly indicate the reinforcing effect of the homogenously dispersed nanofibers (NFs). The homogenous dispersion is attributed to the TIPS method. The NFs effect is also reflected in the adsorption capacity of the filters towards copper ions, which was shown to be as high as 234 and 208 mg/gNF for TCNF and ChNF reinforced filters, respectively, compared to just 4 mg/g for the pure PLA filters. Moreover, the biocomposite-based filters showed higher potential for removal of microplastics from laundry effluent water when compared to pure PLA filters with maximum separation efficiency of 54 % and 35 % for TCNF/PLA and ChNF/PLA filters, respectively compared to 26 % for pure PLA filters, all that while maintaining their high permeance.The combination of environmentally friendly materials with a cost and time-effective technology such as FDM allows the development of customized water filtration systems, which can be easily adapted in the areas most affected by the inaccessibility of clean water.

Due to its unique properties, nano fibrillated cellulose (NFC) has been a popular topic of research in recent years. Nevertheless, literature assessing environmental impacts of NFC production is scarce, especially for using other starting materials than wood pulp. Hence, in this study, a new approach of cascaded use of manure to produce biogas and subsequently use the cellulose containing digestate for NFC production (manure scenario) is compared to the production from Kraft pulp from hardwood chips (wood chips scenario) via life cycle assessment (LCA). To produce comparable outputs (NFC and biogas) in both scenarios a typical Austrian biogas plant with maize silage and pig slurry as input material is included in the wood chips scenario. A proxy approach is used to upscale the manure scenario from laboratory to an industrial scale (except for the pulp to NFC step) to ensure comparability of both scenarios. The impact categories global warming potential (GWP), fossil resource scarcity, freshwater eutrophication, human toxicity, terrestrial acidification (TAP) and terrestrial ecotoxicity potential are analysed referring to the functional unit of 1 kg NFC. Results show that the manure scenario has at least 45% lower impacts in all assessed categories. GWP is 4.41 kg CO

Two penta-coordinate complexes of the general formula [Co(Ln)(NCS)]ClO4, where L1 = {bis[(3,5-dimethyl-1H-pyrazol-1-yl)ethyl]-[(3,4-dimethoxypyridin-2-yl)methyl]}amine and L2 = {bis[(3,5-dimethyl-1H-pyrazol-1-yl)ethyl]-[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]}amine, have been synthesized and thoroughly characterized. Each of the cobalt(ii) atoms is penta-coordinated in the {CoN5} donor set with a distorted square-pyramidal geometry in [Co(L1)(NCS)]ClO4·MeOH (1), while the vicinity of the central atom can be described as a distorted trigonal-bipyramidal geometry in [Co(L2)(NCS)]ClO4 (2) as revealed using the SHAPE analysis. Differences in interatomic parameters among the cobalt(ii) and donor atoms in 1 and 2 have definite impact on the magnetic features of both compounds. The complexes show an easy-axis magnetic anisotropy (D = -38.5 cm-1 for 1 and D = -8.5 for 2), and both complexes reveal a large rhombicity with E/D = 0.21 for 1 and E/D = 0.29 for 2. The ZFS parameters (g, D and E) were also calculated using CASSCF/NEVPT2 methods and they are in good agreement with those determined from experimental data. A frequency dependent out-of-phase susceptibility has been observed in external magnetic field (Bdc = 0.1 T) revealing the following parameters of slow relaxation of magnetization for 1: energy of the spin reversal barrier, Ueff = 16.0 cm-1 (Ueff/kB = 23.0 K) and the relaxation time, τ0 = 1.28 × 10-6 s. In the case of complex 2, no maxima of frequency dependent out-of-phase susceptibility have been observed and thus, the value of Ueff = 17 cm-1 has been estimated using the expression Ueff = |D| × (S2 - 1/4). It has been demonstrated that the degree of substitution and the type of substituents on the pyridyl moieties of the tripodal ligands (L1 and L2) used in these penta-coordinate cobalt(ii) complexes have significant impact on structural and magnetic features.

Two coordination polymers of mono-dimensional doubly bridged-azido-cobalt(II) complexes catena-[Co(2,6-lutidine-N-oxide)(μ1,1-N3)2] (1) and catena-{[Co(μ1,1-N3)2(H2O)2](3-picoline-N-oxide)2} (2), where 2,6-lutidine-N-oxide = 2,6-dimethylpyridine-N-oxide and 3-picoline-N-oxide = 3-methylpyridine-N-oxide, were synthesized, and structurally characterized by single crystal X-ray crystallography. The Co(II) cations in complexes 1 and 2 are penta- and hexa-coordinate, respectively with four μ1,1-bridging azido groups and a terminal 2,6-lutidine-N-oxide molecule in 1 or two trans aqua molecules in 2. Magnetic relaxations in the zero field are consistent with single chain magnetic behavior (SCM) and the ac susceptibility measurements revealed that the weak ferromagnetic exchanges in the two complexes are associated with slow relaxation of magnetization. Complex 2 exhibits metamagnetic transition with an antiferromagnetic phase transition at 12 K at the applied field of 200 Oe.

Contamination of fresh water sources with heavy metal ions constitutes a serious threat to drinking water safety. Treatment of water in order to remove these contaminants, e.g. copper ions, is thus an important task, usually performed by utilizing adsorbents or continuous membrane/filter processes. In particular combinations of these processes, i.e. adsorption or ion-exchange membranes/filters, are potential solutions in this regard. Thereby, materials derived from renewable resources constitute an environmentally benign alternative to traditional adsorption membrane/filter materials. For example, anionic TEMPO-oxidized cellulose nanofibrils (TCNF) were demonstrated to have high affinity towards heavy metal ions but nanopaper membranes made thereof suffer from low permeance and hence limited performance. To achieve high permeance and efficient adsorption of metal ions utilizing pure nanopapers has still not been possible. However, decorating a porous natural fibre substrate with TCNF should allow for high adsorption capacity towards Cu2+ together with high water permeance. We here present natural fibre-nanocellulose composite filters derived from flax and agave fibres, extracted e.g. from tequila residues, decorated with TCNF. The performance of these filters was determined with respect to their permeance and adsorption capacity for copper. It was shown that this new type of filter derived from industrial crop residues is capable of adsorbing high amounts of Cu(II) ions during a continuous filtration process with very high permeances enabled by their highly porous nature.

Agricultural by-products can be upcycled into environmentally-sustainable, inexpensive chitinous materials and nanofibers derived from fungal mycelium for composites, cosmetics, pharmaceuticals and water treatment applications. This study determined the suitability of common agricultural by-products as medium for fungal growth. Growth was measured by quantifying ergosterol, a unique fungal product, in solid and liquid media. The results reveal that fungi grew less on rice hull, sugarcane bagasse and wheat straw agricultural by-products than on commercial wheat grains. However, the liquid agricultural by-product blackstrap molasses facilitated very high biomass production, outperforming the commonly used laboratory nutrient malt extract. Hyphal fusion, sheet formation and hyphal diameter metrics of fungi growing on each substrate were evaluated by SEM to assess suitability for chitin nanofiber production. Utilising these materials offers a cheap, renewable, easily-isolated, and abundant alternative to problematic crustacean chitin that when implemented on a large scale could rapidly upcycle low-value agricultural by-products into high-value chitinous materials.

A dimeric [Cu(μ-4-HOMP)(4-HOMP)(NCS)2]2 (1) and three discrete monomeric complexes [Ni(3-HOMP)2(NCS)2(H2O)2] (2), [Co(3-HOMP)3(N3)3]·H2O (3) and [Zn(4-HOMP)2(NCS)2] (4), (3-HOMP = 3-hydroxymethylpyridine, 4-HOMP = 4-hydroxymethylpyridine) have been isolated and structurally characterized by IR, UV–Vis spectroscopy, XRPD, single crystal X-ray crystallography and Hirshfeld surface analysis as well as thermogravimetric analyses for complexes 1, 2 and 4. In dimeric complex 1 each penta-coordinated Cu2+ center is bridged through N,O-4-HOMP ligands, whereas metal ions in 2 and 3 are located in distorted octahedral geometry with mer-configuration in the azido complex 3. Distorted tetrahedral geometry is observed around Zn2+ in complex 4. The variable temperature magnetic susceptibility measurements of 1 showed very weak antiferromagnetic interaction.

Birch (Betula pendula Roth.) and beech (Fagus sylvatica L.) solid wood and plywood were overmolded with polyamide 6 (PA 6) and polypropylene (PP) to investigate their mechanical properties and interfacial adhesion. In the case of PA 6, maximum tensile shear strengths values of more than 8 to 9 MPa were obtained for birch and beech, respectively. The values are comparable to bond strengths of commercial joints bonded with formaldehyde-containing amino-plastics. Perpendicular to the wood elements, bond strength values of 3 MPa was achieved for PA 6. The penetration of the polymers into the wood structure results in a non-densified interphase and subsequent plastic deformation of the wood structure beyond the interphase. These compressed areas influenced the interfacial adhesion and mechanical interlocking. SEM and XPS analysis revealed different interpenetration behavior of the polymers into the wood structure, with chemical interaction confirmed only for wood and PA 6 but not PP.

We report on the synthesis and characterization of three new nanosized main group V heteropolyoxotungstates KxNay[H2(XWVI9O33)(WVI5O12)(X2WVI29O103)]·nH2O {X3W43} (x = 11, y = 16, and n = 115.5 for X = SbIII; x = 20, y = 7, and n = 68 for X = BiIII) and K8Na15[H16(CoII(H2O)2)0.9(CoII(H2O)3)2(WVI3.1O14)(SbIIIWVI9O33)(SbIII2WVI30O106)(H2O)]·53H2O {Co3Sb3W42}. On the basis of the key parameters for the one-pot synthesis strategy of {Bi3W43}, a rational step-by-step approach was developed using the known Krebs-type polyoxotungstate (POT) K12[SbV2WVI22O74(OH)2]·27H2O {Sb2W22} as a nonlacunary precursor leading to the synthesis and characterization of {Sb3W43} and {Co3Sb3W42}. Solid-state characterization of the three new representatives {Bi3W43}, {Sb3W43}, and {Co3Sb3W42} by single-crystal and powder X-ray diffraction (XRD), IR spectroscopy, thermogravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and elemental analysis, along with characterization in solution by UV/vis spectroscopy shows that {Bi3W43}, {Sb3W43}, and {Co3Sb3W42} represent the first main group V heteropolyoxotungstates encapsulating a defect {(WVIO7)WVI4} ({X3W43}, X = BiIII and SbIII) or full {(WVIO7)WVI5} ({Co3Sb3W42}) pentagonal unit. With 43 tungsten metal centers, {X3W43} (X = BiIII and SbIII) are the largest unsubstituted tungstoantimonate– and bismuthate clusters reported to date. By using time-dependent UV/vis spectroscopy, the isostructural representatives {Sb3W43} and {Bi3W43} were subjected to a comprehensive study on their catalytic properties as homogeneous electron-transfer catalysts for the reduction of K3[FeIII(CN)6] as a model substrate revealing up to 5.8 times higher substrate conversions in the first 240 min (35% for {Sb3W43}, 29% for {Bi3W43}) as compared to the uncatalyzed reaction (, We report on the synthesis and characterization of three new tungsten-based defect {(WVIO7)WVI4}KxNay[H2(XWVI9O33)(WVI5O12)(X2WVI29O103)]·nH2O {X3W43} (x = 11, y = 16, and n = 115.5 for X = SbIII; x = 20, y = 7, and n = 68 for BiIII) or full pentagonal {(WVIO7)WVI5} unit K8Na15[H16(CoII(H2O)2)0.9(CoII(H2O)3)2(WVI3.1O14)(SbIIIWVI9O33)(SbIII2WVI30O106)(H2O)]·53H2O {Co3Sb3W42} encapsulating main group V representatives. With 43 W centers, {Sb3W43} and {Bi3W43} exhibit the highest nuclearity among unsubstituted tungstoantimonates and bismuthates reported to date. The catalytic properties of {Sb3W43} and {Bi3W43} as homogeneous electron-transfer catalysts for the reduction of K3[FeIII(CN)6] to K4[FeII(CN)6] was investigated.

Funding Information: I.S. thanks The Academy of Finland (grant no. 300364) for funding this work. C.D. acknowledges funding from FAPESP (grant 13/07932‐6). P.A.P. thanks the Emil Aaltonen Foundation and Academy of Finland (grant no. 315768) for funding and ESRF for beamtime at beamline D2am (experiment 02‐01‐885). Rita Hatakka is acknowledged for her assistance with the GPC measurements. Work of M.L. was supported by the Jane and Aatos Erkko Foundation. The work is a part of the FinnCERES Bioeconomy ecosystem. Publisher Copyright: © 2021 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH Copyright: Copyright 2021 Elsevier B.V., All rights reserved. Nanoparticle assembly is intensely surveyed because of the numerous applications within fields such as catalysis, batteries, and biomedicine. Here, directed assembly of rod-like, biologically derived cellulose nanocrystals (CNCs) within the template of a processed cotton fiber cell wall, that is, the native origin of CNCs, is reported. It is a system where the assembly takes place in solid state simultaneously with the top-down formation of the CNCs via hydrolysis with HCl vapor. Upon hydrolysis, cellulose microfibrils in the fiber break down to CNCs that then pack together, resulting in reduced pore size distribution of the original fiber. The denser packing is demonstrated by N2 adsorption, water uptake, thermoporometry, and small-angle X-ray scattering, and hypothetically assigned to attractive van der Waals interactions between the CNCs.

Protein functionalized cellulose fibrils were isolated from the tunic of Pyura chilensis and subsequently used to produce protein functionalized cellulose membranes. Bleached cellulose membranes were also obtained and used as reference material. FTIR and Raman spectroscopy demonstrated that the membranes are mostly constituted of cellulose along with the presence of residual proteins and pigments. Protein functionalized cellulose membranes were found to possess ∼3.1% of protein at their surface as measured by X-ray photoelectron spectroscopy. Powder X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis were used to identify and semiquantify the amount of residual sand grains present within the structure of the membranes. The presence of residual proteins was found not to significantly affect the tensile mechanical properties of the membranes. Streaming ζ-potential was used to assess surface charges of the membranes. Below pH 4, nonbleached cellulose membranes possessed highly negative surfaces charges and also significantly less negative surface charges at physiological pH when compared to bleached cellulose membranes. No significant difference was found with respect to growth kinetics of myoblasts at the surface of the membranes for cell culturing times of 48 and 72 h. After 48 h of culture, protein functionalized cellulose-based membranes that possess ∼3.1% of proteins at their surface (H1) were, however, found to promote higher cell density, cell spreading, and more orientated shape cell morphology when compared to the other cellulose-based membranes (H3 and B) evaluated in the present study.

Wood in service requires protection from excessive moisture. Herein, we demonstrate that efficient surface hydrophobization can be provided with small amounts of biobased oils, benefitting from the hierarchical roughness inherent to wood surfaces. The developed technique involves coating spruce wood with surfactant-free emulsions based on tung oil, linseed oil, or a linseed oil-based long oil alkyd resin. The ζ-potential of the emulsions was determined by electrophoretic mobility measurements. X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and spectrophotometry were used to study coated surfaces. XPS measurements confirmed the presence of the tung oil coatings. Tung oil emulsions were effective at concentration levels as low as 0.04 wt % oil content, roughly equivalent to 0.04 g m–2 and led to static water contact angles reaching up to >130°. SEM imaging and AFM measurements provide evidence that the micro- and nanostructures inherent to wood enhance the hydrophobization effect of the obtained coatings. A further benefit of the method lies in only minimal effects of the coating on the surface color and gloss. Thus, the mass-efficient process following several of the principles of green engineering led to improved water repellency while not affecting the visual appearance of the coated wood.

This study reports the potential of TEMPO-oxidized cellulose nanofibrils (T-CNF)/poly(vinyl alcohol) (PVA) coatings to develop functionalized membranes in the ultrafiltration regime with outstanding antifouling performance and dimensional/pH stability. PVA acts as an anchoring phase interacting with the polyethersulfone (PES) substrate and stabilizing for the hygroscopic T-CNF

The utilisation of plant-derived nanoscale cellulosic materials (cellulose nanofibrils, CNF) in tailoring water purification membranes is constantly gaining interest in the context of green-functionalised membrane solutions. However, most of the existing approaches based on renewable and biobased materials suffer from the lack of efficient and scalable processing strategies. Here, we introduce a roll-to-roll membrane modification approach based on thin submicron nanocellulose coatings (400-800 nm) to manufacture anti-biofouling membranes with size and charge dependent selectivity using unit operations compatible with existing industrial lines. We turned a commercial polymeric polyethersulfone (PES) microfiltration membrane into highly hydrophilic and tight membrane structure by applying thin and water-durable cellulose nanofibril layers using cast or spray coating methods. Nanocellulose coated membranes exhibited water permeance values of 80 – 100 LMH/MPa with the highest rejection levels of >90% for Cytochrome C. Furthermore, the nanocellulose layers were able to withstand relatively high filtration pressure levels of 1 MPa, indicating that the selected procedures to improve mechanical integrity i.e. polyethylene imine-based anchoring and acid induced CNF cross-linking were successful. The coated membranes with the thinnest nanocellulose layer exhibited a molecular weight cut-off (MWCO) of 2 kDa for negatively charged polystyrene sulfonate and 14 kDa for neutral dextrane indicating charge selective behaviour. It can be concluded that our nanocellulose coated PES membranes represent nanofiltration membranes and lower boundary of ultrafiltration membranes with clear anti-biofouling performance directly evidenced via systematic bovine serum albumin (BSA) adsorption investigations. Our approach paves the way towards tunable and sustainable water treatment technologies simultaneously opening space for novel biobased solutions in membrane sector.

Cellulosic materials are highly sensitive towards environmental changes such as temperature and especially towards humidity. Besides morphological changes like swelling and/or shrinking, the mechanical properties of pulp fibres and fibre to fibre joints change as well. The current study sets to elucidate the changes and the extent to which elevated or decreased relative humidity (RH) influences the load bearing capacity of individual hardwood and softwood fibres and joints. The device used for the measurements is a micro bond tester with a custom-built humidity chamber in which the humidity can be controlled in a range from 25 to 95% RH. Individual fibres and joints have been tested at 30, 50 and 80% RH after equilibration time of 120 min. The breaking load of individual softwood fibres and joints displayed a maximum breaking load at 50% RH, with the values showing a decreasing trend towards higher or lower RH. In case of hardwoods, no change in the breaking load of either individual fibres or fibre to fibre joints has been observed at different RH.

Four different coordination compounds have been synthesized and structurally characterized in the reaction of aqueous solution of Mn(NO3)2 with pyridine-N-oxide co-ligands in the presence of KNCS, namely: [Mn(2-methylpyridine-N-oxide)(NCS)2]n (1); [Mn(3-methylpyridine-N-oxide)2(NCS)2]n (2), [Mn(4-methylpyridine-N-oxide)2(NCS)2(H2O)2] (3) and [Mn(4-cyanopyridine-N-oxide)2(NCS)2(H2O)]2 (4). Single crystal X-ray crystallography revealed the polymeric nature of the complexes as 2-D and 1-D for 1 and 2, respectively, with doubly μ(N,S) isothiocyanato bridging and μ(O,O) bridging methylpyridine-N-oxide ligands. The metal centers in the dinuclear complex 4 are linked by doubly μ(N,S) isothiocyanato bridges, whereas only terminal ligands are observed in the mononuclear complex 3. The magnetic properties of the complexes 1, 2 and 4 were investigated over the temperature range 2–300 K.

A series of pentacoordinate Co(II) complexes of the composition [Co(bpdmpz)Cl]ClO4 (1), [Co(bpdmpz)Cl]PF6 (2), [Co(bdmpzp)Cl]ClO4·H2O (3), [Co(bdmpzp)Cl]PF6 (4), [Co(tdmpza)Cl]ClO4 (5) and [Co(tdmpza)Cl]PF6 (6) (bpdmpz = bis[(2-pyridylmethyl)-(di(3,5-dimethyl-1H-pyrazolyl)methyl)]amine, bdmpzp = bis[(di(3,5-dimethyl-1H-pyrazolyl)methyl))-(2-pyridylmethyl)]amine and tdmpza = tris[di(3,5-dimethyl-1H-pyrazolyl)methyl)]amine) was prepared and thoroughly characterized. Single-crystal X-ray analyses of complexes 1–5 revealed that they possess very close molecular structures with a distorted trigonal bipyramidal geometry. The static DC magnetic experiments revealed the ZFS parameters pointing out small magnetic anisotropy (with the |D| values lying in a relative narrow range of 4.4–5.7 cm−1) and rhombicity (with the E/D parameters in the range of 0–0.26). The dynamic magnetic data revealed that AC susceptibility is temperature and frequency-dependent for 1, 2 and 3, and thus, these compounds belong to a group of field-induced pentacoordinate Co(II) single-molecule magnets (SMMs). The evaluation of magnetic data was also supported by the CASSCF/NEVPT2 calculations.

Five new metal(II) dicyanamide (dca) complexes with 4-hydroxymethylpyridine (4-OMP) and 4-methoxypyridine (4-MOP) have been synthesized, [Co(dca)2(4-OMP)2]n (1), [Cu(dca)2(4-OMP)2]n (2), [Cu(dca)2(4-MOP)2]n (3), [Cd(dca)2(4-MOP)2]n (4), [Zn(dca)2(4-MOP)2]n (5) and characterized by IR, UV–Vis spectroscopy and single crystal X-ray diffraction. The isostructural polymeric 1-D complexes feature double µ1,5-bridging dicyanamide ligands and terminal 4-OMP or 4-MOP ligands in trans-conformation around the distorted M(II) octahedra. The magnetic properties of complexes 1 and 2 are reported.

Four 1D coordination polymers catena -[Cu(4-HOCH 2 py)(μ 1,1 -N 3 )(μ 1,3 -N 3 )] ( 1 ), catena -[Cu(3-MeOpy) 2 (µ 1,1 -N 3 ) 2 ] ( 2 ), catena -[Cu(2-Br-4-Mepy)(µ 1,1 -N 3 ) 2 ] ( 3 ) and catena -[Cu(μ O,O -2-Cl-6-Menic)(μ 1,1 -N 3 )(MeOH)] ( 4 ) where 4-HOCH 2 py, 3-MeOpy, 2-Br-4-Mepy and 2-Cl-6-Menic represent 4-pyridylmethanol, 3-methoxypyridine, 2-bromo-4-methylpyridine and 2-chloro-6-methyl nicotinate anion, respectively have been synthesized, and structurally and magnetically characterized. Variable temperature magnetic susceptibility measurements over the temperature range 4.5–300 K revealed weak to moderate ferromagnetic coupling on going from complexes 1 ( J = 10.1 cm −1 ) and 3 ( J = 16 cm −1 ) to 4 ( J = 51.1) cm −1 . On the other hand, complex 2 displayed weak antiferromagnetic coupling ( J = −3.82 cm −1 ). The magnetic properties of the complexes are discussed in relation to the structural parameters of the bridging ligands.

The effect of the incorporation during the interfacial polymerization process of copper-oxide (CuO) nanoparticles in thin-film composite (TFC) reverse osmosis (RO) membrane on their antibiofouling and desalinization performance have been studied. Membranes were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), zeta potential and contact angle measurements. Bactericidal tests were performed using Escherichia coli and anti-adhesion properties were confirmed by fluorescence microscopy. Membrane performance using a cross flow cell was evaluated. XRD and SEM–EDX analyses confirmed the incorporation of these nanoparticles into the membrane. Similar contact angle, higher surface roughness and less negatively charged surface on modified membrane compared to that of the pristine membrane were observed. However, an excellent anti-adhesion and bactericidal effect were observed, mainly attributed to the copper toxicity. The desalination performance of the modified membrane showed an important salt rejection with stable water flux. In conclusion, the incorporation of CuO nanoparticles into TFC-RO membranes during the interfacial polymerization process is a potential alternative method to improve the antibiofouling capacities without impairing the performance of the membrane.

Nitrates constitute a severe problem for the quality of potable water. The removal of nitrates from water can be performed utilizing continuouslyoperating cellulose nanopaper ion-exchangers, which so far are unfortunately of only moderate efficiency. Here we demonstrate cationic cellulosenanopapers comprising cellulose nanofibrils carrying a high amount of ammonium groups (1.6 g mmol−1, i.e. 0.62 mmol g−1), which areanticipated to enable efficient removal of nitrate ions from aqueous solutions. Thin nanopapers were shown to have high adsorption capacities.Therefore we prepared low grammage nanopapers using a papermaking process from cellulose nanofibrils prepared from paper mill sludge. Theperformance of these cationic nanopapers was characterized by their permeance, with these new cationic nanopapers having a permeance of morethan 100 L m−2 h−1 MPa−1, which is far greater than the permeance of conventional nanopapers. Furthermore, nitrate ions were successfullyremoved from water by capturing them through adsorption onto the cationic nanopaper by primarily an ion-exchange mechanism. These cationicnanopapers possessed adsorption capacities of almost 300 mg g−1, which is superior to commonly used nanopaper ion-exchangers and batch-wiseapplied adsorbents. Utilization of an industrial side-stream in combination with very good membrane performance demonstrates the use ofresource efficient technologies in an important sector.

Mycelium composites are an emerging class of cheap and environmentally sustainable materials experiencing increasing research interest and commercialisation in the EU and USA for construction applications. These materials utilise natural fungal growth as a low energy bio-fabrication method to upcycle abundant agricultural by-products and wastes into more sustainable alternatives to energy intensive synthetic construction materials. Mycelium composites have customisable material properties based on their composition and manufacturing process and can replace foams, timber and plastics for applications, such as insulation, door cores, panelling, flooring, cabinetry and other furnishings. Due to their low thermal conductivity, high acoustic absorption and fire safety properties outperforming traditional construction materials, such as synthetic foams and engineered woods, they show particular promise as thermal and acoustic insulation foams. However, limitations stemming from their typically foam-like mechanical properties, high water absorption and many gaps in material property documentation necessitate the use of mycelium composites as non- or semi-structural supplements to traditional construction materials for specific, suitable applications, including insulation, panelling and furnishings. Nonetheless, useful material properties in addition to the low costs, simplicity of manufacture and environmental sustainability of these materials suggest that they will play a significant role in the future of green construction. Keywords: Fungal mycelium, Mechanical performance, Insulation properties, Fire safety, Water and termite resistance

This article presents a waterborne nanocellulose coating process to change the surface characteristics and mitigate fouling of commercially available polyethersulfone (PES) microfiltration membranes. An extensive comparative study between nanoporous and nano-textured layers composed of cellulose nanocrystals (CNC) or TEMPO-oxidized cellulose nanofibrils (T-CNF), which were coated on the PES membrane by taking advantage of the electrostatic interactions between the PES substrate, a polyallylamine hydrochloride (PAHCl) anchoring layer, and the nanocellulose functional layer. Coated PES membranes exhibited decreased surface roughness and pore sizes as well as rejection of compounds with a M w above 150 kDa, while the water permeability and mechanical properties of remained largely unaffected. The coatings improved the wettability as confirmed by a reduction of the contact angle by up to 52% and exhibited a higher negative surface charge compared to the uncoated membranes over a pH range of 4–8. A significant reduction in organic fouling was observed for the coated membranes demonstrated by bovine serum albumin (BSA) adsorption studies on T-CNF and CNC surfaces using Quartz Crystal Microbalance with Dissipation monitoring (QCM-D), UV–vis spectroscopy and FTIR mapping after exposing the membranes to dynamic adsorption of BSA. The T-CNF coating exhibited effective antibacterial action against Escherichia coli (E. coli) attributed to the pH reduction effect induced by the carboxyl groups; while CNC coatings did not show this property. This work demonstrates a simple, green, and easy-to-scale layer-by-layer coating process to tune the membrane rejection and to improve antifouling and antibacterial properties of commercially available membranes.

The abstract is available here: https://uscholar.univie.ac.at/o:1218439