Design of biodegradable cellulose filtration material with high efficiency and breathability.

Using respiratory protective equipment is one of the relevant preventive measures for infectious diseases, including COVID-19, and for various occupational respiratory hazards. Because experienced discomfort may result in a decrease in the utilization of respirators, it is important to enhance the material properties to resolve suboptimal usage. We combined several technologies to produce a filtration material that met requirements set by a cross-disciplinary interview study on the usability of protective equipment.

Thermoresponsive Nanocellulose Films as an Optical Modulation Device: Proof-of-Concept.

Flexible optoelectronic technologies are becoming increasingly important with the advent of concepts such as smart-built environments and wearable systems, where they have found applications in displays, sensing, healthcare, and energy harvesting. Parallelly, there is also a need to make these innovations environmentally sustainable by design. In the present work, we employ nanocellulose and its excellent film-forming properties as a basis to develop a green flexible photonic device for sensing applications.

Spinning Approach for Cellulose Fiber Yarn Using a Deep Eutectic Solvent and an Inclined Channel.

We developed a spinning approach for a dope produced by treating softwood pulp with a deep eutectic solvent (DES). The DES enables formation of a sufficiently viscous spinnable gel-like suspension of fibers, which solidifies upon the removal of the DES. This solidification, however, requires a longer time compared to most conventional wet spinning processes.

Effect of Surfactant Type and Sonication Energy on the Electrical Conductivity Properties of Nanocellulose-CNT Nanocomposite Films.

We present a detailed study on the influence of sonication energy and surfactant type on the electrical conductivity of nanocellulose-carbon nanotube (NFC-CNT) nanocomposite films. The study was made using a minimum amount of processing steps, chemicals and materials, to optimize the conductivity properties of free-standing flexible nanocomposite films. In general, the NFC-CNT film preparation process is sensitive concerning the dispersing phase of CNTs into a solution with NFC.

Cyclodextrin-Functionalized Fiber Yarns Spun from Deep Eutectic Cellulose Solutions for Nonspecific Hormone Capture in Aqueous Matrices.

A wood based yarn platform for capturing pharmaceutical molecules from water was developed. Cellulose fiber yarns were modified with cyclodextrins, and the capture of 17α-ethinyl estradiol (EE2), a synthetic estrogen hormone used as contraceptive, from water was tested. The yarns were prepared by spinning a deep eutectic solution (DES) of cellulose in choline chloride-urea.

The effect of cellulose molar mass on the properties of palmitate esters.

Nowadays one of the growing trends is to replace oil-based products with cellulose-based materials. Currently most cellulose esters require a huge excess of chemicals and have therefore, not been broadly used in the industry. Here, we show that decreasing the molar mass of cellulose by ozone hydrolysis provides cellulose functionalization with less chemical consumption.

Hydrothermal carbonization of pulp mill streams.

The progress of the conversion, the yield, the structure and the morphology of the produced carbonaceous materials as a function of time were systematically studied with pyrolysis-GC/FID and FESEM microscope. The conversion of galactoglucomannan, bleached kraft pulp and TEMPO oxidized cellulose nanofibrils followed the reaction route of glucose being slower though with fibrous material, higher molar mass and viscosity. The conversion of kraft lignin was minor following completely different reaction route.

Simultaneous bench scale production of dissolving grade pulp and valuable hemicelluloses from softwood kraft pulp by ionic liquid extraction.

Ionic liquid extraction of wood pulp has been highlighted as a highly potential new process for dissolving pulp production. Coproduction with a polymeric hemicellulose fraction was demonstrated in bench scale from softwood kraft pulp using extraction with the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIM OAc) and water. In total, the recovered pulp and hemicellulose fraction together yielded 95.

Production and applications of carbohydrate-derived sugar acids as generic biobased chemicals.

This review considers the chemical and biotechnological synthesis of acids that are obtained by direct oxidation of mono- or oligosaccharide, referred to as sugar acids. It focuses on sugar acids which can be readily derived from plant biomass sources and their current and future applications. The three main classes of sugar acids are aldonic, aldaric and uronic acids.

Fabrication of electrospun poly(D,L lactide-co-glycolide)80/20 scaffolds loaded with diclofenac sodium for tissue engineering.

Background: Adaptation of nanotechnology into materials science has also advanced tissue engineering research. Tissues are basically composed of nanoscale structures hence making nanofibrous materials closely resemble natural fibers. Adding a drug release function to such material may further advance their use in tissue repair.

Synthesis and characterization of copolyanhydrides of carbohydrate-based galactaric acid and adipic acid.

A series of copolyanhydrides, consisting of 2,3,4,5-tetra-O-acetylgalactaric acid (AGA) and adipic acid (AA) as monomer units, was polymerized. Synthesis of AGA monomer consisted of two steps. First, O-acetylation of galactaric acid secondary hydroxyl groups was performed using acetic anhydride as a reagent.

Nanofibrous chitosan-polyethylene oxide engineered scaffolds: a comparative study between simulated structural characteristics and cells viability.

3D nanofibrous chitosan-polyethylene oxide (PEO) scaffolds were fabricated by electrospinning at different processing parameters. The structural characteristics, such as pore size, overall porosity, pore interconnectivity, and scaffold percolative efficiency (SPE), were simulated by a robust image analysis. Mouse fibroblast cells (L929) were cultured in RPMI for 2 days in the presence of various samples of nanofibrous chitosan/PEO scaffolds.

Wood-derived olefins by steam cracking of hydrodeoxygenated tall oils.

Tall oil fractions obtained from Norwegian spruce pulping were hydrodeoxygenated (HDO) at pilot scale using a commercial NiMo hydrotreating catalyst. Comprehensive two dimensional gas chromatography (GC×GC) showed that HDO of both tall oil fatty acids (TOFA) and distilled tall oil (DTO) produced highly paraffinic hydrocarbon liquids. The hydrotreated fractions also contained fatty acid methyl esters and norabietane and norabietatriene isomers.

The use of N,N'-diallylaldardiamides as cross-linkers in xylan derivatives-based hydrogels.

N,N'-Diallylaldardiamides (DA) were synthesized from galactaric, xylaric, and arabinaric acids, and used as cross-linkers together with xylan (X) derivatives to create new bio-based hydrogels. Birch pulp extracted xylan was derivatized to different degrees of substitution of 1-allyloxy-2-hydroxy-propyl (A) groups combined with 1-butyloxy-2-hydroxy-propyl (B) and/or hydroxypropyl (HP) groups. The hydrogels were prepared in water solution by UV induced free-radical cross-linking polymerization of derivatized xylan polymers without DA cross-linker (xylan derivative hydrogel) or in the presence of 1 or 5 wt% of DA cross-linker (DA hydrogel).

Tailoring of the hierarchical structure within electrospun fibers due to supramolecular comb-coil block copolymers: polystyrene-block-poly(4-vinyl pyridine) plasticized by hydrogen bonded pentadecylphenol.

Previously we demonstrated hierarchical self-assembly and mesoporosity in electrospun fibers using selected polystyrene--poly(4-vinylpyridine) (PS--P4VP) diblock copolymers with hydrogen-bonded 3--pentadecylphenol (PDP), which rendered distorted spherical P4VP(PDP) domains within the PS matrix, internal lamellar order within the P4VP(PDP) domains, and allowed distorted spherical pores by removing PDP (. 2005, , 1048). Here we study whether the internal structure of electrospun fibers can be systematically tailored by varying the compositions of PS--P4VP(PDP).