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Higher-order systems found in nature continue to be a source of inspiration for designing highly functional artificial systems. However, compositing these systems requires a precise understanding of how the components required can affect final desired responses. This non-trivial task is daunting and therefore will require a multiplicity of approaches elaborated under the umbrella of compositomics, a proposed –omics cluster dedicated to fabricating green materials through modeling, systems thinking, and machine learning. [ABSTRACT FROM AUTHOR]

Low-quality cotton fibers are a low-value waste material within the cotton industry. Upcycling and transforming into high-value materials are highly desired. This study investigates upcycling fibers into hydrogel biosorbents and assesses their efficacy in dye adsorption. An effective gelation approach was employed via simply dropping droplets of suspension mixture of sodium alginate and fibers into acidic bath. Resulting composite hydrogel beads were utilized for dye removal. Composite beads successfully immobilized less than 70 wt% of fibers and achieved a significant improvement in thermal stability. Composite beads with 50 wt% fibers and alginate showed no decrease in methylene blue adsorption capacity. This outcome was unexpected considering the lower dye adsorption capacity of fibers than alginate, particularly notable since it indicated that reduced quantities of the more costly sodium alginate were sufficient to achieve comparable dye adsorption capacity. Mechanistic study unveiled that both the loose crosslinking structure and the electrostatic forces were responsible for the unexpected high adsorption capacity of 50% fiber-alginate. This study reports a promising, innovative and effective upcycle strategy for the first time that can transform fibers into high-value biosorbents without compromising dye adsorption capability. [ABSTRACT FROM AUTHOR]

Chitin–clay composite hydrogels were successfully fabricated through a facile alkali and freeze treatment. Systematic structure–property relationships based on different compositions of the composite systems were determined. It was found that addition of clay considerably increased the thermal stability as indicated by increases in initial decomposition temperature compared to pure chitin. The increase in activation energy of degradation calculated by the Coats–Redfern method supported the thermal stabilization. For other properties, clay decrease water content, swelling ratio and porosity of gel materials. The morphology indicated they underwent a transition from clay clusters as the dispersive phase to clay flakes as the matrix. Wide angle X-ray scattering results suggested that clay-hindered crystallization of chitin. Fourier-transform infrared spectroscopy results indicated that freezing induced specific interactions while incorporation of clay-hindered deacetylation. This work provides a simple and green method to prepare chitin–clay composites gel materials. [ABSTRACT FROM AUTHOR]

The perception of the chemical field by the public has degraded proportionally with the growth of the industry. Chemical plants, as the largest source of chemical production and storage, have significant impact on the levels of chemophobia harbored in our society. Specifically, chemical disasters not only create significant loss, but they also work to propel the common distrust of chemistry in a dangerous direction. Repeated mishandling of distinct compound types coupled with disasters across the world harming thousands sends the message that our industry is unsafe and out of control. The preventable nature of these events demands that we seek means to curb the errors behind these major events within the industry required to support their importance to our economy and way of life in the United States. Additionally, we must strive to use educational approaches and constant dialogue as tools to surmount unfounded fears and augment public understanding of the nature and value of chemistry. [ABSTRACT FROM AUTHOR]

The US, which historically has been a major producer of hemp, has recently reintroduced industrial hemp production. The idea is to provide agriculture and farming communities with new economic opportunities (2018 Farm Bill) to replace lost income from formerly more profitable cash crops such as tobacco. Industrial hemp is a scalable crop that could provide significant economic and environmental benefits; however, the true valorization of industrial hemp will hinge on significant innovation and the development of high-value applications. Utilization of the whole hemp plant may be the key to attaining economic, environmental, and social sustainability. Further, strong community outreach and education is required to overcome the stigma attached with industrial hemp due to its morphological and genetic similarities to its psychoactive-rich (> 0.3% tetrahydrocannabinols (THC)) analogue. This editorial identifies critical research, educational, and community outreach platforms to develop a robust US industrial hemp program, with a goal to enable the renaissance of this miracle crop. Collaboration of the forest sector, universities, and industries is urged for the establishment of a center or consortium that fosters the future advances amongst more productive hemp cultivars, local farming practices, and bioproducts development for economic outlets for this miracle crop. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new pathway for sustainable packaging materials was engineered by formulating multilayer CNF/CNC barrier coatings. • CNF and CNC synergistically enabled high oil and grease resistance (a kit rating of 11) comparable to fluorochemicals. • A significant reduction in oxygen transmission rate was demonstrated (∼by a factor of about 260) compared to uncoated paper. • Sustainable biomaterials are relevant to society's ongoing efforts to improve health, safety, and environmental stewardship. Abstract Cellulose derivatives such as cellulose nanofibers (CNF) and cellulose nanocrystals (CNC) have enormous potential to reduce or replace petroleum and fluorochemicals for food and other packaging applications. CNFs have been studied for their excellent oxygen and gas barrier properties; however, their performance rapidly decreases in the presence of moisture and higher humidity. CNCs are less sensitive to moisture due to their highly crystalline nature; however, coatings and films made of CNCs are much more prone to fracture due to their high brittleness. Our work demonstrates a unique composite barrier coating system of CNF and CNC that synergistically enables oil and grease resistance (a kit rating of 11) comparable to fluorochemicals. It also demonstrates a significant increase in air resistance (∼by a factor of about 300), and a reduction in oxygen transmission rate (∼by a factor of about 260) compared to uncoated paper. The improvements in oil and gas barrier properties were evaluated with respect to the molecular, chemical, and structural properties of the developed coatings. [ABSTRACT FROM AUTHOR]

The aim of the current work was to develop and study a paper additive system that endows recycled paper fibers with strong mechanical and antimicrobial properties. Five different types of modifying agents including succinic acid, carboxymethyladipic acid, butanetetracarboxylic acid, ethylenediaminetetraacetic acid, and diethylenetriaminepentaacetic acid (DTPA) were reacted with soy flour. Approximately 2% modified soy flour additive by mass relative to a old corrugated container (OCC) pulp slurry was mixed before generating a two-dimensional hand sheet for physical testing. DTPA-modified soy-flour-treated OCC pulp displayed better tensile relative to the results from the use of other modifying agents. Soy flour was treated with different DTPA concentrations, times, temperatures, and pH values to determine the optimal modification reaction conditions. Afterward, the DTPA-soy flour was complexed with chitosan to decrease the biodecomposition of soy protein, improve its incorporation into an OCC matrix, and increase interfiber bonding. The optimal conditions were found to be 20% DTPA, 120 °C, 3 h, and pH 10. Last, a low dosage of DTPA-soy flour/chitosan-OCC pulp was found to kill ∼95% of tested bacteria. [ABSTRACT FROM AUTHOR]

Although many effects to design smart self-healing sustainable hydrogels with sensitivity to multi-environmental stimuli have been documented, a facile fabrication of stimuli-responsive hydrogels with improved mechanical properties remains challenging. Here, smart self-healing sustainable hydrogels containing soy protein polymer (SPP) and/or graphene nanoplatelets (GNP) were fabricated using "slime" chemistry. The composites hydrogels exhibited impressive self-healing behavior and high ductility under mechanical stimuli, pH-modulation, and thermo sensitivity. An unexpected synergistic reinforcing effect was achieved via combination of SPP and GNP (ternary composite); while the usage of mere SPP and GNP (binary composite) even weakened the gel modulus. Surprisingly improved resistance to gel flowability caused by external heat stimuli was also achieved in the same system. The reinforcing mechanism was attributed to the interactions between SPP and GNP to restore the crosslinking structures. This character also offered merits to the higher viscosity of ternary composite system and thereby resulted in improved heat resistance. [Display omitted] • Self-healing composites hydrogels exhibited multi-stimuli responses. • Synergistic reinforcing effect and resistance to gel flowability were achieved. • The improved mechanisms were proposed. [ABSTRACT FROM AUTHOR]

The integration of combinatorial green chemistry (CGC), a more benign approach to combinatorial chemistry, with environmental life cycle assessment (LCA) methodologies as an improved process development methodology is discussed. It is expected that the CGC approach will require less labor and result in more globally optimized assay results, leading to more optimized unit process design. The technique utilizes chemical assay stage information to rapidly predict globally optimized process conditions based on techno-economic and LCA indicators. A simplified kraft pulping case study of the application of CGC-LCA is demonstrated herein, but CGC analyses could be applied to virtually any chemical-based project development and implementation project. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the chemical structure and morphology of cellulose nanocrystals. Applications of cellulose nanocrystals in nanocomposite materials include casting-evaporation processing and sol-tel processing. The authors explained the intramolecular hydrogen-bonding network in a representative cellulose structure.

Approximately 89 million metric tonnes of organic chemicals and lubricants are produced annually in the United States (T.M. Carole, J. Pellegrino, and M.D. Paster. Appl. Biochem. Biotechnol. 115, 871 (2004)). The majority of these materials are fossil fuel based and may load the environment during use and at the end of their life cycle. Issues, such as disposal, pollution, and degradation, must be considered and weighed. As a result, the need to decrease pollution caused by petrochemical usage is currently impelling the development of green technologies. It is virtually inarguable that the dwindling hydrocarbon economy will eventually become unsustainable. The cost of crude oil continues to increase, while agricultural products see dramatic decreases in world market prices. These trends provide sufficient basis for renewed interest in the use of biomass as a feedstock and for the development of a carbohydrate-based economy as the logical alternative to fossil fuel resources. [ABSTRACT FROM AUTHOR]

Chlorine dioxide delignification (D 0 ) modifies kraft residual lignin by oxidizing phenolic groups to both quinone and muconic acid structures. Alkaline extraction (E), in addition to removing solubilized lignin, converts quinone moieties to polyphenols. These polyphenols are easily oxidized by oxygen in an (EO) stage or by ClO 2 in a D 1 stage to hydroxyquinones (∼⃒1.8 mmol/g lignin). Pulps treated by D 0 E consume considerably more ClO 2 in the D 1 than D 0 (EO), and have lower bleachability, as was quantified by a simple bleaching model. Both D 0 E and D 0 (EO) pulps approach a common brightness ceiling (∼⃒83 ISO) when excess ClO 2 is applied. Examination of the post‐D 1 b* values indicates that D 0 E and D 0 (EO) also have similar asymptotic b* values (∼⃒6), indicating that both pulps have similar residual chromophores. Hydroxyquinone structures appear to be eliminated in the D 1 stage for D 0 (EO) pulps, and at high ClO 2 levels for D 0 E pulps. [ABSTRACT FROM AUTHOR]

Peroxide‐reinforced extractions ((EP) or (EOP)) of D 0 pulps lower both post‐extraction kappa numbers and Klason lignins more than either E or (EO). An oxygen‐reinforced extraction (EO) results in lower kappa numbers, but affords comparable Klason lignins as an E stage (∼⃒1.2% lignin). Quinonoid structures in (EO) stocks are similar to those of the D 0 pulps (1.7 mmol/g lignin). Peroxide inclusion in EP and EOP appeared to eliminate both quinonoid and muconic acid moieties. These observations were confirmed with (EP) treatment of reference pulps (periodate or periodate‐peracetic acid) that contain significant levels of either quinones or muconic entities. The D 1 bleachability order, from easiest to hardest, was D 0 (EOP)>D 0 (EP)≈D 0 (EO)>D 0 E. An identical order was found for how quickly the yellow chromophores (b* value) are eliminated. All extracted pulps, regardless of the type of extraction employed, approach a common D 1 asymptotic brightness (∼⃒86 ISO) and b* value (∼⃒4.2) when excess ClO 2 is applied. The main difference among these pulps was how quickly the asymptotic limits are approached as a function of ClO 2 consumed. The bleachability study indicates that various extracted pulps have similar residual D 1 chromophores limiting the brightness ceiling. [ABSTRACT FROM AUTHOR]

Abstract: We have imparted magnetic susceptibility to lignocellulosic fibers by adding iron powder in a heterogeneous manner to the fibers during hydrogen peroxide bleaching chemistry. We have therefore generated carboxylic acid groups in the fibers by deliberately inducing cellulose degradation through Fenton catalysis of the hydrogen peroxide during the chemical oxidation process at a specified level of iron. The iron particles consequently have an exposed layer of iron oxide that allows ionic neutralization of the negatively charged fiber acid groups. After removal of non-attached, excess iron, these fibers have been cast into two-dimensional sheets with two different original iron concentrations and tested for physical and chemical properties. Physical tests included tensile, zero-span tensile, caliper, and surface resistivity. Chemical tests included surface charge, lignin content (kappa) and viscosity. SEM and ICP were also conducted. Remarkably, the magnetically susceptible sheets with incorporated iron were able to retain a tensile strength similar to the unbleached sheets despite attenuation in fiber strength. This is likely due to a chemical refining phenomenon which allowed for increased fiber–fiber bonding. The introduction of the retained iron also significantly alters the surface resistivity of the paper sheets. Such fibers may have a use in applications where charge conduction or dispersion is necessary. [Copyright &y& Elsevier]

A photochemical approach for the delignification of lignocellulosics, specifically Southern kraft softwood pulp, was adopted to provide insight into the nature of the general oxidative chemistry leading to lignin removal and carbohydrate (cellulose) degradation. This is the first paper that primarily provides a systematic investigation of the singlet oxygen photochemistry of kraft pulp, in which Rose Bengal (RB) was employed as the photosensitizer to degrade lignin, and secondarily describes the resultant properties of the pulp. The oxidative chemistry was efficient until approximately 50% of the native lignin polymer remained, at which point the carbohydrate component was not exempt from depolymerization reactions. This study examined the influence of lignin chemical characteristics and a general metal-based radical inhibitor on the reactivity of singlet oxygen. In general, the oxidative chemistry obtained in this study from singlet oxygen was not unlike what has been observed in ground state oxygen reactions. [Copyright &y& Elsevier]

The residual lignins from pulps and effluent lignins from oxygen delignification effluents were characterized using pyrolysis – gas chromatography – mass spectrometry in the presence of tetramethylammonium hydroxide. The results indicated that oxidation under alkali oxygen conditions can induce fragmentation in lignin and produce more acid groups, but the lignin maintains most of its C6–C3 units. Oxygen delignification also led to a decrease in diphenyl structures in the residual lignin and an enrichment in concentration of lignin carbohydrate complex structures. [ABSTRACT FROM AUTHOR]

Two southern pine kraft pulps with kappa numbers of 30.0 (SW1-0) and 48.0 (SW2-0) were oxygen delignified by 30–60% by varying the reaction temperature (78–110°C) and charge of sodium hydroxide (1.6–4.4%). O-bleachability was found to be correlated to the incoming kappa number and charge of sodium hydroxide employed. In general, a lower charge of caustic and a higher brownstock kappa number improved pulp bleachability. The residual lignin in the brownstocks and O-delignified kraft pulp samples was isolated and characterized by 13C and 31P NMR. 13C NMR analysis of the residual lignin samples indicated that the post-oxygen delignified pulps were enriched with α-carbonyl groups and carboxylic acid groups. The content of β-O-aryl structures was increased by 23–36% depending on the extent of oxygen delignification. The post-oxygen delignified pulps were also shown to have increased substituted aryl carbons. 31P NMR indicated that the relative content of condensed phenolic units increased by 9–20% after the oxygen delignification, depending on the severity of the O-stage. This observation was probably due to the accumulation or formation of 5,5-biphenyl structures in the process. The physical strength properties of brownstock and post-oxygen delignified pulps were assessed in terms of zero-span strength, tensile strength, tear strength, and burst strength. Oxygen delignification led to a slight increase in the curls and kinks of the pulp fibers. The O-stage was shown to cause a 4.8–15.6% decrease in zero-span strength. In contrast, oxygen delignification increased tensile strength. This result could be explained as the improvement of fiber bonding after the oxygen bleaching. [ABSTRACT FROM AUTHOR]

Untreated and acetylated hydrogen peroxide-bleached aspen chemithermomechanical pulp (CTMP) was subjected to accelerated light-induced aging in various atmospheres (argon, ambient, or oxygen). The photochemical changes that took place during irradiation were followed by solid-state UV/VIS diffuse reflectance spectroscopy. The degree of photoyellowing of the untreated CTMP decreased when the air in the surrounding atmosphere was replaced with oxygen-free argon. The decrease was only moderate, indicating that atmospheric oxygen is not of sole importance for the light-induced discoloration or that only a trace amount of oxygen (strongly adsorbed to the fiber material) is necessary to cause discoloration. Acetylation clearly diminished the kinetics of photoyellowing in all atmospheres resulting in substantially less absorption in the entire visible range (λ > 400 nm). However, the development of chromophores was attenuated in an oxygen-enriched atmosphere, suggesting that oxygen is important for the color-retarding or photobleaching reactions of acetylated lignocellulosic materials. Independently of the degree of acetylation and the surrounding atmosphere, irradiation with UV/VIS fluorescent lamps generated an apparent absorption maximum around 360 nm with a shoulder at approximately 420 nm. [ABSTRACT FROM AUTHOR]

In the quest to enhance the performance of natural fiber-reinforced polymer composites, achieving optimal dispersion of fiber materials within a polymeric matrix has been identified as a key strategy. Traditional approaches, such as the surface modification of natural fibers, often necessitate the use of additional synthetic chemical processes, presenting a significant challenge. In this work, taking poly (acrylonitrile–styrene–acrylic) (ASA) and bamboo fiber (BF) as a model system, we attempt to use the elastomer-chlorinated polyethylene (CPE) as a compatibilizer to tailor the mechanical properties of ASA/CPE/BF ternary composites. It was found that increasing CPE content contributed to more remarkable reinforcing efficiency, where composite with 15 phr CPE exhibited a nearly four-fold increase in reinforcing efficiency of tensile strength (20 %) compared with that of composite system without CPE (4.1 %). Such improvement was ascribed to the compatibilizing effect exerted by CPE, which prevented the aggregation of BF within polymeric matrix. Surface properties suggested the stronger interface between CPE and BF compared to that between ASA and BF and thereby contributed to the compabilizing effect. Since no chemical process was involved, it is suggested that the introduction of elastomer to be a universal, green and sustainable approach to achieve the reinforcement. [ABSTRACT FROM AUTHOR]

In the quest to enhance the performance of natural fiber-reinforced polymer composites, achieving optimal dispersion of fiber materials within a polymeric matrix has been identified as a key strategy. Traditional approaches, such as the surface modification of natural fibers, often necessitate the use of additional synthetic chemical processes, presenting a significant challenge. In this work, taking poly (acrylonitrile–styrene–acrylic) (ASA) and bamboo fiber (BF) as a model system, we attempt to use the elastomer-chlorinated polyethylene (CPE) as a compatibilizer to tailor the mechanical properties of ASA/CPE/BF ternary composites. It was found that increasing CPE content contributed to more remarkable reinforcing efficiency, where composite with 15 phr CPE exhibited a nearly four-fold increase in reinforcing efficiency of tensile strength (20 %) compared with that of composite system without CPE (4.1 %). Such improvement was ascribed to the compatibilizing effect exerted by CPE, which prevented the aggregation of BF within polymeric matrix. Surface properties suggested the stronger interface between CPE and BF compared to that between ASA and BF and thereby contributed to the compabilizing effect. Since no chemical process was involved, it is suggested that the introduction of elastomer to be a universal, green and sustainable approach to achieve the reinforcement. [ABSTRACT FROM AUTHOR]

• Natural polymers increased the reswelling capacity of polyvinyl alcohol xerogels. • Salt treatment considerably improved both reswelling capacity and thermal stability. • A mechanism of improved reswelling capacity was proposed. Deswelling and reswelling behaviors of polyvinyl alcohol (PVOH) gel systems were studied in which natural polymers promoted reswelling capacity of PVOH gels, while salt (NaCl) solutions de-swelled the hydrogels but improved the reswelling performance. Thermogravimetric analysis (TGA) results indicated that the salt treatment considerably improved the thermal stability. Differential scanning calorimetry (DSC) results indicated that the salt treatment hindered crystallization of all the systems except the urea system. The improved reswelling capacity might be attributed to changes in the crystalline region caused by the salt. [ABSTRACT FROM AUTHOR]

Chitin derived from crustacean biomass has great potential for the production of eco-friendly materials. However, one challenge is its insolubility in regular solvents. Herein, the gelation of chitin alkali suspension was induced via freeze-thawing approach. The as-prepared hydrogels with/without dialysis treatment were freeze-dried into solid foams to display "dry durian fruit" appearance. It was found that dialysis did influence the properties, in which the dialyzed samples exhibited superior water content, swelling ratio, porosity, thermal stability, and smoother surface morphological results. Moreover, the dialyzed chitin foams exhibited nearly the same level of thermal stability compared to chitin powder. With respect to formation mechanisms, we propose that alkali treatment swells chitin and the freezing process deconstructed and weakened H-bonding, while the weakened H-bonding residue self-assembly contributed to hydrogel formation. This research represents a simple and green route for converting chitin suspension to gel materials. Unlabelled Image • A simple and green strategy can process insoluble chitin powder into a hydrogel and solid foams. • The as-prepared chitin foams exhibit almost the same level of thermal stability to pure chitin powder. • A possible gel formation mechanism is also proposed. [ABSTRACT FROM AUTHOR]

It is ironic to think that the venerable pulp and paper industry is now considering ways to degrade cellulose. This notion can be understood as a way that the industry can face a protracted downturn in profitability and ever-mounting socio-economic pressures to enhance the efficiency of biofuels production. Many approaches have been recently taken to deconstruct cellulosic biomass, but this Editorial explores one key that may start to explain the increasing momentum in the biofuels community - biotechnology. Two approaches appear to be possible as scientists search for an effective way to unzip cellulose to its key constituents through the use of biotechnology. On the one hand, there are efforts to re-engineer the chemical composition of the tree, rendering it more digestible by enzymes and decreasing the need for mechanical or chemical pretreatment. On the other hand, what we are learning about lignocellulose biosynthesis can be of potential help in designing more efficient systems to essentially reverse that process. [ABSTRACT FROM AUTHOR]

Citric acid (CA) was used for the hydrothermal carbonization (HTC) of cellulose nanofiber and found to exert remarkable effects on the chemistry and physical aspects of the product distribution. More specifically, the morphology, yield, elemental and proximate composition, chemical functional groups, thermal properties and surface properties of the resultant hydrochars were studied extensively. The morphological properties of the final char were the singularly most surprising and unique finding of this study. The cellulose nanofiber hydrochars were contrasted to hydrochars from bleached softwood pulp, having a similar composition with the former, to pinpoint the role of nano-dimensions. Without the presence of CA, the pulp hydrochar lacked several of the spherical dimensions shown in the nanocellulose; however, and unexpectedly, the presence of CA caused a homogenization of the final product distribution for both samples. Finally, thermally stable and high surface area hydrochars were obtained when the hydrochar was rinsed with acetone. [ABSTRACT FROM AUTHOR]

Magnetic lignin-based adsorbent (MLA) was successfully fabricated to remove methyl orange dye from aqueous solution. The synthesized MLA was characterized by means of Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). In the process of adsorption, influence factors and recycling performance were considered, and the adsorption mechanisms such as isotherm and kinetics were investigated. The result showed that the equilibrium data was consisted with the Langmuir model with a maximum adsorption capacity of 85.0 mg/g. The adsorption kinetics followed a pseudo-secondorder model. Based the adsorption performance, MLA showed good recyclability. Therefore, these results demonstrate that MLA could offer a great potential as an efficient and reusable adsorbent in the wastewater treatments. [ABSTRACT FROM AUTHOR]

Transforming waste materials into biosorbent offers a valuable solution for cost-effective water decontamination while simultaneously promoting waste upcycling. This study focused on the gelation of alginate calcium (AC) and alginate acid (AA) in recycling waste cotton linters (WCL) to create composite hydrogels for dye removal. Both hydrogel systems effectively incorporate WCL, displaying an impressive 80 wt% WCL entrapping capacity in the composite hydrogels. The presence of WCL leads to a fascinating volume expansion phenomenon, particularly noticeable in AC composite systems after freeze-drying. Additionally, the composite hydrogels demonstrate efficient adsorption of methylene blue (MB), ranging from 5 to 22 mg/g in MB dye solution (30 mg L−1), and exhibit good compatibility with various adsorption kinetic models. However, AC composite systems outperform AA composite systems and display higher MB adsorption capacity, faster adsorption rate, and more consistent performance. Mechanistic studies reveal that electrostatic forces contribute to volume expansion and dye adsorption, while the denser crosslinking structure and more abundant carboxylate groups in the AC composite system contribute to its superior performance. Our current study not only establishes the criteria for selecting proper alginate system as bio-composite hydrogel matrices, but also provides a sustainable "waste treat waste" upcycling strategy. [Display omitted] • Waste cotton linter was upcycled as alginate composites gel biosorbents for dye removal. • Alginate calcium composites beads display higher absorption capabilities than alginate acid. • Interesting volume expansion after freeze-drying was observed in alginate calcium systems. • Possible mechanisms were proposed and discussed. [ABSTRACT FROM AUTHOR]

The challenge in energy depletion and environmental pollution urgently demands green and sustainable materials as a new material application platform. Nanocellulose (NC) derived from abundant and renewable resources has been considered as a versatile and sustainable substrate and scaffold to engage various applications. Recently, design and fabricate conductive polymers (CPs)/NC composites as functional electronic devices have received tremendous attention. In this mini review, we start with a brief introduction about the category of nanocellulose, CPs and the preparation strategy of CPs/NC conducive composites followed by discussing the factors that determine the electrical conductivity. Then, we reviewed different CPs/NC composites systems and cited representative electronic application examples including sensors, supercapacitors, lithium-ion batteries. Finally, we proposed current challenges, existing problems and further perspectives and opportunities of CPs/NC conductive composites. [ABSTRACT FROM AUTHOR]

The co-editors of BioResources note the completion of our first ten years. We think that the journal can be judged as a success based on having achieved an impact factor of about 1.4 each year since 2009 and having reached a publication rate of about 700 articles per year. We strive to be a "people's journal" serving scientists, students, and society. We plan to continue emphasizing editorial pieces and review articles, which supplement our main service of publishing peer-reviewed articles dealing with the science of lignocellulosic materials, chemicals, and their uses. We also support undergraduate scholarship in our academic department, including tuition payment, opportunities for pre-editing work, and support for undergraduates to attend conferences, etc. [ABSTRACT FROM AUTHOR]

Society's wish list for future packaging systems is placing some daunting challenges upon researchers: In addition to protecting contents during storage and shipping, the material must not bio-accumulate, and it should be readily recyclable by using practical processing steps. This article considers strategies employing bio-based plastics and reviews published information relative to their performance. Though bioplastics such as poly(lactic acid) (PLA) and poly(hydroxybutyrate) (PHB) can be prepared from plant materials, their default properties are generally inferior to those of popular synthetic plastics. In addition, some bioplastics are not easily decomposed in soil or seawater, and the polymers can undergo chemical breakdown during recycling. This review considers strategies to overcome such challenges, including the use of biodegradable cellulose-based reinforcing particles. In addition to contributing to strength, the cellulose can swell the bioplastic, allowing enzymatic attack. The rate-controlling step in bioplastic degradation also can be abiotic, i.e. not involving enzymes. Though there is much more work to be done, much progress has been achieved in formulating bioplastic composites that are biodegradable, recyclable, and higher in strength compared to the neat polymer. Emphasis in this review is placed on PLA and PHB, but not to the exclusion of other bioplastic matrix materials. [ABSTRACT FROM AUTHOR]

Lignin is a by-product of the pulp and paper industry that can be precipitated by acidification from black liquor as a potential feedstock for valuable green materials. Precipitation and quantification of lignin from softwood black liquors have been documented and commercialized with well-established methods; however, applying those methods to the precipitation of lignin from hardwood black liquors has produced low lignin yields. A need to understand the main differences between hardwood and softwood lignin precipitation prompted the current investigation. Multiple black liquor samples from sweetgum and pine pulping were obtained at different times of standard kraft cooks. Two lignin fractions were precipitated from each of these black liquors, one at pH 9.5 and one at pH 2.5. Detailed lignin and carbohydrate material balances were performed around each of the sample sets, starting with the wood and ending with precipitated lignin fractions. For all conditions tested, the amount and purity of pine lignin precipitated were superior to sweetgum lignin. The maximum recovery for sweetgum lignin was 69.7%, while for pine lignin, it was 90.9%. [ABSTRACT FROM AUTHOR]

The degree of crystallinity in cellulose significantly affects the physical, mechanical, and chemical properties of cellulosic materials, their processing, and their final application. Measuring the crystalline structures of cellulose is a challenging task due to inadequate consistency among the variety of analytical techniques available and the lack of absolute crystalline and amorphous standards. Our article reviews the primary methods for estimating the crystallinity of cellulose, namely, X-ray diffraction (XRD), nuclear magnetic resonance (NMR), Raman and Fourier-transform infrared (FTIR) spectroscopy, sum-frequency generation vibrational spectroscopy (SFG), as well as differential scanning calorimetry (DSC), and evolving biochemical methods using cellulose binding molecules (CBMs). The techniques are compared to better interrogate not only the requirements of each method, but also their differences, synergies, and limitations. The article highlights fundamental principles to guide the general community to initiate studies of the crystallinity of cellulosic materials. [ABSTRACT FROM AUTHOR]

The importance of teaching, for the development of economies, cultures, and the enrichment of people's lives cannot be overstated. These days biomass and bioenergy teaching has a pivotal role to play in influencing all of the aforementioned areas of life, since fossil fuels are becoming depleted. However, what good is teaching if it cannot be communicated in an intelligible, persuading, and egalitarian manner? A dynamic educational construct between "teacher" and "student" will be the chief mode of promoting knowledge and provoking research for engendering more knowledge. This editorial attempts to show how teaching is a living and symbiotic discipline that we typically take for granted, but once we do it right, we have the power to change the world as we know it. We will briefly explore the example of BioSUCCEED, a platform at NC State University, as a means of communicating knowledge related to biomass and bioenergy. [ABSTRACT FROM AUTHOR]

Flexible-hybrid printed electronics (FHPE) is a rapidly growing discipline that may be described as the precise imprinting of electrically functional traces and components onto a substrate such as paper to create functional electronic devices. The mass production of low-cost devices and components such as environmental sensors, bio-sensors, actuators, lab on chip (LOCs), radio frequency identification (RFID) smart tags, light emitting diodes (LEDs), smart fabrics and labels, wallpaper, solar cells, fuel cells, and batteries are major driving factors for the industry. Using renewable and bio-friendly materials would be advantageous for both manufacturers and consumers with the increased use of (FHPE) electronics in our daily lives. This review article describes recent developments in cellulose and nanocellulose-based materials for FHPE, and the necessary developments required to propagate their use in commercial applications. The aim of these developments is to enable the creation of FHPE devices and components made almost entirely of cellulose materials. [ABSTRACT FROM AUTHOR]

Chitosan (CS) is a material derived from chitin, the most abundant biopolymer on the planet. It has shown potential among a wide variety of biomedical applications especially within the context of self-assembling nanocarriers usable in biomedical applications such as drug delivery, macroscopic injectables, tissue-engineering scaffolds, and nano-imaging agents. To date, many reviews have been focused on the biomedical properties and applications of CS-based nanocarriers, but a review is lacking on the role and prospects of different factors such as formulation parameters and preparation conditions on the properties of amphiphilic chitosan nanocarriers (ACNs) that have shown critical value in advancing drug delivery. [ABSTRACT FROM AUTHOR]

The suitability of specific Sudanese agrowastes, sorghum straw, bagasse, and their 50% blend, were investigated for pulp and papermaking initiatives. A chemical analysis of sorghum straw and bagasse revealed levels of cellulose, lignin, hemicellulose, and ash for sorghum straw and bagasse that signalled a suitable relation to traditional wood feedstocks for pulping and papermaking applications. Moreover, the pulp yield and viscosity of sorghum straw were lower and higher, respectively, compared with the bagasse and the blend. More specifically, the papers obtained from bagasse showed better physical properties (tensile strength, tearing index, bursting index, and folding) compared to those of sorghum straw and the blend. The surface morphologies of the papers were analysed using scanning electron microscopy (SEM), which showed that the fibres had a long, swollen, compact, and closely packed arrangement and were more homogeneous and well-blended for the bagasse compared with the pure sorghum straw and the 50% blend. [ABSTRACT FROM AUTHOR]

Sudan has rich sources of lignocellulose materials from agricultural waste that have potential to be used as a papermaking furnish following adequate chemical compositions, elemental analysis, fibre dimensions, and morphology of millet stalks and date palm leaves. Paper sheet properties from the various pulps made were investigated, and it was found that there was no difference in the polysaccharide (cellulose and hemicelluloses) content between millet stalks and date palm leaves, although millet stalks had a high lignin content of 18.20% relative to date palm leaves' content of 15.34%. Moreover, millet stalks showed a high pulp yield (42.04%) with a viscosity of 665 mL/g compared to that (34.43%, 551 mL/g) and (38.50% and 534 mL/g) of date palm leaves and the blend, respectively. Papers produced from date palm leaves and millet stalk blends showed better physical properties compared to that of pure millet stalks and date palm leaves. The Scanning Electron Microscopy (SEM) analysis showed that fibres in the blend were more closely packed than that of the pure millet stalks and date palm leaves fibers. Based on their physical and chemical composition properties, millet stalks and date palm leaves have a high potential as a furnish for pulp and papermaking. [ABSTRACT FROM AUTHOR]

The cleavage of intermolecular linkages in lignin is a crucial yet complicated factor to properly deconvolute during the pyrolysis of lignin; thus, four typical β-O-4 lignin dimer compounds with different substituents on C α and C β position (including C α O, C α OH and C β CH 2 OH groups) were synthesized. The results showed that a C β CH 2 OH group greatly inhibited the generation of volatile products, and promoted the generation of char. When the C α O group existed alone, the volatility of model compounds reached a maximum of ∼94 mass-%. At low temperatures (<300 °C), the cleavage of intermolecular linkages dominated, followed by secondary pyrolysis of primary products to various gases ( e.g. , CO 2 , CH 4 , CO). Guaiacol and 2-methoxy-benzaldehyde, two typical products, displayed yields that reflected the degree of cleavage of the C β O and C α C β bonds. It was confirmed that oxidation of the C α OH group to C α O facilitated cleavage of the C α C β bond and favored formation of 2-methoxy-benzaldehyde. In addition, new dimers that were intermediates during the pyrolysis process were formed via intermolecular elimination reactions that further affected products distribution and selectivity. [ABSTRACT FROM AUTHOR]

Superabsorbent hydrogels (SAH) are crosslinked three-dimensional networks distinguished by their super capacity to stabilize a large quantity of water without dissolving. Such behavior enables them to engage in various applications. Cellulose and its derived nanocellulose can become SAHs as an appealing, versatile, and sustainable platform because of abundance, biodegradability, and renewability compared to petroleum-based materials. In this review, a synthetic strategy that reflects starting cellulosic resources to their associated synthons, crosslinking types, and synthetic controlling factors was highlighted. Representative examples of cellulose and nanocellulose SAH and an in-depth discussion of structure-absorption relationships were listed. Finally, various applications of cellulose and nanocellulose SAH, challenges and existing problems, and proposed future research pathways were listed. [Display omitted] [ABSTRACT FROM AUTHOR]

Flexible sensors have been widely applied in wearable devices recently. These devices are prone to abrasion, crack, and accidental damage, which result in function failure or even abandonment aggravating environmental degradation. Therefore, it is a huge challenge to endow the flexible sensors with self-healability, recyclability as well as high mechanical property. Herein, a novel recyclable, highly stretchable, self-healing eutectogel was fabricated by freeze-thaw of polyvinyl alcohol (PVA), gelatin and dialdehyde carboxymethyl cellulose (DCMC) in a deep eutectic solvent (DES) with strain rate, humid and temperature sensing capability. The composite eutectogel consisted of imine bond and hydrogen bond reversible networks, which endowed the eutectogel with faster self-healability, as well as the green and simple recyclability. It performed satisfying tensile strength (up to ∼1.25 MPa) with unexceptionable fracture elongation (∼1400%). By leveraging the DES to inhibit freezing and dehydration, the eutectogel was fabricated with a wide working temperature (−20.9 to 64.1 °C) while its weight and sensing performance remained stable after 30 days in open air. The composite eutectogel sensor manifested reliable mechanical and electrical properties under repetitive deformation operation and sensitive responsiveness to real-time variation of rate, temperature, and humidity, which well mimics human breathing in time. Amazingly, based on the hydrolysis of the imine and hydrogen bonds, the recyclable eutectogels retained vast majority of mechanical strength, adhesion, and conductivity. Compared to most synthetic soft materials, the composite eutectogels provide a promising strategy for the development of sustainable multifunctional soft materials that have high environmental adaptability and practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

2,3-Butanediol (2,3-BDO) is an important industrial diol that could function in various fields. Currently, there are many substrates used for 2,3-BDO biosynthesis, but studies using green carbon sources such as corncob hydrolysate as a substrate are lacking. As a widely distributed waste lignocellulose-derived substrate, corncob hydrolysate is nutrient-rich and cost-effective. The present study evaluated 2,3-BDO production via an Enterobacter cholerae strain using corncob hydrolysate as carbon source. Chemical component analysis showed that concentrated corncob hydrolysate contained 233 g/L total sugar and showed no inhibitory effect, but it was beneficial for 2,3-BDO synthesis. Optimization experiments for fermentation resulted in a titer of 47.23 g/L 2,3-BDO with a yield of 0.30 g/g and a productivity rate of 0.66 g/L•h. This study is expected to provide insights for large-scale bioproduction of bulk chemicals utilizing corncob hydrolysates. [ABSTRACT FROM AUTHOR]

A fundamental study was undertaken to determine the general role of heteropolysaccharides during the production of TEMPO-oxidized cellulose nanofibrils (TOCNs). Four major fiber resources, viz. , fully bleached kraft pulps of softwood and hardwood varieties (pine, eucalyptus) and non-woods (bamboo, bagasse) were used because of their substantial morphological differences and relative abundance. The effect of heteropolysaccharides during TEMPO-mediated oxidation and high-pressure homogenization for TOCNs production was investigated under constant conditions. Most galactoglucomannans were removed during oxidation, whereas the majority of xylans were retained. The galactoglucomannans, however, non-beneficially consumed NaClO, the terminal TEMPO oxidant, while xylans adversely affected carboxylate group formation by limiting chemical accessibility to cellulose. However, lower xylans content led to more transparent and processable suspensions, while during mechanical processing, heteropolysaccharides supported nanofibrillation. The average length of the final TOCNs from eucalyptus, bamboo, bagasse, and pine were 290, 350, 360 and 370 nm, respectively, with average widths of ∼4 nm. [ABSTRACT FROM AUTHOR]

Many current and potential uses of cellulosic materials depend critically on the character of their surfaces. This review of the scientific literature considers both well-established and emerging strategies to change the outermost surfaces of cellulosic fibers or films not only in terms of chemical composition, but also in terms of outcomes such as wettability, friction, and adhesion. A key goal of surface modification has been to improve the performance of cellulosic fibers in the manufacture of composites through chemistries such as esterification that are enabled by the high density of hydroxyl groups at typical cellulosic surfaces. A wide variety of grafting methods, some developed recently, can be used with plant-derived fibers. The costs and environmental consequences of such treatments must be carefully weighed against the potential to achieve similar performances by approaches that use more sustainable methods and materials and involve less energy and processing steps. There is potential to change the practical performances of many cellulosic materials by heating, by enzymatic treatments, by use of surface-active agents, or by adsorption of polyelectrolytes. The lignin, hemicelluloses, and extractives naturally present in plant-based materials also can be expected to play critical roles in emerging strategies to modify the surfaces characteristics of cellulosic fibers with a minimum of adverse environmental impacts. [ABSTRACT FROM AUTHOR]

The oxidative degradation of eucalyptus kraft lignin as a function of an oxygen-enriched ionic liquid (IL) medium was investigated as part of a fundamental study to examine its capacity to degrade lignin into a suite of potentially valuable by-products relative to a standard sodium hydroxide solution (control). The variables of temperature, oxygen pressure, reaction time, and catalyst on the aromatic monomer products were controlled, whereas it was found that the yields of various aromatic monomer products were significantly improved when ionic liquid was used as the solvent instead of sodium hydroxide solution. These yields increased more substantially when a mixture of ionic liquid and sodium hydroxide was exploited as the reaction solvent. A quantity of 105.3 mg/g aromatic monomer products can be obtained at a temperature of 150°C, reaction time of two hours, and oxygen pressure of 6 MPa using CuO as the catalyst. In addition to the formation of aromatic monomer products, there were a number of other fascinating functional group and chemical linkage changes observed in the lignin macromolecule within the IL-based reaction system. [ABSTRACT FROM PUBLISHER]

Hemp has become increasingly important as an alternative fiber source for papermaking. However, a substantial knowledge gap for future applications of hemp fibers remains, specifically in pulping as a processing technology. Thus, significant research into optimal pulping methods must be performed to identify processing conditions that produce viable hemp pulps for papermaking applications. The literature has clearly identified the short fiber length of hemp hurd as a major obstacle to effective papermaking as understood from a strength perspective and has been a limitation to any significant work in this arena. To address this issue, genetic improvement efforts were previously undertaken to lengthen the hurd fibers, yet, additional research is needed to understand how to process these new hemp cultivars. Due to their simplicity, soda pretreatment and pulping were chosen as initial processes to investigate. Mild soda pretreatments were investigated as a method to reduce the chip particle size which decreases both liquor penetration distance and pulping time for a subsequent delignification stage. Chip size reduction was observed under multiple experimental conditions however, 12% sodium hydroxide (NaOH) performed the best. Fiber Quality Analyzer (FQA) analyses of soda pulped hemp stalks from improved cultivars resulted in hurd fiber lengths of approximately 1.0–1.2 mm. These fibers are significantly longer than those observed in traditional hurd pulp and comparable to fiber lengths of hardwood pulps. The chemical composition analyses of the raw, pretreated, and pulped hemp reinforced the importance of size reduction pretreatments and treatment severity. At the same processing conditions, larger chips experienced less delignification and xylan removal than smaller chips. Traditional pulping was significantly more effective at delignification than the mild pretreatment and resulted in a hemp sample with three to four times less lignin. The pretreatment and pulping results indicate a promising future direction for hemp in the field of papermaking using genetically improved cultivars. • Soda pretreatment with mechanical action was effective at diminishing chip size. • Pretreatment NaOH concentration had little impact on final chip size distribution. • Pulping of genetically improved hemp furnished fiber lengths similar to hardwoods. • Mild pretreatment was much less effective at removing lignin versus pulping. [ABSTRACT FROM AUTHOR]

Nanofibers were produced by electrospinning aqueous alkaline solutions containing different mass ratios of soy protein and lignin in the presence of poly(ethylene glycol) coadjutant, all of which presented shear thinning behavior. SEM revealed that the addition of polyethylene oxide as a coadjutant indeed facilitated the formation of defect-free fibers whose diameter increased with lignin concentration, in the range between ≈ 124 and ≈ 400 nm. Favorable interactions between lignin and soy protein were identified from data provided by differential scanning calorimetry. In addition, an increased hydrogen bonding and the loss of secondary structure of the proteins as the lignin concentration increased were observed from the disappearance of amide II (∼1500 cm −1 ) and III (∼1400–1200 cm −1 ) bands and a red shift of amide I band in the FT-IR spectrum. The unfolding of the protein contributed to a better interaction with lignin macromolecules, which further improved the electrospinning process. It is concluded that mixtures of lignin and soy proteins, two major renewable resources with interesting chemical features, are suitable for the development of composite sub-micron fibers. [ABSTRACT FROM AUTHOR]

The present work attempts to providedata to warrant the considerationof soy proteins (SP) as potentially useful biomolecules for practicalchemical and surface applications. Despite their sundry properties,SP use has been limited by their high molecular weight. In responseto this limitation, we analyze acid hydrolysates of soy proteins (0.1N HCl, 70 °C) for surface modification. Techniques typical inprotein (SDS-PAGE) as well as colloidal (charge demand and electrophoreticmobility) analyses were used to follow the effects of molecular changesthat occur upon hydrolysis. Adsorption experiments on hydrophobic(polypropylene) and mineral (aluminum oxide) surfaces were subsequentlycarried out to further interrogate the surface activity resultantfrom soy hydrolysis. It was found that during adsorption the hydrolysatestended to form less surface aggregates and adsorbed at faster ratescompared with unmodified SP. Overall, the benefits derived from theapplication of SP hydrolysates are highlighted. [ABSTRACT FROM AUTHOR]

Abstract: A new approach based on microemulsions formulated with at least 85% water and minority components consisting of oil (limonene) and surfactant (anionic and nonionic) is demonstrated for the first time to be effective for flooding wood’s complex capillary structure. The formulation of the microemulsion was based on phase behavior scans of Surfactant–Oil–Water systems (SOWs) and the construction of pseudo-ternary diagrams to localize thermodynamically stable one-phase emulsion systems with different composition, salinity and water-to-oil ratios. Wicking and fluid penetration isotherms followed different kinetic regimes and indicated enhanced performance relative to that of the base fluids (water, oil or surfactant solutions). The key properties of microemulsions to effectively penetrate the solid structure are discussed; microemulsion formulation and resultant viscosity are found to have a determining effect in the extent of fluid uptake. The solubilization of cell wall components is observed after microemulsion impregnation. Thus, the microemulsion can be tuned not only to effectively penetrate the void spaces but also to solubilize hydrophobic and hydrophilic components. The concept proposed in this research is expected to open opportunities in fluid sorption in fiber systems for biomass pretreatment, and delivery of hydrophilic or lipophilic moieties in porous, lignocellulosics. [Copyright &y& Elsevier]