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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]

The review aims at reporting on recent developments in nanocellulose-based materials and their applications in packaging with special focus on oxygen and water vapor barrier characteristics. Nanocellulose materials, including cellulose nanocrystals (CNC), nanofibrillated cellulose (NFC), and bacterial nanocellulose (BNC), have unique properties with the potential to dramatically impact many commercial markets including packaging. In addition to being derived from a renewable resource that is both biodegradable and non-toxic, nanocellulose exhibits extremely high surface area and crystallinity and has tunable surface chemistry. These features give nanocellulose materials great potential to sustainably enhance oxygen and water vapor barrier properties when used as coating, fillers in composites and as self-standing thin films. [ABSTRACT FROM AUTHOR]

Biomaterials and new processes (3D printing and flexible hybrid electronics) offer opportunities to break free from a 2D paper world by allowing for the development of smart multi-dimensional structures. While there has been recent progress reported in each of these areas of technology, to date, the merger of these technologies has been very limited. We believe that their merger offers boundless opportunities and an opportunity for the paper industry to innovate a low cost, sustainable housing solution capable of promoting the well-being of its occupants while minimizing the environmental impact of its daily use. [ABSTRACT FROM AUTHOR]

Molded cellulosic pulp products provide eco-friendly alternatives to various petroleum-based packaging systems. They have a long history of reliable usage for such applications as egg trays and the shipping of fruits. They have recently become increasingly used for the packaging of electronics, wine bottles, and specialty items. Molded pulp products are especially used in applications requiring cushioning ability, as well as when it is important to match the shapes of the packed items. Their main component, cellulosic fibers from virgin or recycled wood fibers, as well as various nonwood fibers, can reduce society's dependence on plastics, including expanded polystyrene. However, the dewatering of molded pulp tends to be slow, and the subsequent evaporation of water is energyintensive. The article reviews strategies to increase production rates and to lower energy consumption. In addition, by applying chemical treatments and processing approaches, there are opportunities to achieve desired end-use properties, such as grease resistance. New manufacturing strategies, including rapid prototyping and advances in tooling, provide opportunities for more efficient form factors and more effective packaging in the future. [ABSTRACT FROM AUTHOR]

Strategic combinations of cellulosic materials with electrically conductive polymers or nanoconductors offer important potential advantages for technological advances, light-weight inexpensive products, applications of novel form factors, and more eco-friendly alternatives to certain forms of smart packaging and electronics. This review of the literature focuses on how such electrically conductive composite systems work, the roles that cellulosic materials can provide in such structures, processes by which electrically-conductive cellulose-based composites and films can be manufactured, and various potential applications that have been demonstrated. Several advantages of cellulose, such as ease of fabrication, compatibility with conductive agents, and sustainability, allow its integration with conductive agents in making conductive composites. Applications of electrically conducting cellulose-based composites for strain sensors, energy storage, solar cells, electrodes, supercapacitors, and smart packaging are discussed. [ABSTRACT FROM AUTHOR]

A comparison among ten market pulps at a laboratory scale using uncreped tissue handsheets was performed to study the performance of wood and non-wood pulps for tissue manufacturing, evaluate what fiber features are desired for a specific tissue property, and determine how non-wood pulps can be used to replace or complement wood pulps in tissue products. A characterization of the fiber morphology and handsheet properties (softness, water absorbency, and strength) was performed at different mechanical refining levels. The results showed that the fiber morphology had a major impact on tissue properties. Market pulps with a combination of long fibers, high coarseness, and low fines content can provide superior bulk and water absorbency. Short fibers with thin cell walls and low fines content can impart superior softness. Bleached bamboo soda pulp can replace hardwood and softwood pulps to provide an excellent combination of water absorbency and strength. Bleached bamboo soda pulp can also replace Northern bleached softwood kraft (NBSK) pulp to impart strength without sacrificing softness. Bleached and semi-bleached wheat straw soda pulps presented a similar combination of softness and strength as Southern bleached hardwood kraft (SBHK) pulp. The wheat straw pulps can be used to replace deinked pulp (DIP) pulp to impart intermediate levels of water absorbency and strength. [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]

Surface treatments of cellulose triacetate (CTA) films via atmospheric pressure plasmas containing helium and either O2 or C3F6 as plasma reactive gas were performed to study their effects on moisture barrier, transmittance, thermal, surface chemistry, and morphological properties. Plasma treated CTA films were characterized using X-ray photoelectron spectroscopy (XPS), attenuated total reflectance-Fourier transform infrared spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy analytical techniques. Both surface chemical and morphological changes were correlated with water vapor transmission rates (WVTRs) and contact angle measurements. XPS spectra showed that the relative chemical composition of the C 1s spectra after O2 plasma treatments exhibits an increase in the relative amount of C--C bonds, which may be due to a change in surface cross-linking. ToF-SIMS spectra showed the depth of treatment of atmospheric plasma treatment of CTA films at about 100 nm. The WVTR of the CTA film was reduced up to 20% after sustainable atmospheric O2/helium plasma, while no significant changes were observed in light transmittance. Thus, the use of sustainable atmospheric plasmas to enhance moisture barrier while maintaining other critical properties such as light transmittance, thermal stability, and morphology of a CTA film could provide significant benefits to the electronics industry. [ABSTRACT FROM AUTHOR]

Optimizing drying energy in the forest products industry is critical for integrating lignocellulosic feedstocks across all manufacturing sectors. Despite substantial efforts to reduce thermal energy consumption during drying, further enhancements are possible. Cellulose, the main component of forest products, is Earth's most abundant biopolymer and a promising renewable feedstock. This study employs all-atom molecular dynamics (MD) simulations to explore the structural dynamics of a small I β -cellulose microcrystallite and surrounding water layers during drying. Molecular and atomistic profiles revealed localized water near the cellulose surface, with water structuring extending beyond 8 Å into the water bulk, influencing solvent-accessible surface area and solvation energy. With increasing temperature, there was a ∼20 % reduction in the cellulose surface available for interaction with water molecules, and a ∼22 % reduction in solvation energy. The number of hydrogen bonds increased with thicker water layers, facilitated by a "bridging" effect. Electrostatic interactions dominated the intermolecular interactions at all temperatures, creating an energetic barrier that hinders water removal, slowing the drying processes. Understanding temperature-dependent cellulose-water interactions at the molecular level will help in designing novel strategies to address drying energy consumption, advancing the adoption of lignocellulosics as viable manufacturing feedstocks. [Display omitted] [ABSTRACT FROM AUTHOR]

The technology of food packaging is responding to significant market dynamics such as the rapid growth in e-commerce and preservation of fresh food, a sector that accounts for over 40% of plastic waste. Further, mandates for sustainability and recent changes in national governmental policies and regulations that include banning single-use plastic products as observed in sweeping reforms in Europe, Asia, and several US States are forcing industries and consumers to find alternative solutions. This review highlights an ongoing shift of barrier coatings from traditional synthetic polymers to sustainable breakthrough materials for paper-based packaging and films. Advantages, challenges and adapting feasibility of these materials are described, highlighting the implications of selecting different materials and processing options. A brief description on progress in methods of coating technologies is also included. Finally, the end fate of the barrier materials is classified depending on the packaging type, coating materials used and sorting facility availability. Different types of coatings, such as water-based biopolymers, due to their greater environmental compatibility, are making inroads into more traditional petroleum-based wax and plastic laminate paperboard products for fresh food bakery, frozen food, and take-out containers applications. In addition, nano-biocomposites have been studied at an accelerating pace for developing active and smart packaging. Based on the momentum of recent developments, a strong pace of continuing developments in the field can be expected. [Display omitted] • Top trends in food packaging are driven by sustainability, e-commerce, and the end fate of the materials. • Recent developments in bio-based materials have the potential of replacing petro-based polymers. • High speed and specialized coating methods have emerged in the past few years for food packaging development. • Businesses are focused on the recycling of synthetic and biopolymers. [ABSTRACT FROM AUTHOR]

Water removal during paper manufacturing is of primary importance to production rate and cost efficiency for the pulp and paper industry. It is crucial to develop methods to reduce energy consumption by increasing the percent solids in the paper web entering the dryers from the presses. This research aimed to develop a fundamental understanding of the effect of bio-chemo-mechanical pretreatments on a bleached softwood fiber matrix and evaluate the impact on the percent solids of the paper web after pressing. Experiments included enzymatic, refining, and cationic polymer pretreatments on the bleached softwood pulps, followed by laboratory papermaking and determining the equilibrium moisture content (EMC) after pressing and the pulp and paper properties. The combined effect of mild refining, controlled enzymatic pretreatments, and cationic strength aids proved to enhance the water removal during wet pressing (up to 35 % reduction) and increase paper strength (up to 60 % increase). The results of increased solids after pressing were used to calculate the potential reduction in drying energy during paper manufacturing. Energy savings of around 10 % for paper drying could be achieved through fiber matrix modification by bio-chemo-mechanical pretreatment. Enzymatic pretreatments have previously been conventionally applied before refining as an energy-saving method. However, this research shows that synergistic actions of enzymes added after refining modify the fibers and create the optimal conditions for enhancement in drainage, press dewatering, and paper properties. [Display omitted] • Enzyme-assisted fiber modifications improve press dewatering and paper strength. • Enzyme blends can enhance fiber cell wall flexibility and fibrillation. • Synergistically, enzymes increased ∼35% press dewatering and ∼60% tensile strength. • Enzymes, mild refining, and cationic biopolymers enhance paper process efficiency. • This research introduces alternative methods for decarbonizing the paper industry. [ABSTRACT FROM AUTHOR]

Climate changes, emerging species of plant pests, and deficits of clean water and arable land have made availability of food to the ever-increasing global population a challenge. Excessive use of synthetic pesticides to meet ever-increasing production needs has resulted in development of resistance in pest populations, as well as significant ecotoxicity, which has directly and indirectly impacted all life-forms on earth. To meet the goal of providing safe, sufficient, and high-quality food globally with minimal environmental impact, one strategy is to focus on targeted delivery of pesticides using eco-friendly and biodegradable carriers that are derived from naturally available materials. Herein, we discuss some of the recent approaches to use biodegradable matrices in crop protection, while exploring their design and efficiency. We summarize by discussing associated challenges with the existing approaches and future trends that can lead the world to more sustainable agricultural practices. Image 1 • Providing food safety and security is critical for the growing global population. • Crop yield is affected by various biotic and abiotic factors. • Targeted/sustained delivery of agrochemicals reduces excessive use of pesticides. • Nature-derived biodegradable materials curtail plant health and environmental harm. • Biodegradable matrices hold promise for sustainable crop protection. [ABSTRACT FROM AUTHOR]

Based on publications related to the use of micro- and nanofibrillated cellulose (MNFC) in papermaking applications, three sets of parameters (intrinsic and extrinsic variables, furnish composition, and degree of dispersion) were proposed. This holistic approach intends to facilitate understanding and manipulation of the main factors describing the colloidal behavior in systems comprising of MNFC, pulp fibers, and additives, which directly impact paper product performance. A preliminary techno-economic assessment showed that cost reductions driven by the addition of MNFC in paper furnishes could be as high as USD 149 per ton of fiber (up to 20% fiber reduction without adverse effects on paper's strength) depending on the cost of papermaking fibers. It was also determined that better performance in terms of strength development associated with a higher degree of MNFC fibrillation offset its high manufacturing cost. However, there is a limit from which additional fibrillation does not seem to contribute to further strength gains that can justify the increasing production cost. Further research is needed regarding raw materials, degree of fibrillation, and combination with polyelectrolytes to further explore the potential of MNFC for the reduction of weight of paper products. [ABSTRACT FROM AUTHOR]

An innovative approach for preparing hemp fibers from hemp hurds for use in tissue and towel grades of paper is described. Hemp hurds are a low value by-product of industrial hemp processing that are generally used for animal bed litter. Tissue paper was fabricated from hemp hurd fibers by following three pulping processes: autohydrolysis (hydrothermal), sodium carbonate-based defibration, and high yield kraft pulping, and benchmarked against hardwood pulp. To meet industrial standards, hardwood and hemp pulp fibers were mixed at a dry mass ratio of 75:25, from which tissue paper sheets were prepared. Desirable tissue paper properties, such as water absorption, burst resistance, softness, and tensile strength (dry and wet), were measured and compared. Characterization of morphological and chemical properties of tissue handsheets was conducted with SEM and time-of-flight-secondary ion mass spectrometry (ToF-SIMS). The combined kraft pulped hardwood and autohydrolyzed hemp pulp fibers displayed improvements in tensile index, burst resistance, and softness of tissue handsheets compared to only kraft hardwood pulp handsheets without adversely impacting water absorption. Hardwood fibers showed a sparse distribution of surface lignin compared to hemp fibers using the same defibration. This technology can lead to a variety of eco-friendly tissue paper products that are not only highly energy efficient, but avoid harsh chemical processing. [ABSTRACT FROM AUTHOR]

New alternatives to plastic straws are being considered due to consumer demands for sustainability and recent changes in government policies and regulations, such as bans on single-use plastic products. There are concerns regarding paper straw quality and stability over time when in contact with beverages. This study evaluated the performance and properties of commercially available paper straws and their counterpart plastic straws in various intended applications. The physical, mechanical, and compositional characteristics, as well as the liquid interaction properties of the straws, were determined. The paper straws were composed mainly of hardwood fibers that were hard sized with a hydrophobic sizing agent to achieve a contact angle of 102° to 125°. The results indicated that all the evaluated paper straws lost 70% to 90% of their compressive strength after being in contact with the liquid for less than 30 min. Furthermore, the paper straws absorbed liquid at approximately 30% of the straw weight after liquid exposure for 30 min. Increased liquid temperatures caused lower compressive strengths and higher liquid uptake in the paper straws. This report provides directions and methods for testing paper straws and defines current property limitations of paper straws relative to plastic straws. [ABSTRACT FROM AUTHOR]

Efficient utilization of forestry, agriculture, and marine resources in various manufacturing sectors requires optimizing fiber transformation, dewatering, and drying energy consumption. These processes play a crucial role in reducing the carbon footprint and boosting sustainability within the circular bioeconomy framework. Despite efforts made in the paper industry to enhance productivity while conserving resources and energy through lower grammage and higher machine speeds, reducing thermal energy consumption during papermaking remains a significant challenge. A key approach to address this challenge lies in increasing dewatering of the fiber web before entering the dryer section of the paper machine. Similarly, the production of high-value-added products derived from alternative lignocellulosic feedstocks, such as nanocellulose and microalgae, requires advanced dewatering techniques for techno-economic viability. This critical and systematic review aims to comprehensively explore the intricate interactions between water and lignocellulosic surfaces, as well as the leading technologies used to enhance dewatering and drying. Recent developments in technologies to reduce water content during papermaking, and advanced dewatering techniques for nanocellulosic and microalgal feedstocks are addressed. Existing research highlights several fundamental and technical challenges spanning from the nano- to macroscopic scales that must be addressed to make lignocellulosics a suitable feedstock option for industry. By identifying alternative strategies to improve water removal, this review intends to accelerate the widespread adoption of lignocellulosics as feasible manufacturing feedstocks. Moreover, this review aims to provide a fundamental understanding of the interactions, associations, and bonding mechanisms between water and cellulose fibers, nanocellulosic materials, and microalgal feedstocks. The findings of this review shed light on critical research directions necessary for advancing the efficient utilization of lignocellulosic resources and accelerating the transition towards sustainable manufacturing practices. [Display omitted] • One key strategic issue facing the forest products industry is the high energy requirements. • The nature of interactions, association, and bonding of lignocelluloses is essential. • Alternative enzymatic treatments targeting the fiber surface can increase dryness while reducing the need for refining. • An understanding of floc formation and micro and nano-fines migration mechanisms is required. • Nanocellulose and microalgal dewatering is critical to enable braoder applicaitons. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Developed Poly(N-Isopropylacrylamide)-Cellulose Nanocrystal hydrogel films. • Achieved unique thermo-responsivity and tunable optical performance. • Developed a hybrid materials system to modulate LCST and moisture content for thermo-responsivity and optical tunability. • Demonstrated a ∼ 15 °C reduction of the LCST relative to pure PNIPAm hydrogel films. • Below the LCST, PNIPAm/CNC hydrogel films exhibit transparency or semi-transparency. Abstract A hybrid materials system to modulate lower critical solution temperature (LCST) and moisture content for thermo-responsivity and optical tunability was strategically developed by incorporating cellulose nanocrystals (CNCs) into a poly(N -isopropylacrylamide) (PNIPAm) hydrogel matrix. The PNIPAm/CNC hydrogel films exhibit tunable optical properties and wavelength bandpass selectivity as characterized by PROBE Spectroscopy and Dynamic Light Scattering (DLS). Importantly, the micro/nano structures of the PNIPAm/CNC hydrogel films were completely different when dried below and above the LCST. Below the LCST, PNIPAm/CNC hydrogel films exhibit transparency or semi-transparency due to the uniform bonding of hydrophilic PNIPAm and CNC through hydrogen bonds. Above the LCST, the hydrogel films engage in both hydrophobic PNIPAm and hydrophilic CNC interactions due to changes in PNIPAm conformation which lead to light scattering effects and hence opacity. Furthermore, the incorporation of CNC induces a ∼ 15 °C reduction of the LCST relative to pure PNIPAm hydrogel films. [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]

Softness, as a subjective perception, is difficult to define and quantify. For decades, panel tests have been used to judge differences in the softness of hygiene tissue samples. Panel tests can be a time-consuming and expensive process. A number of protocols have been developed to quantify the physical properties of tissues associated with softness. The Tissue Softness Analyzer (TSA) by Emtec has gained popularity in characterizing the physical properties of tissues associated with softness. The instrument was designed with softness in mind and attempts to simulate the touch of the human hand. There is currently no comprehensive study that compares the results from a TSA and human panel. In this work, panel tests were used to validate the performance of the TSA with bath tissue. It was determined that one component of the TSA measurements (TS7) linearly correlated with the panel results. Among all of the algorithms available for use with the TSA, the TP2 algorithm most accurately predicted the panel scores. The TSA performed better in predicting the softness of the samples that were dried with a conventional wet press or creped-through air-dryer. [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]

This study aimed to identify the performance properties that drive the shelf price of kitchen paper towels and evaluate whether sustainability is an important driver for pricing. Nineteen products were compared according to their performance (softness, absorbency, and strength), technology, and fiber morphology. Metrics to rank the products in different grades (economy, premium, and ultra) according to their performance were provided. A multiple linear regression showed that absorbency and softness are the most significant properties used to predict the price. Market data indicates that there is a segment of consumers willing to pay a premium price for products marketed as "sustainable", even though their performance is comparatively inferior to the majority of the samples. Sustainable products are up to 85% more expensive than regular products. The metrics obtained in this work can contribute to improvement in market transparency, and aid companies in deciding strategies for product development and new investments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enzymatic hydrolysis is a potential method to upcycle textile wastes. • Mechanical refining promotes high-yield enzymatic hydrolysis of textiles. • Dyes inhibit the enzymatic hydrolysis of textile wastes. • Chlorine-free oxidation removes dyes and whitens textiles with low chemical dosage. • Mechanical refining + oxidation processes boost enzyme conversion of dyed textiles. Given the increasing concern over textile waste management and the proliferation of textile landfills, enzymatic hydrolysis of cotton represents a potential pathway to upcycle textile waste into valuable chemical building blocks. However, this pathway is challenged by the presence of persistent dyes, hindering enzyme performance. To overcome this issue, environmentally friendly and total chlorine free oxidation methods such as ozone and alkaline hydrogen peroxide were used in combination with mechanical refining pretreatment. The results showed that the enzymatic conversion of black-dyed cotton, without oxidation, resulted in a glucose yield of only 60% as compared to 95% for undyed cotton fibers. On the other hand, the inclusion of oxidation processes in the pretreatment stage resulted in a glucose yield of 90% via enzymatic hydrolysis at expense of using low oxidation chemicals and low enzyme charges. This work highlights the potential of oxidation methods, enzymatic hydrolysis, and mechanical refining as an ecofriendly pathway for generating value-added chemicals from cotton textile waste while promoting economic circularity. [ABSTRACT FROM AUTHOR]

Commercialization of cellulose nanocrystals ( CNC) presents opportunities for a wide range of new products. Techno-economic assessments can provide insightful information for the efficient design of conversion processes, drive cost-saving efforts, and reduce financial risks. In this study, we conducted techno-economic assessments for CNC production using information from the USDA Forest Products Laboratory Pilot Plant, literature, and discussions with experts. Scenarios considered included variations related to greenfield, co-location, and acid recovery. Operating costs, capital investment, minimum product selling price ( MPSP), financial performance metrics, and the effect of drying and higher reaction yields on CNC manufacturing financials were estimated for each scenario. The lowest MPSP was found for the co-location without acid recovery scenario, mainly driven by capital investment. Risk analysis indicates 95% probability of manufacturing costs lower than USD 5900/t of CNC (dry equivalent) and a MPSP lower than USD 7200/t of CNC (dry equivalent). Finally, based on our analysis, we provide guidance on process optimizations that can improve the economic performance of CNC manufacturing process. In addition, a risk profile of the CNC manufacturing business is provided. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

This review article was prompted by a remarkable growth in the number of scientific publications dealing with the use of nanocellulose (especially nanofibrillated cellulose (NFC), cellulose nanocrystals (CNC), and bacterial cellulose (BC)) to enhance the barrier properties and other performance attributes of new generations of packaging products. Recent research has confirmed and extended what is known about oxygen barrier and water vapor transmission performance, strength properties, and the susceptibility of nanocellulose-based films and coatings to the presence of humidity or moisture. Recent research also points to various promising strategies to prepare ecologically-friendly packaging materials, taking advantage of nanocellulose-based layers, to compete in an arena that has long been dominated by synthetic plastics. Some promising approaches entail usage of multiple layers of different materials or additives such as waxes, high-aspect ratio nano-clays, and surface-active compounds in addition to the nanocellulose material. While various high-end applications may be achieved by chemical derivatization or grafting of the nanocellulose, the current trends in research suggest that high-volume implementation will likely incorporate water-based formulations, which may include water-based dispersions or emulsions, depending on the enduses. [ABSTRACT FROM AUTHOR]

Cellulosic fiber collapse is a phenomenon of fundamental importance for many technologies that include tissue/hygiene to packaging because it governs their essential materials properties such as tensile strength, softness, and water absorption; therefore, we elaborate cellulose fiber collapse from water interactions. This is the first attempt to directly correlate fiber collapse and entrapped or hard-to-remove (HR) water content through DSC, TGA and SEM. Freeze-drying and oven drying were individually investigated for influence on collapse. SEM of the fibers at different moisture contents show that irreversible collapsing begins as entrapped water departs the fiber surface. The removal of HR water pulls cell walls closer due to strong capillary action which overwhelms the elastic force of the fiber lumen which results in partially or fully irreversible collapse. The initial moisture content and refining intensity were found to regulate HR water content and consequently played a vital role in fiber collapsing. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Extraction of lignin-containing cellulose nanofibers (LCNF) from hemp hurds waste. • Development of LCNF coatings/films with reduced polarity and low hydrophilicity. • Elucidation of the role of lignin content and distribution on barrier properties. • Significantly higher water contact angle with LCNF coatings and films. • LCNF-based coatings/films can contribute to a circular economy and sustainability. Residual hemp (Cannabis sativa) hurd fibers obtained from hydrothermal, carbonate, and kraft treatments were the resources used to obtain lignocellulosic nanofibers (LCNF) by using an ultra-fine friction grinder. The morphological, crystallinity, and chemical characteristics of the nanocellulose films were carried out using SEM, XRD, EDX and ToF-SIMS. Water barrier properties of the same were measured in terms of water contact angle, water vapor permeability (WVP) and water absorption. The barrier properties were found to be dependent not only on the lignin content and lignin distribution, but also on the film density and porous structure. LCNF films and coatings showed much higher water contact angle (WCA) (80°-102°) than films produced from the bleached CNF. WVP was found to be more dependent on the density of films than lignin content. Overall, LCNF-based films and coatings derived from hemp hurd residual fibers can contribute to a circular economy and sustainability. [ABSTRACT FROM AUTHOR]

Transparent and High Barrier Plasma Functionalized Acrylic Coated Cellulose Triacetate Films. • Fabrication of transparent and high barrier coated cellulose triacetate (CTA) films. • Enhanced adhesion and curing of acrylic coatings via atmospheric plasma treatments. • Significant reduction in WVTR while maintaining excellent transparency. • Modulation of surface texture via plasma compositions and crosslinking agents. Transparent and high moisture barrier acrylic coatings were obtained by deposition of acrylic resin containing crosslinking agents onto cellulose ester films, followed by exposure to atmospheric plasma. The effects of monomers, crosslinking agents, and polymerization methods were studied. The surface chemical composition, morphology, water vapor transmission rate (WVTR), light transmittance, and adhesion performance of the coated cellulose triacetate (CTA) films were characterized for the acrylic coated films and for different plasma treatments. Coated films showed a significant reduction in water vapor permeability while maintaining excellent transparency when compared with uncoated films. Furthermore, adhesion of the coating to the CTA film was also improved due to plasma treatment. It was also found that plasma curing on the coated oligomers can induce morphological changes and significantly increase surface roughness and hydrophilicity. The roughness texture observed via SEM analysis indicated that the types of plasma polymerization and the amount of crosslinking agents control the texture types for acrylic coating. Plasma-assisted acrylic coated CTA films can be used in electronic displays, medical, and packaging applications. [ABSTRACT FROM AUTHOR]

• Tunable poly(N-Isopropylacrylamide)-cellulose nanofibrils hydrogel films. • Fabrication using inverted SLA 3D printing to provide a new manufacturing platform. • Switchable bio-adhesion to bacteria depending on the CNF content and distribution. • Unique thermo-responsivity and tunable optical performance. • Modulation of LCST (∼ 8 °C reduction) relative to pure PNIPAm hydrogel films. A hybrid poly(N-isopropylacrylamide) (PNIPAm)/cellulose nanofibrils (CNFs) hydrogel composite was fabricated by inverted stereolithography 3D printing to provide a new platform for regulating lower critical solution temperature (LCST) properties and thus tuning optical and bioadhesive properties. The phenomena of interest in the as-printed PNIPAm/CNF hydrogels may be attributed to the fiber-reinforced composite system between crosslinked PNIPAm and CNFs. The optical tunability was found to be correlated to the micro/nano structures of the PNIPAm/CNF hydrogel films. It was found that PNIPAm/CNF hydrogels exhibit switchable bioadhesivity to bacteria in response to CNF distribution in the hydrogels. After 2.0 wt% CNF was incorporated, it was found that a remarkable 8°C reduction of the LCST was achieved relative to PNIPAm hydrogel crosslinked by TEGDMA without CNF. The prepared PNIPAm/CNF hydrogels possessed highly reversible optical, bioadhesion, and thermal performance, making them suitable to be used as durable temperature-sensitive sensors and functional biomedical devices. [ABSTRACT FROM AUTHOR]

• CNF/MWCNTs films with a structure of semi-interpenetrating networks were fabricated. • Percolation threshold level of CNF/MWCNTs membranes of 1.88 wt% was achieved. • CNF/MWCNTs films with 10 wt% MWCNTs showed a high conductivity value of 37.6 S/m. • Resistances of CNF/MWCNTs films were affected by bending states to a minor extent. • Capacitance of the pressure sensors was almost linearly dependent on pressure. Highly conductive multi-walled carbon nanotubes (MWCNTs) and flexible cellulose nanofibers (CNF) membranes with semi-interpenetrating networks structure were fabricated using the typical paper-making method, which was simple and cost-effective. The Scanning electron microscope (SEM), Fourier-transform infrared (FT-IR), and thermal gravimetric analysis (TGA) were used to estimate the morphology, chemical structure, and thermal stability of the membranes. The mechanical, optical, and electrical properties of the membranes were characterized with a uniaxial tensile testing machine, ultraviolet visible spectroscope, and digital multimeter, respectively. The results indicated that the membranes containing 10 wt% of MWCNTs showed a high conductivity value of 37.6 S/m, and the sheet resistances of the membranes were stable at different bending states. Furthermore, we demonstrated the electrical features of membrane-based capacitive pressure sensors based on CNF/MWCNTs. The proposed method for fabricating CNF/MWCNTs membranes can simplify the production process and have great practical potential in various electronics applications such as touch screens. [ABSTRACT FROM AUTHOR]

The cover image, by Camilla Abbati de Assis et al., is based on the Modeling and Analysis Conversion Economics of Forest Biomaterials: Risk and Financial Analysis of CNC Manufacturing, DOI: . [ABSTRACT FROM AUTHOR]