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Family groups in the ancient cultures of China, Korea, and Japan have toiled for generations in an effort to out-compete their neighbors in the pursuit of handmade paper products having better strength performance, in addition to flatness, uniform appearance, and other desirable attributes. Study of the history of the papermaking craft reveals a remarkable ability of ancient peoples to discover advantageous ways to prepare the cellulosic pulp, to improve its brightness, and to form uniform and strong paper sheets. But though the ancients knew how to “beat” the pulp to improve its bonding ability, there is no evidence of any of them having attempted to greatly “over-beat” some of the fiber, thus making nanocellulose, for potential addition to the fiber mixture. Why not? In this editorial, it is proposed that the ancients may have discovered that adding very highly fibrillated cellulose material to paper was not a good idea.

Factors affecting the swelling of cellulosic fibers are considered in this review. Emphasis is placed on aqueous systems and papermaking fibers, but the review also considers cellulose solvent systems, nanocellulose research, and the behavior of cellulosic hydrogels. The topic of swelling of cellulosic fibers ranges from effects of humid air, continuing through water immersion, and extends to hydrogels and the dissolution of cellulose, as well as some of its derivatives. The degree of swelling of cellulose fibers can be understood as involving a balance between forces of expansion (especially osmotic pressure) vs. various restraining forces, some of which involve the detailed structure of layers within the fibril structure of the fibers. The review also considers hornification and its effects related to swelling. The expansive forces are highly dependent on ionizable groups, pH, and the ionic strength of solution. The restraining forces depend on the nature of lignin, cellulose, and their detailed structural arrangements.

This editorial considers three groups of individuals and how they often find themselves following common ways of thinking. Artists, especially those who become well known, are hard workers and somewhat stubborn. Once they have found a type of paper that works well for them, they tend to develop loyalty to it, regardless of what the label on the ream wrap may say. Papermakers, ancient and modern, likewise have tended to stick with practices that are convenient to them at the moment, whether or not they contribute to archival quality. Fortunately, the transition to alkaline papermaking practices means that modern printing papers tend to last a lot longer. Increasing knowledge of the importance of acid-free paper, as well as the principles of sustainability, are making positive contributions to our ongoing cultural heritage, at least to the part of that heritage that is related to cellulosic materials.

Size presses on paper machines are used to apply a solution of a polymer – usually starch – to the surface of the sheet and thereby to increase the stiffness, surface strength, and printing quality of the product. This article reviews publications dealing with the size press equipment, the materials, and factors affecting both the operating efficiency and attributes of the resulting paper. The emergence of film-press equipment (e.g. blade-metering size presses) in the 1980s has greatly decreased the frequency of web breaks and increased productivity. Starch technology at the size press, though relatively mature, continues to evolve. By adjustment of starch attributes, solids levels, and incorporating other additives, modern papermakers can tune size press outcomes to meet a range of paper product requirements, including strength, hydrophobicity, and the reduction of air permeability. By application of various synthetic polymers, mineral particles, and even nanocellulose in combination with starch or other base polymers, there is potential to extend the technology to meet a range of future needs for paper products.

Terminology plays a crucial role in shaping our understanding of a field. In this editorial, we focus on the widely used terms "wet end" and "wet end chemistry" within the realm of papermaking. By delving into historical records, our aim is to provide a deeper understanding and a clearer perspective on these terms. It is worth noting that exploring terminology can enhance comprehension and foster a more comprehensive understanding of the subject matter.

Picking up a discarded can or bottle and placing it in a recycling bin may seem like a very small step to take in the direction of making a better world. The scope of benefits that might accrue, by combining many such steps, and making careful plans, was highlighted in a recent Waste to Advanced Resources Matter (WARM) workshop hosted at this university. As shown during the discussions at the workshop, those who are deeply involved with issues of waste management, climate change issues, and care for our planet already know the “broad brush” answers regarding what needs to be done. Now is the time for action in implementing efficient and widespread recovery of valuable materials and energy from what we presently throw away.

This editorial considers hindrances that keep me from making sure that my used wooden furniture items don’t get thrown out at a point where their wooden content still has decades or hundreds of years of potential service left in them. I am a careless and lazy person, and I am not always appreciating the different ways in which other people might be ready to appreciate and utilize my cast-off items. Continued usage of a wooden item can be the ultimate in minimizing environmental impacts. I might envision that the only usage of an old, scuffed wooden dining room set is full restoration. But my niece might need it for her college apartment. A friend of a friend might need it for an informal basement art studio. Alternatively, if the set is really well beyond use in its original form, it could be converted into wood particles for particleboard or incinerated to generate renewable energy. Whether I use eBay, word of mouth, my church’s electronic bulletin board, or just put the item out by the curb on a sunny day, a wooden item of furniture has the potential to continue to provide valuable service for much longer than I might first imagine.

For about two millennia, paper has served as a main medium for preservation of people’s ideas, stories, contracts, and art. This article reviews what is known about the various components that make up paper from the perspective of their long-term stability under typical storage conditions. Literature evidence is considered relative to the susceptibility of different paper components to embrittlement, acid hydrolysis, microbiological attack, and discoloration, among others. The cellulose that makes up a majority of most paper items is demonstrably stable enough to persist for many hundreds of years on the shelves of archival collections, though it is susceptible to acid-catalyzed hydrolysis, which can be accelerated by byproducts of decomposition. Though less attention has been paid to the archival performance of various minor components of modern paper products, evidence suggests that at least some of them are subject to likely breakdown, embrittlement, or decay in the course of prolonged storage. Based on these considerations, one can envision different categories of paper that can be expected to meet different levels of storage stability: ancient recipes for handmade papermaking, e.g. washi and hanji, archival-grade paper products, ordinary modern alkaline paper products, and paper manufactured without concerns for its longevity.

Fire hazard is a constant risk in everyday life with the use of combustibles such as polymeric materials, wood, and fabrics, to name a few. Halogenated compounds have been widely used as efficient flame-retardants, often being applied as coatings or impregnations. With growing environmental concerns and regional bans on the use of halogenated flame-retardant compounds, bio-based alternatives are garnering significant research interest. Naturally occurring materials such as eggshells, DNA, and certain proteins have developed a self-defense mechanism against fire over millions of years of evolution. Cork, a naturally occurring biological tissue in outer bark, is of interest as it is often used as a heat shield and moisture repellent, specifically in spacecraft. A deeper look into the chemical structure of cork indicates the presence of suberin, a bio-polyester group that makes up as much as 40% of its chemical composition. These bio-polyester groups play a key role as a protective barrier between the plant and the surrounding external environment. Thus, the role of suberin in plants could be mimicked for the design of biobased flame-retardant materials.

This review article considers processes by which the main components of wood have been reported to arrange themselves into various kinds of organized structures, at least to a partial extent. The biosynthesis of wood provides the clearest examples of such self-organization. For example, even before a cellulose macromolecule has been completely synthesized in a plant organism, the leading parts of the polymer chains already will have assembled themselves into organized crystals, i.e., nano-fibrils. This review then considers a challenge that faces industrial engineers: how to emulate the great success of natural systems when attempting to achieve favorable materials properties, process efficiency, and environmental friendliness when developing new engineered wood structures, barrier films, and other desired products composed of lignocellulosic materials. Based on the reviewed literature, it appears that the main chemical components of wood, even after they have been isolated from each other, still have a remnant of their initial tendencies to come back together in a somewhat non-random fashion, following mechanisms that can be favorable for the production of engineered materials having potentially useful functions.

In many of its current and potential applications, technologists treat the surface of cellulose to render it more hydrophobic. By use of a variety of hydrophobic sizing treatment strategies, the bulk cellulose phase becomes covered up with a layer having lower polarity and less inclination to interact with water. Often, the goal is to use a relatively low amount of additive to cover up or change just the surface of the cellulosic material, while still benefiting from the strength, recyclability, relatively low cost, and other favorable features of the bio-based material. But what often gets forgotten is that the hydrophilic nature of pure cellulose is not very high, and there are ways to manipulate such characteristics without reacting the material or covering it up. Sometimes reacting the cellulose with hydrophobic substituent groups appears to make it more water-loving. So, when thinking broadly of processing options for new applications, there are several contrasting approaches to consider.

The release of soils and impurities from cellulosic surfaces plays a critical role in such processes as the laundering of clothes and the deinking of wastepaper pulps. This article reviews publications that provide evidence about factors that affect such release and the mechanisms by which such factors operate. In general, cellulosic substrates provide advantages for the release of contaminants due to their hydrophilic nature and due to their permeability, allowing the transport of surfactants to contact interfaces with dirt. However, the same permeability of cellulosic material also provides opportunities for contaminants to work themselves into internal crevices and pores, from which they are difficult to remove. The article also reviews aspects of theory related to detergency and how those theories relate to the laundering, deinking, and purifying of substrates based on cellulose and related plant materials. Cellulose and some of its derivatives also can play a role in detergent formulation, especially as builders or as finishes placed on textile surfaces, which sometimes aid in the release of dirt.

This editorial considers the use of images as a way to enhance the readability and possibly the impact of scientific writing. Readers are asked to envision effective scientific writing as a form of storytelling. Some stories can be enhanced by adding a diagram or a step-by-step procedure. Inherently dull results might be enlivened (in a cautious manner) with a non-typical graphical portrayal. A potentially tedious theoretical point might be lightened with a touch of humor, which might seem out of place if it were expressed in text. Keep these options in mind as you are creating your next story, i.e., your next research article.

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 energy-intensive. 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.

Paper, nanocellulose, and other polysaccharide-based materials can be excellent candidates for food packaging barrier layers, except that they tend to be vulnerable to moisture. This article reviews published research describing various chemical treatments having the potential to render hydrophobic character to such layers. Emphasis is placed on systems in which hydrophobic monomers are used to treat either particles or sheets comprised largely of polysaccharides. A goal of this review is to identify combinations of materials and procedures having promise for scale-up to industrial production, while providing effective resistance to moisture. The idea is to protect the underlying polysaccharide-based barrier layers such that they can continue to impede the transfer of such permeants as oxygen, greases, flavor compounds, and water vapor. A further goal is to minimize any adverse environmental impacts associated with the treatments. Based on the research articles considered in this review, promising hydrophobic treatments can be achieved involving silanes, ester formation, other covalent interactions, plasma treatments, and to some extent by various treatments that do not require formation of covalent bonds. The article is designed such that readers can skip ahead to items of particular interest to them.