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The conformation of a polyelectrolyte (PE) brush grafted to the inner surface of a long cylindrical mesopore was described within analytical Poisson–Boltzmann strong stretching approximation. The internal structure of the PE brush, including brush thickness and radial density profile of monomer units, and radial distribution of electrostatic potential were analyzed as functions of the pore radius, degree of polymerization, and grafting density of the brush-forming PE chains as well as ionic strength of the solution. It is demonstrated that narrowing of the pore leads to a non-monotonous variation of the brush thickness, which passes through a maximum when the brush thickness becomes equal to the pore radius. Variation in the salt concentration triggers conformational transition that leads to the opening or closing of the hollow (PE-free) channel in the pore center that potentially allows controlling of the pore-selective permeability for charged nanocolloidal particles (e.g., globular proteins or viruses). The predictions of the analytical theory were validated by numerical calculations using the Scheutjens–Fleer self-consistent field modeling method. These theoretical findings may be used for the design of highly selective smart mesoporous membranes with PE brush-functionalized pores for, e.g., protein separation and purification. [ABSTRACT FROM AUTHOR]

We present the explicit bonding Reaction ensemble Monte Carlo (eb-RxMC) method, designed to sample reversible bonding reactions in macromolecular systems in thermodynamic equilibrium. Our eb-RxMC method is based on the reaction ensemble method; however, its implementation differs from the latter by the representation of the reaction. In the eb-RxMC implementation, we are adding or deleting bonds between existing particles, instead of inserting or deleting particles with different chemical identities. This new implementation makes the eb-RxMC method suitable for simulating the formation of reversible linkages between macromolecules, which would not be feasible with the original implementation. To enable coupling of our eb-RxMC algorithm with molecular dynamics algorithm for the sampling of the configuration space, we biased the sampling of reactions only within a certain inclusion radius. We validated our algorithm using a set of ideally behaving systems undergoing dimerization and polycondensation reactions, for which analytical results are available. For dimerization reactions with various equilibrium constants and initial compositions, the degree of conversion measured in our simulations perfectly matched the reference values given by the analytical equations. We also showed that this agreement is not affected by the arbitrary choice of the inclusion radius or the stiffness of the harmonic bond potential. Next, we showed that our simulations can correctly match the analytical results for the distribution of the degree of polymerization and end-to-end distance of ideal chains in polycondensation reactions. Altogether, we demonstrated that our eb-RxMC simulations correctly sample both reaction and configuration spaces of these reference systems, opening the door to future simulations of more complex interacting macromolecular systems. [ABSTRACT FROM AUTHOR]

Mixing Gibbs energy and phase equilibria of aqueous solutions of polyglycine were studied theoretically by means of polymer reference interaction site model integral equation theory combined with the Gibbs–Duhem method. In addition to the ordinary liquid–liquid phase separation between dilute and concentrated solutions, the theoretical calculation predicted the coexistence of two coacervate phases, namely, the lower- and higher-density coacervates. The relative thermodynamic stabilities of these two phases change with the polymerization degree of polyglycine. The higher-density coacervate phase was rapidly stabilized by increasing the polymer length, and the lower-density phase became metastable at large polymers. The hydrogen bonds between the peptide chains were strengthened, and water was thermodynamically destabilized in the higher-density coacervate. A possible relation with the formation of amyloid fibril within a liquid droplet is also discussed. [ABSTRACT FROM AUTHOR]

Hard carbon materials are considered as one of the most commercially promising anode materials for sodium-ion batteries because of their abundant resources, cost-effectiveness and stable cycling performance. However, to rationally regulate the graphitic microcrystalline and pore structure of hard carbon toward advanced sodium storage performance remains a daunting challenge. Here, a simple molecular engineering strategy is developed to synthesize hard carbon featuring diverse graphitic microstructures and pore structures by modulating the polymerization degree of cellulose through pretreatment. Remarkably, cellulose with an appropriate degree of polymerization is cross-linked during the pyrolysis process, forming large layer spacings and multi-layer short graphite microcrystalline structures, resulting in the formation of a rich closed-pore structure. As a consequence, the optimized hard carbon delivers a reversible capacity of 344.5 mA h g−1 at 0.05 A g−1 and a superior rate performance of 251.2 mA h g−1 at 2 A g−1. Moreover, it demonstrates a plateau capacity retention rate of 85.2% under high current density conditions. Additionally, dynamic analysis and in situ X-ray diffraction (XRD) elucidate the electrochemical advantages and sodium storage mechanisms. This study fundamentally sheds light on the molecular design of cellulose-based hard carbon materials thereby showcasing their substantial potential for application in cost-effective and environmentally friendly energy storage devices. [ABSTRACT FROM AUTHOR]

Glucan oligomer is a unique glucose-derived component with versatile applications as a plant growth elicitor and prebiotic based on its degree of polymerization (DP) and glycosidic bond species. However, in conversional aqueous media, glycosylation can be carried out among 5 free –OH groups on glucose, resulting in a glucan oligomer linked through various uncontrolled glycosidic bonds, which can lead to uncertainty of their application. To address this challenge, the confined synthesis of the glucan oligomer in the micropores of zeolites was developed. Glucose was impregnated into the microporous channel of H-Y with the FAU framework or H-MOR with the MOR framework to restrict its spatial configuration and thereby selectively produce the glucan oligomer with specific glycosidic bonds. The results showed that a 41.7% yield of the glucan oligomer with the DP ranging from 2 to 5 can be produced in H-Y, and 59.2% of the formed glucan oligomer was linked through (1 → 6) glycosidic bonds. When H-MOR was used as a catalyst, a high glucan oligomer yield of 61.7% was achieved with glucose units linked through 87.6% of (1 → 4) linkages. The one-dimensional microporous structure of MOR zeolites is not only beneficial for controlling the glycosidic bond structure, but can also improve the diffusion of the produced glucan oligomer, resulting in facile separation of the glucan oligomer from the zeolites. The H-Y and H-MOR used in glycosylation can be readily regenerated via calcination in air after removing the organic residues, and the catalysts can be recycled more than 5 times without catalytic performance decline. [ABSTRACT FROM AUTHOR]

This study explored the effect of CaO/Al2O3 ratio on the fluidity and structure of CaO–Al2O3–MgO–V2O3 slag used for smelting Al–V alloys. With increasing CaO/Al2O3 ratio, viscosity progressively decreased, while the free running temperature initially decreased and then increased, with a turning point at a ratio of 0.8. Introducing CaO disrupted the bridging oxygen by releasing free oxygen, leading to the formation of non-bridging oxygen. Consequently, bridging oxygen decreased while non-bridging oxygen and free oxygen increased with higher CaO/Al2O3 ratio, as demonstrated by XPS analysis. 27Al MAS-NMR spectra revealed that AlO4 tetrahedra consisting of Q2(Al), Q3(Al), and Q4(Al) units dominated the slag, accounting for more than 90 mol pct of the Al3+ species, with smaller amounts of AlO5 and AlO6 units. As the CaO/Al2O3 ratio increased, Q4(Al) and Q3(Al) units with highly coordinated bridging oxygens were continuously converted to Q2(Al) units, resulting in a lower degree of polymerization within the aluminate network. [ABSTRACT FROM AUTHOR]

The viscous behavior and microstructure of CaF2–CaO–Al2O3–MgO slag with different B2O3 contents for electroslag remelting were investigated by employing the rotating cylinder method and molecular dynamics (MD) in conjunction with the Raman spectroscopy measurement. The results show that the viscosity of B2O3-containing ESR slag at 1823 K increased from 0.008 to 0.026 Pa s, the turning point temperature decreased from 1610 K to 1583 K, and the viscous flow activation energy of the slag decreased from 197.33 to 73.31 kJ mol−1, when the increase of B2O3 content from 2 to 7mass pct. Increasing B2O3 promotes the formation of [BO3]3− structures and [AlO3F]4− structure unit and increases the degree of polymerization of the slag. It is preliminarily speculated that increasing B2O3 destroys [AlO4]5−–[AlO4]5− structure to form [BO3]3−–[AlO4]5− structure (or [BO4]5−–[AlO4]5−). Consistent with the results of molecular dynamics calculations, the Raman spectroscopy results also show that the aluminate structure network of ESR slag is depolymerized and more borate structures units are generated as B2O3 content increases. Therefore, B2O3 can complicate the melt structure and increase the viscosity of ESR slag. [ABSTRACT FROM AUTHOR]

Molecular simulations offer valuable insights into thermosetting polymers' microstructures and interactions with small molecules, aiding in the development of advanced materials. In this study, we design two cyanate resin models featuring monomers of different sizes and employ a previously developed method to generate crosslinked structures. We then analyze their crosslinking processes and physicochemical properties. Using quantum chemistry calculations and a GCMC/MD approach, we investigate CO2 adsorption. Our results show that monomer size does not significantly affect the crosslinking process and provides a degree of polymerization as 83.8 ± 0.3% vs. 76.7 ± 1.4%, but it does influence key properties, such as the glass transition temperature (520 K vs. 420 K) and Young's modulus (2.32 GPa vs. 1.77 GPa). Moreover, CO2 adsorption differs between the two models: the introduction of propyl ether moieties lowers by around 70% CO2 uptake, indicating that specific adsorption sites impact gas adsorption. This study demonstrates a promising strategy for designing and optimizing thermosetting polymers with controllable gas separation and storage capabilities. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rice bran, a by‐product of rice processing, has not been fully utilized except for the small amount used for raising animals. The raw material source requirements of microcrystalline cellulose are becoming increasingly extensive. However, the characteristics of preparing microcrystalline cellulose from rice bran have not been reported, which limits the application of rice bran. RESULTS: Microcrystalline cellulose was obtained from rice bran by alkali treatment, delignification, bleaching and acid hydrolysis. The morphology, particle size distribution, degree of polymerization, crystallinity, and thermal stability of rice bran microcrystalline cellulose were analyzed. The chemical compositions, scanning electron microscopy and Fourier‐transform infrared analysis for rice bran microcrystalline cellulose showed that the lignin and hemicellulose were successfully removed from the rice bran fiber matrix. The morphology of rice bran microcrystalline cellulose was shown to be of a short rod‐shaped porous structure with an average diameter of 65.3 μm. The polymerization degree of rice bran microcrystalline cellulose was 150. The X‐ray diffraction pattern of rice bran microcrystalline cellulose showed the characteristic peak of natural cellulose (type I), and its crystallization index was 71%. The rice bran microcrystalline cellulose may be used in biological composites with temperatures between 150 °C and 250 °C. CONCLUSION: These results suggest the feasibility of using rice bran as a low‐price source of microcrystalline cellulose. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Oil‐in‐oil nonaqueous emulsions are of great interest for developing emulsion‐templated polymers and encapsulation systems that are incompatible with water‐sensitive substances. Tailor‐made amphiphilic block copolymers are by far the most efficient stabilizers for oil‐in‐oil emulsions while less attention is given to copolymers with more complex architectures. Here, we report the stabilization of DMSO‐silicone oil interface by bottlebrush random copolymers (BRCPs) containing norbornene backbones with densely grafted poly(methyl methacrylate) (PMMA) and polystyrene (PS) side chains. The assembly kinetics of BRCPs at the DMSO‐silicone oil interface can be divided into three processes, including diffusion, reconfiguration and reorganization, and can be varied by tuning the degree of polymerization of the backbone (NB). Due to the high efficiency of BRCPs in reducing the interfacial tension, when using BRCPs as stabilizers, stable silicone oil‐in‐DMSO traditional emulsions and high internal phase emulsions (HIPEs) can be successfully obtained, while no stable emulsions can be achieved with linear PMMA‐b‐PS serving as the stabilizer. This study, for the first time, underscores the great potential of amphiphilic bottlebrush copolymers in preparing oil‐in‐oil emulsions. Given the advances in polymerization strategy, a broad variety of amphiphilic bottlebrush copolymers are expected to be synthesized and applied in the stabilization of nonaqueous biphasic systems. [ABSTRACT FROM AUTHOR]

We report a simple procedure to produce carboxylated cellulose nanocrystals (CNCs) from grassy biomass (Miscanthus X Giganteus) using a two-step approach consisting of biomass fractionation with a protic ionic liquid followed by oxidation of the resulting cellulose-rich pulps with H2O2. The impact of the fractionation severity on the composition, structure, size, thermal stability, crystallinity, and degree of polymerization of the CNCs was evaluated. It was found that fractionation severity had a large impact on the pulp purity and its reactivity during the oxidation stage. Nevertheless, the impact on the properties of the final CNCs was small. CNCs were recovered as suspensions of negatively charged, electrostatically stable, needle-like CNCs with a lower degree of crystallinity (58–61%) compared to the precursor pulps (65–69%). The presence of carboxyl groups on the surface of the CNCs facilitated the stability of the suspensions but also caused a slight decrease in the thermal stability of the CNCs. A milder oxidation process followed by ultrasonication allowed us to maximize the production of CNCs while better preserving the degree of crystallinity of the cellulose (63%). [ABSTRACT FROM AUTHOR]

Periodically disordered regions can be induced by drying in cellulose microfibrils of several plant species. In this study, cellulose nanocrystals were prepared from never-dried and oven-dried cellulose samples from Egeria densa by sulfuric acid hydrolysis and observed with transmission electron microscopy. Cellulose nanocrystals from never-dried samples were long (> 1 μm in length), curved smoothly, and had very few kinks. In contrast, cellulose nanocrystals from oven-dried samples were shorter (50–600 nm in length) and were almost entirely straight. These results indicated that never-dried cellulose microfibrils lacked the disordered regions along the microfibril and exhibited a continuous, low bending rigidity. Never-dried and oven-dried cellulose samples from E. densa were subjected to acid hydrolysis, dissolution in 1% LiCl/dimethylacetamide, and size-exclusion chromatography–multi-angle laser-light scattering analysis. After acid hydrolysis, oven-dried samples showed a significantly lower degree of polymerization than never-dried samples. In addition, oven-dried samples showed a unimodal and narrow molar mass distribution, whereas never-dried samples showed a bimodal distribution after acid hydrolysis. These results indicated that oven-drying induces the disordered regions along the cellulose microfibril and that the disordered regions are cleaved by acid hydrolysis. [ABSTRACT FROM AUTHOR]

There are different activation pathways for the oxidation of cellulose by the periodate-chlorite system: thermal activation, chemical activation and cellulosic pulp activation using chemical or mechanical pretreatments. This study aimed to compare the different possible activation methods applied on cellulose, focusing on their effects at the molecular scale (cellulose chain oxidation and degradation) and at the cell wall scale (visualization of oxidized groups locations). It is shown that the activation pathway has an influence on the relation between cellulose carboxylation and depolymerization. A method for analyzing the distribution of carboxyl groups at fiber surface and in the depth of the fiber wall was also developed, including sodium-to-silver ion exchange and SEM imaging with chemical contrast. Important differences in carboxyl group distribution were observed between the diverse activation treatments. Dissolution ability of oxidized PHK pulp at 3% in an alkaline aqueous solution was also assessed. The comprehensive comparison of the activation methods revealed that the combination of mechanical pretreatment and the addition of inert salt during the periodate stage, despite causing only slight oxidation activation, enhances the dispersity of carboxyl groups. This results in a higher dissolution ability in alkaline solvent while maintaining the cellulose DPv (viscosity-average degree of polymerization). [ABSTRACT FROM AUTHOR]

This study investigates the effect of calcined clays (metakaolin, metasilt, metaclay) on the chemical composition, distribution, and structure of alkali–silica reaction (ASR) gels. Using 10 wt% of calcined clays reduced concrete expansion and minimized cracking but did not inhibit ASR gel formation. Micro X-ray fluorescence mapping revealed an average ASR gel content of 3 wt% in concrete, incorporating up to two-thirds of K2O and nearly all Na2O from the binder. Raman spectroscopy indicated structural similarities among gels in different concrete mixes, with an increased degree of polymerization in the metakaolin-containing concrete. Automated mineralogy identified four gel phases: Si gel, Ca-Si gel, Al-Ca-Si gel, and Al-Si gel. Ca-Si gels are formed at binder interfaces, while non-swellable Al-bearing gels are mainly formed in metakaolin-containing concrete located within aggregates. This study shows that aluminum can be incorporated into gels in calcined clay concretes, altering their structure and potentially affecting their expansion behavior in concrete. [ABSTRACT FROM AUTHOR]

Solid-state mechanoenzymatic approaches for the production of cellulose nanocrystals from cotton were examined using three commercially available cellulase systems from Trichoderma reesei, Aspergillus niger and a Cellic CTec2 cellulase blend. A rapid and sharp drop in the degree of polymerization, together with the proportional increase in cellulose crystallinity and generation of nanoscale particles, indicates that cotton is extensively transformed to cellulose nanocrystals with just 15 minutes of ball milling of cotton in the presence of the cellulase enzymes. Subsequent aging of the solid reaction mixture at 55 °C did not significantly affect the degree of polymerization, but resulted in higher material losses due to the increased production of glucose. These results reveal that the endo-activity of the commercial cellulase preparations on cellulose is particularly efficient in solid reaction mixtures (solid loading 50 wt%), allowing for a rapid acid-free generation of cellulose nanocrystals with as low as 0.085 wt% enzyme loading. [ABSTRACT FROM AUTHOR]

The document "Chemical Conservation of Paper-Based Cultural Heritage" discusses the importance of preserving paper-based artifacts, such as ancient books and manuscripts, to protect human civilization's development. Various studies highlighted in the document focus on the properties, degradation mechanisms, and conservation methods of paper artifacts, including the effects of hemicellulose on paper strength, the influence of environmental conditions on palm leaf manuscripts, and the use of innovative materials like soymilk and nanocellulose for paper sizing and reinforcement. The research aims to provide insights into more efficient and sustainable conservation practices for cultural heritage preservation. [Extracted from the article]

Recent developments in the synthesis of substituted polyacetylenes have considerably benefitted from advancements in organometallic catalysis; however, most important developments rely on the advent of Rh-catalyzed living polymerizations. The latter not only allow the tailoring of well-defined degrees of polymerization with low and narrow polydispersity but also enable access to stereochemical well-defined cis-transoidal polymers with a helical structure. These novel polymers open new avenues for application in photonics and electronics. Rh-catalyzed living polymerizations are mild and concise metal-catalyzed polymer syntheses that not only allow for the decoration of sidechains with multiple functionalities, including chiral units, but also enable enantioselective induction of helical chirality, memory of chirality, well-defined copolymerization, and end-group functionalization at both termini. This review summarizes recent developments in metal-catalyzed syntheses of substituted polyacetylenes, with a special focus on Rh-catalyzed living polymerizations. [ABSTRACT FROM AUTHOR]

Gasification slag is the solid waste produced in the process of coal gasification. China produces approximately 30 million tons of gasification slag every year, which urgently needs to be recycled in an efficient and sustainable way. This paper discusses the feasibility of using gasification slag as a supplementary cementitious material (SCM). The working properties, mechanical properties, and microstructure of cement paste after the addition of gasification slag were studied and compared with those of pure cement paste. The results indicate that the hydration products of the composite paste contain a significant amount of Ca(OH)2 and C-S-H gel when the content of gasification slag is less than 30%. However, when the gasification slag content exceeds 30%, the primary hydration product shifts to the C-A-S-H gel. Furthermore, the C-(A)-S-H gel tends to exhibit a lower calcium–silicon ratio and a higher degree of polymerization as the gasification slag content increases. Specifically, the Ca/Si ratio of the 60% C-A-S-H gel is 1.66, with a degree of polymerization of 0.77. When the gasification slag content is maintained at or below 30%, the compressive strength of the gasification slag cement paste decreases by approximately 3.7% to 9.3% compared with that of Portland cement (PC). Nevertheless, the composite cement meets the design requirements of 42.5 composite Portland cement. Thus, gasification slag has emerged as a promising supplementary cementitious material (SCM), with significant potential for widespread application. [ABSTRACT FROM AUTHOR]

A simple method was developed to produce polymeric nanoribbons and other nanostructures in water. This approach incorporates a perylene diimide (PDI) functionalized by triethylene glycol (TEG) as a hydrophobic supramolecular structure directing unit (SSDU) into the core of hydrophilic poly(N,N‐dimethylacrylamide) (PDMAc) chains using RAFT polymerization. All PDI‐functional polymers dissolved spontaneously in water, forming different nanostructures depending on the degree of polymerization (DPn): nanoribbons and nanocylinders for DPn=14 and 22, and spheres for DPn>50 as determined by cryo‐TEM and SAXS analyses. UV/Vis absorption spectroscopy was used to monitor the evolution of the PDI absorption signal upon dissolution. In solid form, all polymers show a H‐aggregate absorption signature, but upon dissolution in water, the shortest DPn forming nanoribbons evolved to show HJ‐aggregate absorption signals. Over time, the J‐aggregate band increased in intensity, while cryo‐TEM monitoring evidenced an increase in the nanoribbon's width. Heating the nanoribbons above 60 °C, triggered a morphological transition from nanoribbons to nanocylinders, due to the disappearance of J‐aggregates, while H‐aggregates were maintained. The study shows that the TEG‐PDI is a powerful SSDU to promote 2D or 1D self‐assembly of polymers depending on DPn through simple dissolution in water. [ABSTRACT FROM AUTHOR]

The technology for direct extraction of porang glucomannan (PG) from fresh tubers offers a faster and simpler process, yielding high-purity glucomannan. However, PG's high viscosity and low solubility limit its use in the food, pharmaceutical, and health industries. Enzymatic hydrolysis of PG has the potential to improve these characteristics and enhance its prebiotic activity. This study aimed to examine the characteristics and prebiotic activity of porang glucomannan hydrolysate (PGH) derived from glucomannan extracted directly from the fresh tubers. PG was hydrolyzed under optimal conditions at 37.6 °C for 3 h, pH of 6.8, and an E/S of 0.8 % (w/w). Analysis of PGH included the degree of polymerization (DP), molecular weight (MW), viscosity, and solubility. Changes in the morphology, molecular structure, and composition of PGH were assessed through scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and high-performance liquid chromatography (HPLC), respectively. Prebiotic activity analysis was conducted by determining the prebiotic activity score in vitro. The results revealed that PGH was composed of 58 % mannohexaose, 40 % mannotriose, and 2 % mannobiose. Notably, PGH exhibited reduced granule size and a porous surface. FTIR analysis indicated a structural change in the PGH molecule after hydrolysis. The DP of PG decreased by 1000 times, and the MW decreased by 60 times, leading to a 700-fold reduction in the viscosity of PGH. In contrast, the solubility of PGH increased threefold, attributed to the disruption of glycosidic and hydrogen bonds between and within glucomannan molecules during hydrolysis. These modifications in PGH characteristics make it more readily fermentable by several Lactobacilli and Bifidobacteria without stimulating the growth of E. coli, resulting in a positive prebiotic activity score. As a result, PGH shows promise as a source of prebiotics and can be utilized in beverage products to enrich their nutritional value, consequently producing functional food. [ABSTRACT FROM AUTHOR]

The effect of key experimental factors on phloridzin oligomerization catalyzed by Trametes versicolor laccase was investigated, and biological activity of synthesized oligomers was evaluated. Mass spectrometry analysis of the obtained reaction mixture showed the presence of oligomers with the degrees of polymerization two and three with dimer as the major product. The detected masses of the formed oligomers indicated the repetition of phloridzin units in their structure and the loss of two hydrogen atoms during the linkage formation, while NMR analysis of the major dimer confirmed the presence of two phloridzin molecules linked via a C5-C5 bond. The effect of temperature, substrate, and enzyme concentration on phloridzin conversion and products' yield was examined, and for achieving the highest products yield (4.1 mg/ml), optimal factors were 40 °C temperature, 5 mg/ml phloridzin concentration and 0.5 mg/ml laccase concentration. Synthesized oligomers showed good antioxidant activity compared to phloridzin and very good potential to be used as skin prebiotics since they exhibited inhibitory effect on opportunistic pathogen Staphylococcus aureus and stimulating effect on commensal bacteria Staphylococcus epidermidis in a broad range of tested concentrations. The highest prebiotic capacity was demonstrated at a concentration of 0.0195 mg/ml in S. epidermidis and S. aureus co-culture. [Display omitted] • Laccase-catalyzed phloridzin oligomers synthesis was optimized. • Oligomers of up to three phloridzin units were detected. • Dominant product, dimer molecule, has two phloridzin units connected via C5-C5 bond. • Oligomers showed good potential to be used as skin prebiotics. [ABSTRACT FROM AUTHOR]

Rapid prototyping has a wide range of applications across various fields, both in industry and for private use. It enables the production of individual parts in a short time, independent of supply chains, which is particularly important in remote locations. Among all 3D printing technologies, stereolithography using photo resins is the most accessible and offers the highest printing quality. However, the strength properties of parts made from photo resins remain a critical concern. In this study, we conducted experimental research to investigate the effect of load vector orientation under uniaxial compression on the elastic and mechanical properties of 3D-printed cylindrical samples. The results revealed that samples with layers oriented at 60° to the load vector exhibited the highest strength, while those with layers at 30° to the load vector showed the lowest strength. Samples with layers aligned parallel or perpendicular to the load vector demonstrated similar strength properties. Under quasi-elastic loading, samples with layers parallel to the load vector exhibited the highest Young's modulus and the lowest Poisson's ratio. Conversely, samples with layers oriented at 30° to the load vector displayed the highest Poisson's ratio. Microstructural analysis revealed that the anisotropy in the mechanical properties of the 3D-printed samples is attributed to the layered, heterogeneous structure of the photoresin, which exhibits varying degrees of polymerization along the printing axes. The upper part of each layer, with a lower degree of polymerization, contributes to the ductile behavior of the samples under shear stresses. In contrast, the lower part of the layer, with a higher degree of polymerization, leads to brittle behavior in the samples. [ABSTRACT FROM AUTHOR]

Erythritol is a sweetener polyol widely distributed in nature. Its industrial production is based on biotechnological fermentative processes using yeasts. It is used essentially in nutrition and pharmaceutical fields. However, due to its still high price, the use of erythritol is not widespread and is lower than that of other polyols. The use of erythritol for polymer synthesis remains largely unexplored by the scientific community. This work describes the synthesis and characterization of polyester, poly (erythritol sebacate) (PES), obtained by thermal polycondensation of erythritol and sebacic acid in a two steps approach. A prepolymerization step was realized at different temperatures (150 °C, 160 °C and 170 °C, respectively) followed by a cure step at 150 °C. It was found that using a higher temperature allows the same degree of polymerization (50%) to be achieved in a shorter period, but this leads to prepolymers with a more heterogeneous oligomeric composition. This is reflected in the final properties of the polymers after curing. Synthesis at 150 °C produced a polymer with superior mechanical performance (ultimate tensile strength: 0.5 MPa; Young's modulus: 0.44 MPa: elongation at break: 123%) and higher chemical resistance to solvents than polymers synthesized at 160 °C and 170 °C. The glass transition temperature (Tg) is between − 20 and 0 °C for all polymers and density is 1.08 g/cm3. Based on these results, we believe that PES is a good elastomer with tunable properties and potential for selective absorption of molecules, such as ethanol, that could be useful for beverage industry and biotechnological applications. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSIt has been claimed that Atractylodes macrocephala applied as a traditional Chinese medicinal herb for centuries, owing to its excellent immunomodulatory and hepatic protective properties. This study aims to explore the immunomodulation of oligosaccharides obtained by gastrointestinal digestion after oral administration of A. macrocephala polysaccharide (xyloglucomannan, XGM). The analysis of chemistry showed that XGM consisted of D-glucose, D-mannose, and D-xylose in a molar ratio of 6.8:3.0:1.0, and the molecular weight was 5465 Da. Furthermore, HCl and pancreatic amylase were used to simulate digestive tract hydrolysis of polysaccharides, obtaining two XGM hydrolysates (XGM-AH and -EH). Oligosaccharide identification results indicated that both XGM-AH and XGM-EH contained glucans (degree of polymerization, DP = 2 ∼ 5). XGM-AH had a wider variety of oligosaccharides than XGM-EH, mainly glucomannans. In vitro immunostimulatory assay indicated that XGM could effectively stimulate the activation and enhance the phagocytosis of RAW264.7 cells. In contrast, XGM-AH and -EH exhibited anti-inflammatory effects, inhibited lipopolysaccharide (LPS)-induced aberrant activation of macrophages, reduced the release of cytokines of macrophages. Flow cytometry assay suggested that XGM-AH and -EH inhibited LPS-induced M1-type polarization of macrophages. In conclusion, XGM-derived oligosaccharides possess anti-inflammatory bioactivities and exhibit differential macrophage regulatory behaviors in contrast to the immune-activating effects exhibited by the prototype polysaccharides.A homogeneous polysaccharide from A. macrocephala was identified as unique xyloglucomannan.XGM hydrolyzed by HCl and pancreatic amylase generated specific oligosaccharide mixtures, and XGM-AH had a wider variety of oligosaccharides compared with XGM-EH.XGM and its hydrolyzed oligosaccharide mixtures exhibited differential modulatory behaviors on macrophage.A homogeneous polysaccharide from A. macrocephala was identified as unique xyloglucomannan.XGM hydrolyzed by HCl and pancreatic amylase generated specific oligosaccharide mixtures, and XGM-AH had a wider variety of oligosaccharides compared with XGM-EH.XGM and its hydrolyzed oligosaccharide mixtures exhibited differential modulatory behaviors on macrophage. [ABSTRACT FROM AUTHOR]

To further elucidate the mechanism of high‐efficiency deep dephosphorization using the duplex method, the morphology, mineral phase structure, and phosphorus aggregation behavior of the CaO–SiO2–FeO–P2O5 slag system with varying FeO content and basicity are analyzed using fourier transform infrared spectrometer, X‐ray diffractometer (XRD), and scanning electron microscope‐energy dispersive spectrometer. XRD analysis reveals that as the FeO content increases, FeO combines with SiO2 and CaO to form the Ca3Fe2(SiO4)3 phase. Observation of the dephosphorization slag's morphology reveals that, at a basicity of 1.8, an increase in FeO content from 10% to 30% leads to the aggregation and growth of the phosphorus‐rich phase, accompanied by an increase in phosphorus content. When the basicity of slag is 2.8 and the content of FeO is 35%, phosphorus is distributed in matrix phase and iron‐rich phase, but the content of phosphorus in all phases is low. The increase in both FeO content and basicity disrupts the polymerization degree of the structure, leading to an increase in the content of low‐polymerization Qn(Si) species and thereby reducing phosphorus accumulation on the silicon–oxygen network. This study provides a theoretical basis and practical guidance for iron and steel enterprises aiming to produce low‐phosphorus and ultralow‐phosphorus steel through the double‐dephosphorization process. [ABSTRACT FROM AUTHOR]

The theory of Odle et al. for the z‐average of branched polycondensates is extended to the general case of co‐cross‐linking of primary chains with different functionalities. Examples are given for free radical and step growth polymerization. For polycondensates, assuming surplus of one functionality and complete conversion, a simple formula for the degree of polymerization DPz for functional groups is derived: 1 DPz=fw3(2gz−gw3)+gw3(2fz−fw3)fwgw(1−(fw−1)(gw−1))2$$\begin{equation} DP_z =\frac{f_w^3(2g_z-g_w^3)+g_w^3(2f_z-f_w^3)}{f_w g_w(1-(f_w-1)(g_w-1))^2} \end{equation}$$(fw, fz, gw, gz: weight and z‐averages of the functionalities of the monomers). The formula is applied to the branched step growth polymerization of monomers A2 + Af +B2 with reactive groups A and B and functionalities 2 and f > 2. The functionality f has practically no influence on the weight averages DPw and Mw if calculated as a function of the relative branching density ρr = ρ/ρc, where ρc = Af, c/(Af, c + A2) and Af, c is the critical value at the gel point. The z‐averages become increasingly larger with increasing f and the ratio DPz(f)/DPz(f = 3) is linear in ρr and f. [ABSTRACT FROM AUTHOR]

Proanthocyanidins (PAs) are a class of polymers composed of flavan-3-ol units that have a variety of bioactivities, and could be applied as natural biologics in food, pharmaceuticals, and cosmetics. PAs are widely found in fruit and vegetables (F&Vegs) and are generally extracted from their flesh and peel. To reduce the cost of extraction and increase the number of commercially viable sources of PAs, it is possible to exploit the by-products of plants. Leaves are major by-products of agricultural production of F&Vegs, and although their share has not been accurately quantified. They make up no less than 20% of the plant and leaves might be an interesting resource at different stages during production and processing. The specific structural PAs in the leaves of various plants are easily overlooked and are notably characterized by their stable content and degree of polymerization. This review examines the existing data on the effects of various factors (e.g. processing conditions, and environment, climate, species, and maturity) on the content and structure of leaf PAs, and highlights their bioactivity (e.g. antioxidant, anti-inflammatory, antibacterial, anticancer, and anti-obesity activity), as well as their interactions with gut microbiota and other biomolecules (e.g. polysaccharides and proteins). Future research is also needed to focus on their precise extraction, bioactivity of high-polymer native or modified PAs and better application type. Highlights: The Leaf proanthocyanidins (LPAs) are mostly oligomeric procyanidins, with a small proportion of leaves containing A-type procyanidins. Foliage is a sustainable source of PAs. LPAs are a potential source of valuable bioactive compounds. The content, structure, extraction and identification and bio-activity of LPAs are discussed. Processing improvement is beneficial to enhance the production of LPA. [ABSTRACT FROM AUTHOR]

The viscosity of CaO‐SiO2‐MgO‐Al2O3‐BaO‐MnO slag with a varying MnO content of 0–8 wt% is continuously measured, and the polymerized network changes are clarified by Fourier transform infrared reflection spectroscopy and X‐ray photoelectron spectroscopy. Thermodynamic calculation and X‐ray diffraction analysis are conducted to determine crystal phases variations. Finally, the relationship between viscosity and different structural parameters is discussed. The results indicate that an increase in MnO content decreases the viscosity from about ≈0.55 to 0.41 Pa·s at 1500 °C, and from 1.3 to 0.87 Pa·s at 1400 °C. The free running temperature also decreases. Ba2+ and Ca2+ are used for charge compensation of [AlO4], and Mn2+ mainly connects nonbridging oxygen to depolymerize the silicate network. The precipitation of crystal phases significantly increases the viscosity of the slag, and Mn2+ is mainly involved in the formation of silicate phases. Structure analyses suggest that an increase in MnO leads to a decrease in the amount of bridging oxygen, which reduces the degree of polymerization. In the composition range of blast furnace slag, the structural parameters change within a narrow range, and the viscosity has a negative correlation with NBO/T and optical basicity, yet a positive correlation with Q. [ABSTRACT FROM AUTHOR]

Despite considerable interest in heteroatom‐containing conjugated polymers, there are only few examples with heavier p‐block elements in the conjugation path. The recently reported heavier acyclic diene metathesis (HADMET) allowed for the synthesis of a polymer containing Ge=Ge double bonds—albeit insoluble and with limited degree of polymerization. By incorporation of long alkyl chains, we now obtained soluble representatives, which exhibit degrees of polymerization near infinity according to diffusion‐ordered NMR spectroscopy (DOSY) and dynamic light scattering (DLS). UV/Vis and NMR data confirm the presence of σ,π‐conjugation across the silylene‐phenylene linkers between the Ge=Ge double bonds. Favorable intermolecular dispersion interactions lead to ladder‐like cylindrical assemblies as confirmed by X‐ray diffraction (XRD), small angle X‐ray scattering (SAXS) and DLS. AFM and TEM images of deposited thin films reveal lamellar ordering of extended polymer bundles. [ABSTRACT FROM AUTHOR]

A dual zwitterionic diblock copolymer (M100C100) consisting of poly(2‐(methacryloyloxy)ethyl phosphorylcholine) (PMPC, M) and poly(3‐((2‐(methacryloyloxy)ethyl) dimethylammonio) propionate) (PCBMA, C) is synthesized via reversible addition‐fragmentation chain transfer (RAFT) polymerization. A double hydrophilic diblock copolymer (M100S100) consist of PMPC and anionic poly(3‐sulfopropyl methacrylate potassium salt) (PMPS, S) is synthesized via RAFT. The degrees of polymerization of each block are 100. The charges of PMPC are neutralized intramolecularly. At neutral pH, the charges in PCBMA are also neutralized intramolecularly due to its carboxybetaine structure. Under acidic conditions, PCBMA exhibits polycation behavior as the pendant carboxy groups become protonated, forming cationic tertiary amine groups. PMPS shows permanent anionic nature independent of pH. Charge neutralized mixture of cationic M100C100 and anionic M100S100 in acidic aqueous solution forms water‐soluble polyion complex (PIC) micelle owing to electrostatic attractive interactions. The core is composed of the cationic PCBMA and anionic PMPS blocks, with the PMPC blocks serving as shells that covered the core surface, forming spherical core–shell PIC micelles. Above pH 4 the pendant carboxy groups in PCBMA undergo deprotonation, transitioning to a zwitterionic state, thereby eliminating the cationic charge in PCBMA. Therefore, above pH 4 the PIC micelles are dissociated due to the disappearance of the charge interactions. [ABSTRACT FROM AUTHOR]

In this study, several hydrogen‐bonded arylamide foldamers (compounds 1–5) with the same degree of polymerization were designed and synthesized. The polyfluoroiodobenzene or iodoethynyl polyfluoroiodobenzene segment was modified as a halogen donor at the end of the monomer, and pyridine or pyridine oxynitride served as the corresponding halogen acceptor segment. The crystal structure of compound 1 indicates that the supramolecular double helices were constructed by stacking a P helix and an M helix in an antiparallel manner in the direction of intermolecular I⋅⋅⋅−O−N+ halogen bonding. The zig‐zag‐shaped linear structures of compounds 2 and 3 were generated under the induction of intermolecular I⋅⋅⋅N and I⋅⋅⋅−O−N+ halogen bonds. [1+1] near‐planar bimolecular supramolecular macrocycles in compounds 4 and 5 were formed by multiple groups of effective intramolecular three‐center hydrogen bonding and strong I⋅⋅⋅N and I⋅⋅⋅−O−N+ halogen bonds. Hirshfeld surface analysis and theoretical modelling of the halogen bonding energy were performed. The noncovalent interactions on the surface of the monomers and the halogen bonding energy were investigated in detail. [ABSTRACT FROM AUTHOR]

The mechanical properties and structural evolution of sodium borosilicate glasses under the uniaxial tensile process were investigated through molecular dynamics simulation. The simulated properties of sodium borosilicate glasses were in good agreement with the experimental values. [BO 3 ] and Na+ compensated [BO 4 ] groups were generated in the glass network in low boron content, while [BO 3 ] appeared with increasing boron oxide. The structure descriptor, F net synthesized the structure and energy information of the glass network which was positively correlated with Young's modulus. The strength has been diminished due to the decreased degree of polymerization of the glass network and the migration of Na+ cations. Simultaneously, the elastic deformation of sodium borosilicate glass arose from the motion of Na+ cations and alterations in the Si-O-Si bond angle. Moreover, the plastic deformation of sodium borosilicate glasses was attributed to the transition from [BO 4 ] to [BO 3 ] and the higher mobility of [BO 3 ] than [BO 4 ] and [SiO 4 ]. [ABSTRACT FROM AUTHOR]

Taxodium 'Zhongshanshan' is a distinctive tree known for its rapid growth and robust stress resilience. To enhance the utilization of forestry resources, tannin extracts were procured from the barks (BE) and leaves (LE) of Taxodium 'Zhongshanshan'. The tannin structures were characterized by FT-IR and MALDI-TOF MS, and found to be condensed tannin with a degree of polymerization not exceeding 6. The tannin extracts exhibited a potent ability to scavenge free radicals at capacities of 60–80 % compared to Vitamin C (VC). They inhibited the bacterial strains Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with a pronounced effect on the latter. Furthermore, tannin from Taxodium 'Zhongshanshan' appears benign and have no significant effect on cell activity. [ABSTRACT FROM AUTHOR]

In low‐density polyethylene (LDPE) production, low‐molecular‐weight species are used as chain transfer agents (CTAs). They reduce the degree of polymerization, which has an impact on the polymer properties, such as processability. To specifically adjust the product properties, a detailed understanding of the transfer kinetics to CTAs is indispensable. Thus, the transfer activity of various primary, secondary, and tertiary alcohols as well as diols was investigated experimentally between 120 °C and 250 °C at 2000 bar. The results were evaluated using the Mayo and chain length distribution (CLD) method, and the latter was found to give more reliable results. It was observed that the hydroxy group systematically increases transfer activity compared to alkanes. Additionally, a linear increase of transfer activity with the number of hydrogen atoms is found. [ABSTRACT FROM AUTHOR]

Handmade papers, as carriers of paper-based cultural relics, have played a crucial role in the development of human culture, knowledge, and civilization. Understanding the intricate relationship between the structural properties and degradation mechanisms of handmade papers is essential for the conservation of historical documents. In this work, an artificial dry-heat-accelerated aging method was used to investigate the interplay among the mechanical properties of paper, the degree of polymerization (DP) of cellulose, the chemical composition, the hydrogen bond strength, the crystallinity, and the degree of hornification for paper fibers. The results demonstrated for the first time that the mechanical properties of handmade bamboo paper exhibited an initial plateau region, a rapid decline region, and sometimes a second plateau region as it undergoes a dry-heat aging process. The changes in cellulose, hemicellulose, and lignin content were tracked throughout these three stages. The lignin content was relatively stable, while the cellulose and hemicellulose content decreased, which was consistent with the observed decline in mechanical properties. When the DP of cellulose decreased to the range of 600–400, there was a critical point in the mechanical properties of the paper, marking a transition from the initial stable region to a rapid decline region. The fiber embrittlement caused by cellulose chain breakage resulting from the decrease in DP was counteracted by the enhancement of intermolecular hydrogen bonds and the hornification process. A second stable region appeared when the DP was less than 400, marking a transition from a balanced or slightly decreasing trend in the initial plateau region to a sharp decline. This study also discussed for the first time that the formation of the second plateau region may be due to the presence of hemicellulose and lignin, which hinder the further aggregation of cellulose and maintain the structural stability of the fiber cell. The findings of this study can provide guidance for improving ancient book preservation strategies. On the one hand, understanding how these components affect the durability of paper can help us better predict and slow down the aging of ancient books. On the other hand, specific chemical treatment methods can be designed to stabilize these components and reduce their degradation rate under adverse environmental conditions. [ABSTRACT FROM AUTHOR]

As a promising polymer for the production of biomaterials and drug delivery systems, poly(lactic acid) (PLA) is characterized by its relative hydrophobicity, as well as its chemical and biological inertness. Here, we aimed to improve the biological properties of PLA-based materials via the covalent attachment of a hydrophilic biocompatible glycopolymer, namely poly(2-deoxy-N-methacrylamido-D-glucose) (PMAG) on their surface. PMAG is a water-soluble polymer that contains glucose units in its side chains, which are responsible for good biocompatibility and the ability to attach bioactive molecules. In the developed protocol, PMAG was synthesized by controlled radical polymerization in the presence of a reversible addition–fragmentation chain transfer (RAFT) agent, followed by the conversion of glycopolymer terminal dithiobenzoate functionality into a primary amino group (PMAG-NH2). PLA-based films served as model aliphatic polyester materials for developing the surface biofunctionalization protocol. According to that, PMAG-NH2 covalent immobilization was carried out after alkali treatment, allowing the generation of the surface-located carboxyl groups and their activation. The developed modification method provided a one-point attachment of hydrophilic PMAG to the hydrophobic PLA surface. PMAG samples, which differed by the degree of polymerization, and the variation of polymer concentration in the reaction medium were applied to investigate the modification efficacy and grafting density. The developed single-point polymer grafting approach provided the efficient functionalization with a grafting density in the range of 5–23 nmol/cm2. The neat and modified polymer films were characterized by a number of methods, namely atomic force microscopy, thermogravimetric analysis, ellipsometry, and contact angle measurements. In addition, an ArgGlyAsp-containing peptide (RGD peptide) was conjugated to the PMAG macromolecules grafted on the surface of PLA films. It was shown that both surface modification with PMAG and with PMAG-RGD peptide enhanced the adhesion and growth of mesenchymal stem cells as compared to a neat PLA surface. [ABSTRACT FROM AUTHOR]

Immobilized enzyme reactors (IMERs) are critical tools for developing novel oligosaccharides based on the enzymatic catalysis of polysaccharides. In this paper, a novel glucuronan lyase from Peteryoungia rosettiformans was produced, purified, and then immobilized on a CIM® CDI disk for cleaving glucuronan. The results showed that around 63.6% of glycuronan lyases (800.9 μg) were immobilized on the disk. The Vmax values of immobilized glucuronan lyases did not significantly change (56.9 ± 4.7 μM∙min−1), while the Km values (0.310 ± 0.075 g∙L−1) increased by 2.5 times. It is worth noting that immobilized glucuronan lyases overcame the catalytic inhibition of free enzymes observed under high glucuronan concentrations (0.5–2 g∙L−1). circumscribed central composite design (CCCD) and response surface methodology (RSM) showed that glucuronan concentration, flow rate, and reaction time significantly affected the yield of oligoglucuronans. The degree of polymerization (DP) of degraded glucuronan ranged from DP 2–8 according to the results obtained by high performance anion exchange chromatography coupled with a pulsed amperometric detector (HPAEC-PAD). The IMER retained 50.9% activity after running 2373 column volumes of glucuronan. Finally, this glucuronan lyase reactor was tentatively connected to an immobilized laccase reactor to depolymerize, and gallic acid (GA) was added to glucuronan. Approximately 8.5 mg of GA was added onto 1 g of initial glucuronan, and the GA–oligoglucuronan conjugates showed notable antioxidant activity. [ABSTRACT FROM AUTHOR]

Poly(δ-valerolactone) (PVL) is a polymer that has garnered significant researcher interest due to its intriguing features and prospective uses across numerous domains, particularly in medicine. This work aimed to assess the influence of the Lewis acidity of the bis(β-diketonate)Zr catalyst complex on the ring-opening polymerization of δ-valerolactone. The ligand in the compound contains an electron-donating group, specifically the methyl group (2a). Furthermore, electron-withdrawing groups employed include phenyl (2b–2c) and trifluoromethyl groups (2d). Characterization data indicate that PVL has been successfully synthesized with a bis(β-diketonate)Zr complex catalyst. The hierarchy of Lewis acid strength for the bis(β-diketonate)Zr complex is 2c > 2b > 2d ≫ 2a. The sequence of PVL DP from highest to lowest is 2b, 2c, 2d and 2a. Nonetheless, the elevated Lewis acidity of complex 2c does not provide PVL with the greatest degree of polymerization. The steric barrier of complex 2c, which contains two phenyl groups, is larger than that in complex 2b. Consequently, the coordination process of the nucleophilic monomer with the electrophilic zirconium central atom becomes increasingly difficult. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Nitrogen‐containing polymers have found a wide myriad of applications in materials science and other different areas, and have attracted much attention towards the development of new synthetic methods. Ring‐opening metathesis polymerization represents an area of great versatility and potential for the synthesis of highly functionalized polymers with low dispersity and control over molecular weight and architecture complexity. Expanding the scope of monomers through the incorporation of nitrogen atoms would further expand their utilities. In this work, a controlled synthesis of polymers with in‐chain enamide moiety through ring‐opening metathesis polymerization was developed by utilizing azetine derivatives as the monomers. Relatively short synthetic routes were designed and generated a panel of five monomers. The polymerization exhibited living characteristics, as linear relationship between molecular weights and degrees of polymerization and relatively narrow molar mass distributions were observed, which was further confirmed by successful diblock copolymers formation through sequential addition of two monomers. The resulting polymers that contain the enamide moiety within the backbone exhibited good stability and underwent facile degradation under acidic conditions. [ABSTRACT FROM AUTHOR]

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The TEMPO-mediated oxidation is one of the most popular methods to prepare cellulose nanofibers due to its easy operation, high oxidation efficiency and resulting high aspect ratio nanofibers with uniform size. Among TEMPO-mediated oxidation methods, the TEMPO/NaBr/NaClO (TBN) oxidation system is the most commonly used and has the highest oxidation efficiency. However, cellulose suffers from the degradation by NaClO in TBN oxidation, which can be directly reflected in the reduction of degree of polymerization of cellulose. In this paper, we explored the effect of the content of NaClO on oxidation and figured out an optimization method where NaClO was added periodically for TBN oxidation system (semi-batch process) that could efficiently oxidize hardwood bleached kraft pulp (HBKP) cellulose while reducing the degradation. This phenomenon is most obvious when the addition amount of NaClO is 10 mmol/g and the reaction time is 7.5 h, the carboxyl content of the TEMPO oxidized cellulose obtained by adding NaClO in different methods has no significant change (both are around 1.5 mmol/g), but the degree of polymerization of TEMPO oxidized cellulose obtained by adding NaClO periodically is 2.3 times that of TEMPO oxidized cellulose obtained by adding NaClO in one batch. This optimization method provides a feasible way for the adjustable preparation of nanofibers with high carboxyl content by maintaining relative high degree of polymerization. [ABSTRACT FROM AUTHOR]

The effect of lignin on several properties of nanocellulose suspensions and films, such as degree of mechanical fibrillation, optical transparency, and gas barrier properties is still a matter of study. In the present work, it was investigated the influence of residual lignin on the efficiency of cationization and enzymatic pretreatments to produce lignin-containing nanocelluloses (LCNFs) from unbleached kraft pulps, and, on the properties (mechanical, gas barrier, transparency, antioxidant activity and thermal stability) of the corresponding films. The overall efficiency of the pretreatments was not negatively affected by the presence of lignin (3–4 wt%) in the starting pulps, as measured by the degree of fibrillation, degree of polymerization of cellulose, optical transmittance, and cationic group content (cationization). On the contrary, lignin could even enhance the mechanical fibrillation and the optical transmittance (transparency) of the cationic and enzymatic LCNF suspensions compared to the reference lignin-free nanocelluloses (CNFs) prepared from bleached pulp. Lignin could also improve the optical transparency of the films, which is an important finding of the present work: 64.8% for LCNF-Cationic (-Cat) vs. 56.9% for CNF-Cat, and 74.5% for LCNF-Enzymatic (-Enz) vs. 64.5% for CNF-Enz. Moreover, films with lignin demonstrated higher antioxidant activity, UV-light absorption capacity, larger char residue, and even improved oxygen barrier compared to the analogous CNF films. A remarkable oxygen barrier performance was exhibited by the LCNF-Enz film (oxygen transmission rate below 2 cm3/m2.day). Overall, the presence of residual lignin in the cellulose micro/nanofibril production can improve some of the suspension and film properties, particularly the optical transparency. [ABSTRACT FROM AUTHOR]