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In this study, a novel cellulose nanocrystal/metal-organic framework composite (MC) was developed as a stabilizer for alkenyl succinic anhydride (ASA) Pickering emulsions, demonstrating remarkable sizing performance and antimicrobial properties for advanced food packaging applications. The MCs exhibited superior emulsion stabilization capabilities compared to pure metal-organic frameworks, with the optimum MC concentration identified as 1.0 wt% CNC. The hydrophobicity of the sizing paper was found to be enhanced with increasing CNC content. The MC-ASA sized paper demonstrated commendable storage stability, robust gas adsorption, and resistance to water vapor or water droplets. The MCs-ASA sized paper showed excellent food preservation efficacy, maintaining the freshness of strawberries for up to seven days, compared to ASA-sized paper without MCs. The antimicrobial assays targeting Escherichia coli and Staphylococcus aureus highlighted the intrinsic antimicrobial properties of the MCs, contributing to the extended freshness of the encased strawberries. The water vapor barrier efficacy and water retention capabilities of MCs-ASA sized paper were found to be superior to those of the paper without MCs, emphasizing the potential of the developed composite as an innovative and effective food packaging solution. This study offers valuable insights into the synthesis and implementation of CNC/MOF composite particles for versatile applications in food packaging, water-resistant materials, and environmental protection. [Display omitted] • CNC/MOF composites boost ASA Pickering emulsions' sizing performance. • MCs elevate hydrophobicity, gas adsorption, and sizing paper stability. • MCs-ASA paper extends strawberry freshness to 7 days in food packaging. • Research paves way for sustainable, eco-friendly advanced packaging solutions. [ABSTRACT FROM AUTHOR]

Superhydrophobic paper with remarkable durability is of considerable interest for its practical applications. In this study, a scalable, inexpensive, and universal surface sizing technique was implemented to prepare superhydrophobic paper with enhanced durability. A thin layer of starch-based composite, acting as a bio-binder, was first coated onto the paper surface by a sophisticated manufacturing technique called surface sizing, immediately followed by a spray coating of hexamethyl disilazane treated silica nanoparticles (HMDS-SiNPs) dispersed in ethanol on the surface of the wet starch-coated sheet, and the dual layers dried at the same time. Consequently, durable superhydrophobic paper with bi-layer structure was obtained after air drying. The as-prepared superhydrophobic paper not only exhibited a self-cleaning behavior, but also presented an enhanced durability against scratching, bending/deformation, as well as moisture. The universal surface sizing of starch-based composites may pave the way for the up-scaled and cost-effective production of durable superhydrophobic paper. [ABSTRACT FROM AUTHOR]

Stabilizing alkenyl succinic anhydride (ASA) emulsions using fine particles instead of cationic starch have attracted much attention in recent years. Herein, starch nanocrystals (SNCs) made from maize starch by H 2 SO 4 hydrolysis were used to co-stabilize ASA emulsions with fluorescent carbon dots (CDs) made hydrothermally from gelatin. The introduction of CDs can significantly enhance the stability and reduce the droplet size of SNC-stabilized ASA-in-water emulsions. Consequently, the sizing performance of the SNC-stabilized ASA emulsion is significantly improved by increasing the CD-to-SNC mass ratio. SNC and CD co-stabilized ASA emulsions show much better sizing performance than starch and CD co-stabilized ASA emulsions, achieving their best sizing performance at a CD-to-SNC mass ratio of 80%. Meanwhile, the morphology of SNC/starch and CD co-stabilized ASA emulsions can be traced under UV excitation. [ABSTRACT FROM AUTHOR]

• Novel method of measuring the uniformity of liquid penetration through fibrous porous materials was proposed. • Texture entropy and contrast were taken into account in the proposed method. • Correlations between the dynamics of liquid penetration and the examined texture parameters were found. • New parameters were introduced for better evaluation of the nature of the liquid flow through the porous material structure. The interaction of liquids with materials is an important factor influencing many technological processes and describing the quality of the material itself. However, characterization of the wetting and penetration of liquids phenomena through the materials of heterogeneous structure is a very difficult task. Paper is an example of such material. Paper sizing is one of the most important operations in paper technology. Its purpose is to reduce the wettability of the paper. The aim of the present study was to evaluate the suitability of the texture analysis to assess the uniformity of liquid penetration through the paper structure in terms of the degree of the paper sizing. As a result of the research, a new method of measuring was proposed based on dynamic changes in their texture parameters. For this purpose, such texture parameters as entropy and contrast were used. Characteristic points were determined on the curves of the dynamic changes of both parameters. It was proved that there is a correlation between the dynamics of liquid penetration through the paper structure and the examined texture parameters. It was found that the maximum value of entropy and contrast, the time of reaching both values, the points of inflection of the curves during their decrease, and the times by which these points were reached can be useful parameters that provide information about the nature of the liquid flow through the porous material structure. [ABSTRACT FROM AUTHOR]

The surface application of starch is a well-established method for increasing paper strength. In surface sizing, a solution of degraded starch is applied to the paper. Two procedures have proved valuable for starch degradation in the paper mill: enzymatic and thermo-oxidative degradation. The objective of this study was to determine achievable efficiencies of cavitation in preparing degraded starch for surface application on paper. It was found that ultrasonic-assisted starch degradation can provide a starch solution that is suitable for surface sizing. The molecular composition of starch solutions prepared by ultrasonic treatment differed from that of starch solutions degraded by enzymes or by thermo-oxidation. Compared to commercial degradation processes, this resulted in intensified film formation and in greater penetration during surface sizing and ultimately in a higher starch content of the paper. Paper sized with ultrasonically treated starch solutions show the same strength properties compared to commercially sized paper. [ABSTRACT FROM AUTHOR]

The increase of paper size and production speed in wide-format inkjet printing systems is limited by significant in-plane deformation of the paper during printing. To increase both the production speed and paper size, the compensation of paper deformation is essential. A potential approach to compensate the paper deformation is actively changing the longitudinal paper position during a lateral pass of the printheads. This paper aims at developing an Iterative Learning Control (ILC) algorithm suited for this compensation strategy. The paper position is measured directly, but in non-real-time using image data obtained with a scanner located at the printheads. The proposed controller is experimentally validated and compared with standard norm-optimal ILC in a reproducible experiment, where a set of benchmark trajectories is used that represents severe paper deformation. The results show that in contrast to standard ILC, the ILC with basis functions achieves good tracking performance for the reference set and is hence a proper candidate algorithm for the compensation strategy. [ABSTRACT FROM AUTHOR]

Alkenyl succinic anhydride (ASA) is a widely used paper sizing agent that is applied in the form of oil-in-water (o/w) emulsions in order to impart a water-resistant character to the resulting paper. To obtain stable o/w emulsions of ASA, laponite, a highly hydrophilic synthetic clay, was selected as the stabilizer after it had been modified with tetramethylammonium chloride (TMAC), a quaternary ammonium salt with the shortest possible hydrocarbon groups. It was found that the TMAC moderately neutralized the negative charges of laponite particles, lowered the apparent viscosity, but enhanced the turbidity of laponite aqueous dispersion by enhancing the hydrophobicity of the laponite particles, favoring adsorption of laponite particles on the ASA-water interface. Meanwhile, the TMAC significantly decreased the interfacial tension between ASA and water/aqueous laponite dispersion, promoting the formation of an emulsion with small droplets. When the added amount of TMAC reached 1wt% based on laponite, the as-prepared ASA emulsion had small droplet size, low viscosity and uniform droplet size distribution, and exhibited good creaming/coalescence stability. By using TMAC to modify laponite nanoparticles, the hydrolysis stability and sizing performance of ASA emulsion were also improved. [ABSTRACT FROM AUTHOR]

Abstract: Alkenyl succinic anhydride (ASA) is a viscous polar oil, typically used as a paper sizing agent after being emulsified. ASA and water emulsions stabilized by TiO2 nanoparticles were prepared by adding the aqueous phase to the oil phase. Catastrophic phase inversion from w/o to o/w or w/o/w has been investigated by monitoring the variation of emulsion conductivity with water mass fraction at different homogenization speeds, initial particle locations and particle concentrations. When initially dispersed in water, TiO2 nanoparticles carry positive charge and interact with hydrolyzed ASA at the water–ASA interface. The particles are thus hydrophobically modified, resulting in phase inversion from w/o to w/o/w at higher water mass fraction, while for particles originating in ASA, the phase inverts from w/o to o/w at a lower water mass fraction. Higher homogenization speed and lower particle concentration induce phase inversion at lower water mass fractions. In addition, variations in the phase inversion point caused by the homogenization speed and particle concentration are magnified when the particles originate in water. Similar to non-ionic surfactant-stabilized emulsions prepared by a catastrophic emulsification process, the particle-stabilized emulsions containing ASA exhibit a diminished drop size when approaching the water mass fraction at which phase inversion occurs. Emulsions with the particles initially dispersed in ASA have a slightly smaller drop size than those with particles initially dispersed in water. In addition, the drop size near the phase inversion point did not obviously change with particle concentration. [Copyright &y& Elsevier]

Abstract: This paper reports the development of a new experimental method suitable for the determination of the spreading velocity of surface active substances on a thin film of liquid substrate over a solid surface. Previous research showed that when oil and surfactants spread on the surface of a deep body of water, the spreading velocity is usually quite high, being in the range of several tens of centimeters per second. However, the spreading velocities of these substances on a thin water film are much slower. This is because that the spreading of an oil or a surfactant on water surface is not just a two dimension phenomenon, but a phenomenon involving the movement of water in a small depth below the surface. An additional process impeding oil or surfactant spreading in this situation is the interaction of the spreading molecules with the liquid/soild interface underneath water surface. The experimental method developed in this work uses a Wilhelmy balance to monitor the average spreading velocity of surface active substances on a thin water film over a porous solid substrate. The spreading of cellulose hydrophobization agents over wet paper web during the papermaking process is used as an example to demonstrate the capability of the method. [Copyright &y& Elsevier]

Abstract: Mineral fillers have long been used in papermaking. The furnish of the writing and printing paper depends on using the fillers as internal or surface treatments. Talc, as an Egyptian filler material, was used as it is or after modification to be used as internal sizing for bleached rice straw pulp. Talc was modified chemically with phthalic anhydride and urea, as well as with using rosin size. Talc is chemically inert. The modification was carried out to change the nature of the native talc. The mechanical and optical properties for internal sizing papers were studied. The results indicated that modified talc with phthalic anhydride enhances the mechanical and optical properties for sized hand-sheets. It was clear that modification of the talc plays a role in improvement of the fiber–filler–fiber bond. [Copyright &y& Elsevier]

Compared with conventional acidic rosin emulsion size, neutral rosin size has good sizing efficiency under neutral–alkaline conditions of paper manufacture because its emulsion particles are stable to the action of hydroxide ions. Therefore, the sizing efficiency of emulsion-type rosin sizes, i.e. their ability to increase resistance to fluid penetration, was considered to be related with their particulate structure. The supramolecular structure of the neutral glycerin rosin ester–rosin size microparticles and acidic rosin size microparticles were investigated by using differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) absorption spectroscopy, and electron spectroscopy for chemical analysis (ESCA) techniques in this study. The results indicated that the neutral glycerin rosin ester–rosin size is quite distinct from the acidic rosin sizes in their particulate supramolecular structure. A glycerol dirosinate bilayer existed in the particle structure is hypothesized for the neutral glycerin rosin ester–rosin size microparticles. The results also suggest that the glycerol dirosinate bilayer distributes on the outermost layer of the neutral rosin size microparticles, covering the rosin acid molecules, so as to prevent the dissociation of rosin by hydroxide ions under neutral–alkaline conditions. Consequently, the difference in the supramolecular structure of the rosin sizes particles resulted in their different stabilities and retention characteristics. [Copyright &y& Elsevier]

Utilizing the assembly and formation of laponite/lauric arginate (LAE) complexes near the water-oil interface, where laponite and LAE interact, the stability and preparation of alkyl ketene dimer (AKD) Pickering emulsions with tunable shells were investigated. Stable spherical emulsions were generated with homogenization due to the interfacial jamming of laponite/LAE complexes. The packing density of laponite at the oil/water interface was adjustable via LAE concentration tuning. The Pickering system with a tunable shell, droplet size, resistance to oil agglomeration and hydrolysis over a long period of time was achieved based on LAE loading. Hydrophobic paper with a 126.6° of water contact angle was prepared under a surface sizing process with the laponite/LAE-stabilized AKD emulsion loading of 0.12 wt% LAE, which exhibited 90 days' long-term storage stability. The confocal laser scanning microscopy (CLSM) shows that laponite/LAE forms a dense layer at the oil/water interface and 3D-network in a continuous phase. The properties provided by laponite/LAE, a highly efficient complex with resistance to phase permeability and hydrolysis, open new opportunities in biodegradable and food-grade emulsifiers for paper sizing agents, where LAE achieves synergistic effects with laponite. [Display omitted] • LAE adsorption to laponite notably impacted the properties of laponite. • Using LAE to adsorb to laponite is an environmentally friendly surface modification technique. • pH plays a significant role in AKD emulsion loading of laponite/LAE complexes. • Tunable shells were controllably achieved based on LAE loading. • Long-term storage and sizing performance of AKD can be changed based on LAE loading. [ABSTRACT FROM AUTHOR]

Alkenylsuccinic Anhydride (ASA) is commonly applied as oil-in-water emulsions in papermaking industry. Herein, a particle stabilized ASA emulsion was developed for avoiding the adverse effect of surfactant, further improving the sizing performance and reducing the hydrolysis of ASA Pickering emulsions, where Laponite nanoparticles were employed as a stabilizer of the ASA Pickering emulsions after being modified with carbon nitride quantum dots. It was found that the hydrophilic Laponite particles became partially hydrophobic after being modified with CNQDs in dosage of 20–40 wt%, and thus promoted the formation of emulsions with fine and uniform droplets that resisted creaming/coalescence formation. The adsorption of the Laponite/CNQDs particles on the ASA droplet surface improved the emulsion stability, which was verified by fluorescent confocal laser scanning microscopy. Meanwhile, by using Laponite/CNQDs nanoparticles, the storage stability of ASA Pickering emulsion and its sizing performance on paper was also improved. Unlabelled Image • CNQD adsorption improved the Laponite hydrophobic property and the adsorption efficacy at the ASA-water interfaces. • The Pickering emulsion's stabilization mechanism was adequately illustrated using Laponite/CNQDs as fluorescent probes. • Different concentrations of Laponite do not induce CNQD fluorescence quenching. • Laponite/CNQDs can maintain ASA emulsion stability over extended aging periods and sustain high sizing performance [ABSTRACT FROM AUTHOR]