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AbstractIn this article, n-eicosane@MUF phase change microcapsules were prepared by in-situ polymerization with n-eicosane as the core material and melamine urea-formaldehyde (MUF) resin as the shell material. The effects of pH values from 3.5 to 6.0 on the surface morphology, particle size distribution, latent heat of phase transformation, encapsulation degree, thermal stability, and permeability resistance of the microcapsules were investigated. The results showed that the surfaces of the microcapsules gradually became smooth with the increase of pH value, and their encapsulation degree and impermeability also increased roughly. When the pH = 5.5, the particle size of the microcapsule samples ranged from 1.5 to 9.7 μm, the melting enthalpy was 178.8 J/g, and the encapsulation degree was 86.6%, which had the best thermal stability and impermeability. However, when the pH = 6.0, the phenomenon of microcapsule shell rupture occurred and the above performance no longer occurred. [ABSTRACT FROM AUTHOR]

At present, the use of isocyanate adhesives mostly requires the assistance of solvents, which can cause adverse environmental pollution and health effects. The aqueous isocyanate avoids the shortcomings of the solvent, but shortens the working life of the isocyanate. Isocyanate microcapsules can avoid these shortcomings, and can also solidify isocyanate to improve the efficiency of isocyanate use. In this study, microencapsulation technology was used to protect the highly reactive -NCO group, improve the stability of isocyanate, and prolong the working life of isocyanate in water-based wood adhesives. That is, isocyanate microcapsules with gum Arabic/gelatin as shell and isocyanate as core were prepared in oil-in-water emulsion by complex coacervation. In addition, the preparation process was optimized by changing the parameters. Then, the prepared isocyanate microcapsules were characterized and analyzed by Fourier transform infrared spectrometer, Scanning electron microscope, Particle size analyzer, etc. Finally, plywood was prepared by using the prepared isocyanate microcapsules in the wood adhesive. The results showed that, the particle size of isocyanate microcapsules was controllable, and the content of active groups and core in the prepared isocyanate microcapsules can reach a high level. The isocyanate microcapsules extend the working life of isocyanates from about 30 mins to 5 hours, and significantly improve the stability of isocyanates. The bonding strength of the prepared plywood meets the requirements of (Class I plywood) with only 20% -NCO addition. [ABSTRACT FROM AUTHOR]

Purpose: The efforts of researchers in the 21st century have been devoted to developing novel approaches to leave planet earth green for future generations. This study aims to report the synthesis of microcapsules from natural essential peppermint oil and their application to a bleached polyester and cotton (PC) blended fabric. Design/methodology/approach: Microcapsules were prepared by a complex coacervation process and applied through the conventional pad-dry-cure method. The liquid suspension of the microcapsules was examined by optical microscopy to investigate the surface morphology of the microcapsules. Scanning electron microscopy was used to examine the surface morphology of the fabric after the application of the microcapsules. The finished fabric was checked for its mosquito repellent activity at the lab scale using a standard test protocol (cage test) by inserting a human arm and hand enfolded with microcapsules treated fabric. Findings: PC fabric treated with 6% microencapsulated peppermint oil at zero wash showed 95.3% repellency against mosquitoes, and after 30 washes, the repellency was 85.8% which confirmed the durability of the developed finished fabric. The finished samples exhibited excellent air permeabilities and absorbencies. Originality/value: This study successfully developed peppermint oil microencapsulated fabric with excellent efficacy against three mosquito species. [ABSTRACT FROM AUTHOR]

Microencapsulation technology is a versatile approach that offers effective protection for core materials while also solving issues such as leakage and interface bonding. In this study, a simple yet efficient method for producing multifunctional fabric coatings has been proposed by utilizing chitosan/silica hybrid microcapsules. The synthesis of the microcapsules was achieved through a combination of the single condensation method and the sol-gel method. These microcapsules were specifically designed to encapsulate octadecane and paraffin. The microcapsules were structured with a core-shell configuration, and the shell was functionalized with both fluoroalkyl silane (FAS) and choline phosphate (CP) grafts. The resulting microcapsules were added to silicone resins to produce multifunctional fabric coatings. The desired coatings improved the hydrophilic and hydrophobic properties of the fabrics, with a hydrophilic side contact angle of less than 10 ° and a hydrophobic side contact angle of up to 156 °. In addition, compared with untreated fabrics, coated fabrics can achieve a temperature difference of over 6 °C, demonstrating certain thermal insulation properties. Moreover, the coated fabric exhibits excellent antibacterial properties, with an inhibition rate of over 98% against Escherichia coli and Staphylococcus aureus. The proposed method provides a promising solution for developing advanced multifunctional fabrics with enhanced properties. [ABSTRACT FROM AUTHOR]

The antibacterial microcapsules were prepared by encapsulating Toddalia asiatica (L.) Lam. extracts with urea–formaldehyde resin. The orthogonal test was designed to investigate the effects of the mass ratio of core and wall materials (Wcore:Wwall), emulsifier concentration, reaction temperature and reaction time on the yield rate and coverage rate of microcapsules, and to obtain the best preparation technology for microcapsules. The single-factor results indicated that the maximum influence factor was the Wcore:Wwall of the microcapsules; the larger the Wcore:Wwall, the easier the microcapsules were to agglomerate; and when the Wcore:Wwall was 0.8:1, the coverage rate reached the maximum value of 11.0%. The waterborne topcoat paint film was prepared by adding the microcapsules in the same content. The yield rate, coverage rate, and microscopic morphology of Toddalia asiatica (L.) Lam. extract microcapsules were analyzed, as well as the effects of microcapsules on the microscopic morphology, optical properties, cold liquid resistance, mechanical properties and antibacterial properties of a waterborne topcoat paint film. Combining the optical properties, cold liquid resistance, physical properties, and antibacterial properties of the waterborne topcoat paint film, the comprehensive performance of the waterborne topcoat paint film with the Wcore:Wwall of 0.8:1 was superior. The gloss was 8.07 GU, color difference ΔE was 9.21, visible light transmittance was 82.90%, resistance to citric acid, ethanol and detergent were grade 1, 2 and 2, respectively, elongation at break was 15.68%, and roughness was 3.407 µm. The antibacterial activity against Escherichia coli and Staphylococcus aureus were 42.82% and 46.05%, respectively. In this study, a waterborne topcoat paint film with a microcapsule-coated plant-derived antibacterial agent as the core was prepared, expanding the application prospect of plant-derived antibacterial microcapsules. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis : Microcapsule formation, following internal phase separation by solvent evaporation, is controlled by two main factors of thermodynamic and kinetic origin. Morphology prediction has previously focused on the final thermodynamical state in terms of spreading conditions, limiting the prediction accuracy. By additionally considering kinetic effects as the emulsion droplet evolves through the two-phase region of its ternary phase diagram during solvent evaporation, this should enhance prediction accuracy and explain a wider range of morphologies. Experiments : Dynamical interfacial tensions, and thereby spreading coefficients, during the formation of poly(methyl methacrylate) and poly(d , l -lactic- co -glycolic acid) microcapsules were measured by first establishing the boundaries and tie-lines of the ternary system in the emulsion droplets. Kinetic effects during the formation were investigated by varying the solvent evaporation rate and hence the time for polymer shell formation equilibration. The theory was validated by comparing predicted morphologies to microscopic snapshots of intermediate and final morphologies. Findings : The proposed theory explained both intermediate acorn and core–shell morphologies, where a late transition from acorn to core–shell produced microcapsules containing highly off-centered cores. By considering the kinetic factors, the formulation could be altered from yielding kinetically frozen acorns to core–shell and from yielding multicore to single core microcapsules. [ABSTRACT FROM AUTHOR]

Microfluidics has been applied in the preparation of monodisperse droplets and microcapsules due to its high encapsulation efficiency, its ability to create uniform particle sizes, and its capacity to control core–shell ratio and structure. To bring to the fore methodologies for the fabrication and application of monodisperse microcapsules using microfluidics, we present a review of the design, structure, materials, and surface modification techniques of various microfluidic chips. The review also covers fabrication methods, operating parameters and regulation methods of single and multiple monodisperse emulsion droplets fabricated from various microfluidic devices. Our findings show that particle size of monodisperse droplets depend mainly on microchannel characteristic size and flow rate, with particle size increasing with larger microchannel but decreasing with higher continuous phase flow rate. We additionally reviewed and compared various fabrication methods for monodisperse microcapsules, such as interfacial polymerization, free-radical polymerization, ionic cross-linking, and solvent evaporation. We further reviewed and examined the application of monodisperse microcapsules in biology applications, food engineering, composite materials development, and pharmaceutical industry. We found that high-throughput microfluidics for scale-up monodisperse microcapsule preparation towards uniform degradation and targeted release properties of monodisperse microcapsules would be key innovative direction for future applications. [ABSTRACT FROM AUTHOR]

We report a sensitive method for comparing weak interactions between aryl rings located on the external surfaces of equilibrating homo‐ and heterodimeric capsules. Two identical self‐complementary resorcin[4]arene tetrabenzoate molecules and one tetramethylammonium cation form in CDCl3 hydrogen‐bonded homodimeric capsules whose exteriors are decorated with four tight pairs of weakly interacting aryl rings. The pair wise mixing of six different homodimers establishes their equilibria with the corresponding heterodimeric species in which two types of aryl rings exert on each other some gentle forces. This equilibrium is significantly shifted either towards homo‐ or heterodimers depending on the nature and location of the substituents in the weakly interacting aryl rings. The thermodynamic favorability or disadvantage of the heterodimerization is determined by stronger or weaker aryl‐aryl attractions in the hetero‐ or homodimeric capsules, respectively. The four‐fold amplification of weak aryl‐aryl interactions on the external surfaces of the equilibrating capsules is responsible for high sensitiveness of our approach. [ABSTRACT FROM AUTHOR]

The assembly of MXene materials into microcapsules has drawn great attentions due to their unique properties. However, rational design and synthesis of MXene-based microcapsules with specific nanostructures at the molecular scale remains challenging. Herein, we report a strategy to synthesize N/P co-doped MXene hollow flower-like microcapsules with adjustable permeability via dual surfactants assisted hydrothermal-freeze drying method. In contrast to anionic surfactants, cationic surfactants exhibited effective electrostatic interactions with MXene nanosheets during the hydrothermal process. Manipulation of dual surfactants in hydrothermal process realized N and P co-doping of MXene to improve flexibility and promoted the generation of abundant internal cavities in flower-like microcapsules. Based on the unique microstructure, the prepared hollow flower-like microcapsules showed excellent performance, stability and reusability in size-selective release of small organic molecules. Moreover, the release rate can be controlled by turning the oxidation state and type of MXene. The strategy delineates promising prospects for the design of MXene-based microcapsules with specific structures. [ABSTRACT FROM AUTHOR]

To obtain dual functions of antibacterial and self-healing of a coating, nano-silver solution microcapsules coated with urea formaldehyde resin were selected for antibacterial agents, and rosin-modified shellac microcapsules coated with melamine formaldehyde resin were selected for repairing agents. The optical, mechanical, antibacterial, self-healing, and other physicochemical properties of the coatings were analyzed. The method of adding two microcapsules independently did not affect the coating's hardness. When the primer was prepared by self-healing microcapsules and the topcoats were prepared by antibacterial microcapsules, the hardness of the prepared coatings was maintained at 3 H, with the adhesion up to class 2, the impact strength up to 18 kg·cm, and the roughness as low as 1.144 µm. The elongation at fracture of the coatings prepared by adding microcapsules independently was improved by 2.2%. The self-healing microcapsules release the repair agents to improve the mechanical properties of the coatings. In terms of the antibacterial properties of the coatings, the method that involves adding the microcapsules independently is better than mixed adding. Against Escherichia coli, the antibacterial rate of coatings prepared by adding microcapsules independently reached 82%. Against Staphylococcus aureus, the antibacterial rate of coatings reached 83.3%. At the same time, the self-healing rate was up to 41.1%. The two microcapsules were added to the water-based coating independently to obtain antibacterial and self-healing functions with good comprehensive properties. By modifying coatings on the Andoung wood (Monopetalanthus spp.) with antibacterial microcapsules and self-healing microcapsules, it is possible to obtain good antibacterial properties, further protect the wood substrate, and broaden the application range of functional coatings. [ABSTRACT FROM AUTHOR]

Summary: Hard capsules are a frequently used oral medication delivery form. This study aims to evaluate the potential of tilapia fish gelatine as a suitable material for hard capsules, by analysing various gelatine properties under different extraction temperatures (50, 60, 70, and 80 °C) and extraction periods (6 and 12 h). The results showed a range of values for the gelatine yield (22–33% (w/w)), gel strength (141–360 g), molecular weight distribution (140–300 kDa), and amino acid composition (185–220/1000 residues). FG70‐12 (296) and FG60‐6 (266) were found to have gel strength between 200 and 300 g thus suitable to be used as hard capsule material. Interestingly, the strongest gelatine having 360 g gel strength obtained from FG50‐6 (fish gelatine extracted at 50 °C for 6 h) became the essential ingredient for preparing hard capsules because two times dipping was enough to obtain the standard weight and thickness. A slight loss of moisture was identified during drying and rapid dissolution (4–8 min) detected from fish gelatine capsule at pH 6.8 or below. Therefore, hard capsules for pharmaceutical applications could be developed from fish gelatine as an alternative gelatine with similar properties as commercial hard capsules and satisfying the pharmacopoeia standard. [ABSTRACT FROM AUTHOR]

Aerogels are a class of materials that have gained increasing attention over the past several decades due to their exceptional physical and chemical properties. These materials are highly porous, with a low density and high surface area, allowing for applications such as insulation, catalysis, and energy storage. However, traditional aerogels, such as pure silica aerogels, suffer from brittleness and fragility, which limit their usefulness in many applications. Herein, we have addressed this problem by using organosilicon compounds, namely polymethylsilsesquioxane derivatives, for the synthesis of aerogel-like materials. Specifically, we have developed a novel approach involving surfactant-free synthesis of microcapsules from partially PEGylated hyperbranched polymethylethoxysiloxane. Due to the highly diphilic nature of these compounds, they readily concentrate at the oil/water interface in aqueous emulsions encapsulating oil droplets. During the subsequent condensation, the organosilicon precursor is consumed for hexane encapsulation (yielding hollow microcapsules) followed by the formation of a continuous condensed phase. Concurrently, methyl groups ensure the hydrophobicity of the resulting materials, which eliminates the need of using additional reagents for their hydrophobization. [ABSTRACT FROM AUTHOR]

Microcapsules are small particles that can effectively protect a core material from degradation. Microcapsules with double capsule walls can improve stability and reduce breakage due to the fact that the physical and chemical properties of double-walled materials can complement each other, thus enhancing the quality and applicability of a microcapsule. Microcapsules can achieve controlled release of core materials by using a temperature-sensitive wall material. In this research, gelatin was used as the inner wall material for these double-walled microcapsules. The outer wall material was a composite material prepared by the reaction of a hydroxyl group in gum arabic with an amino group in N-isopropylacrylamide (NIPAM) in the presence of N, N'-methylene bisacrylamide (BIS), while lavender fragrance oil served as the core material. A complex coalescence method was used for the preparation of microcapsules with double capsule walls. The effects of different proportions of gum arabic to NIPAM on the core loading, microcapsule yield and thermal stability of microcapsules were studied in detail. Additionally, the stability of these fragrance microcapsules with double capsule walls in different solvents and pH values was evaluated. The sustained release properties and mechanism of cotton fabrics treated with prepared fragrance microcapsules were investigated. The results show that the microcapsules prepared with a 10:1 ratio of NIPAM to gum arabic have good temperature responsiveness. Therefore, clothing treated with microcapsules with temperature-sensitive wall materials can ensure that the human body has a fresh and pleasant smell in the case of perspiring in summer. [ABSTRACT FROM AUTHOR]

Purpose: As an efficient self-healing intelligent material, the encapsulation-based self-healing resin mineral composite (SHC) has a broad application prospect. Design/methodology/approach: Aiming at the cracking performance of SHC, the dynamic load condition is employed to replace the traditional static load condition, the initial damage of the material is considered and the triggered cracking process and influencing factors of SHC are analyzed based on the extended finite element method (XFEM). In addition, the mechanism of matrix cracking and microcapsule triggered cracking process is explained from the microscopic point of view, and the cracking performance conditions of SHC are studied. On this basis, the response surface regression analysis method is used to obtain a second-order polynomial model of the microcapsule crack initiation stress, the interface bonding strength and the matching relationship between elastic modulus. Therefore, the model could be used to predict the cracking performance parameters of the microcapsule. Findings: The interfacial bonding strength has an essential effect on the triggered cracking of the microcapsule. In order to ensure that the microcapsule can be triggered cracking normally, the design strength should meet the following relationship, that is crack initiation stress of microcapsule wall < crack initiation stress of matrix < interface bonding strength. Moreover, the matching relationship between elastic modulus has a significant influence on the triggered cracking of the microcapsule. Originality/value: The results provide a theoretical basis for further oriented designing of the cracking performance of microcapsules. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The design of porous microcapsules with selective mass transfer and mechanical robustness for enzyme encapsulation is highly desired for biocatalysis, yet the construction remains challenging. Herein, we report the facile fabrication of porous microcapsules by assembling covalent organic framework (COF) spheres at the interfaces of emulsion droplets followed by interparticle crosslinking. The COF microcapsules could offer an enclosed aqueous environment for enzymes, with size‐selective porous shells that allow for the fast diffusion of substrates and products while excluding larger molecules such as protease. Crosslinking of COF spheres not only enhances the structural stability of capsules but also imparts enrichment effects. The enzymes encased in the COF microcapsules show enhanced activity and durability in organic media as verified in both batch reaction and continuous‐flow reaction. The COF microcapsules offer a promising platform for the encapsulation of biomacromolecules. [ABSTRACT FROM AUTHOR]

The colloidal dispersion in a nonpolar medium is an essential material for electrophoretic displays (EPD) with low‐power consumption. A uniform‐sized superparamagnetic iron oxide nanoparticle (SPION) is a promising candidate for EPD, which exhibits tunable structural color by Bragg diffraction. In this study, the surface of SPION is charged in a nonpolar medium by inverse micelles of Solsperse‐17k, an oil‐soluble polymeric surfactant. A photonic ink of SPION dispersion exhibits simultaneous magnetochromism and electrochromism. The photonic ink is encapsulated via a complex coacervation process, in which double layers of gelatin/gum Arabic form a stable shell for µ‐capsule. The µ‐capsules show tunable structural colors, which depends upon the size of SPION in photonic ink. The increased surfactant content in photonic ink brings about a decrease in µ‐capsule size due to a reduced surface tension. A lowered gelatin concentration during coacervation results in a smaller µ‐capsule, which exhibits an electrical color tunability. Optical characterization using a confocal microscopy enables 3D visualization of the inner structure of µ‐capsules and the formation of particle chain structure of SPION in H‐field. The encapsulated photonic ink exhibits magnetochromism for 1 year, illuminating the long‐term stability of µ‐capsules developed in this study. [ABSTRACT FROM AUTHOR]

In this paper, a chitosan-modified nano-silver solution was used as the core material of an antibacterial agent, and melamine formaldehyde resin was coated onto the core material to obtain the antibacterial microcapsules. The core/wall ratio, the stirring rate, the mass ratio of chitosan to silver ions, and the concentration of the emulsifier were used to carry out four-factor and three-level orthogonal experiments to explore the most significant factors affecting the coverage rate and output of microcapsules and the best preparation technology. The results showed that the concentration of the emulsifier was the most important factor affecting the preparation of microcapsules. The higher the concentration of the emulsifier, the better the dispersed morphology of microcapsules, and the higher the coverage rate, up to 44.0%. The antibacterial coating was prepared by mixing microcapsules with a waterborne primer at a content of 4.0%. Its optical properties, mechanical properties, and antibacterial properties were analyzed. By increasing the concentration of the emulsifier, the gloss of the coating showed a trend of first increasing and then decreasing. When the emulsifier concentration was 2.0%, the gloss of the Andoung wood surface coating reached the maximum value of 21.23%. The influence of emulsifier concentration on the color difference of coating had no obvious law, and it was negatively related to the light transmittance. In terms of mechanical properties, the concentration of the emulsifier is directly proportional to the hardness and impact resistance of the coating, with the maximum reaching 31 kg·cm, and is negatively related to adhesion and roughness. In terms of antibacterial properties, the higher the concentration of the emulsifier, the better the antibacterial properties of the coating. When the concentration of the emulsifier was 4.0%, the antibacterial rates of coating which coated the glass substrate were 71.3% and 80.0% for Escherichia coli and Staphylococcus aureus, respectively. The antibacterial rates of the Andoung wood surface coating reached the maximum, which were 68.4% and 73.2%, respectively, and the antibacterial performance was excellent. In this study, an efficient antibacterial microcapsule for waterborne coatings was prepared, which provided the reference value for the application of antibacterial microcapsules in waterborne coatings. [ABSTRACT FROM AUTHOR]

The release rate of liquid core material from microcapsules is crucial for the surface properties of self-protective metal/liquid microcapsule composite plating coating. However, there is no method to accurately predict the release rate of microcapsules. In this paper, the permeability experiments of different shell membranes and core materials were carried out using the weight loss method, and the permeability model of liquid microcapsules was studied based on a multiple linear regression method. The results show that three-variable mathematical model C, including membrane porosity, the viscosity of core material, and membrane thickness is suitable to describe permeability, and the membrane thickness is the most significant influence factor. Additionally, the accuracy of model C was experimentally verified, and the error of the permeation rate is about 2.06% between predictive and experimental values. [ABSTRACT FROM AUTHOR]

Objective: Hydroxypropyl-β-cyclodextrin (HP-β-CD)/menthyl acetate (MA) microcapsules were developed to overcome the volatile and unstable defects of MA and improve the ease of use and storage. Methods: MA microcapsules were prepared via spray drying using HP-β-CD as the wall material. The embedding rate of MA microcapsules was determined through gas chromatography. The embedding characteristics were studied using phase solubility and nuclear magnetic resonance (NMR). The stability was characterized via differential scanning calorimetry (DSC) and the release and retention rates of MA microcapsules at different temperatures. Results: The embedding rate of HP-β-CD /MA microcapsules was 96.3%. The Gibbs free energy change, enthalpy change and entropy change of the embedding reaction between HP-β-CD and MA were all less than zero, indicating that the embedding process was a spontaneous exothermic reaction. NMR spectra showed that MA entered the cavity of HP-β-CD through the large opening end and interacted with the inner wall of the small opening end. DSC and the release and retention rates of MA microcapsules at different temperatures showed that the stability of MA was significantly enhanced after being embedded in HP-β-CD. Conclusion: The HP-β-CD/MA microcapsules are able to significantly improve the stability of MA and reduce the volatilization of MA. [ABSTRACT FROM AUTHOR]

In this study, the antibacterial microcapsules of cinnamon essential oil (CEO) were prepared by complex condensation method. Chitosan quaternary ammonium salt (HACC) combined with gum arabic (GA) was selected as the coated wall material. The optimal preparation conditions of CEO microcapsules (CMSs) were determined by response surface methodology (RSM): the core/wall mass ratio was 1:1, the pH value was 4.5, the mass concentration of CaCl2 was 0.7 wt% and the actual encapsulation rate of microcapsules was 90.72% ± 1.89%. The morphology, size, composition and thermal stability of the prepared CMSs were characterized by scanning electron microscopy (SEM), laser particle size analysis (LPDA), Fourier transform infrared spectroscopy (FTIR), thermogravimetric differential thermal analysis (TG–DTA) and differential scanning calorimetry (DSC). In addition, the in vitro drug release and antibacterial properties of CMS were also evaluated. The results showed that CMS was spherical, with an average particle size of 6.31 µm. The obvious weight loss occurred at 269 °C and the corresponding DSC curve had an obvious exothermic peak at 265.5 °C, which had an increase compared with CEO. Microcapsules can achieve slow release, with the lowest and highest release rates being 19.66% and 49.79%, within 30 days. The drug release curve of essential oil of microcapsules was consistent with a first-order release model named ExpDec1. Based on the above research results, the CMS can effectively improve the stability of essential oil, achieve slow release and prolong the antibacterial effect, indicating its potential applications in food, cosmetics and medicine. [ABSTRACT FROM AUTHOR]

Magnetic carbonyl iron powder (CIP) microcapsules were created by in situ polymerization using melamine resin as the wall material and CIP as the core material. They were mixed with shellac self-repairing microcapsules to prepare dual-functional wood coatings, and the effect of different amounts of CIP microcapsules in the Dulux Waterborne primer on the performance of the primer was investigated. The findings demonstrated that the core-wall ratio had a significant impact on the characteristics of CIP microcapsules. The microcapsule coating rate reached 57.7% when the core-wall ratio was 0.65:1. The maximum reflection loss of CIP microcapsules with the core-wall ratio of 0.70:1 is −10.53 dB. When the addition amount of shellac self-repairing microcapsules is 4.2%, and the additional amount of CIP microcapsules with a core wall ratio of 0.65:1 and 0.70:1 is 3.0%, the coating color difference is the smallest. The number of microcapsules causes a noticeable drop in the coating's gloss, and the amount of microcapsules causes a small negative change in the coating's adherence. With an increase in the number of microcapsules, the coating's hardness, impact resistance, and tensile resistance first rose and subsequently fell. When the content of CIP microcapsules with core-wall ratio of 0.65:1 and 0.70:1 was 9.0%, the hardness, elongation at break and repair rate of the coating reached the best performance. According to a comprehensive analysis, when the content of CIP microcapsules with core-wall ratio of 0.70:1 is 9.0%, the coating has good performance. At this time, the coating has a color difference of 1.83, a glossiness of 19.3, an adhesion of 2 H, a hardness of 3 H, an impact resistance of 17 kg·cm, and a repair rate of 33.3%. This provides a technical basis for the application of multifunctional coatings on wooden substrates. [ABSTRACT FROM AUTHOR]

We have shown in a previous work that the combination of the emulsion solvent evaporation technique and droplet-based microfluidics allows for the synthesis of well-defined monodisperse mesoporous silica microcapsules (hollow microspheres), whose size, shape and composition may be finely and easily controlled. In this study, we focus on the crucial role played by the popular Pluronic® P123 surfactant, used for controlling the mesoporosity of synthesised silica microparticles. We show in particular, that although both types of initial precursor droplets, prepared with and without P123 meso-structuring agent, namely P123+ and P123− droplets, have a similar diameter (≃30 μm) and a similar TEOS silica precursor concentration (0.34 M), the resulting microparticles exhibit two noticeably different sizes and mass densities. Namely, 10 μm and 0.55 g/cm3 for P123+ microparticles, and 5.2 μm and 1.4 g/cm3 for P123− microparticles. To explain such differences, we used optical and scanning electron microscopies, small-angle X-ray diffraction and BET measurements to analyse structural properties of both types of microparticles and show that in the absence of Pluronic molecules, P123− microdroplets divide during their condensation process, on average, into three smaller droplets before condensing into silica solid microspheres with a smaller size and a higher mass density than those obtained in the presence of P123 surfactant molecules. Based on these results and on condensation kinetics analysis, we also propose an original mechanism for the formation of silica microspheres in the presence and in the absence of the meso-structuring and pore-forming P123 molecules. [ABSTRACT FROM AUTHOR]

With the development of science and technology, the function of waterborne coatings has been advanced to a higher standard, which requires researchers to innovate and expand the research on them. Aloe-emodin is a natural material with antibacterial properties. Applying its antibacterial effect to the coating can enrich its function and meet the diversified needs of consumers. In this study, the urea-formaldehyde resin was used as the wall material and the aloe-emodin as the core material to prepare the microcapsules. The coating rate, yield, and morphology of the microcapsules were characterized. Through an orthogonal experiment and a single factor experiment, the optimization scheme of microcapsule preparation was explored. The results indicated that the optimum preparation process of aloe-emodin microcapsules was as follows: the mass ratio of core material to wall material was 1:15, the molar ratio of urea to formaldehyde was 1:1.2, the temperature of microencapsulation was 50 °C, and the stirring speed of microencapsulation was 600 rpm. On this basis, the aloe-emodin microcapsules with 0%, 1.0%, 3.0%, 6.0%, 9.0%, and 12.0% contents were added to the waterborne coating to prepare the paint films, and their influence on the antibacterial and optical properties of the waterborne paint films was explored. The results demonstrated that the aloe-emodin microcapsules had antibacterial activity. When the content was 6.0%, the comprehensive performance of the film was better. The antibacterial rate of the film against Escherichia coli was 68.1%, and against Staphylococcus aureus it was 60.7%. The color difference of the film was 59.93, and the glossiness at 60° was 7.8%. In this study, the microcapsules that can improve the antibacterial performance of water-based coatings were prepared, which can expand the application of water-based coatings and provide a reference for the study of the functionalization of water-based coatings. [ABSTRACT FROM AUTHOR]

In this paper, nanosilver solution was used as an antibacterial agent to prepare antibacterial microcapsules. The mass ratio of the core material to the wall material (Wcore: Wwall), the emulsifier's hydrophilic–lipophilic balance (HLB) value, the mass ratio of ethanol to the emulsifier in solvent (Wcore: Wemulsion), and the rotational speed (r/min) were used to develop the four-factor, three-level orthogonal experiment, which was meant to investigate the most significant factors and the optimum process preparation parameters impacting the coating rate and yield of microcapsules. It was used to make an antibacterial coating that was applied to the surface paint film of a glass substrate and andoung wood, and it was mixed to the water-based primer with a content of 4%. Analyses of the mechanical, optical, and bactericidal characteristics were conducted. The micromorphology of the nanosilver solution microcapsules is influenced by the emulsifier's HLB value. The color difference of the antibacterial coating film decreased with increasing emulsifier HLB value; however, the coating film's gloss remained largely suitable. Additionally, the coating film's transparency and tensile strength both decreased. It had minimal impact on the paint film's surface hardness, but the adhesion and tensile strength showed a noticeable downward trend. The surface of the paint film was rough. Escherichia coli and Staphylococcus aureus were resistant to the antibacterial characteristics of the water-based primer film when it was combined with antibacterial nanosilver solution microcapsules by 80.7% and 74.55%, respectively. The coating film's antibacterial properties were applied to the surface of the andoung wood, which were 75.7% and 71.0%, respectively, and somewhat decreased. In order to successfully inhibit bacteria, the nanosilver solution microcapsules were added to waterborne coatings. This ensures both the outstanding performance of the coating film and the effectiveness of the antibacterial effect. It expands the application prospects of antibacterial microcapsules in coatings. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glucoamylase was often used in the brewing industry but was unstable to several environmental factors and reacted quickly to produce fermentable sugar, which limited its applications. Microencapsulation could effectively overcome the drawbacks. This study evaluated the feasibility of the preparation of glucoamylase microcapsules (GM) using W/O/W complex coacervation‐freeze‐drying method. The parameters of the microcapsules were optimized by the response surface optimization design: core‐wall ratio at 1:1, wall‐material concentration at 8%, and coagulation time for 20 min. Under current condition, the final microencapsulation efficiency reached 85.64 ± 1.60%. Glucoamylase could be slowly released for more than 96 h in the liquid state, and could react slowly for more than 336 h in the solid state. The optimized GM were incubated for 1 h, and the relative enzyme activity was better than that of free glucoamylase under high temperature conditions. The water capacity, solubility, morphology, differential scanning calorimetry, and Fourier transform infrared spectroscopy were conducted. Glucoamylase exhibited good sustained release characteristics. The microcapsules were more resistant to environmental stimuli and showed stronger robustness after optimization. Practical Application: Saccharification enzymes are often used in the winemaking industry, and direct addition will cause the fermentation process to heat up too quickly, resulting in the inactivation of microorganisms and saccharification enzymes, affecting the efficiency of saccharification enzymes. Therefore, microcapsules are used to encapsulate the saccharification enzyme, and its efficacy is slowly released for a long time during the fermentation process. [ABSTRACT FROM AUTHOR]

Two‐ and three‐phase molecular encapsulations of Me4N+ or C7H7+ in the hydrogen‐bonded dimers of resorcin[4]arene tetraphosphates enable ion pair separations, dissolution of solid capsule components, and stabilization of capsule‐separated ion pairs in solution. Self‐assembly of the capsular ion pairs, the exchange of the encapsulated cations and external anions as well as the formation of heterodimeric capsular complexes are slow on hours time scale in heterogeneous systems and instantaneous in solutions. Spectroscopic studies and molecular modeling related the properties of the capsule‐separated ion pairs to the energies of induced conformational changes, hydrogen bonding, host‐guest interactions, ion pair separation, and the relative polarity of the solvent. [ABSTRACT FROM AUTHOR]

Background and objective: Vitamin D is a fat soluble nutrient which was help to improve human health. There are different problems in VD3 fortification of foods including low water solubility and susceptibility to environmental conditions. Microencapsulation of VD3 could be used to overcome these limitations. Encapsulation of VD3 in yeast cells can be counted as an affective technique to provide a protection against VD3-photochemical degradation. Material and methods: In this study, VD3 was encapsulated in Saccharomyces cerevisiae yeast cells as encapsulating matrix. Microcapsules were dried by spray drier and freeze drier. Two concentration of vitamin (100 and 500 IU) used for bread fortification. Furthermore, the effect of UV irradiation and thermal treatment (80 °C for 1 minutes) on stability of free and encapsulated vitamin D was investigated. Results and conclusion: The results showed, about 40% and 95% of vitamin were remained after application of UV and high temperature treatment, respectively. In addition, yeast cells could provide good protection against (more than 95%) high temperature of bread baking process (180 °C for 30min). The analysis of bread quality and sensory properties showed higher value of bread containing encapsulated VD3 in comparison to free form. The results of this study show that the Saccharomyces cerevisiae yeast cell could be used as a suitable carrier for encapsulation of VD3. [ABSTRACT FROM AUTHOR]

[Display omitted] Biocatalytic reaction networks in eukaryotic cells is realized by the immobilized and compartmental multi-enzymatic system. Inspired by the spatial localization of natural cells, multiple enzymes were confined within the multicompartmental microcapsules, which were created using a gas-shearing method coupled with surface-triggered in situ gelation strategy. Heterogeneous multicompartmental (two-, three-, four-, six-, or eight-faced) core particles, due to their capacity for positional assembly, were encapsuled in alginate hydrogel shells. The generated microcapsules integrate logic network to access complex digital design through a three-step convergent enzymatic cascade reaction as a model, and the capsules with high stability, recyclability and cytocompatibility are ideal enzymatic reactor systems to be used for biomimetic biocatalysis process. [ABSTRACT FROM AUTHOR]

Lipid oxidation products can affect the molecular structure and digestibility of peanut protein isolates. Lipid‐oxidizing systems (LOS) is a simulation system which uses oxygen‐free radicals generated by the reaction of linoleic acid and lipoxygenase as oxidants.The simulation system was established to mediate oxidation of arachin or conarachin. Degree of oxidation (DOX) of peanut protein isolates (PPIs) was measured as quantity of LA to generate LOS. This study analyzed the effect of lipid oxidation‐derived free radicals on the molecular structure and digestive properties of arachin and conarachin and observed substantial changes in carbonyl content, total sulfhydryl content, and number of disulfide bonds as quantities of LA increased, thus indicating significant oxidation of two proteins. Further, it was found that arachin was more stable than conarachin in a LOX‐catalyzed oxidizing system. When the amount of LA was 3 and 5 ml, the maximum surface hydrophobic characteristic values of arachin and conarachin reached the maximum, which were 235 ± 10 and 349 ± 13, respectively. This study laid a theoretical foundation for the application of peanut protein in food products. Practical applications: peanut protein has generated interest because it is the best source for the wall material for the preparation of nanoparticles and microcapsule particles due to its good biocompatibility and biodegradability, The structure‐activity relationship between arachin and conarachin is of great guiding significance for the improvement of peanut protein molecular modification and functional properties.This study laid a theoretical foundation for the application of peanut protein in food products. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) has been identified by many researchers as one of the cost-effective solutions for not only storing excess or/wasted energy, but also improving systems' reliability and thermal efficiency. Among TES, phase change materials (PCMs) are gaining more attention due to their ability to store a reasonably large quantity of heat within small temperature differences. Encapsulation is the cornerstone in expanding the applicability of the PCMs. Microencapsulation is a proven, viable method for containment and retention of PCMs in tiny shells. Currently, there are numerous methods available for synthesis of mPCMs, each of which has its own advantages and limitations. This review aims to discuss, up to date, the different manufacturing approaches to preparing PCM microcapsules (mPCMs). The review also highlights the different potential approaches used for the enhancement of their thermophysical properties, including heat transfer enhancement, supercooling suppression, and shell mechanical strength. This article will help researchers and end users to better understand the current microencapsulation technologies and provide critical guidance for selecting the proper synthesis method and materials based on the required final product specifications. [ABSTRACT FROM AUTHOR]

Microcapsules have received a great deal of attention from researchers due to their excellent properties, and are commonly prepared by interfacial and in situ polymerisation methods. In situ polymerisation is an important method of microcapsule preparation, which has a number of advantages such as low cost and suitability for industrial production. Microencapsulation is used to modify the state of the material in order to improve its practical usability and mechanical and optical properties. In this paper, urea–formaldehyde resin–coated colour–changing powder microcapsules were prepared and their properties were used to study the colour–changing properties of wood surface coatings, and the mechanical and optical properties of waterborne paint films incorporating colour–changing powder microcapsules were tested. The results show that as the microcapsule content increases, the colour–change effect of the coating gradually becomes obvious and the amount of change in the b–value representing the yellow hue gradually increases. As the microcapsule content increased from 1.0% to 13.0%, the b–value increased from 0.7 to 2.6. The gloss of the film decreased significantly with the increase in the microcapsule content of the colour–change powder, with the highest gloss at 1.0%. The impact resistance of the film was also influenced by the content of microcapsules in the waterborne topcoat, with the best impact resistance at 5.0%, level 2 of adhesion at 1.0%–5.0% and 11.0%–13.0%, and level 1 of adhesion at 7.0% and 9.0%. In terms of mechanical and optical properties, the 5.0% content of colour–changing powder microcapsules is the best for the overall performance of waterborne topcoats. In practical furniture applications, the microcapsules prepared in this paper can change the colour in appearance according to the actual temperature and play a decorative role. [ABSTRACT FROM AUTHOR]

In water-based coatings, the addition of tung oil microcapsules coated with urea formaldehyde resin (UF) can effectively repair the microcracks in the coating film on the surface of wood. The tung oil as a repairing agent plays an important role in the preparation of microcapsules. In this paper, Span-80, SDBS, OP-10, Tween-80 and SDS were used as five emulsifiers to study the influence of different emulsifiers on the preparation of tung oil microcapsules, and the properties of the coating film added to the waterborne coatings. According to the coating process of three bottoms and three sides, tung oil microcapsules were added to the water-based paint with a content of 12% and coated on the wood surface. The appearance and microstructure of the microcapsules, as well as the mechanical, optical and self-repairing properties of the paint film were analyzed to find out the best emulsifier suitable for the core material. The tung oil microcapsules prepared by Tween-80 have the best morphology, concentrated particle size distribution, particle size of 6–15 μm, and spherical morphology. The film with the microcapsules prepared by Tween-80 had the best performance, small color difference, high gloss, hardness of 5H, adhesion grade 1, elongation at break of 47.23%, impact resistance of 20 kg∙cm, and good toughness. At the same time, the repair rate reached 37.9%. The results provide the application reference for the use of self-repairing microcapsules in coatings. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spirulina (Artrhospira platensis) is rich in chlorophylls (CH) and is used as a potential natural additive in the food industry. In this study, the CH content was extracted from spirulina powder after ultrasound treatment. Microcapsules were then prepared at different ratios of gum Arabic (GA) and whey protein isolate (WPI) through freeze-drying to improve the chemical stability of CH. As a result, a* and C* values of the microcapsules prepared from GA:WPI ratios (3:7) were −8.94 ± 0.05 and 15.44 ± 0.08, respectively. The GA fraction increased from 1 to 9, and encapsulation efficiency (EE) of microcapsules also increased by 9.62%. Moreover, the absorption peaks of CH at 2927 and 1626 cm−1 in microcapsules emerged as a redshift detected by FT-IR. From SEM images, the morphology of microcapsules changed from broken glassy to irregular porous flake-like structures when the GA ratio increased. In addition, the coated microcapsules (GA:WPI = 3:7) showed the highest DPPH free radical scavenging activity (SADPPH) (56.38 ± 0.19) due to low moisture content and better chemical stability through thermogravimetric analysis (TGA). Conclusively, GA and WPI coacervates as the wall material may improve the stability of CH extracted from spirulina. [ABSTRACT FROM AUTHOR]

The present paper reports a continuous microfluidic approach for the preparation of microcapsules (MCs), by interfacial polymerization, with a polyurea/polyurethane (PUa/PU) shell containing isophorone diisocyanate (IPDI). The microfluidic system enables the formation of a monodisperse oil-in-water (O/W) emulsion by a separate flow of the reagents along the tubing system, which posteriorly meet at a cross-junction, resulting in the precise formation of one emulsion droplet at a time. The developed MCs are intended to be part of a new monocomponent, autoreactive and ecological adhesive, as cross-linking agents. Critical operational parameters in the microfluidic process were investigated, namely the flow rate of the emulsion phases, the cross-junction's configuration and its correlation with the MCs' morphology, average diameter, size distribution and amount of encapsulated isocyanate. The advances achieved in the current study represent a contribution to the development of new sustainable and eco-friendly products, where the employment of monodisperse MCs is an advantage. [ABSTRACT FROM AUTHOR]

Eggshells are rich in Ca2+ and organic compounds, which can be taken as coupling agents for sustained-release materials. Essential oils are widely applied due to their excellent volatility, but poor sustained-release stability has limited their development. The study aimed to develop a novel eggshell powder (EP) sustained-release microcapsule, providing a new approach to protect the active ingredients of Lavender essential oil (LEO), and investigated the reasons for EP to regulate protein-polysaccharide microcapsule structure. Experimental results showed when the addition ratio of EP and Whey protein (WPI) was 1: 3, the dosage of LEO was 25%, the microcapsule displayed smooth and porous spherical structure. XRD and FT-IR indicated that a dense and orderly network structure was formed via the cross-linking reaction between eggshell powder and wall materials, which induced protein and polysaccharide to form special spherical hollow sustained-release shell structure through the calcium bridge (-COO-Ca-COO-), then achieved the sustained-release effect on LEO. [Display omitted] • EP-WPI microcapsules with smooth and porous surface were prepared by spray drying. • EP significantly enhanced the sustained-release properties of microcapsules on LEO. • Microcapsules with EP improved the antioxidant capacity of LEO. • The potential application value of EP microcapsules in industry filed was revealed. [ABSTRACT FROM AUTHOR]

• Limit interfacial reactant diffusion by sharp interface engineering. • Form a robust viscoelastic film around emulsions by copolymer self-assembly. • Gentler shell-formation kinetics and strengthened films enhance microencapsulation. • The two-step one-pot method yields microcapsules with tunable properties. • The adjustability of amine microcapsules boosts uses as CO 2 absorbents and adhesives. Microencapsulation of hydrophilic amines in nonaqueous emulsions provides opportunities for a variety of applications, such as CO 2 absorbents, and adhesives, but also presents challenges due to the intense reactant diffusion and disruptive interfacial reaction kinetics. Drawing inspiration from cellular systems, where cell membranes effectively regulate mass transfer for essential activities, we propose an interface engineering approach to manage interfacial reactant diffusion. This strategy obviates the modification of emulsion phases with additives in literature, which lowered effective core content. To achieve this, a solvent-induced polymer self-assembling method is adopted. The self-assembled polymer effectively formed a stabilizing viscoelastic film, which kinetically traps the microdroplets, serves as a viscous barrier lowering intense amine diffusion and interfacial polymerization kinetics, and provides protection for the microdroplets against the destructive forces from reaction turbulence and emulsion collision. This approach possesses high tolerance against microencapsulation conditions and is technically friendly, laying the groundwork for scalable microencapsulation of amines to meet industrial demands. We successfully synthesized Tetraethylenepentamine (TEPA)-loaded microcapsules with adjustable shell tightness, hierarchical shell structures, high shell strength and high core content. The method's versatility is further evidenced with different species containing reactive hydrogens. The demonstrated potential of TEPA-loaded microcapsules in effective CO 2 capture and instant adhesives provides a fresh perspective on the microencapsulation of distinct polar payloads through interface engineering and its wide-ranging applications. [ABSTRACT FROM AUTHOR]

In this study, we developed a sodium alginate gel bead (Sbs-Mcs-Cur) encapsulating curcumin microcapsules (Mcs-Cur) to protect the bioaccessibility of curcumin in the gastrointestinal tract and enhance its edible efficiency. Structural characterization indicated that curcumin was successfully encapsulated in Sbs-Mcs-Cur. Antioxidant capacity experiments demonstrated that Sbs-Mcs-Cur successfully eliminated over 90% of DPPH and ABTS free radicals. The release behavior of Sbs-Mcs-Cur was evaluated using a simulated gastrointestinal model. Release rate in vitro measurements showed that Sbs-Mcs-Cur had a low release rate (<0.5%) in simulated gastric fluid (SGF), while more than 97.2% were released in simulated intestinal fluid (SIF), indicating that Sbs-Mcs-Cur could mitigate inhibition of microcapsule solubilization caused by the gastric environment, and effectively enhancing the release rate of curcumin in the intestine. These present findings demonstrated that the sodium alginate hydrogel system equipped with gum Arabic/gelatin microcapsules could be used as an ideal carrier for delivering hydrophobic bioactive substances like curcumin in functional food systems. [Display omitted] • Preparation of sodium alginate gel beads equipped with curcumin microcapsules. • Structures of microcapsules and gel beads are clearly characterized. • Gel beads with excellent radical scavenging and gastric erosion resistance. • The release of curcumin is dominated by the super case Ⅱ mediated mechanism. [ABSTRACT FROM AUTHOR]

This study prepared a new type of electrophoretic display microcapsule with flexibility and strength, namely gum arabic/gelatin/urea-formaldehyde resin microcapsule, based on polysaccharides as the reaction starting point, combined with proteins and resins. The composition, morphology and thermal stability of the microcapsules were tested by Fourier transform infrared spectroscopy, stereo fluorescence microscopy, scanning electron microscopy and thermogravimetric analysis. It was found that the morphology and stability of the new microcapsules prepared by the method are better than those prepared by the traditional complex coacervation method or the in-situ polymerization method. At the same time, it showed that the rotational speed was between 1000 rpm and 1200 rpm, the concentrations of gum arabic and gelatin were 3 wt%, the reaction pH between 3 and 3.5, the reaction duration is between 150 min and 180 min, the ammonium chloride was 20 wt%, and resorcinol was 6 wt%, the reaction between the urea-formaldehyde prepolymer and the electro-neutralizer formed by gelatin and gum arabic was sufficient, the microcapsule wall structure was uniform and consistent, with a dense resin based structure on the outer layer and a flexible blend structure inside. [Display omitted] • By physical and chemical reaction, three different types of organic compounds, gum arabic, gelatin and urea-formaldehyde resin, were synthesized into flexible electrophoresis microcapsules with good performance, low production cost and environmental friendliness. • Aldehydes in urea formaldehyde prepolymers act as crosslinking agents to organically bind gum arabic and gelatin with different charges. At the same time, urea formaldehyde prepolymer self polymerizes under acidic conditions to form urea formaldehyde resin, which uniformly deposits on the surface of microcapsules, playing a reinforcing role. • Compared with microcapsules prepared by traditional complex coagulation and in-situ polymerization methods, the new microcapsules have better transparency, stability, and mechanical strength. • The new microcapsules have been applied in laboratory electrophoresis display experiments. The microcapsules are stable under an electric field and can observe the movement of electrophoresis particles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A simple preparation of inorganic reinforced poly(ionic liquid) (PIL) microcapsules by combining dispersion polymerization and confined cooling‐assisted phase separation self‐assembly is reported. Silane coupling agent‐modified PIL microbeads are first prepared by dispersion polymerization. Then, the microbeads are dissolved in a theta solvent composed of good solvent and non‐solvent to form hollow SiOx microcapsules at a relatively high temperature. Finally, the solution is cooled to induce the nucleation and growth of dissolved PIL chains on the inner and outer surface of hollow SiOx microcapsules to form inorganic reinforced microcapsules with asymmetric PIL/SiOx/PIL sandwich‐like shell. The morphology of microcapsules can be controlled by adjusting PIL concentration and cooling rate. The inorganic reinforced microcapsules show enhanced suspended stability and electroresponsive characteristic when used as the dispersed phase of smart suspensions. [ABSTRACT FROM AUTHOR]

This study aims to develop microcapsules that can be used as room‐temperature self‐healing agents in silicone‐based matrices. A telechelic reactive silanol‐terminated polydimethylsiloxane (PDMS) as the healing agent, was selected to ensure the homogeneity of the polymeric matrix and encapsulated in poly(melamine‐urea‐formaldehyde) shells through an in‐situ emulsion polymerization technique. To catalyze the polycondensation reaction of the healing agent, dibutyltin dilaurate (DBTL) was encapsulated within the same type of polymeric shell. The synthesized microcapsules were characterized using Fourier‐transform infrared spectrometry, optical microscopy, scanning electron microscopy (SEM), and differential scanning calorimetry. The analyses confirmed that the spherical microcapsules with an average size of 56 μm for PDMS‐MUF microcapsules and 42 μm for DBTL‐MUF microcapsules, with a shell wall thickness of 100–200 nm, and good thermal stability were formed. Therefore, the two‐component self‐healing silicone composite was successfully developed using 10:1.2 wt% PDMS: DBTL microcapsules within the silicone matrix. SEM showed the self‐healing ability of the silicone matrix by observing the successful healing of microcracks at room temperature. Tensile and trouser tear tests were adopted to assess the self‐healing performance of the elastomeric matrix, showing the self‐healing efficiencies of 67% and 55%, respectively. [ABSTRACT FROM AUTHOR]

A novel in situ polymerization and imidization method is adopted to synthesize Si‐based microcapsule materials with polyimide shell. As a mechanically stable polymer, polyimide microcapsule shell can effectively alleviate the volume effect of silicon nanoparticles during alloying/de‐alloying reactions, stabilize the electrode construction, suppress the serious side reactions of electrolyte components on silicon anode surface, and help to form a flexible, homogeneous and low‐resistance solid electrolyte interphase (SEI). In addition, the conjugated carbonyl groups of polyimide make it Li+‐conductive and electrochemically active, thus increasing the electrochemical activity of silicon anode. The as‐prepared Si@polyimide microcapsules manifest high initial coulombic efficiency of 91.1 %, high initial discharge capacity of 2798.7 mA h g−1 at 210 mA g−1 (0.05 C), good rate behavior with a capacity of 1954 mA h g−1 at 10 C current rate, and considerably improved cycling performance preserving a capacity of 1239.9 mA h g−1 at 4.2 A g−1 (1 C) after 300 cycles. [ABSTRACT FROM AUTHOR]

In this study, the pyraclostrobin@polydopamine-polyurea microcapsules (Pyr@PNPMC) with anti-photolysis and sustained-release properties were prepared by interfacial polymerization based on O/W Pickering emulsion templates. The effects of water–oil ratio, stirring speed, temperature, and polydopamine nanoparticles (PDANPs) content on the preparation of microcapsules were systematically investigated. Under this condition, the encapsulation efficiency of microcapsules could reach up to 77.7%. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) images indicated that Pyr@PNPMC were prepared successfully, and the microcapsules were a regular sphere with a large number of PDANPs attached to the dense inner layer. According to the results of sustained-release and anti-photolysis experiments, the release rate of Pyr@PNPMC was slightly faster than that of the pyraclostrobin@polyurea microcapsules (Pyr@MC). Under UV light exposure for 7 h, Pyr@PNPMC still retains 83% of the active ingredient, while for Pyr@MC nearly 75% of the active ingredient had been lost. [ABSTRACT FROM AUTHOR]

Octyl methoxycinnamate and butyl methoxydibenzoylmethane are organic UV filters with poor photostability and will become photoallergy or phototoxic substance when exposed to ultraviolet radiation. The organic UV filters coated by microcapsules can reduce the photodegradation and avoid direct contact with the skin. Through microencapsulation, the application of UV filters in cosmetics becomes more effective and safer. This study first used the sol-gel method to create organic/inorganic composite UV filter microcapsules. We used sodium alginate as a shell material of the microcapsule to encapsulate UV filters. CaCO3 and tetraethyl orthosilicate (TEOS) were used as cross-linking agents, and sorbitan monooleate (Span 80) and polyoxyethylenesorbitan monooleate (Tween 80) were used as emulsifiers in the interfacial polymerization method for preparation. The results indicated that the microcapsules with 3 g of CaCO3 cross-linking agents had a similar particle size and better entrapment efficiency. The average sizes were 61.0 ± 4.9 μm and 48.6 ± 4.7 μm, and entrapment efficiencies were 75.3 ± 1.9% and 74.8 ± 1.7% for octyl methoxycinnamate and butyl methoxydibenzoylmethane, respectively. Utilizing sodium alginate as a cross-linking agent is better than TEOS due to the higher calcium content. In vitro transdermal delivery analysis showed that the release rate became steady. [ABSTRACT FROM AUTHOR]

Summary: Umami has a fast release in the long time high temperature cooking process. Microencapsulation technology can be used to control the release of aromas, and spray drying is the method most commonly used for preparing microcapsules. In this study, the Maillard reaction products from the enzymatic hydrolysate of the Aloididae aloidi were combined with chitosan (C); maltodextrin (M); chitosan and gum arabic (C + GA); M + GA; and C + M + GA via spray drying. Characterisation, flavour characteristics and umami release of microcapsules were analysed and determined. The results showed that the obtained microcapsules had the characteristics of low water content and high solubility, and had good embedding effect and thermal stability (especially MC + GA). Scanning electron microscopy results showed that the addition of wall material increased the diameter of the particles. The microcapsules in MC group and MC + GA group showed the best apparent structure, which was round without pits or pores. In the controlled release study of umami, MC + GA group showed the best sustained umami release, released 13.95%, 38.08% and 80% umami at 0.5, 4 and 32 min, respectively. In conclusion, adding C + GA as wall material of microcapsules had the best stability, flavour and taste sustained‐release effect. [ABSTRACT FROM AUTHOR]

In this paper, the interface polymerization method was used to prepare Osmanthus essential oil microcapsules. The optimal preparation process of Osmanthus essential oil microcapsules was explored as follows: the dosage ratio of Osmanthus essential oil to N100 was 6:1, the reaction temperature was 70°C, and the reaction time was 2 h. The encapsulation efficiency of Osmanthus essential oil microcapsules could reach 80.31%. The particle size distribution, morphology, chemical structure, and thermal stability of the obtained microcapsules were characterized by laser particle size analyzer, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The release kinetics and storage stability experiments of the microcapsules were studied. The results showed that the average volume diameter of the microcapsules was 101.2 µm. The microcapsules were in the shape of full spheres, with a smooth surface, low viscosity, and high elasticity. Microencapsulation improved the thermal stability of Osmanthus essential oil and promoted the slow release of essential oil. The synthesized microcapsules showed good storage stability under refrigerated and dark conditions, which indicated that microcapsules had broad application prospects in food, medicine, and other fields. Practical Application: In this study, we prepared a polyurea membrane to encapsulate Osmanthus essential oil microcapsules by interfacial polymerization. The encapsulation conditions of the microcapsules were optimized and the structure of the microcapsules was characterized in this study. The results showed that microcapsules had a full spherical shape with a smooth surface, high elasticity, good sustained‐release ability, good thermal stability, and storage stability. These properties indicated that microcapsules have good application prospects and can be used as a high‐quality flavor with a long residual effect and high thermal stability for food and cosmetic scope. [ABSTRACT FROM AUTHOR]