scholarly journals Preparation and Characterization of Double-Layered Microcapsules Containing Nano-SiO2

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xue Sun ◽  
Jingcheng Su ◽  
Rui Zhang ◽  
Fangyu Fan
Keyword(s):  
Moisture Content ◽  
Droplet Size ◽  
Gum Arabic ◽  
Core Material ◽  
Wall Material ◽  
Scanning Calorimetry ◽  
Nano Sio2 ◽  
The Core ◽  
The Stability

The double-layered microencapsulation technology has been used in many fields. In this study, the double-layered microencapsulated anthocyanin of Passiflora edulis shells (APESs) was prepared via complex coacervation using gelatin and gum Arabic as the first wall materials (single-layered microcapsules (SMs)) and using gum Arabic containing nano-SiO2 as the second wall material (double-layered microcapsules (DMs)/nano-SiO2) to enhance the stability of the core material. Properties of microcapsules were analyzed on the basis of EE, morphology, scanning electron microscopy (SEM), droplet size, moisture content, and differential scanning calorimetry (DSC). The results showed that the EE values of SMs, DMs, and DMs/nano-SiO2 were 96.12%, 97.24%, and 97.85%, respectively. DMs/nano-SiO2 had the lowest moisture content (2.17%). The average droplet size of DMs/nano-SiO2 (34.93 μm) was higher than those of SMs and DMs. DSC indicated that the melting temperature of DMs/nano-SiO2 was 73.61°C and 45.33°C higher than those of SMs and DMs, respectively. SEM demonstrated that DMs/nano-SiO2 had the smoothest surface compared with the other two kinds of microcapsules. The storage stability of APESs and their microcapsules indicated that the stability of the microcapsules was improved by adding DMs/nano-SiO2 into the wall material of microcapsules. These results indicated double-layered microcapsules containing silica nanoparticles contribute to the stability of the core material.

scholarly journals Microencapsulation of Camelina sativa Oil Using Selected Soluble Fractions of Dietary Fiber as the Wall Material

Foods ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 681 ◽  
Author(s):  
Kanclerz ◽  
Drozińska ◽  
Kurek
Keyword(s):  
Dietary Fiber ◽  
High Efficiency ◽  
Gum Arabic ◽  
Camelina Sativa ◽  
Core Material ◽  
Wall Material ◽  
The Core ◽  
Wall Materials ◽  
Low Efficiency

The aim of the study was to prove the usefulness of microencapsulation of Camelina sativa oil regarding its vulnerability to oxidation caused by oxygen, temperature, and other factors. Pectin, inulin, gum arabic, and β-glucan, each of them mixed with maltodextrin, were used as wall materials and their appropriability to reduce oxidation of the core material was examined. Microcapsules were prepared by spray drying, which is the most commonly used and very effective method. The research confirmed results known from literature, that gum arabic and inulin are most proper wall materials, because they ensure small oxidation increase during storage (4.59 and 5.92 eq/kg after seven days respectively) and also provide high efficiency of process (83.93% and 91.74%, respectively). Pectin turned out to be the least appropriate polysaccharide because it is not able to assure sufficient protection for the core material, in this case Camelina sativa oil, due to low efficiency (61.36%) and high oxidation (16.11 eq/kg after seven days). β-glucan occurred to be the coating material with relatively high encapsulation efficiency (79.26%) but high humidity (4.97%) which could negatively influence the storage of microcapsules. The use of polysaccharides in microencapsulation, except performing the role of wall material, has the advantage of increasing the amount of dietary fiber in human diet.

scholarly journals Effect of MF-Coated Epoxy Resin Microcapsules on Properties of Waterborne Wood Coating on Basswood

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 785 ◽  
Author(s):  
Xiaoxing Yan ◽  
Yijuan Chang
Keyword(s):  
Epoxy Resin ◽  
Mass Fraction ◽  
High Performance ◽  
Impact Resistance ◽  
Color Difference ◽  
Core Material ◽  
Wall Material ◽  
The Core ◽  
Mass Fractions ◽  
The Stability

In this paper, melamine–formaldehyde (MF) was used as the wall material, and epoxy resin was used as the core material to prepare microcapsules. The optical properties, mechanical properties and ageing resistance of waterborne topcoat were investigated by adding different mass fractions of microcapsules into the waterborne topcoat. Through scanning electron microscopy and infrared spectroscopy analysis, the prepared microcapsules of core-wall ratio of 0.50 were more uniform. It was found that when the mass fraction of microcapsules is less than 10.0% and the core–wall ratio is 0.50, the original color difference of the coating can be maintained. With the increase in microcapsule mass fraction, the gloss of the topcoat film gradually decreases. The mass fraction of the microcapsule of 4.0% with the core–wall ratio of 0.50 can maintain the original gloss of 30.0 GU. The topcoat film with the MF-coated epoxy resin microcapsules of the core–wall ratio of 0.50 has high impact resistance, adhesion and hardness. The results showed that the gloss loss and color difference of the coating with the MF-coated epoxy microcapsules were the lowest when the mass fraction of microcapsules was 4.0%, indicating that microcapsules can improve the stability of coating. These results lay a technical foundation for the development and application of high-performance wood coatings.

scholarly journals Influence of wall materials on the microencapsulation of pequi oil by spray drying

2020 ◽  
Vol 23 ◽  
Author(s):  
Fabiana Helen dos Santos ◽  
Bianca Marise Pereira e Silveira ◽  
Lourena Lopes de Souza ◽  
Anna Karolina Cruz Duarte ◽  
Milton Cosme Ribeiro ◽  
...  
Keyword(s):  
Moisture Content ◽  
Antioxidant Capacity ◽  
Size Distribution ◽  
Spray Drying ◽  
Water Activity ◽  
Droplet Size ◽  
Encapsulation Efficiency ◽  
Gum Arabic ◽  
Wall Material ◽  
Wall Materials

Abstract The aim of this study was to assess the influence of the wall materials on the microencapsulation of pequi oil. An emulsion containing pequi oil in the oil phase was microencapsulated by spray drying process at 120 °C using gum Arabic, maltodextrin, or a 25:75 (w/w) mixture of gum Arabic and maltodextrin as wall material. The emulsions were characterized for droplet size, Polydispersity Index (PDI), and zeta potential. Pequi oil microparticles were analyzed for moisture content, water activity, wettability, encapsulation efficiency, antioxidant capacity, and color. Ultrastructural examination was performed by Scanning Electron Microscopy (SEM). The Droplet Size Distribution (DSD) of the emulsions exhibited a relatively wide size distribution (2.67 to 8.96 μm) and high PDI (> 0.3). Smooth microparticles with high encapsulation efficiency (79.17% to 84.20%), and good antioxidant capacity (28.20 to 28.71 μmol Trolox equivalents/g dry extract) were obtained. Microparticles prepared using gum Arabic as wall material had higher antioxidant capacity than that prepared with maltodextrin. All microparticles had satisfactory encapsulation efficiency, water activity, moisture content, and wettability. These results indicate that pequi oil microparticles have characteristics that can contribute to good stability during storage and handling of encapsulated oil. Therefore, pequi oil can be successfully encapsulated by spray drying using gum Arabic, maltodextrin, or 25:75 (w/w) mixture of gum Arabic and maltodextrin as wall materials, but the physicochemical properties of microparticles vary with wall material composition.

SHELL MATERIAL'S PERFORMANCE OF THE MICROCAPSULE FOR ELECTROLYTIC CO-DEPOSITION

2010 ◽  
Vol 24 (15n16) ◽  
pp. 3124-3130 ◽  
Author(s):  
HUI CONG LIU ◽  
XIU QING XU ◽  
WEI PING LI ◽  
YAN HONG GUO ◽  
LI-QUN ZHU
Keyword(s):  
Composite Coating ◽  
Methyl Cellulose ◽  
Water Vapor Permeability ◽  
Core Material ◽  
Vapor Permeability ◽  
Shell Material ◽  
The Core ◽  
Surface Performance ◽  
The Stability ◽  
Positive Effect

The shell material of microcapsules has an important effect on the electrolytic co-deposition behavior, the release of core material and the surface performance of composite coating. This paper discussed the tensile property and the stability of three shell materials including polyvinyl alcohol (PVA), gelatin and methyl cellulose (MC). It is found that these three shell materials have good mechanical strength and flexibility which are favorable to electrolytic co-deposition and stability of microcapsules in composite coating and that MC has well permeability and porosity which has a positive effect on the release of the core material in composite coating. Moreover, the study of the thermal properties and water vapor permeability of the three shell materials showed that their permeability improved with increase of temperature and humidity. In addition, the composite copper coating containing microcapsules with PVA, gelatin or MC as shell material was prepared respectively.

Release Profile of a Model Protein Drug Depending on the Stability of Microspheres Based on Polyelectrolyte Complex

2007 ◽  
Vol 342-343 ◽  
pp. 505-508
Author(s):  
Sung Won Kim ◽  
Yun Sik Nam ◽  
Yeon Jin Min ◽  
Jong Ho Kim ◽  
Kwang Meyong Kim ◽  
...  
Keyword(s):  
Polyelectrolyte Complex ◽  
Coating Layer ◽  
Great Influence ◽  
Release Profile ◽  
Core Material ◽  
Glycol Chitosan ◽  
The Core ◽  
Key Factor ◽  
Model Protein ◽  
The Stability

Stability and disintegration of natural polyelectrolyte complex microspheres for protein drugs delivery have been extensively investigated because of their great influence on the drug release patterns. In this study, we tested stability of microspheres with alginate (Alg) core layered by either chitosan (Chi) or glycol chitosan (GChi) by examining release profiles of fluorophorelabeled bovine serum albumin (BSA) and lysozyme (Lys) from the microspheres. While GChi shell was disintegrated quickly, Chi-shell microspheres showed good stability in PBS. Disintegration of the coated layer induced the core material instable. The results indicated that while the charges of the shell material provided additional diffusion barrier against the protein release, the key factor to hold the proteins inside the microspheres was the integrity of the outer coating layer.

scholarly journals Preparation and Physicochemical Characterization of Softgels Cross-Linked with Cactus Mucilage Extracted from Cladodes of Opuntia Ficus-Indica

Molecules ◽  
2019 ◽  
Vol 24 (14) ◽  
pp. 2531 ◽  
Author(s):  
Luis R. Camelo Caballero ◽  
Andrea Wilches-Torres ◽  
Agobardo Cárdenas-Chaparro ◽  
Jovanny A. Gómez Castaño ◽  
María Carolina Otálora
Keyword(s):  
Physicochemical Characterization ◽  
Wall Material ◽  
Scanning Calorimetry ◽  
Nutritional Properties ◽  
Solubility In Water ◽  
Prepared Composite ◽  
Cactus Mucilage ◽  
Composite Samples ◽  
Vibrational Characterization

A new crosslinking formulation using gelatin (G) and cactus mucilage (CM) biopolymers was developed, physicochemically characterized and proposed as an alternative wall material to traditional gelatin capsules (softgels). The effect of G concentration at different G/CM ratios (3:1, 1:1 and 1:3) was analyzed. Transparency, moisture content (MC), solubility in water (SW), morphology (scanning electron microscopy, SEM), vibrational characterization (Fourier transform infrared, FTIR), color parameters (CIELab) and thermal (differential scanning calorimetry/thermogravimetric analysis, DSC/TGA) properties of the prepared composite (CMC) capsules were estimated and compared with control (CC) capsules containing only G and glycerol. In addition, the dietary fiber (DF) content was also evaluated. Our results showed that the transparency of composite samples decreased gradually with the presence of CM, the G/CM ratio of 3:1 being suitable to form the softgels. The addition of CM decreased the MC, the SW and the lightness of the capsules. Furthermore, the presence of polysaccharide had significant effects on the morphology and thermal behavior of CMC in contrast to CC. FTIR spectra confirmed the CMC formation by crosslinking between CM and G biopolymers. The addition of CM to the softgels formulation influenced the DF content. Our findings support the feasibility of developing softgels using a formulation of CM and G as wall material with nutritional properties.

scholarly journals Preparation and Optimization of Waterborne Acrylic Core Microcapsules for Waterborne Wood Coatings and Comparison with Epoxy Resin Core

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2366 ◽  
Author(s):  
Xiaoxing Yan ◽  
Yu Tao ◽  
Xingyu Qian
Keyword(s):  
In Situ Polymerization ◽  
Urea Formaldehyde ◽  
Paint Film ◽  
Bath Temperature ◽  
Water Bath ◽  
Core Material ◽  
Wall Material ◽  
Formaldehyde Resin ◽  
The Core ◽  
Resin Core

Microcapsules were prepared by in situ polymerization with urea formaldehyde resin as the wall material and Dulux waterborne acrylic acid as the core material. The effects of the core–wall ratio, water bath temperature and depositing time on the morphology, particle size, yield and encapsulation ratio of microcapsules were investigated by orthogonal experiment of three factors and two levels. The results showed that the core–wall ratio had the greatest influence on the performance of microcapsules. When the core–wall ratio was 0.58:1, the water bath temperature was 70 °C, and the depositing time was 5 d, the microcapsule performance was the best. With the increase in depositing time, the yield of microcapsule particles increased gradually, and the microcapsules appeared to show an adhesive phenomenon. However, the long-term depositing time did not lead to complete deposition and agglomeration of microcapsules. When 10.0% concentration of the waterborne acrylic microcapsules with 0.58:1 of core–wall ratio was added to the coatings, the mechanical and optical properties of the coatings did not decrease significantly, but the elongation at break increased significantly. Therefore, this study offers a new prospect for using waterborne acrylic microcapsules to improve the toughness of waterborne paint film which can be cured at room temperature on a wood surface.

scholarly journals Microencapsulation of Lemongrass (Cymbopogon citratus) Essential Oil Via Spray Drying: Effects of Feed Emulsion Parameters

Processes ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 40 ◽  
Author(s):  
Nguyen Phu Thuong Nhan ◽  
Vo Tan Thanh ◽  
Mai Huynh Cang ◽  
Tri Duc Lam ◽  
Nguyen Cam Huong ◽  
...  
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Spray Drying ◽  
Gum Arabic ◽  
Core Material ◽  
Wall Material ◽  
Cymbopogon Citratus ◽  
Encapsulation Process ◽  
Wall Materials ◽  
Lemongrass Essential Oil

The purpose of this study was to attempt the encapsulation of lemongrass (Cymbopogon citratus) essential oil utilizing spray drying technique. An array of process parameters including concentration of wall (15–30%), type of wall materials (maltodextrin, maltodextrin and gum Arabic mixture), and concentration of essential oil (0.5–2.0%) were thoroughly investigated. The results show that the use of sole maltodextrin as encapsulant gave microcapsules characteristics comparable to that of powder produced using maltodextrin and gum Arabic mixture. The encapsulation process that was performed with maltodextrin at the concentration of 30% as wall material and lemongrass essential oil at the concentration of 1.5% as core material showed highest drying yield (84.49%), microencapsulation yield (89.31%) and microencapsulation efficiency (84.75%). Encapsulated essential oils retained most of their major constituents in comparison with the bare essential oils without any significant compromise in product quality.

scholarly journals EFFECT OF DIFFERENT GUM TYPES ON STABILITY OF ANTIOXIDANT COMPONENTS AND PHYSICAL PROPERTIES OF SPRAY DRIED POUZOLZIA ZEYLANICA POWDER

2018 ◽  
Vol 55 (5A) ◽  
pp. 10
Author(s):  
Nguyen Duy Tan
Keyword(s):  
Particle Size ◽  
Moisture Content ◽  
Physical Properties ◽  
Water Activity ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Gum Arabic ◽  
Color Difference ◽  
Antioxidant Power ◽  
The Stability

The objective of this study was to investigate effect of blending three types of different gum (arabic, carrageenan and xanthan) in Pouzolzia zeylanica extract together with maltodextrin as well as encapsulated material during spray-drying process on the stability of antioxidant components (anthocyanin, flavonoid, polyphenol, tannin and antioxidant activities through DPPH radical scavenging capacity, ferrous reducing/antioxidant power FRAP and antioxidant ability index AAI); and physical properties (moisture content, water activity, particle size and morphology as well as the color, nonenzymatic browning) of products. The results showed that the sample which was blended with arabic gum and maltodextrin maintained well bioactive compounds and obtained powder had better quality characteristics than others. In this optimal sample, the content of anthocyanin, flavonoid, polyphenol and tannin were determined as 7.56 ± 0.106 mgCE/100 g, 31.15 ± 1.035 mgQE/g, 27.96 ± 0.380 mgGAE/g, 25.79 ± 0.530 mgTAE/g. The antioxidant activity through DPPH, FRAP and AAI were determined as 75.55 ± 0.65%, 102.87 ± 3.85 mM FeSO4/g and 38.17 ± 11.24. The moisture content, water activity, particle size, the color value of (L, a, b), total color difference (DE) and non enzyme browning (NEB) were determined as 6.42 ± 0.085 %, 0.5142 ± 0.0076, 6.26 ± 0.110 µm, 78.43 ± 0.189, 7.55 ± 0.065, 6.96 ± 0.180, 18.85 ± 0.580 and 0.298 ± 0.015, respectively.

Studies of Elastomer Oxidation via Thermal Analysis

1999 ◽  
Vol 72 (1) ◽  
pp. 165-173 ◽  
Author(s):  
D. J. Burlett
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Oxidation Process ◽  
Industrial Applications ◽  
Scanning Calorimetry ◽  
Thermoanalytical Techniques ◽  
The Stability ◽  
Induction Times ◽  
Oxidation Susceptibility

Abstract Elastomers are used in many industrial applications because of their remarkable toughness and elasticity. However, the source of these properties is also a weakness, in that loss of properties via oxidation is an important factor in their selection. Thermoanalytical techniques, such as differential scanning calorimetry (DSC), provide useful tools for the characterization of the stability of elastomers. DSC can not only be used to determine oxidative induction times under isothermal conditions but can also be used to determine apparent overall activation energies of the oxidation process. An evaluation of these techniques is made and the technique is used to compare the oxidation susceptibility of polybutadienes of different microstructure. The results of these DSC scans are interpreted in terms of the chemistry of the oxidation process using FTIR results.

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