scholarly journals Carboxymethyl Bacterial Cellulose from Nata de Coco: Effects of NaOH

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 348
Author(s):  
Pornchai Rachtanapun ◽  
Pensak Jantrawut ◽  
Warinporn Klunklin ◽  
Kittisak Jantanasakulwong ◽  
Yuthana Phimolsiripol ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Bacterial Cellulose ◽  
Chemical Structure ◽  
Room Temperature ◽  
Water Vapor Permeability ◽  
Acetobacter Xylinum ◽  
Vapor Permeability ◽  
Cellulose Powder ◽  
Percent Elongation ◽  
Elongation At Break

Bacterial cellulose from nata de coco was prepared from the fermentation of coconut juice with Acetobacter xylinum for 10 days at room temperature under sterile conditions. Carboxymethyl cellulose (CMC) was transformed from the bacterial cellulose from the nata de coco by carboxymethylation using different concentrations of sodium hydroxide (NaOH) and monochloroacetic acid (MCA) in an isopropyl (IPA) medium. The effects of various NaOH concentrations on the degree of substitution (DS), chemical structure, viscosity, color, crystallinity, morphology and the thermal properties of carboxymethyl bacterial cellulose powder from nata de coco (CMCn) were evaluated. In the carboxymethylation process, the optimal condition resulted from NaOH amount of 30 g/100 mL, as this provided the highest DS value (0.92). The crystallinity of CMCn declined after synthesis but seemed to be the same in each condition. The mechanical properties (tensile strength and percentage of elongation at break), water vapor permeability (WVP) and morphology of CMCn films obtained from CMCn synthesis using different NaOH concentrations were investigated. The tensile strength of CMCn film synthesized with a NaOH concentration of 30 g/100 mL increased, however it declined when the amount of NaOH concentration was too high. This result correlated with the DS value. The highest percent elongation at break was obtained from CMCn films synthesized with 50 g/100 mL NaOH, whereas the elongation at break decreased when NaOH concentration increased to 60 g/100 mL.

scholarly journals Effect of Monochloroacetic Acid on Properties of Carboxymethyl Bacterial Cellulose Powder and Film from Nata de Coco

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 488
Author(s):  
Pornchai Rachtanapun ◽  
Warinporn Klunklin ◽  
Pensak Jantrawut ◽  
Noppol Leksawasdi ◽  
Kittisak Jantanasakulwong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bacterial Cellulose ◽  
Chemical Structure ◽  
Water Vapor Permeability ◽  
Raw Material ◽  
Food Preparation ◽  
Monochloroacetic Acid ◽  
Vapor Permeability ◽  
Cellulose Powder ◽  
Elongation At Break

Nata de coco has been used as a raw material for food preparation. In this study, the production of carboxymethyl cellulose (CMC) film from nata de coco and the effect of monochloroacetic acid on carboxymethyl bacterial cellulose (CMCn) and its film were investigated. Bacterial cellulose from nata de coco was modified into CMC form via carboxymethylation using various concentrations of monochloroacetic acid (MCA) at 6, 12, 18, and 24 g per 15 g of cellulose. The results showed that different concentrations of MCA affected the degree of substitution (DS), chemical structure, viscosity, color, crystallinity, and morphology of CMCn. The optimum treatment for carboxymethylation was found using 24 g of MCA per 15 g of cellulose, which provided the highest DS at 0.83. The morphology of CMCn was related to DS value; a higher DS value showed denser and smoother surface than nata de coco cellulose. The various MCA concentrations increased the mechanical properties (tensile strength and percentage of elongation at break) and water vapor permeability of CMCn, which were related to the DS value.

scholarly journals Preparation, properties and applications of wheat gluten edible films

2000 ◽  
Vol 9 (1) ◽  
pp. 23-35 ◽  
Author(s):  
P. TANADA-PALMU ◽  
H. HELÉN ◽  
L. HYVÖNEN
Keyword(s):  
Weight Loss ◽  
Tensile Strength ◽  
Water Vapor ◽  
Wheat Gluten ◽  
Single Layer ◽  
Water Vapor Permeability ◽  
Edible Films ◽  
Bilayer Film ◽  
Vapor Permeability ◽  
Elongation At Break

Edible films from wheat gluten were prepared with various amounts of glycerol as a plasticizer. Water vapor permeability, oxygen permeability, tensile strength and percentage elongation at break at different water activities ( aw ) were measured. Films with low amounts of glycerol had lower water vapor and oxygen permeabilities, higher tensile strength and lower elongation at break. Wheat gluten coatings reduced weight loss during two weeks of storage for cherry tomatoes and sharon fruits compared to uncoated controls. A bilayer film of wheat gluten and beeswax significantly lowered weight loss from coated cheese cubes compared to single layer coating of wheat gluten.;

The Structure and Properties Research on Poly(Lactide-Co-Trimethylene Carbonate) Film Prepared by Blow Molding

2013 ◽  
Vol 750-752 ◽  
pp. 1930-1933
Author(s):  
Jiang Ping Chang ◽  
Hong Li Li ◽  
Ying Jie Zhang ◽  
Guo Xian Zhou ◽  
Ming Long Yuan
Keyword(s):  
Tensile Strength ◽  
Ring Opening ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Trimethylene Carbonate ◽  
Blown Films ◽  
Elongation At Break ◽  
Blow Molding ◽  
Food And Beverage ◽  
Carbonate Film

The poly (lactide-co-trimethylene carbonate) copolymers are prepared by ring opening polymerization and catalyzed by SnOct and their films are prepared by blow molding. The 1HNMR study demonstrates that PLA-PTMC copolymers were successfully obtained and the graft way is A-B model. The water vapor permeability (WVP) of the films decreases with the increasing TMC content due to the formation of denser structure. The mechanical measurement reveals that the tensile strength of blown films has been declined with the increasing TMC content, but the elongation at break is improved and the tensile strength can be satisfied for the requirement of film product. Therefore, the copolymer film will be great prospect in the application of food and beverage packing.

Preparation and Characterization of Cellulose/Modified Nano-SiO2 Composites Packaging Films by NMMO Technology

2011 ◽  
Vol 233-235 ◽  
pp. 1162-1166 ◽  
Author(s):  
Feng Jun Wang ◽  
Jian Qing Wang ◽  
Mei Xu
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Tensile Strength ◽  
Water Vapor ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Elongation At Break ◽  
Packaging Films ◽  
Pure Cellulose ◽  
Cellulose Composites

Cellulose-based composites packaging films containing various amounts of modified nano-SiO2 were prepared by utilizing hardwood pulps as natural cellulose resource through NMMO-technology to improve the mechanical properties, permeability for oxygen and water vapor etc. The tensile strength, elongation at break, thermal stability and permeability of the cellulose composites films as a function of the content of modified nano-SiO2 were studied. The investigation suggested that the capabilities of composites films with 2 wt.% modified nano-SiO2 added were improved largely, compared to pure cellulose films, when the diameter of particles is 30nm. The tensile strength was increased from 8.95 to 17.37 MPa and the elongation at break of the cellulose composites films was improved from 41.11% to 58.34%. The composites films with rational mechanical properties have adjustable oxygen permeability (7.90×10-15-72.18×10-15 cm3·cm/cm2·s·Pa) and water vapor permeability (7.12×10-13-5.32×10-13g·cm/cm2·s·Pa). And thermal stability of the composites films was advanced through adding modified nano-SiO2.

scholarly journals DEVELOPMENT OF A BIODEGRADABLE COMPOSITE FILM FROM CHITOSAN, AGAR AND GLYCEROL BASED ON OPTIMIZATION PROCESS BY RESPONSE SURFACE METHODOLOGY

2021 ◽  
Vol 55 (7-8) ◽  
pp. 849-865
Author(s):  
PARTHIBAN FATHIRAJA ◽  
SUGUMAR GOPALRAJAN ◽  
MASILAN KARUNANITHI ◽  
MURALIDHARAN NAGARAJAN ◽  
MOHAN CHITRADURGA OBAIAH ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Response Surface Methodology ◽  
Water Vapor ◽  
Composite Film ◽  
Response Surface ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Hydroxyl Groups ◽  
Elongation At Break ◽  
Puncture Resistance

The aim of the study has been to develop a biodegradable film from marine polysaccharides. The optimization of polysaccharides quantity for the composite film was sought by empirical response surface methodology. The Box–Behnken Model Design was applied to optimize the concentration of chitosan (1.0-2.0% (w/v), agar (1.0-2.0% (w/v) and glycerol (0.1-0.5% (w/v) as independent variables to achieve the goal. The overall desirability function fits with the quadratic model (0.862043) at a significant level (p < 0.05) for the optimum concentration of chitosan (1.5% (w/v), agar (2.0% (w/v) and glycerol (0.41% (w/v) to obtain the minimum water vapor permeability (7.25 10-10g m m-2 Pa-1 s-1) and maximum tensile strength (12.21 Ma P), elongation at break (7.32%) and puncture resistance (16.18 N) in the optimized composite film. The absolute residual errors of experimental and predicted responses were between 1.24 and 3.56% acceptable levels. Attenuated total reflection–Fourier transform infrared spectroscopy confirmed the intermolecular non-covalent hydrogen bond between the hydroxyl groups of agar and glycerol with the amino group of chitosan. 3D atomic force microscopy images revealed that the chitosan, agar and glycerol film has layer-by-layer smooth surface properties due to homogenous interaction among the polysaccharides; this provides the film with good mechanical properties and with functional application. Chitosan was found to be responsible for the lower level of water vapor permeability and higher puncture resistance of the film. Tensile strength and elongation at break were influenced by agar and glycerol. The whiteness of the film was negatively affected with the concentration of chitosan.

Effect of Plasticizer on the Physical and Mechanical Characteristics of Caesalpinia pulcherrima Gum Edible Film

2020 ◽  
Vol 987 ◽  
pp. 112-117
Author(s):  
Wancheng Sittikijyothin ◽  
Khanaphit Khumduang ◽  
Chularat Hongvaleerat ◽  
Rattanaphol Mongkholrattanasit
Keyword(s):  
Tensile Strength ◽  
Propylene Glycol ◽  
Water Vapour ◽  
Water Vapor Permeability ◽  
Edible Films ◽  
Water Vapour Permeability ◽  
Edible Film ◽  
Vapor Permeability ◽  
Vapour Permeability ◽  
Elongation At Break

The gum edible films were prepared from Caesalpinia pulcherrima seeds. The effects of plasticizer types and contents on physical and mechanical properties of gum edible film were investigated. Three plasticizers as glycerol and sorbitol and propylene glycol at different adding concentrations (0.5%, 1.0%, and 1.5%) were used. Glycerol provided flexible and sticky films with the highest water vapour permeability and elongation at break but the lowest tensile strength. In contrast, propylene glycol provided brittle films with the highest tensile strength but the lowest elongation at break and water vapour permeability. In addition, increasing in plasticizer content resulted in decreased tensile strength concomitant with an increased in elongation at break and water vapor permeability.

scholarly journals Effect of Tea Polyphenols on Curdlan/Chitosan Blending Film Properties and Its Application to Chilled Meat Preservation

Coatings ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 262 ◽  
Author(s):  
Ying Zhou ◽  
Tonglin Xu ◽  
Yu Zhang ◽  
Chong Zhang ◽  
Zhaoxin Lu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Composite Films ◽  
Radical Scavenging ◽  
Water Vapor Permeability ◽  
Tea Polyphenols ◽  
Moisture Loss ◽  
Vapor Permeability ◽  
Film Properties ◽  
Antioxidant Efficiency ◽  
Elongation At Break

Incorporating phenolic acids into polysaccharide films improves their physical properties, in turn improving their potential commercial applicability as a preservation material for different foods. This study aimed to develop films from curdlan and tea polyphenols, and determine the effect of their contents on the water vapor permeability (WVP) and mechanical properties (tensile strength and elongation at break) of the films. Different ratios of tea polyphenols were incorporated into the curdlan-based films to improve their properties. The results obtained showed that the tensile strength and elongation at break of films were likely to be significantly decreased by adding tea polyphenols, especially at a content of 0.6%, which resulted in a 50% decrease. Meanwhile, the WVP and moisture content of the films was also decreased. However, a low WVP can prevent moisture loss from food. Other film properties, such as antioxidant efficiency, were also investigated. The results showed that the antioxidant potential of the film can be improved by tea polyphenols. The composite films were also applied to the preservation of chilled meat, which resulted in the shelf life being extended by about 3–5 days. Some properties, such as water resistance and DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging capacity of the composite film, were improved.

scholarly journals COMPARATIVE STUDIES OF THE EDIBLE FILM BASED ON LOW PECTIN METHOXYL WITH GLYCEROL AND SORBITOL PLASTICIZERS

2017 ◽  
Vol 6 (2) ◽  
pp. 158-167 ◽  
Author(s):  
Yuli Darni ◽  
Herti Utami ◽  
Rina Septiana ◽  
Rizka Aidila Fitriana
Keyword(s):  
Tensile Strength ◽  
Water Vapor ◽  
Water Vapor Permeability ◽  
Edible Films ◽  
Edible Film ◽  
Vapor Permeability ◽  
Percent Elongation ◽  
Weight Variation ◽  
Agitation Time ◽  
Plasticizer Concentration

This study aims to compare the characteristics of mechanical and water vapor permeability of edible film based on low pectin methoxyl from cocoa skin with glycerol and sorbitol as plasticizer. In the research also added CaCO3 filler with the weight variation of 0; 0.2; and 0.4 gr. Pectin from cocoa peel was isolated by extraction use ammonium oxalic at a temperature of 85oC, pH of 3.6 for 60 minutes. An edible film synthesized at a temperature of 85oC to the agitation time of 50 minutes. 200 mesh of pectin used with the variation of glycerol and sorbitol plasticizer concentration are 1, 2 and 3% in volume. Edible films produced were dried at a temperature of 55oC for 6 hours. The results of the study obtained in 0.2 gr CaCO3 concentration and 1% glycerol of edible films has a tensile strength of 0.3267 mpa, percent elongation of 12.84%, modulus young of 2.5441 mpa, and the water vapor permeability of 4.1676 g/m2.day. While in 0.4 gr CaCO3 concentration and 1% sorbitol of edible films has a tensile strength of 6.511 mpa, percent elongation of 2.419%, modulus young of 269.119 mpa, and the water vapor permeability of 5.583 g/m2.day. Based on percent elongation characteristics, glycerol plasticizer made higher elasticity than sorbitol plasticizer. While the addition of filler able to increase tensile strength two times larger than without filler.

scholarly journals Enzymatic and Chemical Cross-Linking of Bacterial Cellulose/Fish Collagen Composites—A Comparative Study

2021 ◽  
Vol 22 (7) ◽  
pp. 3346
Author(s):  
Agata Sommer ◽  
Paulina Dederko-Kantowicz ◽  
Hanna Staroszczyk ◽  
Sławomir Sommer ◽  
Marek Michalec
Keyword(s):  
Thermal Stability ◽  
Bacterial Cellulose ◽  
Secondary Alcohol ◽  
Water Vapor Permeability ◽  
Polymer Chains ◽  
Cross Linking ◽  
Vapor Permeability ◽  
Covalent Bonds ◽  
Fish Collagen ◽  
Chemical Cross Linking

This article compares the properties of bacterial cellulose/fish collagen composites (BC/Col) after enzymatic and chemical cross-linking. In our methodology, two transglutaminases are used for enzymatic cross-linking—one recommended for the meat and the other proposed for the fish industry—and pre-oxidated BC (oxBC) is used for chemical cross-linking. The structure of the obtained composites is characterized by scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy, and their functional properties by mechanical and water barrier tests. While polymer chains in uncross-linked BC/Col are intertwined by H-bonds, new covalent bonds in enzymatically cross-linked ones are formed—resulting in increased thermal stability and crystallinity of the material. The C2–C3 bonds cleavage in D-glucose units, due to BC oxidation, cause secondary alcohol groups to vanish in favor of the carbonyl groups’ formation, thus reducing the number of H-bonded OHs. Thermal stability and crystallinity of oxBC/Col remain lower than those of BC/Col. The BC/Col formation did not affect tensile strength and water vapor permeability of BC, but enzymatic cross-linking with TGGS improved them significantly.

Effect of Castor Oil Impregnation on the Physical and Mechanical Properties of Bacterial Cellulose

2012 ◽  
Vol 3 (1) ◽  
pp. 13-26
Author(s):  
Myrtha Karina ◽  
Lucia Indrarti ◽  
Rike Yudianti ◽  
Indriyati
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Bacterial Cellulose ◽  
Young’S Modulus ◽  
Castor Oil ◽  
Young's Modulus ◽  
Physical And Mechanical Properties ◽  
Scanning Electron Micrographs ◽  
Elongation At Break ◽  
Acetone Water

The effect of castor oil on the physical and mechanical properties of bacterial cellulose is described. Bacterial cellulose (BC) was impregnated with 0.5–2% (w/v) castor oil (CO) in acetone–water, providing BCCO films. Scanning electron micrographs revealed that the castor oil penetrated the pores of the bacterial cellulose, resulting in a smoother morphology and enhanced hydrophilicity. Castor oil caused a slight change in crystallinity indices and resulted in reduced tensile strength and Young's modulus but increased elongation at break. A significant reduction in tensile strength and Young's modulus was achieved in BCCO films with 2% castor oil, and there was an improvement in elongation at break and hydrophilicity. Impregnation with castor oil, a biodegradable and safe plasticiser, resulted in less rigid and more ductile composites.

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