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

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.

2000 ◽  
Vol 9 (1) ◽  
pp. 23-35 ◽  
Author(s):  
P. TANADA-PALMU ◽  
H. HELÉN ◽  
L. HYVÖNEN

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.;


Author(s):  
Jie Liu ◽  
Yanchun Liu ◽  
Eleanor M. Brown ◽  
Zhengxin Ma ◽  
Cheng-Kung Liu

The leather industry generates considerable amounts of solid waste and raises many environmental concerns during its disposal. The presence of collagen in these wastes provides a potential protein source for the fabrication of bio-based value-added products. Herein, a novel composite film was fabricated by incorporating vegetable-tanned collagen fiber (VCF), a mechanically ground powder-like leather waste, into a chitosan matrix and crosslinked with genipin. The obtained composite film showed a compact structure and the hydrogen bonding interactions were confirmed by FTIR analysis, indicating a good compatibility between chitosan and VCF. The optical properties, water absorption capacity, thermal stability, water vapor permeability and mechanical properties of the composite films were characterized. The incorporation of VCF into chitosan led to significant decreases in opacity and solubility of the films. At the same time, the mechanical properties, water vapor permeability and thermal stability of the films were improved. The composite film exhibited antibacterial activity against food-borne pathogens. Results from this research indicated the potential of the genipin-crosslinked chitosan/VCF composites for applications in antimicrobial packaging. 


Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 384
Author(s):  
Juan Tirado-Gallegos ◽  
Paul Zamudio-Flores ◽  
José Ornelas-Paz ◽  
Claudio Rios-Velasco ◽  
Guadalupe Olivas Orozco ◽  
...  

Apple starch films were obtained from apples harvested at 60, 70, 80 and 90 days after full bloom (DAFB). Mechanical properties and water vapor permeability (WVP) were evaluated. The apple starch films at 70 DAFB presented higher values in the variables of tensile strength (8.12 MPa), elastic modulus (3.10 MPa) and lower values of water vapor permeability (6.77 × 10−11 g m−1 s−1 Pa−1) than apple starch films from apples harvested at 60, 80 and 90 DAFB. Therefore, these films were chosen to continue the study incorporating ellagic acid (EA). The EA was added at three concentrations [0.02% (FILM-EA0.02%), 0.05% (FILM-EA0.05%) and 0.1% (FILM-EA0.1%) w/w] and compared with the apple starch films without EA (FILM-Control). The films were characterized by their physicochemical, optical, morphological and mechanical properties. Their thermal stability and antioxidant capacity were also evaluated. The FILM-Control and FILM-EA0.02% showed a uniform surface, while FILM-EA0.05% and FILM-EA0.1% showed a rough surface and insoluble EA particles. Compared to FILM-Control, EA modified the values of tensile strength, elasticity modulus and elongation at break. The antioxidant capacity increased as EA concentration did. EA incorporation allowed obtaining films with higher antioxidant capacity, capable of blocking UV light with better mechanical properties than film without EA.


2012 ◽  
Vol 262 ◽  
pp. 557-560
Author(s):  
Shan Shan Gao ◽  
Jian Qing Wang ◽  
Xiu Feng Ma ◽  
Lin Zhao

The barrier properties of the cellulose packaging films are current concerns for the fields of fruits and vegetables fresh-keeping packaging. One such porous films commonly used the pore formers as hole-forming materials whereas the compatibility and dispersity were not better with the cellulose solutions. In this study, the porous cellulose packaging films were prepared with natural broad-leaved pulp and LiCl/DMAc with different types of coagulation baths. The effects of methanol, ethanol, isopropanol, LiCl/DMAc and deionized water coagulation baths on the physical structures, oxygen and water vapor permeabilities and mechanical properties of the films were measured. Based on the scanning electron microscpy (SEM) observation, the cross section was loose when used the alcohol coagulations, especially the films with ethanol coagulation showed dactylopores. It was also found that the oxygen permeability had obviously improving with the effect of ethanol, which compared with water vapor permeability of the films. The porous cellulose packaging films had better mechanical properties and up to 12.7MPa which would satisfy the usage in packaging.


2011 ◽  
Vol 332-334 ◽  
pp. 1739-1742 ◽  
Author(s):  
Ling Li ◽  
Zheng Wei Jin ◽  
Jian Qing Wang

A novel chitosan/poly(vinyl alcohol) composite packaging films were prepared by the casting method, and the effects of chitosan concentration on the structures, mechanical properties, permeability for oxygen and water vapor were discussed in this study. Mechanical properties of these films, which were evaluated by the tensile test and the barrier properties showed that the elongation at break (E) of the composite films decreased rapidly with the addition of chitosan, whereas, the tensile strength (TS) presented an almost opposite trend. Both the water vapour and oxygen transmission rate values were increased with the increasing amount of the chitosan in the composite films. Based on the obtained results, the better property of the composites films would be prepared chitosan/poly(vinyl alcohol) blends at a weight ratio of 3/5, and the tensile strength and elongation at break of the packaging films were 34.12 MPa, 40.24 % respectively. It was also observed that the water vapor permeability coefficient (Pv) and the oxygen permeability coefficient (P) of chitosan/poly(vinyl alcohol) composite packaging films prepared with weight ratio of 3/5 were 1.99×10-15 g•cm/cm2•s•Pa and 7.98×10-16 cm3•cm/cm2•s•Pa respectively. The composite films in this paper can be used in fresh-keeping or other fields as a kind of green packaging material.


2021 ◽  
Vol 55 (7-8) ◽  
pp. 849-865
Author(s):  
PARTHIBAN FATHIRAJA ◽  
SUGUMAR GOPALRAJAN ◽  
MASILAN KARUNANITHI ◽  
MURALIDHARAN NAGARAJAN ◽  
MOHAN CHITRADURGA OBAIAH ◽  
...  

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.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3090
Author(s):  
Anita Ptiček Siročić ◽  
Ana Rešček ◽  
Zvonimir Katančić ◽  
Zlata Hrnjak-Murgić

The studied samples were prepared from polyethylene (PE) polymer which was coated with modified polycaprolactone (PCL) film in order to obtain bilayer films. Thin PCL film was modified with casein/aluminum oxide compound to enhance vapor permeability as well as mechanical and thermal properties of PE/PCL films. Casein/aluminum oxide modifiers were used in order to achieve some functional properties of polymer film that can be used in various applications, e.g., reduction of water vapor permeability (WVTR) and good mechanical and thermal properties. Significant improvement was observed in mechanical properties, especially in tensile strength as well as in water vapor values. Samples prepared with aluminum oxide particles indicated significantly lower values up to 60%, and samples that were prepared with casein and 5% Al2O3 showed the lowest WVTR value.


2021 ◽  
Vol 60 (1) ◽  
Author(s):  
Gema Morales-Olán ◽  
María Antonieta Ríos-Corripio ◽  
Aleida Selene Hernández-Cázares ◽  
Placido Zaca-Morán ◽  
Silvia Luna-Suárez ◽  
...  

Research background. Amaranth flour (Amaranthus hypochondriacus) produces films with excellent barrier properties against water vapor, allowing food preservation, but the mechanical properties are poor versus to synthetic films. One strategy to improve these properties is the incorporation of nanoparticles. The particles can also serve as a vehicle for the addition of antioxidants agents into the films. The objective of this work was to optimize the formulation for preparation of amaranth flour films treated with antioxidant chia (Salvia hispanica L.) extract-loaded chitosan particles using RSM. Experimental approach. Chitosan nanoparticles with the extract were synthesized by ionic gelation, and the films were made by the casting method. Three independent variables were assigned: amaranth flour (4-6 %), glycerol (25-35 %), and chitosan nanoparticles loaded with the chia extract (0-0.75 %). We then evaluated the physical (thickness), mechanical (tensile strength, Young´s modulus, and elongation), barrier (water vapor permeability, moisture, and water solubility), and antioxidant properties of the films. The experimental results of the properties were analyzed using a Box-Behnken experimental design generating 15 runs with three replicates at the central point. Results and conclusions. Second and third order polynomial models were obtained from the ANOVA analysis of the evaluated responses, and high coefficients of determination were found (0.91-1.0). The films presented a water vapor permeability of 0.82-2.39·10-7 (g·mm)/(Pa·s·m2), a tensile strength of 0.33-1.63 MPa, and antioxidant activity of 2.24-5.65 %. The variables had different effects on the films: The glycerol negatively affected their properties, and the permeability values increased with amaranth flour concentration. The nanoparticles improved the mechanical, barrier, and antioxidant properties of the films versus films without nanosystems. The optimal formulation was 4 % amaranth flour, 25 % of glycerol, and 0.36 % of chitosan nanoparticles. The optimized films had better mechanical (1.62 MPa) properties, a low water vapor permeability value (0.91·10-7 (g·mm)/(Pa·s·m2)), and moderate antioxidant activity (6.43 %). Novelty and scientific contribution. The results show the effect of chitosan nanoparticles on the properties of amaranth flour films for the first time. The resulting equations are useful in the design of food packaging.


Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3236
Author(s):  
Peng Yin ◽  
Wen Zhou ◽  
Xin Zhang ◽  
Bin Guo ◽  
Panxin Li

In order to improve the mechanical properties and water resistance of thermoplastic starch (TPS), a novel reinforcement of dialdehyde lignocellulose (DLC) was prepared via the oxidation of lignocellulose (LC) using sodium periodate. Then, the DLC-reinforced TPS composites were prepared by an extrusion and injection process using glycerol as a plasticizer. The DLC and LC were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the effects of DLC content on the properties of the DLC/TPS composites were investigated via the evaluation of SEM images, mechanical properties, thermal stability, and contact angles. XRD showed that the crystallinity of the DLC decreased due to oxidation damage to the LC. SEM showed good dispersion of the DLC in the continuous TPS phase at low amounts of DLC, which related to good mechanical properties. The tensile strength of the DLC/TPS composite reached a maximum at a DLC content of 3 wt.%, while the elongation at break of the DLC/TPS composites increased with increasing DLC content. The DLC/TPS composites had better thermal stability than the neat TPS. As the DLC content increased, the water resistance first increased, then decreased. The highest tensile strength and elongation at break reached 5.26 MPa and 111.25%, respectively, and the highest contact angle was about 90.7°.


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