Photothermal configuration applied to the study of water vapor permeability in biodegradable films under several water activities

2003 ◽  
Vol 74 (1) ◽  
pp. 761-763 ◽  
Author(s):  
G. Lopez-Bueno ◽  
E. San Martı́n-Martı́nez ◽  
A. Cruz-Orea ◽  
S. A. Tomas ◽  
M. Tufiño ◽  
...  
2012 ◽  
Vol 506 ◽  
pp. 311-314 ◽  
Author(s):  
W. Pimpa ◽  
C. Pimpa ◽  
P. Junsangsree

Fresh durian seed consists largely of starch and can be considered such a suitable raw material for producing biodegradable films. The aim of this work was to develop biodegradable films based on durian seed starch (DSS) and to characterize their water barrier, microscopic and mechanical properties. DSS films were prepared by casting with glycerol as plasticizer. Corn starch and cassava starch, commonly used in food processing, were chosen to prepare films and compare their properties to the DSS-based films. Using a second biopolymer, carboxymethyl cellulose (CMC), in the DSS based composite has been studied as a strategy to improve their important properties. Water vapor permeability and elongation values were improved significantly (p<0.05) when 5% (w/w DSS) CMC was incorporated. Therefore, preparing biodegradable films from DSS is a new alternative for using this raw material which is sometimes much cheaper than commercial starches


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jinshu Liu ◽  
Xiaoyan Ma ◽  
Wenzhao Shi ◽  
Jianwei Xing ◽  
Chaoqun Ma ◽  
...  

Abstract Baicalin, an active flavonoid ingredient of Scutellaria baicalensis Georgi, was extracted by heat reflux extraction and showed the same significance UV absorption property with standard baicalin. Active films were prepared from polyvinyl alcohol (PVA) containing baicalin extract by casting method. The effect of baicalin extracts on the UV-blocking, optical, antioxidant property, water vapor permeability, swelling and mechanical properties of the films were studied. UV–vis transmittance spectra showed that PVA films incorporated with baicalin extract blocked ultraviolet light range from 280–400 nm even with low concentration of baicalin (0.5 wt%) and maintain the high transparency in visible spectrum. The outstanding UV-blocking properties of PVA films incorporated with baicalin extract were also confirmed by Rhodamine B degradation. Baicalin conferred antioxidant properties to PVA films as determined by DPPH radical scavenging activity. Due to the interaction between hydroxy groups of baicalin and PVA molecule, water vapor permeability, swelling and elongation at break of the films were decreased accompanied with the increasing in tensile strength and Young’s modulus. FTIR reveal that the interaction between PVA molecules was significant changed by the introduction of baicalin. These results suggest that PVA film incorporated with baicalin extract can be used for the development of functional protective film.


Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 602
Author(s):  
Carmen Rodica Pop ◽  
Teodora Emilia Coldea ◽  
Liana Claudia Salanţă ◽  
Alina Lăcrămioara Nistor ◽  
Andrei Borşa ◽  
...  

Kefiran is an exopolysaccharide classified as a heteropolysaccharide comprising glucose and galactose in equimolar quantities, and it is classified as a water-soluble glucogalactan. This work aimed to investigate the effect of different extraction conditions of kefiran on the structural and physical properties of the edible films obtained. Fourier-transform infrared spectroscopy and scanning electron microscopy were performed, together with a determinations of moisture content, solubility, water vapor permeability and degree of swelling. The kefiran films presented values of the water vapor permeability between 0.93 and 4.38 × 10−11 g/m.s.Pa. These results can be attributed to the development of a more compact structure, where glycerol had no power to increase the free volume and the water vapor diffusion through their structure. The possible conformational changes in the kefiran film structure, due to the interspersing of the plasticizers and water molecules that they absorb, could be the reason for producing flexible kefiran films in the case of using glycerol as a plasticizer at 7.5% w/w. Moreover, it was observed that the extraction conditions are a significant factor in the properties of these films and their food technology applications.


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.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1782
Author(s):  
Juan Manuel Tirado-Gallegos ◽  
Paul Baruk Zamudio-Flores ◽  
Miguel Espino-Díaz ◽  
René Salgado-Delgado ◽  
Gilber Vela-Gutiérrez ◽  
...  

High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10−11 g/m s Pa) than commercial chitosans films (from 16.06 × 10−11 to 64.30 × 10−11 g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24 to 2.38%). A higher increase in hardness (from 22.32 to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.


Author(s):  
Grégoire David ◽  
Laurent Heux ◽  
Stéphanie Pradeau ◽  
Nathalie Gontard ◽  
Hélène Angellier-Coussy

Abstract This paper aims at investigating the potential of vine shoots (ViSh) upcycling as fillers in novel poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) based biocomposites. ViSh particles of around 50 µm (apparent median diameter) were obtained combining dry grinding processes, and mixed with PHBV using melt extrusion. Thermal stability and elongation at break of biocomposites were reduced with increasing contents of ViSh particles (10, 20 and 30 wt%), while Young’s modulus and water vapor permeability were increased. It was shown that a surface gas-phase esterification allowed to significantly increase the hydrophobicity of ViSh particles (increase of water contact angles from 59° to 114°), leading to a reduction of 27% in the water vapor permeability of the biocomposite filled with 30 wt% of ViSh. The overall mechanical performance was not impacted by gas-phase esterification, demonstrating that the interfacial adhesion between the virgin ViSh particles and the PHBV matrix was already good and that such filler surface treatment was not required in that case. It was concluded that ViSh particles can be interestingly used as low cost fillers in PHBV-based biocomposites to decrease the overall cost of materials.


2009 ◽  
Vol 4 (3) ◽  
pp. 442-449 ◽  
Author(s):  
Yuhua Zhang ◽  
Masatoshi Ishida ◽  
Yutaka Kazoe ◽  
Yohei Sato ◽  
Norihisa Miki

2018 ◽  
Vol 105 ◽  
pp. 637-644 ◽  
Author(s):  
M.K.S. Monteiro ◽  
V.R.L. Oliveira ◽  
F.K.G. Santos ◽  
E.L. Barros Neto ◽  
R.H.L. Leite ◽  
...  

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