Carbon Dioxide Permeability Research Articles

Biodegradable chitosan-based films decorated with biosynthetic copper oxide nanoparticle for post-harvest tomato preservation.

Biodegradable chitosan-based films decorated with biosynthetic copper oxide nanoparticle for post-harvest tomato preservation.

A Study of the Influence of Packaging Material on the Development of a Pattern in Semi-hard Cheeses Produced Using Propionic Acid Bacteria

Propionic acid bacteria play an important role in the formation of a pattern on cheese produced using them. In recent years, cheese producers have actively used the rindless technology for its ripening, which has made it difficult to obtain a pre-defined cheese pattern. The influence of the type of packaging material, the ripening temperature in the main chamber, and the salting technology on the process of pattern formation in semi-hard cheese with the involvement of propionic acid bacteria has been studied. The pattern in cheese was analyzed using the non-destructive method of magnetic resonance imaging. Our studies have shown that, the pattern formation during the production of semi-hard cheeses using propionic acid bacteria weighing 5–7 kg and a mass moisture fraction of 44–45% depends on the gas permeability of the polymer material used for cheese ripening and on the temperature in the main ripening chamber. The lowest amount of gas was formed when using a polymer material with a carbon dioxide permeability of 50 cm3/(m2 day). The best result was observed when cheese was ripened in packages with CO2 permeability above 1750 cm3/(m2 day) at a temperature of 24°C in the main ripening chamber. The lowering of the temperature in the main chamber to 18°C reduces the volume of formed gas by 5 times. It has also been established that the decrease in the permeability of the polymer material for carbon dioxide from 1750 to 750 cm3/(m2 day) has little effect on the development of a pattern in cheese. Increasing the salt concentration gradient in the surface layer of cheese reduces the volume of eyes formed in the subrind layer, thereby reducing the potential for defects in the finished product.

Increasing the Permeability of Carbon Dioxide and Nitrogen Gases Through a Polymer Membrane Consisting of a Modified Polyether Block Amide and Experimental Design

Increasing the Permeability of Carbon Dioxide and Nitrogen Gases Through a Polymer Membrane Consisting of a Modified Polyether Block Amide and Experimental Design

Investigation of physical, thermal, mechanical and gas permeability properties of low‐density polyethylene/ poly(4‐methyl‐1‐pentene) blend films and their utilization for fresh‐cut fruit and vegetable packaging applications

AbstractIn this study, low density polyethylene/poly(4‐methyl‐1‐pentene) (LDPE/PMP) blend films were prepared by melt compounding in a twin‐screw extruder then film casting in a single screw extruder equipped with a cast‐film. Morphological, thermal, and mechanical properties of flexible blend films were characterized by XRD, SEM, DSC analysis, and tensile tests. Solid‐state viscoelastic properties of samples were also quantified by measuring creep behaviors in DMA. Oxygen and carbon dioxide permeability values of films were measured. Their packaging film application performances were evaluated by observing the textural properties of fresh‐cut bananas stored into LDPE and a blend film bag and monitoring the ethylene, oxygen, carbon dioxide concentrations into the bags for 14 days. It was found that LDPE/PMP blends showed partially miscible structure but yielded highly transparent films. DSC results pointed out that the PMP significantly reduced the degree of crystallinity value of LDPE. On the other hand, PMP improved tensile strength and elastic modulus of LDPE. Creep tests indicated that the PMP addition significantly reduced the creep resistance and relaxation time of LDPE. This study clearly signified that the PMP dramatically increased the oxygen permeability value of LDPE. It has also been concluded that LDPE/PMP blend films can be used as a highly permeable packaging material for successfully extending the shelf life of fresh‐cut fruits and vegetables.Highlights LDPE/PMP films, despite being partially miscible, are highly transparent and made through melt compounding and film casting. Adding PMP to LDPE reduces crystallinity but improves tensile strength and elasticity, as shown by DSC tests. PMP reduces LDPE's creep resistance and quickens relaxation time, according to DMA creep tests. PMP greatly increases LDPE's oxygen permeability, ideal for gas‐transmitting packaging. LDPE/PMP film packaging prolongs the shelf life of fresh produce, proven in a banana storage study.

Effect of graphene oxide/layered double hydroxide modified by 7‐octenyltrimethoxysilane on the mechanical and gas barrier properties of fluoroelastomers

AbstractLayered double hydroxide/graphene oxide (GLDH) composites (SGLDH) modified by 7‐octenyltrimethoxysilane (7‐OTOS) were prepared by co‐precipitation method. The structure and morphology of SGLDH were characterized using x‐ray diffraction, Fourier‐transform infrared spectroscopy (FTIR), x‐ray photoelectron spectroscopy, scanning electron microscopy (SEM), high‐resolution transmission electron microscopy, energy‐dispersive x‐ray spectroscopy, and thermogravimetric analysis. According to the obtained results, 7‐OTOS was successfully grafted onto graphene oxide (GO) and layered double hydroxide (LDH) surfaces. 7‐OTOS was grafted on both GO and LDH surfaces, which is why the amount of LDH loaded on the SGLDH surface was significantly increased compared with that on the GLDH composite. The filler‐matrix interfacial interactions of the SGLDH‐filled fluoroelastomer composites were characterized using contact angle analysis, dynamic mechanical analysis, RPA analysis, FTIR, SEM, and cross‐linking density tests. It was indicated that the interfacial interactions between the SGLDH and matrix were significantly improved, and the SGLDH was well dispersed in the fluoroelastomer composites. In addition, the gas barrier properties and mechanical properties of the fluoroelastomer composites were tested. The carbon dioxide permeability coefficients of the fluoroelastomer composites filled with 10‐phr SGLDH increased by about 32.1% and 20.3%, and the tensile strengths increased by about 47.6% and 27.7%, respectively, compared with those of the fluoroelastomer composites filled with 10‐phr LDH and GLDH.Highlights SLDH nanocomposites are based on silyl ether linkages to increase LDH loading. Elastomer nanocomposites exhibited interfacial cross‐linking mechanism. Interfacial interactions were exhibited between FKM and SGLDH. FKM/SGLDH exhibited enhanced gas barrier properties (+32%) compared to FKM. FKM/SGLDH exhibited enhanced mechanical properties (+47%) compared to FKM.

Apple pectin-based active films to preserve oil: Effects of naturally branched phytoglycogen-curcumin host

Apple pectin-based active films to preserve oil: Effects of naturally branched phytoglycogen-curcumin host

Effect of vinyl acetate/dibutyl maleate copolymers on gas transport properties of poly(ethylene oxide-b-amide 6) membranes: a comprehensive study on permeability, diffusivity, solubility, and permselectivity of carbon dioxide

Effect of vinyl acetate/dibutyl maleate copolymers on gas transport properties of poly(ethylene oxide-b-amide 6) membranes: a comprehensive study on permeability, diffusivity, solubility, and permselectivity of carbon dioxide

The interpretation of diverging hydrogen and carbon dioxide permeations with temperature across silica-based membranes

The interpretation of diverging hydrogen and carbon dioxide permeations with temperature across silica-based membranes

Immobilization of carbonic anhydrase on modified PES membranes for artificial lungs.

The introduction of carbonic anhydrase (CA) onto an extracorporeal membrane oxygenation (ECMO) membrane can improve the permeability of carbon dioxide (CO2). However, existing CA-grafting methods have limitations, and the hemocompatibility of current substrate membranes of commercial ECMO is not satisfactory. In this study, a 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC)/N-hydroxy succinimide (NHS) activation method is adopted to graft CA with CO2-catalyzed conversion activity onto a polyethersulfone (PES) membrane, which is prepared by a phase inversion technique after in situ crosslinking polymerization of 1-vinyl-2-pyrrolidone (VP) and acrylic acid (AA) in PES solution. The characterization results reveal that CA has been grafted onto the modified PES membrane successfully and exhibits catalytic activity. The kinetic parameters of esterase activity verify that the grafted amount of active CA increases with an increase in the concentration of the CA incubation solution. The CA-grafted membrane (CA-M) can accelerate the conversion of bicarbonate to CO2 in water and blood, which demonstrates the special catalytic activity towards bicarbonate of CA. Finally, blood compatibility tests prove that the CA-M does not lead to hemolysis, shows suppressed protein adsorption and increased coagulation time, and is suitable for application in ECMO. This work demonstrates a green and efficient method for preparing bioactive materials and has practical guiding significance for subsequent pulmonary membrane research and ECMO applications.

Polyelectrolyte Complexation of Chitosan and WS2 Nanotubes

AbstractThe inclusion of tungsten disulphide nanotubes (WS2 NTs) in chitosan, plasticized with glycerol, facilitates the formation of a polyelectrolyte complex. The glycerol interrupts the intramolecular hydrogen bonding between chitosan chains allowing positively charged protonated amines of chitosan to form a complex with negatively charged oxygen ions chemisorbed to the tungsten atoms in defects. These interactions, with the unique mechanical and chemical properties of WS2 NTs, result in a chitosan film with superior properties relative to unfilled chitosan. Even at low WS2 NT loadings (≤1 wt%), the Young's modulus (E) increases by 59%, tensile strength (σ) by 40% and tensile toughness by 74%, compared to neat chitosan, without sacrificing ductility. Addition of highly dispersed WS2 NTs significantly improves the gas barrier properties of chitosan, with a 50% reduction in oxygen permeability, while the addition of both glycerol and WS2 NTs to chitosan effectively reduces the carbon dioxide permeability by 80% and the water vapor transmission rate by 90%. The intrinsic antimicrobial efficacy of chitosan against both Gram‐positive and Gram‐negative bacteria is enhanced on inclusion of WS2 NTs. Polyelectrolyte complexation of WS2 NTs and glycerol‐plasticized chitosan provides a cost‐effective, sustainable route to biodegradable films with desirable mechanical, gas barrier properties, and antimicrobial efficacy suitable for food packaging applications.

Properties of konjac glucomannan/curdlan-based emulsion films incorporating camellia oil and the preservation effect as coatings on ‘Kyoho’ grapes

The strategy of emulsion coating was used for grape preservation. Camellia oil (CO) was incorporated with KGM/curdlan (KC) to fabricate KC-CO emulsion systems. KC-CO emulsions were analyzed by droplet size distribution and confocal laser scanning microscopy (CLSM), and KC-CO films were investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), mechanical properties, dissolution, gas permeability, water contact angle (WCA). KC-CO coating was used for preservation of ‘Kyoho’ grapes. The results indicated that the addition of CO had a positive effect on KC system. CO could form a uniform emulsion with KC, and the droplets were evenly dispersed in the KC matrix. KC-CO films displayed a continuous microstructure, and elongation at break (EAB) was improved, while tensile strength decreased. The dissolution, water vapor permeability (WVP), and WCA were significantly enhanced, while the permeability of oxygen and carbon dioxide exhibited no advantage compared with KC film. KC-CO-10 possessed optimal properties and was selected as an emulsion coating for preservation. The results suggested that KC-CO-10 significantly maintained the appearance, total solid and acid content of ‘Kyoho’ grapes, and delayed the weight loss and firmness decrease. This study contributed to the understanding of polysaccharide-lipid emulsion system and the applications.

Polymer Additives with Gas Barrier and Anti-Aging Properties Made from Asphaltenes via Supercritical Ethanol.

Asphaltene is often regarded as an undesirable by-product of petroleum processing, possesses vast reserves with little market value. The typical routes of consuming asphaltene, namely burning and landfilling, pose significant environmental challenges. In this study, low-value asphaltene is converted into high-value ethylated carbon clusters (ECC) using a supercritical ethanol technique. The resulting ECC powder demonstrates promising properties for high density polyethylene (HDPE) composite applications. The effects of incorporating ECC on the mechanical, gas barrier, and anti-aging properties of the composite are investigated. Results show that a 1wt.% ECC led to a 4.2% and 43.5% increase in tensile strength and elongation at break, a reduction of 45.8% and 30.7% in oxygen and carbon dioxide permeability. Furthermore, ECC exhibits effective UV spectrum absorption and conversion in the wavelength range of 400-600nm, providing protection against UV spectrum damage to HDPE. The incorporation of ECC not only enhances the properties of polymer composites but also sequesters carbon within the polymer matrix, enabling the valorization of asphaltene while mitigating environmental impact.

Effect of Graphene Oxide-Modified CaAl-Layered Double Hydroxides on the Carbon Dioxide Permeation Properties of Fluoroelastomers.

This work aimed to investigate the CO2 gas barrier and mechanical properties of fluorine rubber nanocomposites filled with Ca/Al layered hydroxide (graphene oxide [GO]/LDH-Ca2Al) modified by GO. GO/LDH-Ca2Al nanocomposite fillers were prepared by depositing Ca/Al layered hydroxide (LDH-Ca2Al) into the surface of alkalized GO (Al-GO). The prepared GO/LDH-Ca2Al nanocomposite fillers and complexes were characterized by Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) for structural and micromorphological characterization. The results showed that GO/LDH-Ca2Al was successfully prepared with strong interactions between Al-GO and LDH, and the compatibility of GO/LDH-Ca2Al nanocomposite fillers with the polymer was significantly improved compared with that of LDH-Ca2Al. Consequently, both the fracture strength (σb) and strain (εb) of GO/LDH-Ca2Al nanocomplexes remarkably increased, and they exhibited excellent mechanical properties. Differential scanning calorimetry and thermogravimetric analysis were used to characterize the thermal stability of GO/LDH-Ca2Al nanocomposite fillers, and GO/LDH-Ca2Al nanocomposite fillers have better thermal stability than LDH-Ca2Al. The reaction products (S-LDH-Ca2Al and S-GO-Ca2Al) of LDH-Ca2Al and GO/LDH-Ca2Al with CO2 were characterized using XRD and TGA, respectively, and the results show that LDH-Ca2Al reacts readily and chemically with CO2, resulting in a lower diffusion coefficient of CO2 in the LDH-Ca2Al nanocomplexes than that of the GO/LDH-Ca2Al nanocomplexes and leading to the destruction of the laminar structure of LDH-Ca2Al, while GO/LDH-Ca2Al has better CO2 resistance stability. GO/LDH-Ca2Al nanocomplexes exhibited a reduced content of hydroxyl groups with pro-CO2 nature exposed on the surface of LDH-Ca2Al, improving the interfacial interaction between the nanofillers and the rubber matrix and enhancing the dispersion of GO/LDH-Ca2Al in the polymers. Moreover, CO2 in the soluble GO/LDH-Ca2Al nanocomposites was significantly reduced, while the diffusion properties demonstrated weak temperature dependence on solubility. The mechanism of the CO2 gas barrier of polymers filled with GO/LDH-Ca2Al was proposed on the basis of the Arrhenius equation.

High-Barrier, Biodegradable Films with Polyvinyl Alcohol/Polylactic Acid + Wax Double Coatings: Influence of Relative Humidity on Transport Properties and Suitability for Modified Atmosphere Packaging Applications.

Polyvinyl alcohol (PVOH) exhibits outstanding gas-barrier properties, which favor its use as a biodegradable, high-barrier coating on food-packaging films, possibly in combination with modified atmospheres. Nonetheless, its high sensitivity to water can result in a severe loss of barrier properties, significantly limiting its applications with fresh foods and in high-humidity conditions. In this work, the water vapor (PWV) and oxygen permeability (PO2) of high-barrier biodegradable films with PVOH/PLA + wax double coatings were extensively characterized in a wide range of relative humidity (from 30 to 90%), aimed at understanding the extent of the interaction of water with the wax and the polymer matrices and the impact of this on the permeation process. What is more, a mathematical model was applied to the PWV data set in order to assess its potential to predict the permeability of the multilayer films by varying storage/working relative humidity (RH) conditions. The carbon dioxide permeability (PCO2) of the films was further evaluated, and the corresponding permselectivity values were calculated. The study was finally augmented through modified atmosphere packaging (MAP) tests, which were carried out on double-coated films loaded with 0 and 5% wax, and UV-Vis analyses. The results pointed out the efficacy of the PLA + wax coating layer in hampering the permeation of water molecules, thus reducing PVOH swelling, as well as the UV-shielding ability of the multilayer structures. Moreover, the MAP tests underlined the suitability of the double-coated films for being used as a sustainable alternative for the preservation of foods under modified atmospheres.

Scrutinizing different catalytic processes in the (Gd–La) codoped CeO2–NiO-carbonate membrane reactor, implying CO2 permeation mechanisms

Scrutinizing different catalytic processes in the (Gd–La) codoped CeO2–NiO-carbonate membrane reactor, implying CO2 permeation mechanisms

Preparation and characterization of nano-SiO2-modified emulsified film and its application for strawberry preservation

Preparation and characterization of nano-SiO2-modified emulsified film and its application for strawberry preservation

Enhanced water vapor barrier and gas barrier properties of transparent poly(butylene adipate‑co‑terephthalate)/poly(lactic acid)/hexagonal boron nitride nanosheets composite films

Enhanced water vapor barrier and gas barrier properties of transparent poly(butylene adipate‑co‑terephthalate)/poly(lactic acid)/hexagonal boron nitride nanosheets composite films

Transparent chitosan/hexagonal boron nitride nanosheets composite films with enhanced UV shielding and gas barrier properties

Transparent chitosan/hexagonal boron nitride nanosheets composite films with enhanced UV shielding and gas barrier properties

Measuring gas permeability in tight cores at high pressure: Insights into supercritical carbon dioxide seepage characteristics.

Measuring gas permeability in tight cores at high pressure: Insights into supercritical carbon dioxide seepage characteristics.

Performance optimization of polyetherimide‐zeolite 4A mixed matrix membranes for carbon dioxide/methane separation process using response surface methodology

AbstractThe performance optimization studies of zeolite 4A embedded polyetherimide mixed matrix membranes to separate carbon dioxide/methane by simultaneously considering the effect of process parameters on process responses were the focus of this study. Mixed matrix membranes were characterized and analyzed. The thermophysical characteristics of the synthesized membranes were assessed by different analytical equipment. The permeability of pure gases was determined at varying feed pressures (4 bar to 10 bar) to evaluate gas separation performance. Process optimization studies were accomplished by response surface methodology to find the relation of pressure and zeolite loading on carbon dioxide and methane permeability, and carbon dioxide/methane selectivity. The characterization results revealed that all membranes were dense in structure and has improved thermal stability. The spectrometry results confirmed the molecular interaction between polyetherimide and zeolite 4A filler. Gas permeability results showed a more than 90 % increase in carbon dioxide permeability compared to the nascent polyetherimide membrane. Similarly, selectivity of mixed matrix membranes was 45 % higher than polyetherimide membrane. The optimal operating conditions were found to be 20 wt. % zeolite loading and 6 bar pressure with overall desirability of 0.700. These membranes can find potential in various gas separation applications.