Film-forming Solutions Research Articles

Newfangled Topical Film-Forming Solution for Facilitated Antifungal Therapy: Design, Development, Characterization, and In Vitro Evaluation.

Luliconazole is a broad-spectrum topical antifungal agent that acts by altering the synthesis of fungi cell membranes. Literature suggests that the recurrence of fungal infection can be avoided by altering the pH of the site of infection. Studies have also suggested that fungi thrive by altering skin pH to be slightly acidic, i.e., pH 3-5. The current study is aimed to design, develop, characterize, and evaluate an alkaline pH-based antifungal spray solution for antifungal effects. Luliconazole was used as an antifungal agent and an alkaline spray was formulated for topical application by using Eudragit RS 100, propylene glycol (PG), water, sodium bicarbonate, and ethanol via solubilization method. Herein, sodium bicarbonate was used as an alkalizing agent. Based on DSC, FTIR, PXRD, scanning electron microscopy (SEM), and rheological analysis outcomes, the drug (luliconazole) and polymer were found to be compatible. F-14 formulation containing 22% Eudragit RS 100 (ERS), 1.5% PG, and 0.25% sodium bicarbonate was optimized by adopting the quality by design approach by using design of experiment software. The viscosity, pH, drying time, volume of solution post spraying, and spray angle were, 14.99 ± 0.21 cp, 8 pH, 60 s, 0.25 mL ± 0.05 mL, and 80 ± 2, respectively. In vitro drug diffusion studies and in vitro antifungal trials against Candida albicans revealed 98.0 ± 0.2% drug diffusion with a zone of inhibition of 9 ± 0.12 mm. The findings of the optimized luliconazole topical film-forming solution were satisfactory, it was compatible with human skin, and depicted sustained drug release that suggests promising applicability in facilitated topical antifungal treatments.

Nano Edible Coatings and Films Combined with Zinc Oxide and Pomegranate Peel Active Phenol Compounds Has Been to Extend the Shelf Life of Minimally Processed Pomegranates

Edible coating and film from chitosan and incorporating it with the action of ZnONPs on active phenol compounds from extracts of pomegranate peel (PPE) The physical and chemical properties of edible films composed of zinc oxide ZnONPs and active phenol compounds extracted from pomegranate peel (PPE) were investigated. Adding ZnONPs with active phenol compounds from extracted pomegranate peel(PPE) to chitosan films can provide safe edible films, decrease microbial growth and consequently prolong the shelf life of pomegranates, as well as improve the physiochemical stability of the pomegranate. The substances used in this experiment were film with a (A) extract of pomegranate peels (PPE), 5% (0.1%), (B)ZnONPs 1% (0.02%), (C) ZnONPs 2% (0.04%), (D) ZnONPs 3% (0.06%), (E) ZnONPs 1%/PPE1% (0.02%), (F) ZnONPs 2%/PPE2% (0.04%), (G) ZnONPs 3%/PPE3% (0.06%) wt% of chitosan on quality attributes and prolonging the shelf life of pomegranates were stored in plastic containers at 2 °C and 90-95% relative humidity for 20 days. The treatments of (G) ZnONPs 3%/PPE3% (0.06%) loaded on chitosan as well as chitosan and (D) ZnONPs 3% (0.06%) reduced the weight loss, had excellent microbial count until 20 days of storage, and recorded the lowest microbial count and mould & yeast colonies. Other chemical properties, such as total soluble solids content, acidity, anthocyanin content, firmness, and ascorbic acid, were investigated. Results indicated that ZnONPs 3%/PPE3% (0.06%) loaded on chitosan or ZnONPs 3% (0.06%) are the best treatments for preserving pomegranate arils. It was found that the best measurements were that the film-forming nan emulsion solutions decreased by E% 110 nm and B% 134 nm. Nano followed treatment, F% 188.7 nm, compared to nano edible films, which were A 0% 1312 nm.

Organic Acids Modified Starch–CMC Based Biodegradable Film: Antibacterial Activity, Morphological, Structural, Thermal, and Crystalline Properties

A novel organic acid-modified starch and carboxymethyl cellulose (CMC) based films plasticized with glycerol were prepared from unconventional tikhur starch (Curcuma angustifolia) by solution casting. Wet milling was used in the laboratory to extract starch from the tikhur rhizome. Carboxymethyl cellulose, at a concentration of (0.2 g−1 starch dry basis) was blended with the starch to improve its film-forming properties. Three different treatments with varying organic acids (lactic, citric, and acetic acid) with a concentration of 5% w/w of starch (2 ppm) in a film-forming solution were given. The effect of organic acid incorporation on the antibacterial, morphological, structural, thermal, and crystalline properties of developed films was studied. The minimum inhibitory concentration values of the three organic acids against gram-negative (E. coli) and gram-positive (S. aureus) bacteria were measured using the tube dilution method. The MIC results revealed that lactic acid and citric acid are effective against both gram-negative and gram-positive bacteria, while acetic acid showed more effectiveness against gram-negative bacteria (E. coli). MBC results revealed that organic acids have potent bactericidal activity. Citric acid resulted in higher inhibition for gram-positive bacteria (S. aureus) compared to gram-negative bacteria (E. coli.). While acetic acid showed higher inhibition for E. coli. than S. aureus. Lactic acid displayed similar inhibition against both S. aureus and E. coli. Among different organic acids, lactic acid incorporation resulted in a more homogeneous, transparent, and thermally stable film. As evidenced by the micrographs, the lactic acid incorporation resulted in a compact film structure without any visible cracks. While X-ray diffraction showed an increase in crystalline properties due to organic acid modification. In this study, it was indicated that modification with organic acids (polycarboxylic acids) effectively improved the overall properties of developed films depending on the type of organic acid used. The developed films have the potential to replace harmful synthetic films in food packaging.

Effect of film forming solution pH on antibacterial, antioxidant and structural characteristics of edible films from modified quinoa protein

The active packaging films were developed from the ultrasound or heat modified quinoa protein (QP) infused with lysozyme, by varying the pH of film forming solution (FFS). It was observed that, due to the increase in the solubility of ultrasonicated or heat-treated QP at higher pH, there was a decrease in the moisture content, light transmittance, solubility, and water vapor permeability of the prepared films. On the other hand, increasing the pH of FFS, an increase in the thickness, tensile strength, elongation at break, color, total phenolic content (TPC), and antioxidant activity (AA) was observed. Morphological analysis revealed that there developed the rough and irregular surfaces in the films when the pH of FFS was lowered. In the antibacterial activity, the film prepared at pH 7.5 had shown the highest inhibitory zones of 27.70 mm, 25.48 mm, and 24.90 mm for Staphylococcus spp , Streptococcus agalactiae and Enterococcus faecalis , respectively, It was noteworthy that the pH of FFS was detrimental in TPC and hence the AA. The FTIR analysis indicated that the higher pH of FFS had induced favorable structural changes, stable intermolecular interactional compatibility, and higher ordered molecular structure in the QP films, The X-ray diffraction analysis showed a decrease in the film intensity and an increase in the crystallinity, whereas the thermal analysis indicated an increase in T g up to 43.88 °C at higher pH. Hence the films developed at higher pH, while portraying an enhanced physicochemical and structural characteristic had also shown the lowered antibacterial and antioxidant characteristics. • An active packaging films has been developed using variable pH of film forming solution (FFS). • Lysozyme infused film at pH 7.5 showed highest solubility and bioactivity. • Higher pH of FFS induced structural integrity as depicted by FTIR analysis. • Film prepared at lower FSS pH were less smooth with irregular surface than higher pH. • Higher pH values were detrimental in antimicrobial and antioxidant potential of films.

Effect of catechin and tannins on the structural and functional properties of sodium alginate/gelatin/ poly(vinylalcohol) blend films

The catechin and tannins as crosslinking and antioxidant compounds were added into sodium alginate/gelatin/poly(vinyl alcohol) (SA/GEL/PVA) blend film with 0.5%, 2%, and 5% (based on the total mass of polymers), respectively. This study aims to investigate the effect of different polyphenols on the structural and functional properties of food packaging film. Molecular interactions among polyphenols and polymers in film-forming solution (FFS) were analyzed based on the rheological behavior, low field nuclear magnetic resonance (LF-NMR), and the changes in structural characteristic of modified films were analyzed through Fourier transform infrared spectra (FTIR), Scanning electron mcroscopy (SEM) and X-ray diffraction (XRD) analysis. The results indicated that the crosslinking degree of the polymer network in FFSs modified by tannins was higher than that of catechin. The mechanical properties, water insolubility, water vapor barrier performance and antioxidant activity of the blend film were improved by polyphenols addition. The film modified by 2% tannins showed the highest tensile strength and elongation at break in comparing with catechin modified films. This study demonstrated that the tannins have a great potentiality in enhancing the structure and function of SA/GEL/PVA blend film. • The viscosity of FFSs modified by tannin was higher than catechin. • Tannin produce denser network structure in FFSs to decrease the water mobility. • The film modified by 2% tannin processed the highest mechanical properties. • Both tannin and catechin produced some aggregation structure in modified film.

Innovative design of bio-functional Persian gum-based edible films by incorporating crocin and cinnamaldehyde: Free versus single and double emulsion fabrication techniques

The objective of this research was to fabricate a new generation of bio-functional Persian gum-based films via the co-delivery of crocin and cinnamaldehyde. Different loading strategies using single W/O and O/W emulsions and W 1 /O/W 2 double emulsions were used to find how the distribution of bioactives in the film suspension can modify their physicochemical and biological properties compared to those prepared with the free forms of bioactives. The incorporation of emulsion structures significantly decreased the surface tension of film-forming solutions, but their viscosity remained relatively constant. The good compatibility between Persian gum and cinnamaldehyde/crocin was confirmed by FTIR and XRD. The optical, mechanical, and microstructural attributes of the films were more affected by the incorporation of the free form of bioactives. The UV–Vis light barrier property and hydrophobicity of the film were improved after incorporating single and double emulsions. However, the greater stability of bioactives within double emulsion against different pH (2 and 7) and temperatures (25 and 75 °C) produced more superior antibacterial and antioxidant activities. Furthermore, the homogenous distribution of double emulsion in the film matrix led to more resistant and extensible films. • Persian gum-based film was fortified with co-delivery of crocin and cinnamaldehyde. • Comparison was made between free and single and double emulsions loading techniques. • Mechanical and optical properties were more affected by free forms of bioactives. • Double emulsion strategy led to superior antibacterial and antioxidant activities. • Emulsion-based films were transparent but with high UV/Vis barrier properties.

Inhibitory effect of reuterin-producing Limosilactobacillus reuteri and edible alginate-konjac gum film against foodborne pathogens and spoilage microorganisms

The possible inhibitory effects against foodborne pathogens and spoilage microorganisms of two strains (DSM 20016 and DSM 17938) of reuterin-producing Limosilactobacillus reuteri, and an edible alginate-konjac gum film containing L. reuteri cells and in situ produced reuterin was evaluated. An in vitro antimicrobial screening study indicated that both L. reuteri strains and the edible film showed inhibitory effects against B. cereus, C. perfringens and P. aeruginosa, and towards the fungi F. oxysporum, C. gloeosporioides, A. alternata, and P. digitatum. In addition, L. reuteri DSM 20016 was able to produce reuterin in situ (46.67 mmol/L) in alginate-konjac gum film-forming solution through anaerobic glycerol bioconversion. Furthermore, after the edible film production by extrusion technique, both L. reuteri and reuterin were successfully trapped (98 and 67.6 %, respectively). Further studies must be conducted to detect the exact metabolites related to the inhibition effects against foodborne pathogens and spoilage microorganisms.

Effects of pre-emulsion prepared using sucrose esters with different hydrophile-lipophile balances on characteristics of soy protein isolate emulsion films

The preparation of emulsion films using pre-emulsification has received extensive attention due to the enhancement of oil binding capacity. However, the different effects of water in oil (W/O) and oil in water (O/W) pre-emulsions on the physicochemical properties of films are still unclear. Therefore, the soy protein isolate (SPI) based emulsion films were prepared by W/O or O/W pre-emulsion using sucrose esters with different hydrophile-lipophile balances to investigate the properties of SPI emulsion (SPIE) films. The viscosity, storage moduli, and loss moduli of film-forming solutions (FFSs) with O/W pre-emulsion were higher than those of FFSs with W/O pre-emulsion. The oil droplets of FFSs with W/O pre-emulsion were large and uneven, and the oil droplet size increased after drying. Phase separation and macroporous network appeared in cross-sectional of SPIE films with W/O pre-emulsion according to scanning electron microscope images. Meanwhile, the SPIE films with W/O pre-emulsion demonstrated higher oil concentration and hydrophobicity on the upper surface compared with the SPIE films with O/W pre-emulsion. Low tensile strength, glass transition temperature, and high elongation at break and transparency value of SPIE films with O/W pre-emulsions were founded. The water vapor permeability of SPIE films with W/O pre-emulsion increased with the addition of oil, whereas the opposite trend appeared in that with O/W pre-emulsion. In conclusion, the structure and porosity of emulsion films could be affected by the pre-emulsion types, which can determine the application ranges.

Development and application on strawberries of edible coatings based on yam and corn starch added with Rio Grande cherry

This work aimed to evaluate the properties of biofilms based on corn and yam starch incorporated with Rio Grande cherry (Eugenia involucrata DC) and its encapsulates and use them as a coating on strawberries. The extraction of phenolic compounds from the Rio Grande cherry was optimized, and total flavonoids, antioxidant, and antimicrobial activity were analyzed for the best point. Five compositions of the film-forming solution based on yam and corn starch were evaluated and analyzed for thickness, opacity, moisture content, solubility, antioxidant activity and antimicrobial activity. In addition, antifungal analyses, water loss and color change were performed on the strawberries with and without coating. The cherry extract had a total phenolic content of 526.85 mg EAG 100 g−1 and high antioxidant activity (16.99 μM Trolox g−1 in ABTS; 31.71 mM ferrous sulfate g−1 in FRAP; 94.96% in b-carotene assay), as well as inhibition of Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae microorganisms. Adding 2% of starch and 20% of plasticizer in relation to the starch had the best overall results. Films with 0.5% fruit content had greater antioxidant activity than those with 0.03% encapsulate. Film thickness increased when encapsulated agents or fruit were incorporated, but opacity decreased. The solubility of the films changed from 0.34% for corn starch to 0.30% for encapsulate and 0.37% for fruit; yam starch films were completely soluble. Strawberries with yam starch film had the lowest water loss. Films without plasticizers showed colony formation on the seventh day of analysis. Thus, it is suggested that incorporating Rio Grande cherry fruit and its encapsulates in edible toppings could be feasible.

Mechanical properties of tef starch based edible films: Development and process optimization

The non-biodegradable synthetic plastic is one of the greatest challenges facing the food packaging business since it seriously harms the environment. To solve this problem, non-biodegradable plastic may be disposed of more affordably and with less harm on the environment by using edible starch-based biodegradable film. Therefore, the present study was focused on the development and optimization of tef starch based edible films based on mechanical properties. In this study response surface methodology was employed by considering 3–5g of tef starch, 0.3–0.5% of agar and 0.3–0.5% of glycerol. The prepared film showed the tensile strength of 17.97–24.25 Mpa, elongation break of 1.21–2.03%, elastic modulus of 17.58–108.69 MPa, puncture force of 2.55–15.02 N, puncture formation of 9.59–14.95 mm. The findings showed that as glycerol concentrations in the film-forming solution increased, the prepared tef starch edible films' tensile strength, elastic modulus, and puncture force declined while their elongation at break and puncture deformation increased. Tef starch edible films' mechanical characteristics, including as tensile strength, elastic modulus, and puncture force, were increased by the increase of agar concentration. The optimized (from 5 gm tef starch, 0.4 g agar and 0.3% glycerol) tef starch edible film exhibited higher tensile strength, elastic modulus, and puncture force while lower elongation at break and puncture deformation. The composite edible film based tef starch with agar exhibited good mechanical properties and can be suggested for application in food industry as food packaging.

Novel active edible food packaging films based entirely on citrus peel wastes

This is the first report on mobilizing three value-added compounds from citrus peel wastes to fabricate novel/cost-effective active edible films with multiple functionalities. Pectin extracted from grapefruit peels (GFP) with improved recovery yields (48.35%), displayed better thermal stability and superior physico-chemical properties to commercial citrus pectin ( CPec ) with regard to methoxylation degree, anhydrouronic acid and moisture contents. Active films plasticized with PEG 400 (25% w/w of polymer) were prepared by solution casting upon incorporating 0.04% (w/v) of grapefruit peel methanolic extract (GFPE) and maltodextrin-encapsulated lemon peel extract (MD-LPE) into grapefruit pectin ( GFPec ; 3% w/v) matrix. The bioactive ingredients and the optimally active ( GFPec -GFPE/MD-LPE) film-forming solutions exhibited strong radical scavenging and antimicrobial activities against foodborne pathogens. SEM micrographs of the optimal active film revealed good dispersion and compatibility of ingredients in agreement with the FTIR data that confirmed no modifications in the film's functional groups. GFPE and MD-LPE capsules synergistically enhanced the tensile strength, thermal, water vapor/UV barrier properties and soil biodegradability of the elaborated transparent flexible films compared to CPec -based films. Wrapping of artificially contaminated cherry tomatoes with optimal active films inhibited the growth of a four-strain cocktail suspension of E. coli O157:H7 by ∼1.6 log units after 6 days of chilled storage. Overall, the study highlights the benefits of citrus wastes valorization, provides evidence of potential applicability of the fabricated novel edible GFPec -based films as candidates for antimicrobial food packaging, shelf life extension of fresh-cut produce, and supports their consideration as promising eco-friendly alternatives to synthetic food packaging materials. • Three value-added compounds were mobilized from citrus peels for film fabrication. • High methoxyl grapefruit pectin showed superiority to commercial citrus pectin. • Free and encapsulated extracts had remarkable antioxidant and cytotoxic activities. • Incorporating both ingredients enhanced thermal and barrier properties of films. • The novel active film inhibited E. coli O157:H7 growth on wrapped cherry tomatoes.

Marine Collagen-Based Antibacterial Film Reinforced with Graphene and Iron Oxide Nanoparticles.

It has become more widely available to use biopolymer-based films as alternatives to conventional plastic-based films due to their non-toxic properties, flexibility, and affordability. However, they are limited in application due to deficiencies in their properties. The marine collagen was the specimen for the present study. Thus, the main objective was to reinforce marine collagen-based films with 1.0% (w/w of the dry polymer weight) of iron oxide nanoparticles (IO-NPs), graphene oxide nanoparticles (GO-NPs), or a combination of both oxides (GO-NPs/IO-NPs) as antibacterial and antioxidant additives to overcome some of the limitations of the film. In this way, the nanoparticles were incorporated into the film-forming solution (2% w/v in acetic acid, 0.05 M) and processed by casting. Thereafter, the films were dried and analyzed for their physicochemical, mechanical, microstructural, and functional properties. The results show that the effective combination of GO-NPs/IO-NPs enhanced the physicochemical properties by increasing the water contact angle (WCA) of the films from 77.2 to 84.4° and their transparency (T) from 0.5 to 5.2. Furthermore, these nanoparticles added antioxidant and antibacterial value to the films, with free radical inhibition of up to 95.8% and 23.8 mm of bacteria growth inhibition (diameter). As a result, both types of nanoparticles are proposed as suitable additives to be incorporated into films and enhance their different properties.

Preparation and Evaluation of Vitamin D3 Supplementation as Transdermal Film-Forming Solution.

Vitamin D3 is available in oral and injectable dosage forms. Interest in the transdermal route as an alternative to the oral and parenteral routes has grown recently. In this study, several film-forming solutions for the transdermal delivery of vitamin D3 were prepared. They contained 6000 IU/mL of vitamin D3 that formed a dry and acceptable film in less than 5 min after application. The formulations consisted of ethanol and acetone 80:20, and one or more of the following ingredients: Eudragit L100-55, PVP, PG, limonene, oleic acid, camphor, and menthol. Vitamin D3 release was studied from both the film-forming solution and pre-dried films using a Franz diffusion cell. The film-forming solution released a significant amount of vitamin D3 compared to the dry film, which is attributed mostly to the saturation driving force due to the evaporation of volatile solvents. In vitro permeation studies through artificial skin Strat M® membrane revealed that the cumulative amount of vitamin D3 permeated after 24 h under the experimental conditions was around 800 IU across 3.14 cm2. The cumulative permeation curve showed faster permeation in earlier stages. Young's modulus, viscosity, and pH of the formulations were determined. Most of the formulations were stable for 3 weeks.

Sustained-release antibacterial gelatin films: Effects of diatomite/carvacrol complex on their structure, physicochemical and antibacterial properties

Antibacterial diatomite/carvacrol (D/C) complex was prepared by utilizing diatomite as an effective carrier of carvacrol, and further incorporated into gelatin with different amounts (0–30%, w/w based on gelatin) to develop a series of antibacterial gelatin-based films. D/C complex was found to have appropriate interaction and compatibility with gelatin matrix as revealed by FTIR and SEM analysis. With increasing D/C complex content, light transmission, moisture content, water solubility and tensile strength of the films decreased, whereas elongation at break and water vapor permeability increased. More importantly, an apparent antibacterial effect began to be observed for the film-forming solution containing 10% (or more) D/C complex, and the subsequent film exhibited a much slower release rate of carvacrol towards food simulant (60 wt% glycerol solution) than gelatin film with the same content of carvacrol. Therefore, the developed antibacterial gelatin films with desirable physical and sustained-release properties have great potential for active food packaging applications.

Rheological performance of film-forming solutions and barrier properties of films fabricated from cold plasma-treated high methoxyl apple pectin and crosslinked by Ca2+: Impact of plasma treatment voltage

Sustainable and “green” technologies, such as cold plasma are gaining attention in recent times for improving the functional properties of hydrocolloids. Chemical modifications of hydrocolloids require several chemicals and solvents, which are not environment-friendly. The major objective of the study was to understand the impact of plasma treatment (170–230 V|15 min) on the rheology of film-forming solutions (FFS) and the barrier properties of pectin films. The film-forming properties of plasma-treated pectin were investigated in the presence of two plasticizers, namely, glycerol and polyethylene glycol (PEG) 400. The effects of cross-linking by CaCl2 on the rheology of FFS and barrier properties of the films were discussed. A voltage-dependent decrease in the apparent viscosity of FFS was observed. The viscoelastic properties of the FFS were enhanced due to cross-linking. Glycerol exhibited a better plasticizing effect than PEG. Cross-linking and increasing voltage synergistically contributed towards lower oxygen and carbon dioxide transmission rates. The moisture sorption rate and capacity of the films increased with the voltage of the treatment. The resistance to extension of the films made from glycerol and PEG decreased with voltage, with no significant change in extensibility. On the other hand, the cross-linking by Ca2+ and plasma treatment enhanced the resistance to extension for the films made from both the plasticizers. While the increasing hydrophilicity and opacity of the films were a major drawback of plasma modification, the increase in UV barrier property of the films was an advantage of the modification.

Functional Chitosan-Calcium Carbonate Coatings for Enhancing Water and Fungal Resistance of Paper Materials.

The objective of this study was to increase the water resistance of paper while providing fungal resistance using a bio-based coating made from chitosan. The water resistance was improved through the surface control of roughness using modified calcium carbonate particles. The higher the quantity of particles in the film-forming solution, the higher the surface hydrophobicity of the paper. The addition of particles was found to counterbalance the chitosan hydrophilicity through the control of the coatings' penetration in the paper bulk. As a consequence, the wetting time and liquid water resistance were enhanced. The antifungal activity of the film-forming solutions and coated paper was also investigated against the growth of Chaetomium globosum, which was selected as a model strain able to contaminate paper materials. The results reveal that the antifungal activity of chitosan was improved by a possible synergic effect with the bicarbonate ions from the mineral particles.

Characterization of gallic acid-Chinese yam starch biodegradable film incorporated with chitosan for potential use in pork preservation

The widely use of petroleum-based plastics causes serious environmental pollution and oil resource shortage. In this work, biodegradable films were prepared based on gallic acid (GA)-induced Chinese yam starch (YS) and chitosan (CS). The fresh-keeping effect of biodegradable films on the pork meat preservation were investigated. The prepared GA/YS/CS biodegradable films exhibited thinner thickness and better light transmittance, because CS effectively decreased the viscosity of film-forming solution and weaken its internal link structure. The SEM results and mechanical results revealed that the YS, GA, and CS had a good compatibility, GA modification and adding CS markedly improved the tensile strength of YS-based film, because the interaction between CS and starch molecular was facilitate owing to the NH3+ of CS tended to form hydrogen bonds with the hydroxyl group of starch. Sensory analysis results suggested that GA/YS/CS films can effectively improve the quality of pork during storage compared to the package of polyethylene film. In summary, the prepared GA/YS/CS film in this work had practical application potential in pork preservation due to its excellent mechanical, antibacterial, oxidation resistance properties, and the development and application of biodegradable starch film can greatly reduce the increasingly serious environmental pollution pressure.

Efficiency Analysis of Fuel Cell Components with Ionic Poly-Arylether Composite Membrane.

We use polyethylene glycol as an additive to explore how the hydrogen bonding of this additive changes the properties of SA8 blended sulfonated polyetheretherketone (SPEEK) composite films. We mixed a 5%wt polyethylene glycol solution into a 12.5%wt SA8 solution, and then prepared a film with a total weight of 40 g at a ratio of 1:99. The SA8 (PEG) solution was prepared and then mixed with 5%wt SPEEK solution, and a film-forming solution with a total weight of 8g in different mixing ratios was created. Polyethylene glycol (PEG) was mixed into the sulfonated polyarylether polymer SA8 to form physical cross-linking. Therefore, the sulfonated polyether ether ketone SPEEK was mixed in, and it exhibited good thermal stability and dimensional stability. However, there was some decrease in proton conductivity as the proportion of SPEEK increased. Although SPEEK mixed with sulfonated polymer reduces the proton conductivity, the physical cross-linking of PEG can improve the proton conductivity of the composite membrane, and adding SPEEK can not only solve the problem of the high sulfonation film swelling phenomenon, it can also improve the dimensional stability of the film through the hydrogen bonding force of PEG and obtain a composite film with excellent properties.

МОДЕЛИРОВАНИЯ СВОЙСТВ МАТЕРИАЛОВ СЕНСОРОВ ГАЗОВ НА ОСНОВЕ КОБАЛЬТСОДЕРЖАЩЕГО ПОЛИАКРИЛОНИТРИЛА С ИСПОЛЬЗОВАНИЕМ РЕГРЕССИОННОГО АНАЛИЗА И НЕЙРОННЫХ СЕТЕЙ

A modeling approach has been developed for materials based on organic semiconductorsand their physicochemical and gas-sensitive properties. For modeling, such methods as multiplelinear and non-linear regression, neural networks were used. As an input vector for modeling theproperties of metal-containing polyacrylonitrile are the parameters of the technological process offorming materials: the mass fraction of the alloying component (cobalt) in the film-forming solution,technological modes of IR annealing: temperature, time of the first and second stages. Outputvector - functional characteristics and physical and chemical properties of materials (resistivity,gas sensitivity coefficient, stability and selectivity). Abstract—Metal–carbon systems with Co metalparticles based on polyacrylonitrile have been synthesized by IR pyrolysis. The resistance valueswere measured in the medium of the detected gas (chlorine). Modeling of the functional characteristicsand physicochemical properties of materials was carried out on the basis of data obtainedfrom the study of 200 samples of cobalt/polyacrylonitrile films. Multiple linear regression proved to be effective for predicting resistivity values. Neural networks are used to predict the gassensitivity coefficient, selectivity, and stability of cobalt-containing polyacrylonitrile films.An artificial neural network in the form of a multilayer perceptron was built to predict the gassensitivity coefficient of gas sensor elements based on the data of technological processes for obtainingmaterial (mass fraction of the alloying component (cobalt) in the film-forming solution,technological modes of IR annealing: temperature, time of the first and second stages). Complianceof the synthesized model was checked: with experimental data: correlation coefficientR=0.82, root-mean-square error st=0.017. The synthesized models satisfactorily describe the collecteddata within the experimental error, which makes it possible to optimize the chemical compositionand heat treatment conditions.

Intelligent colorimetric soy protein isolate-based films incorporated with curcumin through an organic solvent-free pH-driven method: Properties, molecular interactions, and application

The preparation of intelligent colorimetric films based on soy protein isolate and curcumin at different final pHs was investigated by using blending and pH-driven methods with curcumin-free films as blank controls. It was found that the films loaded with curcumin using the pH-driven method exhibited enhanced ductility and water resistance with an elongation at break of 122 ± 6% and water vapor permeability of 1.70 ± 0.01 × 10 −10 g·m/m 2 ·Pa·s. The Fourier transform infrared (FTIR) spectroscopy results showed that curcumin was loaded in the film network mainly through hydrogen bonds and hydrophobic interactions. The curcumin encapsulated using the pH-driven method was present in an amorphous form, which effectively suppressed the adverse effect of curcumin blending on film opacity and increased the UV blocking ability of the films. The high encapsulation efficiency and reduced thermal degradation of curcumin resulted in enhanced antioxidant activity of the films with high 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of 102.91 ± 0.83 Trolox equivalent (TE)/g and 211.47 ± 5.20 μg TE/g, respectively. Furthermore, films showed better color responsiveness to volatile amines than curcumin-blended films. In particular, the films generated with a film-forming solution at pH 8 had the strongest color sensitivity in the presence of low concentrations of volatile amines. In shrimp storage experiments, only the films prepared using the pH-driven method identified the freshness of the shrimp based on visual observation. Hence, the pH-driven method might represent a promising organic solvent-free method for the preparation of intelligent packaging films. • An organic solvent-free strategy was proposed to prepare curcumin-loaded films. • Amorphous curcumin was loaded by hydrogen bonds and hydrophobic interactions. • The films had good antioxidant activity and color response to volatile amines. • The films were suitable for real-time freshness monitoring of shrimp.