Starch Composite Films Research Articles

Preparation and evaluation of hydrophobic biodegradable films made from corn/octenylsuccinated starch incorporated with different concentrations of soybean oil

Corn/octenylsuccinated starch (C/OS) composite films incorporated with soybean oil (SO) at 0, 0.5%, 1.0%, 1.5% and 2.0% (w/w) were prepared to investigate their physicochemical properties. Fourier transform infrared analysis indicated that low concentrations of SO could facilitate molecular interaction and the formation of hydrogen bonds between starch molecules. All the films exhibited similar diffractograms and lower relative crystallinity values. Scanning electron microscopy and atomicforcemicroscopy showed that the irregular and coarse surface structures of the films were obtained more frequently with increasing SO concentration. A higher contact angle of 76.14° and lower water vapor permeability of 2.46 × 10−12 g cm/cm2 s Pa were obtained with increasing SO content, with the exception of the 2.0% SO sample. The highest tensile strength value of 6.54 MPa was obtained by the C/OS-1.0% SO composite film, while the optimumelongation at break of 71.84% was exhibited by the C/OS-1.5% SO composite film.

Characterization of Aloe vera-banana starch composite films reinforced with curcumin-loaded starch nanoparticles

Abstract Interest in developing biodegradable composite films that can incorporate bioactive substances and have and active role in food packaging, has been growing in the last decades. Curcumin, known for its antimicrobial and antioxidant activity has been proposed as an active molecule that can be incorporated into biodegradable films. This work proposes the development and characterization of composite films made from banana starch and Aloe Vera gel incorporated with curcumin-loaded native and acetylated starch nanoparticles. The effect of the curcumin-loaded nanovehicles in the mechanical, barrier, and thermal properties of the composite films was studied. In this sense, the study noted that inclusion of highly hydrophobic curcumin leads to a reduction of the film’s water vapor permeability while enhancing the film’s tensile strength. Finally, this paper reports the release profiles of curcumin from the composite film in different food simulants, observing that it is possible to control curcumin release in different foodstuffs by changing the characteristics of the nanovehicles incorporated.

Improvement of water vapor barrier and mechanical properties of sago starch‐kaolinite nanocomposites

AbstractThe composite films of sago starch were prepared by incorporation of various amount of kaolinite (K) and kaolinite intercalated by dimethyl sulfoxide (DMSO) (KD) via solution blending method in order to reduce the water vapor transmission and enhance mechanical properties of starch based films. The kaolinite intercalation by DMSO and the composite films were characterized by using X‐ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscope techniques. The result showed that well‐dispersed kaolinite layers were delaminated in the starch matrix attesting to intercalate and exfoliate composite films. The effect of kaolinite content on the water vapor transmission and tensile properties of the composite films was investigated. The water vapor transmission of the starch film (neat starch film ca. 0.132 g.cm3/h) decreased with the addition of K and KD to the starch. It was also observed that the maximum tensile strength (5.18 MPa) was attained for the composite film with 4% by weight of clay content. The improvement in the tensile strength and modulus of starch‐based composites was due to the strong interfacial interaction between matrix and kaolinite clay, correlating to the change of morphology of the starch composite films as revealed by scanning electron microscopy.

The Impact of Lignin Structural Diversity on Performance of Cellulose Nanofiber (CNF)-Starch Composite Films.

Lignin fractions having different molecular weights and varied chemical structures isolated from kraft lignins of both softwood and hardwood via a sequential solvent fractionation technique were incorporated into a tunicate cellulose nanofibers (CNF)—starch mixture to prepare 100% bio-based composite films. The aim was to investigate the impact of lignin structural diversity on film performance. It was confirmed that lignin’s distribution in the films was dependent on the polarity of solvents used for fractionation (acetone > methanol > ethanol > ethyl acetate) and influenced the optical properties of the films. The –OH group content and molecular weight of lignin were positively related to film density. In general, the addition of lignin fractions led to decrease in thermal stability and increase in Young’s modulus of the composite films. The modulus of the films was found to decrease as the molecular weight of lignin increased, and a higher amount of carboxyl and phenolic –OH groups in the lignin fraction resulted in films with higher stiffness. The thermal analysis showed higher char content formation for lignin-containing films in a nitrogen atmosphere with increased molecular weight. In an oxygen atmosphere, the phenol content, saturated side chains and short chain structures of lignin had impacts on the maximum decomposition temperature of the films, confirming the relationship between the chemical structure of lignin and thermo-oxidative stability of the corresponding film. This study addresses the importance of lignin diversities on composite film performance, which could be helpful for tailoring lignin’s applications in bio-based materials based on their specific characteristics.

Development and characterization of biodegradable films from whey protein concentrate, psyllium husk and oxidized, crosslinked, dual‐modified lotus rhizome starch composite

The combined effect of variously chemically modified lotus rhizome starch, whey protein concentrate, psyllium husk and glycerol was evaluated on developed biodegradable films. Dual-modified lotus rhizome starch composite films presented minimum solubility and water vapor permeability and maximum tensile strength among native and modified starch composite films. Elongation at break of dual-modified starch composite films (FLCOS1 , FLCOS2 ) was found to be a maximum, whereas a decrease was observed for FLCOS3 . Oxidized lotus rhizome starch composite films were the most transparent among native and modified starch composite films, whereas crosslinked lotus rhizome starch composite films were the least transparent. Scanning electron microscopy indicated a homogeneous compact surface of oxidized starch composite films, whereas troughs were observed in crosslinked and dual-modified starch composite films. Using whey protein concentrate, psyllium husk and glycerol without any phase separation, smoother films and with compact microstructures were produced. Fourier transform infrared analysis revealed additional peaks for modified starch films, confirming greater interaction among starch and film-forming components, whereas amorphous structure was indicated from X-ray diffraction results of modified starch composite films. Owing to various properties of modified starches, these films find application in edible contact packages and can better be used for products where higher structural integrity and lower water vapor transmission are needed. © 2019 Society of Chemical Industry.

Effects on Surface and Physicochemical Properties of Dielectric Barrier Discharge Plasma-Treated Whey Protein Concentrate/Wheat Cross-Linked Starch Composite Film.

Dielectric barrier discharge (DBD) plasma is a new type of polymer surface modification technology. This study is mainly about the changes in film surface structure and physicochemical properties of whey protein concentrate (WPC)/wheat cross-linked starch (WCS) composite films after DBD plasma treatment with different plasma parameters. The results show that the proper plasma treatment parameters (400W to 60 s) can increase the surface roughness, tensile strength, barrier properties, and thermal stability of the edible film and decrease elongation at break and the water contact angle. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction showed that DBD plasma treatment could increase the content of oxygen-containing groups on the WPC/WCS film surfaces instead of damaging the internal crystal structure. The results showed that use of proper DBD plasma treatment technology has a positive effect on the mechanical and barrier properties and thermal stability of WPC/WCS films. PRACTICAL APPLICATION: DBD plasma treatment can improve the mechanical, barrier, and thermal properties of WPC/WCS films without generating any pollution. The DBD plasma can be potentially applied in the enhancement of edible film properties. WPC/WCS films are more environmentally friendly than plastics and can be a replacement for traditional plastics.

Production of active film based on potato starch containing Zedo gum and essential oil of Salvia officinalis and study of physical, mechanical, and antioxidant properties

In this study, biodegradable/antioxidant active film based on potato starch was provided. Composite films of potato starch/Zedo gum/ Salvia officinalis essential oil were provided in different percents of Zedo gum (0.5–1.5%) and S. officinalis essential oil (0–500 µl). The characters of composite film, including physical, mechanical, and antioxidant properties were studied. The results showed that adding different amounts of Zedo gum and essential oil to starch film causes a significant decrease ( p < 0.05) in moisture content, solubility, and film water vapor permeability (WVP). The film containing 1.5% gum and 500 µl of essential oil had minimum moisture content, solubility, and WVP. Results showed that the addition of Zedo gum significantly increased the thickness and opacity of the films and reduced the transparency of the films. Increasing the essential oil is significant on the film opacity and leads to a decrease in the passage of light from the films. By adding different amounts of gum, the antioxidant content of the films was significantly increased compared to the control film (pure starch film). Also, increasing the concentration of essential oil in the film composition caused a significant increase in the antioxidant activity of the films ( p < 0.05). Modified starch films containing 1.5% gum (without essential oil) with 62.64% antioxidant activity and film with 1.5% gum and 500 µl essential oils with 68.35% antioxidant activity had the highest antioxidant activity. The addition of salvia essential oil and Zedo gum significantly decreased the elongation and tensile strength of the potato starch film ( p < 0.05). Finally, the potato starch composite film containing Zedo gum and salvia essential oil showed excellent physical and antioxidant properties and had an excellent ability to be used in the food packaging industry.

Studies on the properties and biodegradability of PVA/Trapa natans starch (N-st) composite films and PVA/N-st-g-poly (EMA) composite films

The morphological modification of Trapa natans starch was done by grafting the methylmethacrylate (EMA) using ferrous ammonium sulphate‑potassium persulphate as a redox initiator. Different reaction parameters such as reaction temperature, time, monomer concentration, pH and solvent were optimized to get maximum graft yield (56%). The graft copolymers thus formed were characterized by Fourier transform infrared, scanning electron microscopy, X-ray diffraction and TGA/DTA/DTG techniques. PVA/starch (N-st) composite films and PVA/N-Starch-grafted-poly (EMA) composite films were prepared separately by using glycerol as a plasticizer. The effect and content of grafted starch on the mechanical properties, water uptake (%), and biodegradability of the composite films were observed. Elongation at break % of PVA/starch-grafted-poly (EMA) (1:1) increased up to 38.9% of pure PVA/N-starch composites (1:1). With further increase in the ratio of grafted starch from (50% to 70%) Elongation at break, % increased to a great extent. There was 223.14% increased in PVA/starch-grafted-poly (EMA) (3:7) as compared to pure PVA/N-starch (3:7) composite films. The Max stress increased up to 100% in PVA/N-starch-grafted-poly (EMA) (3:7) composite film of pure PVA/N-starch composite films (3:7). There were 41.63% decreases in water uptake in PVA/N-starch-grafted-poly (EMA) (3:7) composite films as compared to PVA/N-starch composite films.

Tensile Properties of Irradiated And Non-Irradiated Poly (L-Lactide) Carboxymethyl Starch And Nano-Hydroxyapatite Composite Film

Tensile Properties of Irradiated And Non-Irradiated Poly (L-Lactide) Carboxymethyl Starch And Nano-Hydroxyapatite Composite Film

Tensile, barrier, dynamic mechanical, and biodegradation properties of cassava/sugar palm fiber reinforced cassava starch hybrid composites

The hybrid composite was prepared from cassava bagasse (CB) and sugar palm fiber (SPF) by casting technique using cassava starch (CS) as a matrix and fructose as a plasticizer. The chemical composition and physical properties of SPF and CB were studied in this work. SPF was added at different loadings of 2, 4, 6, and 8% dry starch to the CS/CB composite films with 6% CB. The addition of SPF influenced the hybrid properties. It was observed that the addition of 6% SPF to the composite film increased the tensile strength and modulus up to 20.7 and 1114.6 MPa, respectively. Also, dynamic-mechanical properties of the hybrid composites were investigated using a DMA test. The incorporation of SPF increased the storage modulus (E’) value from 0.457 GPa of CS to 1.490 GPa of CS-CB/SPF8 hybrid composite film. Moreover, the incorporation of SPF slightly decreased the water vapor permeability (WVP) compared to the CS/CB composites film. It can be concluded that the incorporation of SPF led to changes in cassava starch composite film properties, potentially improving the bio-degradability, WVP, and mechanical properties of the film. Based on its excellent properties, CB/SPF-CS hybrid composite films are suitable for various purposes such as packaging, automotive, and agro-industrial applications, at lower cost.

Preparation and properties of microcrystalline cellulose/hydroxypropyl starch composite films

In this paper, microcrystalline cellulose (MCC)/hydroxypropyl starch (HPS) composite films are prepared by the solution casting method, and the effect of different amounts of microcrystalline cellulose on the properties of the films is investigated. The structure of MCC/HPS composite materials is characterized by Fourier transform infra-red and scanning election microscopy, and thermal stability, mechanical properties, hygroscopicity, and water vapor permeability of the composite films are also tested. According to the test results, with increasing MCC amounts, glass transition temperature, thermal stability, and tensile strength of MCC/HPS composite films are improved, while the hygroscopicity and water vapor permeability of MCC/HPS composite materials are decreased. When the content of MCC reaches 6 wt%, the maximum increase of the glass transition temperature is about 9.63 °C, and the tensile strength of MCC/HPS composite films are increased by 300% compared with that of HPS films. Moreover, the addition of MCC helps to expand the application of hydroxypropyl starch in the packaging field.

Preparation of a biodegradable poly(vinyl alcohol)–starch composite film and its application in pesticide controlled release

ABSTRACTWith the herbicide 2,4‐dichlorophenoxyacetic acid (2,4‐D) as a model drug, a series of poly(vinyl alcohol)–starch (PVA–ST) composite films for controlled drug release were prepared by a casting method. The morphology, structure, and release properties were systematically investigated. The results show that when the PVA–ST composite film containing 2,4‐D (PSD) was immersed in water, the drug‐release rate was high, whereas the introduction of sodium montmorillonite (Na‐MMT) and an alginate ion‐crosslinking structure to PSD significantly reduced the release rate and maintained the sustained release of the model drug for a longer period. A leaching experiment through the soil layer showed that the PSD drug‐loaded film with Na‐MMT and the alginate ion‐crosslinking structure (PSDMA) possessed good release properties. The cumulative leached amount of the herbicide 2,4‐D after eight irrigations was reduced to 57.6% from 100%. In addition, the PSDMA film showed favorable mechanical and thermal properties. This composite film is expected to have potential applications in the fields of agriculture, drug delivery, and more. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45051.

Mechanical and Water Barrier Properties of Zein–Corn Starch Composite Films as Affected by Gallic Acid Treatment

Abstract The effect of gallic acid treatment on mechanical and water barrier properties in zein and zein–corn starch composite films was investigated. Four concentrations of corn starch (5 %, 10 %, 15 %, 20 %) were used in composite films making a final solid concentration of 6 % (w/v) in the film forming solution. One composite film containing 10 % corn starch was also prepared in absence of gallic acid for comparison purpose. Gallic acid treatment improved tensile strength (TS) and water vapor permeability (WVP) while solubility was increased in control zein films. On the other hand, gallic acid treatment significantly (p < 0.05) reduced TS and increased WVP in zein–corn starch composite films. Interestingly, mechanical and water barrier properties of composite films prepared in absence of gallic acid were comparatively better than gallic acid treated composite films. These findings provided useful insights in how each individual hydrocolloid in the composite film was differently affected by gallic acid treatment.

Elaboration and characterization of corn starch films incorporating silver nanoparticles obtained using short glucan chains

Nanocomposites are being used as a new type of packaging that has good biodegradability and antibacterial ability and that has wide applicability in the preservation and storage field. Transmission electron microscopy results demonstrated that the AgNPs were spherical in shape with the diameter of 2–6 nm for 48 h reaction time. The mechanical properties of composite films increased after the incorporation of AgNPs. Differential scanning calorimetric and thermogravimetric analysis results showed that the thermal stability of silver–starch composite film was increased through incorporation with AgNPs. The composite films exhibited strong antibacterial activity against Escherichia coli and Staphylococcus aureus, and the composite films were more effective against Gram-negative bacteria (E. coli).

Chitosan molecular weight effect on starch-composite film properties

The aim of this work was to prepare and characterize composite films based on chitosan (CH) and corn starch (CS), analyzing the influence of the chitosan molecular weight (MW) on film structure and functional properties. Three chitosan products were characterized and classified as low (LMW), medium (MMW) and high (HMW) according to its MW. Rheological behavior of filmogenic solutions depend on CH-MW from Newtonian to pseudoplastic one. Chitosan based film physicochemical properties were strongly affected by its molecular weight: the lower the MW the higher the color differences and film solubility. SEM observations demonstrated that plasticized chitosan films exhibited homogeneous structures, the higher the MW the more compact is the structure and the lower is the water vapor permeability (WVP, 4.55 ± 0.6 × 10−11 g/m s Pa.). Likewise, CH and CS were compatible polymers which led to the development of homogeneous blend films. Polymer interactions were evidenced in FTIR spectra by the shifts observed within the region of 1500–1700 cm−1, which reduce the hydrophilic groups’ availability of chitosan matrices, leading to a reduction in WVP of composite films. Mechanical properties of the developed films were performed through different complementary tests. Chitosan MW affects both the type and number of interactions, which determine the matrix structure and characteristics. In HMW-CH matrix polymer–polymer interactions are favored, leading to strong and resistant matrices with high dynamic elastic modulus values. Meanwhile, in LMW-CH one, polymer-plasticizer and polymer–solvent interactions became important and the development of high extensible and soluble materials is privileged.

Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch

In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification.

Effect of Silk Fibroin Reinforcement on the Properties of Potato Starch-Polyvinyl Alcohol Blend Films

Starch and polyvinyl alcohol composite films, reinforced with raw and methylmethacrylate-grafted silk fibroin particles, were prepared by the solution-casting method on leveled plates. Silk fibroin was used as reinforcement for starch and polyvinyl alcohol (St/PVA) blends in order to improve their mechanical and water-resistance properties. The composites were plasticized with citric acid and cross-linked with gluteraldehyde. The reinforced films showed an increase in tensile strength with decrease in elongation at break. The optimized samples were characterized by scanning electron microscopy and were studied for their antibacterial properties. The biodegradable behavior was studied by the soil burial method.

Effects of graphene on the behavior of chitosan and starch nanocomposite films

The objective of this study was to prepare chitosan and starch composite films by the addition of 0–3 wt% graphene nanosheets. The film's tensile strength (TS), tensile modulus (TM), elongation at break (E), moisture uptake (Mu), and water vapor transmission rate (WVTR) were investigated. The surface morphology of the composite films was studied using scanning electron microscopy (SEM). Regardless of biopolymer type, both the TS and TM of the composite films first increased and then decreased with graphene loading. Composite film made with native (unmodified) starch showed lower TS and TM than those with chitosan. Composite films exhibit lower E values than pure chitosan and starch; this is attributed to the increase in the hardness of the films. SEM micrographs indicated that, the surface roughness and phase separation increased with increasing graphene content. This is due to the aggregation of graphene nanosheets, leading to the reduced compatibility of biopolymers. The addition of graphene considerably decreased WVTR and Mu of the composite films. These results indicated that graphene is a promising reinforcing agent for biopolymer composite films. POLYM. ENG. SCI., 54:2258–2263, 2014. © 2013 Society of Plastics Engineers

Incorporation of Rice Starch Affecting on Morphology, Mechanical Properties and Water Vapor Permeability of Glutelin-based Composite Films

Protein is a by-product of rice starch production. The major component of rice protein found in endosperm is glutelin, an alkali-soluble protein. Pure glutelin film could not peel off from the casting plate; however, glutelin films containing starch were easily removed from the plate. Various ratios of rice starch and glutelin at 100:0, 92:8, 75:25, 50:50 and 25:75 (w/w) were applied for casting film. Sorbitol was used as a plasticizer. Morphology was studied by scanning electron microscope. The mechanical properties and water vapor permeability (WVP) were evaluated. The results were found that rice starch and glutelin-based composite films became thinner with smoother surface as starch content increased. Elongation and flexibility of composite films containing glutelin could be improved by incorporation of rice starch at a considerable amount without affecting on tensile strength and WVP. Practical Applications This research had an objective to study the surface morphology, mechanical properties and WVP of composite films based on glutelin (by-products from producing rice starch) and rice starch. Those properties are important for the applications used as edible films/coatings. Edible films and coatings could be used to protect the product from mechanical damage, physical and chemical. In this paper, we did not add any antimicrobial agent. So, this film cannot protect the product from microbiological activities. The applications of edible films and coating have been successfully applied in fresh foods and processed foods.

Effects of Drying Temperature on the Properties of Deproteinized Natural Rubber Latex/Starch Composite Films

The aim of this study was to observe the effects of drying temperature on the properties of deproteinized natural rubber latex (DNRL)/starch composite films. These composite films were prepared by simple mixing and then drying at different temperatures of 50, 60 and 70°C. Various parameters such as types (potato, sago, bean, corn, tapioca, rice, and glutinous starches), amounts (5-20 part per hundred of rubber (phr)) and water-dispersed concentrations (5-50%) of starch blended were evaluated. It was found that only some DNRL/starch composite formulations could be prepared as the completely homogeneous films. Drying temperature affected the degree of starch gelatinization that confirmed by differential scanning calorimeter (DSC) technique. The DNRL composite films of 20 phr of all 7 starch types could be formed at 50 and 60°C, while those of 20 phr sago, bean, corn, and rice starch could be formed at 70°C. Some of these films were difficult to be the completely dry films at 70°C due to their more degree of gelatinization of starch on the surface films which inhibited the evaporation of water inside the films. However, only some DNRL/starch composites showed the homogeneous film under cross-section scanning electron microscopy (SEM) observations. Their compatibilities were confirmed by Fourier transform infrared spectroscopy (FT-IR) and DSC. Their physical and mechanical properties were further evaluated by the universal testing machine.