Blend Films Research Articles

Synergistic direct and indirect central unit fluoridation of non-fullerene acceptor enables high-efficiency organic solar cells

The fluorination strategy for non-fullerene acceptors (NFAs), involving direct and indirect fluorination such as trifluoromethylation, has been established as an effective method to improve the power conversion efficiencies (PCEs) of organic solar cells (OSCs). Although end-group fluorination has achieved significant success, the fluorination of central units in NFAs has received limited exploration owing to the lack of substitution sites in conventional Y-series acceptors. To systematically investigate the effect of different central unit fluorination strategies on molecular stacking and subsequently the performance of OSCs, we utilized recently developed phenazine (CH)-series acceptors to design a series of NFAs, namely CH-F, CH-CF, and CH-FCF, which are featured with central unit mono-fluorination (CH-F), mono-trifluoromethylation (CH-CF), and synergistic fluorination and trifluoromethylation (CH-FCF), respectively. Among them, CH-FCF-based blend films (PM6/CH-FCF) demonstrate strengthened molecular interactions and crystallinity, an excellent fibrillar network morphology and bettered charge generation/transport performance. Consequently, the binary OSCs based on CH-FCF achieved the best PCE of 18.41 %, which outperforms its counterparts based on CH-F (17.34 %) and CH-CF (17.62 %). These results emphasize the significance of synergistically regulating the central unit of small molecule acceptors through different fluorination strategies to manipulate molecular packing and thus enhance the photovoltaic performance of OSCs.

Structural, optical, and thermal studies of Poly(vinylidene fluoride-co-hexafluoropropylene) and Polyvinylpyrrolidone composite doped Ag/ZnO mixed nanoparticles for flexible optoelectronic devices

Polymer nanocomposites (PNCs) films based on Polyvinylidene fluoride co-hexafluoropropylene (PVDF-HFP), Polyvinylpyrrolidone (PVP), and Ag/ZnO nanoparticles have been prepared using solution casting technique. Investigation of prepared films has been created using various experimental techniques. These prepared films were characterized by XRD, FTIR, UV–visible, and DSC/TGA analysis to study their structural, optical, and thermal properties. The Enhanced amorphous nature of PVDF-HFP/PVP blend film due to doping has been identified from X-ray diffraction analysis. The FTIR spectra confirmed the complexation between the Ag and ZnO ions and the host polymer in terms of changes in intensity and certain band positions. The UV–visible analysis showed that the optical band gap (direct and indirect band gap) of the pristine polymeric blend change significantly with the concentration of dopant Ag/ZnO NPs, and these effects are more noticeable at the higher loading. Variation in glass transition temperature (Tg) and melting temperature (Tm) of PVDF-HFP/PVP-Ag/ZnO PNCs system having various concentration of Ag/ZnO NPs were observed by DSC analysis. The Tg of the composite has been found to be decreasing with increase in the content of Ag/ZnO NPs revealing the ordered arrangement of nanoparticles in the blend. The excellent thermal stability of the blend nanocomposite compared to pure PVDF-HFP/PVP blend and its improvement with the loading of Ag/ZnO NPs has been proved by TGA. From all the characterization results, Ag/ZnO-doped PVDF-HFP/PVP polymer blend exhibits better properties which are more suitable for electrochemical devices.

Resilient and Tough Conductive Polymer Hydrogel for a Low-Hysteresis Strain Sensor.

Conductive polymer hydrogels are vital in strain sensors, yet achieving high resilience and toughness is a challenge. This study employs a prestretch method to engineer a tough conductive polymer hydrogel with sufficient resilience. Initially, a blend film of polyvinylalcohol (PVA) and ethylene-vinyl alcohol copolymer (EVOH) is prepared through solution casting, followed by a swelling process to form a PVA-EVOH hydrogel. This hydrogel, with PVA crystallites as crosslinking points, exhibits high toughness. The hydrogel is then immersed in pyrrole and ferric chloride solutions for in-situ polymerization of polypyrrole (PPy), creating a conductive PPy/PVA-EVOH hydrogel. Finally, a 200% prestretch is applied, breaking short chains within the network, eliminating energy dissipation at low strains. This results in a hydrogel with a 100% elastic deformation range, while maintaining high fracture toughness (1700Jm-2 ). The prestretched PPy/PVA-EVOH hydrogel functions as a strain sensor with low hysteresis, providing consistent strain measurements during loading and unloading. This outperforms the non-prestretched sample, which shows inconsistent responses between stretching and releasing.

Preparation and Properties of Immiscible Poly(lactic acid)/Ethyl Cellulose Bioplastic Blends with Good Transparency and Optical Control by Drawing

In this study we prepared a poly(lactic acid)/ethyl cellulose (PLA/EC) bioplastic blend film by melt pressing after solvent casting and investigated the optical, thermal, and mechanical properties in relation to the structural changes revealed by various microscopies and scattering measurements. Despite the immiscibility of PLA and EC, the blend film exhibited good optical transparency due to the close match in their refractive indices. A second run of differential scanning calorimetry during heating revealed a decrease in the glass transition temperature () and melting point () of PLA with EC although EC had the higher values. Thermomechanical analysis suggested that these decreases were due to the negative pressure generated due to the suppression of PLA shrinkage below and above during cooling. Furthermore, ductile drawing of the blend film (70/30) at an optimal temperature of 70 °C above resulted in a uniform whitening near 100% strain. Delamination at the interface between the PLA matrix and EC domain led to the formation of micrometer-sized oriented voids, which enhanced the refractive index difference in the phase-separated structure, thereby scattering light and achieving the uniform and oriented white blend film.

Sulfite incorporated thermoplastic cassava starch blended PBAT blown films as antimicrobial and antibrowning packaging

Microbial growth and browning cause quality loss in intermediate moisture foods. This research developed and characterized novel active films to prevent microbial growth and brown discoloration in dried meat and fruits. Biodegradable films based on thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate) (PBAT) blends incorporating sodium metabisulfite (SM) (up to 7% w/w) were developed using blown film extrusion. SM interacted with the TPS phase, involving O-H stretching vibration and hydrogen bonding which modified the thermal degradation behavior of the TPS phase and improved the smoothness of the film microstructures. Excessive SM formed crystal particles at ≥ 3% that were detected by X-ray diffraction. Addition of SM decreased the mechanical properties but film clarity and hydrophobicity improved, with enhanced water vapor barrier properties. The SM blend film showed significant antibacterial activity against E. coli, B. cereus, and S. aureus. TPS/PBAT/SM active films effectively prevented mold growth and darkening in packaged salami for at least 16 days, while the non-SM blend film was only effective for 6 days at room conditions. Active films with SM loading, particularly at > 3% prevented browning reaction and darkening in dried bananas and longans at both ambient (60% RH) and 85% RH stored at room temperature. SM addition improved packaging characteristics and functional efficiency, resulting in higher dried fruit and meat product quality. TPS/PBAT/SM composite films showed promise as sustainable active packaging and an alternative technique to sulfite treatment for dried fruit and meat.

Promoting antibacterial activity of polyurethane blend films by regulating surface-enrichment of SiO2 bactericidal agent

Abstract Polyurethane (PU) blended with nano-bactericidal agents was one of the most ways to obtain PU with antimicrobial properties. However, the bactericidal agent nanoparticles cannot effectively enrich the PU surface to reduce their antimicrobial properties. In this study, nano-silica particles with a large number of polar quaternary ammonium salt (N,N-dimethyl-3-aminopropyl-12-alkyl-ammonium bromide trimethylsilyl, denoted as QAC) can easily enrich the PU surface to endow PU with excellent antibacterial properties after they were blended with PU film. The QAC on the surface of silica with different diameters (denoted as SiO2-Q-X) can endow silica with antimicrobial properties and improve the repulsion between silica and PU to enhance the enrichment on PU surface of silica. A series of SiO2-Q-X/PU blend films were prepared and applied to inhibit the growth of the bacterial colony. The SiO2-Q-X/PU films can inhibit the growth of Gram-negative Escherichia coli and Gram-positive Staphylococcus epidermidis. The SiO2-Q-X with more polar QAC was easily enriched on the surface of PU and had a better bactericidal effect than those of SiO2-Q-X with a minor polar QAC. Moreover, the aging of the SiO2-Q-X/PU films did not affect their antibacterial effect.

Effect of ε-Polylysine Addition on Pullulan Biodegradable Films for Blueberry Surface Coating

A biodegradable film was successfully prepared using pullulan and ε-polylysine (ε-PL). The impact of ε-PL contents on biodegradable film was explored through mechanical properties, water vapor permeability, and an FTIR spectroscopy test. Amongst all the prepared films, the 0.5% ε-PL had the most desirable results in film performance. The TS, EAB, and WVP values were 5.63 MPa, 21.5%, and 0.27 × 10−6 g m/Pa h m2, respectively. The blueberries coated with 0.5% ε-PL and pullulan were stored at 20 °C for 12 days. The effect of edible coatings on the performance of blueberries was evaluated by detecting the physicochemical properties and the contents of antioxidants. The experimental results displayed that ε-PL and a pullulan blend film could decrease the weight loss and maintain the hardness, polyphenol, anthocyanin, and antioxidant capacity of the blueberry preservation. The results indicated that the biodegradable film is a potential fruit-coating material.

Recent Advances in Functional Cellulose-based Films with Antimicrobial and Antioxidant Properties for Food Packaging.

The packaging of food plays a crucial role in food preservation worldwide. However, traditional packaging systems are passive layers with weak efficiency in protecting the food quality. Therefore, packaged foods are gradually spoiled due to the oxidation and growth of microorganisms. Additionally, most of the commercial packaging films are made of petroleum-based materials which raise environmental concerns. Accordingly, the development of eco-friendly natural-derived active packaging systems has increased the attention of scientists. Cellulose as the most abundant polysaccharide on earth with high biocompatibility, no toxicity, and high biodegradability has extensively been applied for the fabrication of packaging films. However, neat cellulose-based films lack antioxidant and antimicrobial activities. Therefore, neat cellulose-based films are passive films with weak food preservation performance. Active films have been developed by incorporating antioxidants and antimicrobial agents into the films. In this review, we have explored the latest research on the fabrication of antimicrobial/antioxidant cellulose-based active packaging films by incorporating natural extracts, natural polyphenols, nanoparticles, and microparticles into the cellulose-based film formulations. We categorized these types of packaging films into two main groups: (i) blend films which are obtained by mixing solutions of cellulose with other soluble antimicrobial/antioxidant agents such as natural extracts and polyphenols; and (ii) composite films which are fabricated by dispersing antimicrobial/antioxidant nano- or microfillers into the cellulose solution. The effect of these additives on the antioxidant and antimicrobial properties of the films has been explained. Additionally, the changes in the other properties of the films such as hydrophilicity, water evaporation rate, and mechanical properties have also been briefly addressed.

Structural, optical, and dielectric characteristics of chitosan/hydroxypropyl cellulose‐modified copper vanadate nanoparticles

AbstractChitosan (Cs) and hydroxypropyl cellulose (HPC) blend films were created and incorporated with copper vanadate nanoparticles. The films were characterized using various techniques, including x‐ray diffraction (XRD), attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR), TEM, SEM, UV/vis spectroscopy, dielectric properties, and AC conductivity. The XRD analysis showed that the prepared films had amorphous characteristics. FT‐IR spectra indicated interactions between the Cs/HPC virgin polymers and copper vanadate nanoparticles. TEM analysis showed that the most prevalent size range of the nanoparticles was 20–60 nm. SEM micrographs revealed surface homogeneity at lower copper vanadate nanoparticle contents but increased inhomogeneity with higher contents. The prepared films showed a decrease in the optical energy gap and an increase in refractive index with increasing copper vanadate nanoparticle content. Copper vanadate nanoparticles enhance AC conductivity in Cs/HPC polymer blend. Dielectric analysis proved the suitability of the films for electroactive polymer applications.Highlights The casting process was used to prepare Cs/HPC—copper vanadate NPs films. XRD shows increased amorphousness post‐addition of copper vanadate NPs. SEM images revealed an increase in inhomogeneity with higher contents of copper vanadate NPs. The optical band gap decreased as the content of copper vanadate NPs increased. Copper vanadate nanoparticles greatly improve electrical conductivity and relaxation time.

Exploring the Potential of Roselle Calyx and Sappan Heartwood Extracts as Natural Colorants in Poly(butylene Succinate) for Biodegradable Packaging Films.

Recently, there has been a growing concern among consumers regarding the safety of packaging products, particularly due to the presence of potentially harmful substances like synthetic pigments and inorganic dyes. These substances, which are often used to attract consumer attention, can migrate and contaminate products over extended shelf storage periods. To address this issue, the focus of this research was the development of a biodegradable packaging film using poly(butylene succinate) (PBS) incorporated with natural colorants extracted from roselle (RS) and sappan heartwood (SP). RS and SP serve as non-toxic and alternative pigments when compared to synthetic colorants. The biodegradable packaging films were prepared using blown film extrusion, encompassing different weight percentages of RS and SP (0.1%, 0.2%, and 0.3%). The films exhibited distinct colors, with RS films appearing pink to purple and SP films exhibiting an orange hue. The water vapor transmission rate slightly decreased with an increasing content of RS and SP extracts, indicating improved barrier properties. Additionally, the films showed reduced light transmittance, as evidenced by the UV-Vis light barrier results. The degree of crystallinity in the films was enhanced, as confirmed by X-ray diffraction and differential scanning calorimetry techniques. Regarding mechanical properties, the PBS/RS and PBS/SP films exhibited slight increases in tensile strength and elongation compared to neat PBS films. Moreover, the blended films demonstrated higher stability after undergoing an aging test, further highlighting their potential for use in biodegradable packaging applications. The key advantages of these films lie in their non-toxicity, biodegradability, and overall environmental friendliness.

Fluorenyl-based polyurethane efficiently improves the flexibility and photovoltaic performance of organic solar cells

Introducing proper insulating polymer in the active layer can improve the photovoltaic and mechanical properties of organic solar cells. Here, we design and synthesize a polyurethane insulating material K-BA20 (or 50) containing PDMS and 2D aryl block 9,9-diphenyl-9H-fluorene (DPF). Isophorone diisocyanate (IPDI) is selected as the connection unit and hydrogen bond is introduced to reduce the chain slippage caused by excessive one-dimensional structure. This strategy can enhance the adhesion between components, which can successfully improve the photovoltaic performance and mechanical properties of the devices. When 5 and 15 wt% K-BA20 was introduced into the PM6:Y6-based system, the short-circuit current density (JSC) of 26.71 and 26.65 mA cm−2, and the power conversion efficiency (PCE) of 16.67% and 16.05% were obtained. More interestingly, the active layer introduced K-BA20 with low DPF ratio has good stretchable properties, while K-BA50 with high DPF ratio has more stable flexibility. The breaking elongation of the blend film with introducing 15 wt% K-BA20 was increased 3.2-fold, from 5.81% to 18.46%, and the PM6:Y6-based flexible devices after doping 5 wt% K-BA50 can still maintain half of the initial efficiency under 600 bending fatigues. Hence, this work shows that introducing K-BA20 (or 50) into PM6:Y6 -based devices can bring out a series of positive feedbacks in terms of charge recombination, crystallinity and molecular interaction. It can be seen that constructing new insulating polyurethane materials with rigid and flexible segments is an effective strategy for development of flexible organic solar cells.

Introducing thiazole units into small-molecule acceptors for efficient non-fullerene organic solar cells

The end-group modification engineering has been widely applied in non-fullerene acceptors (NFAs) to achieve high-performance organic solar cells (OSCs). Herein, we designed and synthesized a series of small-molecule acceptors (SMAs), namely ODTz-γ, ODTz-m, DTTz-γ and DTTz-m, which containing the electron-withdrawing thiazole units on the end groups at different position. These SMAs not only exhibited strong and broad absorption region from 500 nm to 900 nm, identical band gaps, but also the similar energy levels, indicating the position of thiazole units have trivial effect on their absorbance and energy levels. OSCs were fabricated by integrating an electron-donating polymer PBDB-T with these resultant electron-accepting materials. Devices based on ODTz-γexhibited an obviously higher power conversion efficiency over 12.0%, which outperformed those of obtained from devices based on other SMAs. Further characterization of the devices revealed that introducing the thiazole units into the γ position of end groups can enhance the charge transport mobility, suppress recombination, and improve the blend film morphology.

Morphology and Mechanical Properties of Poly(vinyl alcohol)/Poly(lactic acid) Blend Films Prepared from Aqueous Dispersions

AbstractIn this study, the preparation of poly(vinyl alcohol) (PVA)/poly(lactic acid) (PLA) blends of different compositions, 100/0, 75/25, 50/50, 25/75, and 0/100, by mixing water solutions of the former and water dispersions of the latter polymer, is reported. Two distinct dispersions of PLA are prepared using a commercial‐grade polyester and two different surfactants, an anionic one and a neutral one. Films of PLA and of the corresponding blends are obtained by simply drying at 60 °C the water dispersions without or with the PVA. The films are characterized by infrared spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscope (SEM) analysis. This evidences an island‐like morphology, with the continuous phase consisting of a PVA rich phase at all compositions except 25/75, for which an inverted phase composition, with a continuous phase made mostly of PLA, is instead found. Voids caused by air bubbles trapped in the initial mixture are observed in particular in the formulations with the anionic surfactant. The trapped bubbles result in premature thermal degradation by thermogravimetric analysis (TGA) and mechanical failure during clamping. Films with the neutral stabilizer are tougher than the bare commercial PLA, with Young modulus and elongation at break depending on the combination of the composition and arrangement of blend phases.

Study of alkali-soluble curdlan/bacterial cellulose/cinnamon essential oil blend films with enhanced mechanical properties

In response to the growing demand for biodegraded film with high mechanical properties for complex preservation application scenarios, we developed a curdlan (CD) blended films with exceptional mechanical strength through an alkali dissolution method. Notably, the alkali-soluble CD film exhibited five-fold increase in tensile strength (TS) when compared to its water-soluble counterpart. Furthermore, the inclusion of 2 % bacterial cellulose (BC) resulted in a significant 41.1 % augmentation of the film's TS. Thermal stability improvements were observed through differential scanning calorimetry (DSC) analysis and thermogravimetric analysis (TGA). X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) results provided insights into alterations in film crystallinity and intermolecular interactions. Specifically, the incorporation of 10 % CEO led to an additional improvement in TS. Our experimental investigations involving the packaging of chilled fresh meat with these blended films unveiled their capacity to effectively inhibit microorganism growth, maintain meat color stability, delay protein decomposition and fat oxidation, and extend the storage time up to 9 days. Our study offers a promising solution for food packaging, emphasizing the development of a high-strength degradable CD/BC/CEO blended film, which holds potential for extending the shelf life of food products.

Tuning the energy storage performance of graphene oxide-based nanocomposite films by encapsulating silver nanoparticles

In the current designed study, we explore the dielectric and energy storage performance of silver nanoparticle decorated graphene oxide nanocomposites incorporated into chitosan blended with poly (1-vinylpyrrolidone-co-vinyl acetate) in comparison with only graphene oxide nanocomposite doped into the same blend matrix. A sustainable and eco-friendly green route approach was used to form the silver nanoparticle decorated graphene oxide nanocomposites. The nanocomposite films so fabricated using the solvent evaporation method, were subjected to various characterisation techniques such as X-ray diffraction analysis, Fourier transform infrared spectroscopy, thermal analysis, surface morphology and impedance spectroscopy. Slight decrease in crystallinity (44.3 %), difference in the positioning of infrared bands, thermal stability (up to ∼77 °C) and evenly distributed morphology depict the advantage of silver coating over graphene oxide nanoparticles in the blended nanocomposite films. A boost in the dielectric properties and energy storage ability was displayed by the silver encapsulated graphene oxide reinforced nanocomposite blend films. The dielectric properties were examined by using a Nyquist plot (Bulk resistance - 1.01 × 104 Ω). An ionic conductivity of 1.044 × 10−4 S/cm and a DC conductivity of 1.196 × 10‐−4 S/cm was observed. Of note, it can be inferred that silver nanoparticle decorated graphene oxide nanocomposites impart tremendous electrical properties to the chitosan/poly (1-vinylpyrrolidone-co-vinylacetate) films, enabling them to be used in energy storage applications.

Characterization, antioxidant and antibacterial activities of chitosan/flaxseed soluble dietary fiber/sesamol blend films and their application in pork preservation

Chitosan (CS)-based functional films have been widely used in food packaging and preservation. In this work, we incorporated the sesamol and flaxseed soluble dietary fiber into chitosan solution to make blend films and investigated their mechanical and physicochemical properties, their antioxidant and antibacterial activities as well as their application in pork preservation. The physicochemical properties including optical properties, water solubility (WS), swelling degree (SD), water vapor transmission rate, and mechanical properties were measured. Meanwhile, the effects of flaxseed soluble dietary fiber (fSDF) and sesamol (Sol) on the microstructure of the blend film were further explored using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis. Thereafter, the antioxidant and antibacterial capabilities of CS-based films were evaluated. Moreover, the quality changes, myoglobin, and lipid oxidation during the storage period of fresh pork wrapped with CS-based films were monitored. The results showed that the incorporation of fSDF significantly changed the relatively regular and dense interaction network of CS film itself, which resulted in an improved elongation at break and UV resistance, reduced tensile strength, water resistance, and barrier functions. The addition of sesamol filled up the gaps caused by fSDF and had a smoother and denser structure. Therefore, CS/fSDF/Sol had a better barrier function and water resistance. Besides, sesamol addition significantly increased the antioxidant and antibacterial capabilities. Especially, compared with sesamol-incorporated CS films, sesamol-blended CS/fSDF films exhibited greater antioxidant and antibacterial activities. Finally, when three films (CS, CS/fSDF, CS/fSDF/Sol1.2) were used in the preservation of fresh pork, the CS/fSDF/Sol1.2 exhibited the best performance with the least changes in the appearance, odor, pH values, lipid and myoglobin oxidation levels, and the bacterial contamination. However, the water loss during storage did not improve significantly in pork even coated with CS/fSDF/Sol1.2. In conclusion, we suggest the co-addition of fSDF and sesamol into chitosan films to enhance their functionality in preservation.

Assessment of thermal, crystalline and morphological properties of ellagic acid incorporated PVA, chitosan, PVA/chitosan and PVA/chitosan/gaur gum polymeric films

In the present study, the ellagic acid doped Polyvinyl alcohol (PVA), Chitosan (CS), PVA/CS and PVA/CS/Guar-gum blend films were prepared and coded as EA-1, EA-2, EA-3 and EA-4, respectively. The physicochemical properties of prepared films were analyzed by using different instrumental techniques. The differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) results revealed the good interaction and miscibility among the components of the films. The thermal stability of ellagic acid incorporated PVA film (EA-1) shown more thermal stability in contrast with other films confirmed by thermogravimetric analysis (TGA) analysis. From the results of X-ray diffraction (XRD) study, the increased amorphous nature was observed for the EA-3 and EA-4 films. Surface morphology was analyzed by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) which illustrates that prepared films exhibits smooth and homogeneous surface after blending with ellagic acid. The results obtained by measuring water contact angles (WCA) revealed that all the films have hydrophilic nature. All the prepared films have exhibited good mechanical properties, hence prepared films can act as promising material for food packaging application.

Polymer Packaging through the Blending of Biowaste Oyster Shell and Low-Density Polyethylene: A Sustainable Approach for Enhanced Food Preservation.

This research delves into the impact of incorporating thermally treated oyster shell powder (TOS), a biowaste filler, into low-density polyethylene (LDPE) to develop a LDPE/TOS blend, aiming at enhancing food packaging materials. The LDPE/TOS blend portrays advantageous characteristics such as augmented mechanical strength, thermostability, crystallinity, water absorption, and improved hydrophobicity with TOS content up to 50%. Microstructure analysis reveals a transition from a sparse to a more interconnected structure, contributing to the amplified tensile strength. The blend demonstrates increased barrier properties against water vapor transmission, which is attributed to elongated diffusion paths induced by the TOS particles. Application of the blend material in vegetable preservation trials manifested a substantial reduction in water loss compared to pure LDPE or no packaging. This biowaste-based blend film extends the shelf-life of chicken significantly when compared to that of pure LDPE. Importantly, the LDPE/TOS blend exhibits excellent antibacterial properties against both Escherichia coli and Staphylococcus aureus.

Beeswax: A review on the recent progress in the development of superhydrophobic films/coatings and their applications in fruits preservation.

Recently, the design and fabrication of bio-inspired superhydrophobic materials using natural lipid additives such as beeswax (BW) have aroused great attention in food packaging as they can minimize the transfer rate of water molecules and have effective moisture barriers. This review discusses the recent progress in the design and fabrication of BW-containing edible films/coatings (e.g., emulsion and blend films, bilayer materials, bionanocomposites, and antimicrobial materials) and their potential applications on the postharvest life and quality attributes of various fruits. Incorporation of BW into polysaccharides- and proteins-based emulsion films effectively improved their hydrophobicity, water vapor, and UV/visible light barrier properties, as well as the film tensile properties. The addition of nanoparticles to BW-based polymeric matrices often results in improved physico-mechanical properties. BW coatings have been also applied to prolong the shelf-life of various climacteric fruits, however, optimization of the wax concentration can be further investigated to develop targeted food storage systems.

Preparation of silver nanoparticles on free-standing polyaniline/cellulose acetate blend film for surface-enhanced Raman scattering application

Preparation of silver nanoparticles on free-standing polyaniline/cellulose acetate blend film for surface-enhanced Raman scattering application