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Summary With amazing progress in the state-of-the-art perovskite solar cells (PSCs) fabricated by laboratory-scale spin-coating methods, upscaling the PSCs via printing friendly techniques is becoming more and more important toward the future deployment of large-scale and stable perovskite modules. Here, we demonstrate the room-temperature meniscus coating of high-quality perovskite films incorporated with a multifunctional sulfobetaine-based zwitterionic surfactant. Systematic in situ studies uncover the perovskite crystallization pathway and emphasize the surfactant’s synergistic role in film construction, crystallization kinetics modulation, defect passivation, and moisture barrier protection. This strategy is applicable across perovskite compositions and device architectures with the enhanced power conversion efficiencies up to 22%. Upscaling the device area to 0.8 cm2 has negligible deterioration in the performance. This represents one of the highest records for the upscaling coated PSCs, not limited in room-temperature coated PSCs. In addition, this approach significantly improves the stability of perovskite films and devices under different aging conditions.

A polyorganosiloxane thin film was deposited on an optically transparent poly(ethylene 2,6-naphthalate) (PEN) film using plasma-enhanced chemical vapor deposition (PECVD) at room temperature to imp...

This paper presents the effect of process parameters of twin screw extruder and addition of Cloisite-15A on mechanical, thermal and moisture barrier properties of epoxy/Cloisite-15A nanocomposites. Four lobed kneading blocks were used the in shearing zone of the extruder, based on their effectiveness in dispersing nanofillers in epoxy. Screw speeds from 100 min−1 to 400 min−1, number of passes up to 15, temperature from 5°C to 80°C and Cloisite-15A contents from 1 wt.% to 2.5 wt.% were considered for designing the L12 Orthogonal Array. Improvements in tensile strength, compression strength, flexural strength, impact strength, hardness and moisture diffusivity in the nanocomposites were 11.89%, 20.06%, 27.73%, 37.26%, 25.48% and 56.22% respectively, when compared to neat epoxy. The improvements were achieved for screw speed of 400 min–1, 5 passes through the extruder, processing temperature of 5°C and 2 wt.% of Cloisite-15A. Dispersion of Cloisite-15A in epoxy was studied by XRD, SEM and TEM. Thermal stability and moisture barrier properties were superior in the nanocomposites.

Interactions between midlatitude westerlies and the Pamir–Tian Shan mountains significantly impact hydroclimate patterns in Central Asia today, and they played an important role in driving Asian aridification during the Cenozoic. We show that distinct west-east hydroclimate differences were established over Central Asia during the late Oligocene (ca. 25 Ma), as recorded by stable oxygen isotopic values of soil carbonates. Our climate simulations show that these differences are present when relief of the Pamir–Tian Shan is higher than 75% of modern elevation (∼3000 m). Integrated with geological evidence, we suggest that a significant portion of the Pamir–Tian Shan orogen had reached elevations of ∼3 km and acted as a moisture barrier for the westerlies since ca. 25 Ma.

Barrier film coating is the most appropriate and widely used approach to protect solid dosages from moisture, particularly for water-sensitive drugs including herbal medicines. This study aims to produce the barrier film of a typical herbal medicine by applying an electrostatic deposition process with ultrafine powders of hydroxypropyl cellulose so as to achieve the functionality of moisture protection. The flowability of the ultrafine powders was significantly improved by adding suitable nano additives. The applied plasticizer in the coating formulation had a significant effect on the water vapor permeability of the film. Also, the electrostatic deposition efficiency were significantly affected by the charging voltage of the electrostatic gun and the plasticizer ratio. Curing time and temperature were identified as two critical parameters for barrier coating in terms of surface morphology and hygroscopicity. All the results suggested that the electrostatic deposition process is capable to produce efficient barrier film for herbal medicines.

A structure of flexible glass/flexible transparent conducting electrode (TCE) comparable with the conventional glass/indium tin oxide (ITO) substrate is proposed by combining an Ag NW + PEDOT:PSS hybrid TCE (h‐TCE) with triple‐layer a‐SiNx:H/n‐SiOxNy/h‐SiOx ultrahigh barrier (UHB) films. The UHB films have dual functions of both moisture barriers with a water vapor transmission rate (WVTR) of 1.6 × 10−5 × g m−2 day−1 and antireflection (AR) with a gradient refractive index. Flexible PTB7:PC70BM‐based organic photovoltaics (OPVs) with the AR‐UHB film achieve a maximum power conversion efficiency (PCE) of ηmax = 8.33%, saturation current density (Jsc) of 17.67 mA cm−2, and external quantum efficiency (EQE) of 63.3%, which are higher than ηmax = 7.63%, Jsc = 15.25 mA cm−2, and EQE = 59.26% of the OPVs on glass/ITO. These result from the increase in the absorption of the donor PTB7 due to the AR effect of the UHB films. A long‐term stability of the AR‐UHB encapsulation layer in damp heat (40 °C/85% relative humidity [RH]) is confirmed by the result that the measured T80 and T50 values for the OPV device on glass/ITO encapsulated with the AR‐UHB film are about 1008 h (42 days) and 2205 h (92 days), respectively.

Baked food products are considered to be one of the most popular processed foods in the world. Among all the bakery products, biscuits are the most frequently consumed snack food item. There is a vast and diverse market for biscuits as a leader in ready-to-eat baked goods. Biscuits have long shelf life than other bakery products when stored under proper conditions. But immediately after exposure to the air by opening or damaging the package, biscuits absorb moisture from the air and reduce its crispiness of the biscuits. According to the market survey results, the highest number of respondents (53.7 %) suggested developing an edible coating for biscuits to prevent the loss of crispiness in biscuits upon storage. As well as 98.5 % of respondents prefer edible coatings developed using natural sources. Polysaccharide-based edible coatings maintain the physicochemical, microbiological & sensorial properties of the food. Therefore, okra mucilage was used as the main ingredient for edible coating preparation for biscuits. The coating was applied on biscuits with different coating methods, different baking stages and stored in different environmental conditions to identify the efficiency of the coating. According to the results, a coating applied before the baking stage displayed better moisture barrier properties than that of the coating applied after baking in controlled, semi-controlled, and normal atmospheric environmental conditions. It's responsible for the reduction of moisture absorption of biscuits upon storage

As the demand for flexible, rollable, and foldable displays grows, various state-of-the-art component technologies, including thin-film transistors (TFTs), electrodes, thin-film encapsulations (TFEs), and touch screen panels, have been developed based on organic light-emitting diodes (OLEDs) with flexible organic layers. Developing highly reliable flexible OLEDs is essential to realize flexible displays, but the flexible encapsulation technology still has technical difficulties and issues to be addressed. This review covers the recent developments in encapsulation technologies, particularly their material and structural designs, for highly reliable, flexible OLEDs. The solution concepts for the existing technical hurdles in flexible encapsulations are addressed. Among the various advanced flexible encapsulation technologies developed so far, neutral-axis engineering with a thin metal layer and a crack arrester is introduced.

Municipal firefighters count on their protective garments to avoid skin burns caused by thermal and flame exposures. Typical firefighting garment consists of three layers of different fire-resistant fabrics named as outer shell, moisture barrier and thermal liner. This paper employed a numerical heat transfer model for firefighters’ garments, which paid more attention to modeling air gaps bounded between garment’s layers. The paper explored and compared the influences of air gaps bounded between garment’s layers on its protective performance. Specifically, the paper investigated the effect of a variation in the air gaps between the garment layers from 1 mm to 6 mm, a variation in the backside emissivity of the outer shell and moisture barrier layers from 0.9 to 0.1 and a variation in their typical thicknesses from 50% to 200% on the protective performance of garment. The results showed that increasing the width of the gap between the moisture barrier and the thermal liner, reducing the outer shell backside emissivity and increasing the moisture barrier thickness improves the protective performance of firefighters’ garments more than does increasing the width of the gap between the moisture barrier and outer shell, reducing the moisture barrier backside emissivity and increasing the outer shell thickness, respectively.

The use of clay filler materials in dispersion coatings is a well-established method to provide improved barrier properties to the coated paper substrate, in particular lowering the water vapour transmission rate (WVTR) through the coating. In this paper we demonstrate the use of small spherical silica particles (∼100–220 nm) as an additive to a clay-latex coating formulation is able to provide further improvements to the barrier properties, when compared to the equivalent silica-free coatings. A significant decrease in both the water vapour transmission rate and the direct water uptake of water ( Cobb 120 {\text{Cobb}_{120}} wettability test) is observed for coatings containing as little as 1 % silica additive.

In this study, we developed the universal encapsulation method using poly(vinyl alcohol-co-ethylene) (EVOH) to improve the water stability of perovskite solar cells. In order to enhance the moisture barrier property, we utilized SiO2 and graphene oxide (GO) fillers in the EVOH matrix. First, UV-treated SiO2 increased the dispersibility in the EVOH matrix and made the penetrating path more complicated, which led to a better moisture barrier property. The water vapor transmission ratio (WVTR) is enhanced from 4.72 × 10-2 (EVOH only) to 1.55 × 10-2 (EVOH with SiO2 filler) g/m2 day. Second, we found that GO reduce the unreacted hydroxyl groups that could attract water molecules at the surface of EVOH. The addition of GO increased the WVTR up to 3.34 × 10-3 g/m2 day. Finally, our EVOH-based film successfully encapsulated without the efficiency drop. The encapsulated devices surprisingly maintained 86% of their performance even under direct contact with water for 5 h.

This review article critically presents a comprehensive overview of the current advances in the research and development of proteins derived bionanocomposites used in food packaging applications. The recent interest in protein-based biomaterials is due to sustainability, renewability, biodegradability and low carbon footprint. The inherent drawbacks of proteins-based materials for food packaging applications are their low mechanical strength, poor thermal, barrier and inferior physicochemical properties. The nanoreinforced bio-based polymers called bionanocomposites provide an opportunity to overcome these issues and have ability to supersede non-biodegradable food packaging plastics produced from petroleum resources. So far, most studied protein derived bionanocomposites suitable for food packaging are soy protein isolates (SPI) and gelatin proteins. Layered silicates are the most promising nanofillers used to increase strength, improve heat resistance and enhance barrier properties of proteins derived materials while montmorillonites (MMT) is the most commonly used silicate nanofiller. This review emphases on the processing strategies used for proteins-based biomaterials, their mechanical and moisture barrier properties for food packaging applications. Different proteins and nanofillers that have been studied to date in proteins derived food packaging applications are also discussed in detail.

Thin film encapsulation (TFE) is one of the key problems that hinders the lifetime and widespread commercialization of flexible organic light-emitting diodes (OLEDs). In this work, TFE of OLEDs with Al2O3/alucone laminates grown by atomic layer deposition (ALD) and molecular layer deposition (MLD) as moisture barriers were demonstrated. The barrier performances of Al2O3/alucone laminates with respect to the individual layer thickness and the number of dyads were investigated. It was found that alucone with suitable layer thickness could reduce the permeation to the defect zones of the inorganic layer by prolonging the permeation pathway, sequentially improving the moisture barrier performance. The water vapor transmission rate (WVTR) could be further lowered with increasing the number of dyads of the laminates, the WVTR value reached 1.44 × 10−4 g per m2 per day for laminates with 5.5 dyads. These laminates were incorporated in OLEDs with pixel define layer (PDL), and were found to be able to evidently prolong the lifetime of the OLED.

We report the development of a class-II-type hybrid coating (NS-EP hybrid) composed of surface-modified nanosilica (NS) as the filler and a thermo-curable epoxy polymer (EP) as the matrix. NS is synthesized using a hydrolytic sol-gel process; its hydroxyl surface is rendered cross-linkable using glycidyl ligands to ensure homogeneous dispersion and optimal hybridization with the EP matrix. The NS-EP hybrid shows high optical transparency, enhanced mechanical properties, and improved moisture barrier performance. Further, we discuss the physical properties of the hybrid with respect to the NS content. To study the applicability of the hybrid as a high-performance barrier material in practical applications, an actual OLED device is encapsulated using the hybrid.

In this work, we employ atomic layer deposition (ALD) to form Al2O3 layer as an encapsulant for perovskite solar cells (PSCs). Al2O3 layer deposited at temperature as low as 95 °C achieves water vapor transmission rate (WVTR) of 1.84 × 10−2 g m−2 d−1 at 45 °C–100%RH when thermal ALD is used. In order to test the moisture barrier capability of Al2O3 layer for PSCs, mesoporous perovskite devices, with spiro-OMeTAD or PTAA as hole transport layer (HTM) encapsulated by 50 nm Al2O3 film, are exposed to 65 °C–85%RH for 350 h and their stabilities are monitored. We find that the color of perovskite does not change after 350 h of exposure regardless of the type of HTM used. With regards to Th-ALD encapsulated devices, PTAA based PSCs experienced a smaller power conversion efficiency (PCE) drop than spiro-OMeTAD based PSCs after thermal stress at 65 °C. This is due to the presence of pinholes within spiro-OMeTAD layer after thermal stress which are not observed in PTAA. Finally, we successfully achieve excellent durability test results for mesoporous (HC(NH2)2PbI3)0.85(CH3NH3PbBr3)0.15/PTAA devices encapsulated by 50 nm Al2O3 with less than 4% drop in PCE after 7500 h (> 10 months) of exposure to 50%RH under room temperature.

Geosynthetics materials are having wide application in Geotechnical Engineering field. It is available in different forms and can be applied as per the different functions like separator, lining, barrier, filter, reinforcement, etc., in various application area of Geotechnical Engineering field. One of the application of Geosynthetics material in pavement construction as a separator and/or moisture barrier enhances the performance of pavement. In this study the strength parameter of woven coir mat, Jute mat, and geomembrane was analyzed through CBR (California Bearing Ratio) test. In this study, soil aggregate system was used in the CBR mold with and without the geosynthetics material. The soaked and unsoaked CBR value of geotextile and geomembrane was determined and found that their application in the pavement construction can be very effective.

Background Rapid dissolution in digestive tract and moisture sorption during ambient storage are the two challenges of dry probiotic preparations. To solve these problems, microcapsules with shellac (LAC) addition containing Limosilactobacillus reuteri TMW 1.656 were designed in this work to provide a good moisture barrier and to provide controlled release in digestive tract, based on the hydrophobicity and acid-resistance of LAC. Four microcapsules were prepared using the method of emulsification/external gelation based on the crosslinking reaction between alginate or LAC with calcium ion, including alginate/sucrose (ALG), alginate/shellac/sucrose (ALG/LAC), alginate/whey protein isolate/sucrose (ALG/WPI) and alginate/whey protein isolate/shellac/sucrose (ALG/WPI/LAC). Results Measurements of physical properties showed that microcapsules with LAC addition (ALG/WPI/LAC and ALG/LAC) had larger particle size, much denser structure, lower hygroscopicity and slower solubilization in water, which agreed with the primary microcapsule design. Probiotic survivals in digestive juices followed the order of ALG/WPI/LAC ≥ ALG/WPI ≥ ALG/LAC > ALG. Probiotic stability after heating and ambient storage both exhibited the order of ALG/WPI/LAC > ALG/LAC ≈ ALG/WPI > ALG, which can be explained by the decreased hygroscopicity with adding LAC. Conclusion LAC addition contributed to better probiotic survivals after freeze drying, simulated digestion, heating and ambient storage, and whey protein isolate (WPI) addition had a synergistic effect. Microcapsule hygroscopicity was closely related with probiotic survivals after heating and ambient storage, while microcapsule solubilization was closely related with probiotic survivals in simulated juices. Within our knowledge, this is the first report to improve probiotic stability during ambient storage based on LAC hydrophobicity. © 2020 Society of Chemical Industry.

Barrier layers for the long-term encapsulation of implantable medical devices play a crucial role in the devices&rsquo, performance and reliability. Typically, to understand the stability and predict the lifetime of barriers (therefore, the implantable devices), the device is subjected to accelerated testing at higher temperatures compared to its service parameters. Nevertheless, at high temperatures, reaction and degradation mechanisms might be different, resulting in false accelerated test results. In this study, the maximum valid temperatures for the accelerated testing of two barrier layers were investigated: atomic layer deposited (ALD) Al2O3 and stacked ALD HfO2/Al2O3/HfO2, hereinafter referred to as ALD-3. The in-house developed standard barrier performance test is based on continuous electrical resistance monitoring and microscopic inspection of Cu patterns covered with the barrier and immersed in phosphate buffered saline (PBS) at temperatures up to 95 &deg, C. The results demonstrate the valid temperature window to perform temperature acceleration tests. In addition, the optimized ALD layer in combination with polyimide (polyimide/ALD-3/polyimide) works as effective barrier at 60 &deg, C for 1215 days, suggesting the potential applicability to the encapsulation of long-term implants.

Violin varnishes are known to affect both moisture absorption and vibrational properties of violin wood. However, traditional multi-layered varnish systems suffer from substantial wear as a result of intensive use, which calls for deeper understanding of the specific impact of individual layers. Using sophisticated in-situ neutron imaging and vibrational modal analysis, we show how wood sorption and vibrational behavior of tonewood depend on the build-up of the varnish system. The results demonstrate the protective effect of complete coatings and emphasize that strongly worn regions cannot accomplish the function as an effective moisture barrier, which might pose a risk for frequently played or aged string instruments. Furthermore, the build-up of the varnish system affects the vibrational properties of the tonewood, influencing its final sound quality. This delicate interplay should be considered both for the handling of antique and aged violins and for the production of modern high-quality instruments., Scientific Reports, 9, ISSN:2045-2322

This paper proposes a new method to determine the baking time for moisture-sensitive packages prior to dry pack. The concept is based on consideration of the continuous drying process for a package within moisture barrier bags (MBB), which contain a desiccant. If the moisture is not completely dried out during bake (usually at 125°C), the residual moisture will continue to diffuse out of the package body during storage and shipment in the MBB. In this paper, a 2.5D package is used for a worst-case scenario simulation through finite element modeling. It shows that after a 24hr bake at 125°C, the residual moisture weight gain remains 13% of the total saturated weight gain, and the maximum moisture concentration remains as high as 40% of the saturated moisture concentration; however, after 4 weeks of storage at 30°C in the MBB the residual moisture weight decreases to less than 1%, and the maximum saturated moisture concentration decreases to less than 5% of the saturated moisture concentration. Depending upon package construction, storage conditions and storage time before customer opening of MBB, the modeling results show that consideration of moisture diffusion in the MBB may permit the bake schedule to be shortened.

Purpose The purpose of this study is to review the recent approaches in food packaging trends to address the preferences of the modern world. Design/methodology/approach Recent studies in all the emerging food packaging technologies have been discussed with the examples of commercially available products. Findings Advanced food packaging solutions have acquired much appreciation from food industries to address the preferences of the modern world. This paper attempts to describe the current practices in food packaging with examples of commercially available products. Significant emphasis has been given on the technical aspects of the intelligent packaging components, namely, barcodes, radio frequency identification, sensors and indicators. Another distinctive area of packaging focused in this review is the importance of bioplastics due to non-degradable nature of synthetic polymers. Three major categories of biodegradable polymers, namely, polysaccharide-based materials, protein-based materials and lipid-based materials, have been discussed along with an insight about sustainable packaging and edible films and coatings. Originality/value Changes in the industrial & retail matters and increasing demand for fresh, safe, nutritious food are the factors owing to the new innovations in the packaging sector. Imminent packaging technologies aim at value addition involving the extension of shelf life, prevention of microbial attack, proper moisture barrier, use of carbon dioxide scavengers/emitters, ethylene scavengers, flavor absorbers, freshness indicators, biosensors and release of bioactive compounds during storage.

We report the facile fabrication of transparent and high-performance moisture barrier material (SC nanocomposite) using surface-modified bentonite clay (SC) as nanofiller and glycidyl silane as a surface-modifier/binder via simple, cost-effective and mass-producible process. SC is synthesised using a base-catalysed sol-gel process; their hydroxyl surfaces are decorated with glycidyl ligands to endure the densely stacked structure and high clay content in the final nanocomposite. The SC nanocomposite barrier exhibits high optical transparency (>90), dense multi-stacked clay structure, and considerably enhanced moisture barrier performance. We discuss the fabrication and physical properties of the SC nanocomposite. To assess the applicability of the nanocomposite as a high-performance barrier material in practical applications, typical organic light-emitting devices are encapsulated, and their lifetime is evaluated.

Biodegradable food packaging is sustainable and has a great application prospect. PLA is a promising alternative for petroleum-derived polymers. However, PLA packaging suffers from poor barrier properties compared with petroleum-derived ones. To address this issue, we designed bilayer films based on PLA and Pickering emulsions. The formed bilayer films were compact and uniform and double layers were combined firmly. This strategy enhanced mechanical resistance, ductility and moisture barrier of Pickering emulsion films, and concomitantly enhanced the oxygen barrier for PLA films. Thymol loadings in Pickering emulsion layer endowed them with antimicrobial and antioxidant activity. The release profile of thymol was well fitted with Fick's second law. The antimicrobial activity of the films depended on film types, and Pickering emulsion layer presented larger inhibition zone than PLA layer, hinting that the films possessed directional releasing role. This study opens a promising route to fabricate bilayer architecture creating synergism of each layer.

Applications of cellulose nanomaterials (CNMs) have attracted increasing attention in recent years. One conceivable path lies in their commercial applications for packaging, in which their barrier properties will play an important role in determining their competiveness with conventional materials. This review critically analyzes the performance of CNMs acting as a barrier against moisture and oxygen permeation in CNM films, CNM-coated polymers and papers, and CNM-reinforced polymer composites, gives some insights into remaining challenges, and brings an overall perspective of compositing CNMs with other materials to achieve balanced properties adequate for barrier packaging. In general, CNMs are a poor moisture barrier but excellent oxygen barrier in the dry state and are still good below 65% relative humidity. The addition of CNMs can improve the oxygen barrier of the resulting polymer composites; however, neat CNM coatings and films can afford better oxygen barrier properties than dispersed CNMs in coa...