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Biodegradable polymers have emerged as a subject of enormous scientific and industrial interest due to their environmentally friendly compostability. For the benefit of the market economy and reoccurring environmental hazards, biodegradable materials should play a more critical role in packaging materials, which currently accounts for 60% of plastic products. However, various challenges remain for biodegradable polymers towards practical packaging applications. Particularly pertaining to the poor gas/moisture barrier issues which greatly limit the food packaging application of current biodegradable polymers. The chain architecture tailoring, crystallinity, melt blending/multi-layer co-extrusion, nanotechnology and surface coating have been considered as effective strategies for overcoming the poor gas/moisture barrier facing biodegradable polymers, which have been extensively researched for decades. In this review, we provide an in-depth study on the oxygen/water vapor barrier of representative biodegradable polymers in mainstream research with an emphasis on theoretical models and experimental modifications to improve their barrier properties. The influence of various strategies on the barrier improvement, and the pros/cons of each method are summarized. The limitations of current methods are discussed, and potential methods to overcome these limitations are presented. Finally, we conclude this review by listing current challenges associated with the barrier properties, processing and scalability of biodegradable polymers in the food packaging market, and future perspectives for these biodegradable polymers in sustainable composites field.

Summary Biodegradable food packaging promises a more sustainable future. Poly(lactic acid) (PLA) is a promising alternative for petroleum-derived polymers. However, PLA films suffer from poor barrier properties compared with petroleum-derived ones. To address this issue, we designed bilayer and sandwich-architectured trilayer films based on PLA and gliadin. We reported firstly the direct formation of PLA–gliadin bilayer/trilayer films without surface modification on PLA film. The films were compact and uniform, and double/triple layers were combined firmly, preventing delamination. This strategy enhanced mechanical resistance, ductility and moisture barrier of gliadin films and concomitantly enhanced the oxygen barrier for PLA films. Thymol loadings endowed bilayer/trilayer films with antimicrobial activity and antioxidant activity. The antimicrobial activity of the films depended on film types, and gliadin 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/trilayer architecture helping to create synergism of the biopolymers.

Temperature and moisture measurements were made in a ventilated attic on a house with 200 mm mineral wool insulation. The measurements showed that 1) solar radiation had a great effect on the temperature in the attic; 2) moisture content reached a level below the risk of mold formation – no mold was seen. The measurements were compared with simulations for insulation thickness from 50 to 500 mm. The calculations indicated that the temperature was nearly the same when the attic was insulated with 200 to 500 mm; hence increased insulation was not a problem. The important assumption was that the roof was constructed with a moisture barrier.

Popping of starchy pellets in a domestic microwave oven has proven difficult compared to pellets expanded in frying oil, and even to microwave expanded popcorn. These pellets encounter problems like uneven popping, burning and the absence of an audible cue for the end of popping. The lack of a moisture barrier, like the pericarp of popcorn, leads to the development of an inverse temperature gradient in the pellets and a significant moisture loss before and after expansion. In this paper we review the hypotheses and solutions for the criticality of microwave popping of starchy pellets, as discussed in scientific and patent literature. We have found a large collection of critical factors and their associated hypotheses, which have been structured via linking them to specific steps in the physical expansion process. We conclude with a list of hypotheses that we view valuable for further investigation.

We fabricated inorganic/organic composite film as encapsulation for top-emitting OLEDs, where the inorganic layer was composed of an Al2O3/MgO laminated structure prepared by atomic layer deposition (ALD), while the solution-processed polymer (CYTOP, PDMS and SU-8) was fabricated as the organic protective layer. It was found that the optimized inorganic/organic bi-layer structure has better barrier performance, leading to a superior water vapor transmission rate (WVTR) as low as 1.05 × 10−6 g m−2 day−1 at 60 °C and 100% R.H., and the encapsulated OLEDs device produces no black spots under a harsh environment (85 °C & 85% R.H.) for 250 h. These improvements were attributed to the hydrophobic surface of the capping polymer lowering the adsorption of water vapor into the bulk material.

Coconut oil constitutes the most important source of dietary fat in many countries. But, of late the consumption of coconut oil has been linked with incidence of coronary heart diseases and sustained campaign against its use is going on. Normal coconut oil contains 92% of saturated fatty acids, most of them are medium chain fatty acids (MCFA). The monoglyceride monolaurium is the substance that keeps infants from getting viral or bacterial or protozoal infections. Coconut oil lowers cholesterol through stimulation of thyroid function. Also coconut oil has high resistance to oxidative rancidity, sharp melting behavior, effective heat transfer agent in frying, provides moisture barrier and in frying, loss to bakery items in spray oil use, carrier and protective agent for fat soluble vitamins, maximum glycerin content, easily saponifiable even in cold, germicidal and antimicrobial property, ready penetration into the skin and appreciable water absorbing property.

Structural fire-protective clothing must be effective at minimizing the thermal effects of fire. However, water remaining on the outer shell might play an important role in conducting heat transfer, which causes skin burns in a firefighter when he douses a fire with water through a hose. Therefore, this research demonstrated the difference in the heat transfer and humidity created by the remaining water or lack of water on the outer shell under a condition in which the temperature (45 ± 1℃) of the external environment was higher than that of the skin. Two types of multilayered systems, which simulated real fire-protective clothing (outer shell, moisture barrier, thermal liner) were tested by using a human–clothing–environment (HCE) simulator. The experimental results verified that water on the outer shell increased the microclimate temperature in the structural fire-protective clothing. In particular, we assume that air permeability in the outer shell can be an important factor to control heat and mass transfer within the microclimate.

Semi fabricates based on Cu(In,Ga)Se 2 solar cells with flexible metallic substrate packaged in innovative moisture barriers that demonstrated failure after damp heat exposure were analyzed using thermographic imaging, luminescence imaging and optical microscopy. This made it possible to visualize and identify the failure modes and find explanations for the causes of failure. The most important causes of failure were concluded to be 1) the relaxation of stresses induced during lamination, 2) moisture ingress from the sides of the samples and 3) moisture ingress at positions where the barrier had been damaged due to the topology of the sample.

Due to the interest in health and concern for the environment, this review work was concentrated on biodegradable and edible materials for the agricultural sector. Edible polymers are recognized as safe for human consumption. In agricultural industry, a film coating is required to prolong the shelf life of products, since moisture plays a critical role in their stabilities. Materials used in film coatings include proteins, polysaccharides and lipids. Shellac is a lipid polymer of interest due to an outstanding moisture barrier and an abundant natural resource of Thailand. However, the shellac film has some drawbacks due to the polymerization and strength of film. This book chapter will focus on the current work to solve the drawbacks of shellac. The application of shellac for film coating in agricultural products, as well as the use of surface free energy for the prediction of coating efficiency was also reviewed in this chapter.

The test house with special timber structure was built by the department of rural building of Estonian University of Life Sciences. The hygrothermal properties of sawdust and cellulose, used as insulation materials in building envelope, were investigated in long term. The test was carried out during four winters. The wind and moisture-vapor barriers were not applied in the first testing period. In the second testing period the wall was covered inside with the moisture barrier and outside with the wind barrier and the layer of OSB plates. In wintertime the test house was heated with electric batteries to keep the indoors temperature stable. The aim of this research was to measure and determine the thermal transmittance of differently insulated wall sections. To fulfil the task the devices to measure relative moisture and temperature were placed in five different positions (in three depths inside the insulation) and indoors and outdoors. The heat flux plates were applied on the inner surface of the wall. Data were recorded with 10 min interval. The analysis of these test periods was carried out and presented in this paper.

Perovskite based photovoltaic (PV) devices have gained enormous importance due to their high power conversion efficiencies and ease of fabrication (solution processing). Conventionally, flexible solar cells have been reported on substrates like PET and PEN. Corning® Willow® Glass, owing to its superior processability and oxygen and moisture barrier property, is a potential replacement for these substrates. In this work, devices fabricated on Willow Glass substrates have been subjected to bending and fatigue tests to assess their worthiness as substrates for flexible solar cells.

Nanocellulose (NC) films are considered as a prospective alternative to non-sustainable packaging materials, however, their higher embodied energy and limited moisture barrier properties are regarded as a huge constraint regarding their commercialization. This study aims to produce films with relatively low environmental impact and improved barrier performance. For this purpose, carboxymethyl cellulose (CMC) and NC were combined, and this resulted in multidimensional advantages. The mass production of films could be achieved in only 2 h (requiring at least 24 h under ambient conditions) when dried in an oven at 75 °C with enhanced mechanical properties and without compromising their dimensional stability. The moisture barrier properties of the NC/CMC films were improved up to 92 % compared with the NC films alone and the results achieved are comparable with packaging materials such as polyethylene terephthalate (PET), polycarbonates (PC) etc. Finally, the NC/CMC (1:1) films have low environmental impact compared with PET films.

Atomic layer deposited nanolaminates of alternating AlOx and TiOx thin-films are investigated as moisture barriers for organic electronic devices. Direct encapsulation on organic light emitting diodes (OLEDs) is tested in aging experiments and compared to calcium corrosion tests of equivalent barrier films. This allows for a direct assessment of moisture barrier performance in simple as well as more complex systems. Thickness variations are performed for the nanolaminate single and total layer thickness, with an optimum single layer thickness of 1–2 nm observed. This correlates to the maximum number of dyads once completely closed single layers are produced. For large single layer thickness and low dyad count, strong lateral diffusion from the edges occurs in the OLEDs, which likely correlates to poor mechanical stability. At optimum single layer thickness, barriers remain mechanically and chemically stable up to 100 nm total thickness. OLEDs encapsulated with such nanolaminate barriers show no significant degradation after 2500 h of continuous aging.

Protection from steam burns is beneficial to reduce the nonfatal injuries of firefighters in firefighting and rescue operations. A new multifunctional testing apparatus was employed to study heat and steam transfer in protective clothing under low-pressure steam and low-level thermal radiation. Single-, double-, and triple-layered fabric assemblies were selected in this experiment. It is indicated that the existence of hot steam weakens the positive influence of the fabric’s thickness, but increases the importance of the air permeability on the thermal protection. The fabric assemblies entrapping moisture barrier can better resist the penetration of steam through the fabric system, and significantly improve the thermal protection in low steam and thermal radiation exposure due to the low air permeability. Additionally, the total transmitted energy ( Qe) and dry thermal energy ( Qd) under low steam and thermal radiation are dramatically larger than that under thermal radiation ( p 0.05). The understanding of steam heat transfer helps to provide proper guidance to improve the thermal protection of the firefighter’s clothing and reduce steam burns.

Integrated standardised methodology for biopolymer derivatives (BPD) production from novel intact bitter cassava was demonstrated by desirability optimisation of simultaneous release, recovery, cyanogenesis (SRRC) process. BPD were evaluated for yield and colour using buffer (0, 2, 4% v/v), cassava waste solids (15, 23, 30% w/w), and extraction time (4, 7, 10 min). Nearly all the root was transformed into BPD, with higher yield and colour in comparison to starch extrinsically processed. Maximum global desirability, predicted efficient material balance, buffer 4.0% w/v, cassava waste solids 23% w/w and extraction time, 10 min, producing BPD yield, 38.8% wb Validation using buffer, 3.3% w/v, cassava waste solids, 30% w/w and extraction time, 10 min, produced 40.7% wb BPD. SEM, DSC, TGA, FTIR and moisture barrier analyses revealed a uniform microstructure and high thermal stability of BPD and film, thus demonstrating efficient performance of the standardised integrated methodology. Hence, processing intact cassava root as a standardised integrated methodology could be used to produce sustainable low cost BPD for a broad range of applications. Methodologies designed around standard integrated procedures, matching zero-based approach to contamination, are novel strategies, and if used effectively can eliminate cassava wastes and recover BPD resources as sustainable biomaterials.

Herein, a novel thin-film encapsulation for flexible organic light-emitting diodes (FOLEDs) is proposed, and its long-term reliability in tensile stress conditions was tested. The hybrid nano-stratified moisture barrier consists of 2.5 dyads of an Al 2 O 3 /ZnO nano-stratified structure and a S-H nanocomposite organic layer. The nano-stratified structure is prepared by low-temperature atomic layer deposition and the S-H nanocomposite by spin-coating at a thickness of 30 and 120 nm, respectively. An optical transmittance of 89.05% was measured with the 2.5-dyad hybrid nano-stratified moisture barrier with a total thickness of 330 nm. A low water vapor transmission rate (WVTR) of 1.91 × 10 −5 g/m 2 day was recorded based on an electrical Ca test at 30 °C and 90% R.H. without losing its properties after a bending test. With this highly reliable hybrid nano-stratified moisture barrier, FOLEDs were successfully encapsulated. After 30 days under conditions of 30 °C and 90% R.H. with tensile stress, the J-V-L performances of the FOLEDs were comparable to those of the initial state without dark spots. These results suggest that this hybrid nano-stratified moisture barrier is an excellent method for encapsulating FOLEDs.

Firefighters are required to carry out their responsibilities under a wide range of environmental conditions. For this reason, the physiological and psychological responses of firefighters while wearing their protective clothing should be analyzed to minimize their thermal or cold stress. Four environmental conditions were selected: hot and humid (HH, 34℃, 75% relative humidity (RH)), hot and dry (HD, 34℃, 30% RH), warm and dry (WD, 27℃, 30% RH), and slightly cold (SC, –3℃). Six professional firefighters served as subjects. The exercise was performed on a treadmill at the maximum speed of 8 km/h. The microclimate temperature and RH, skin temperature, heart rate, oxygen uptake, sweat loss, sweat evaporation, moisture accumulation within the outer shell, moisture barrier and thermal liner, and subjective sensations were measured. The microclimate wet-bulb globe temperatures (micro-WBGTs) were calculated. High microclimate measures, skin temperature, and heart rate, as well as low scored subjective sensations, were observed under the HH condition. A 45% difference in RH between HH and HD resulted in clearer differential responses compared with the 7℃ difference in air temperature between HD and WD. Under the SC condition, subjects had a cool to cold feeling. A quite different distribution of moisture accumulation in clothing layers was observed under the SC condition compared with other conditions. This moisture accumulation affected the comfort sensation. A linear relationship was found between the comfort sensation and the micro-WBGT. The micro-WBGT was a good indicator of the physiological status of the wearers. The microclimate, moisture accumulation and its distribution within firefighters’ protective clothing should be extensively studied in the future.

In this study, an Mg-air battery based on air cathode with different content of Na2SO4 was prepared to study the effect of Na2SO4 on the performance of Mg-air battery. The electrochemical performance of the air cathode was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. The results indicated that the electrochemical activity of the electrode enhanced with the increasing Na2SO4. The discharge performance of the battery was investigated by constant-current discharge test, and the results showed that the discharge potential of the battery also improved with the increasing of Na2SO4. However, the forming of air cathode became difficult gradually with the increasing content of Na2SO4. What is worse, the oversize pore produced in the moisture barrier when the content of Na2SO4 was too high and the moisture barrier would lose resistance to water. So the content of Na2SO4 should not be too high.

Shelf-life of many foods is largely dependent on the barrier to moisture and oxygen of the respective package. Barrier is often assessed by measuring the transmission rate of films. However, in thermosealed packages leaks and weak seals can give rise to increased total mass transfer entering the system and reaching the food. While leaks are random defects and are associated to early failure, lower integrity of regular seals tends to affect whole batch causing a decrease in the product shelf-life. In the present work the contribution of the seals to total permeability of packages was assessed by measuring transmission rate of the film and of thermosealed packages of different sizes, therefore with different seals length. Packages made of PA/PE and PVDC coated PET/PE and their respective films were tested for moisture and oxygen transmission rate at different temperature and relative humidity. Results indicate that industrial regular produced seals can account for ca. 25% of the total mass transfer through the system. This decrease of the package barrier as compared to the material barrier will have a significant impact on the product shelf-life and it should be considered in the packaging design process.

Vapour-proof layer in roof envelope of residential attic has dominant position in terms of moisture regime. It has significant impact on quality and proper functioning of the remaining layers mainly the thermal insulation. The paper points out on the mounting defects in vapour-proof layer installations which occur chiefly due to poor realization during construction. The defects are often ignored, underestimated and their acceptance at earlier and later stages causes serious failures affecting the housing quality.

A finite difference model was introduced to simulate the transmitted and stored energy in firefighters' protective clothing exposed to low-level thermal radiation. The model domain consists of a three-layer fire-resistant fabric system (outer shell, moisture barrier, and thermal liner), the human skin, and the air gap between clothing and the skin. The model accounted for the relationship between the transmitted heat during the exposure and the discharged heat during the cooling-down period. The numerical model predictions were compared with experimental data. Additionally, the parameters that affect the transmitted and stored energy of protective clothing were investigated. The results demonstrate that for the typical multilayer firefighter protective clothing, the transmitted heat during exposure and the discharged heat after exposure totally determine the skin burn under low-level heat exposure, especially for third-degree skin burns. The findings obtained in this study can be used to engineer fabric systems that provide better protection for the stored thermal burn.

We propose an alumina-deposited double-layer graphene (2LG) as a transparent, scalable, and stretchable barrier against moisture; this barrier is indispensable for foldable or stretchable organic displays and electronics. Both the barrier property and stretchability were significantly enhanced through the introduction of 2LG between alumina and a polymeric substrate. 2LG with negligible polymeric residues was coated on the polymeric substrate via a scalable dry transfer method in a roll-to-roll manner; an alumina layer was deposited on the graphene via atomic layer deposition. The effect of the graphene layer on crack generation in the alumina layer was systematically studied under external strain using an in situ micro-tensile tester, and correlations between the deformation-induced defects and water vapor transmission rate were quantitatively analyzed. The enhanced stretchability of alumina-deposited 2LG originated from the interlayer sliding between the graphene layers, which resulted in the crack density of the alumina layer being reduced under external strain.

We report the effect of plasma parameters on the properties of ultrathin Al2O3 films prepared by plasma enhanced atomic layer deposition for moisture barrier applications. The Al2O3 films were grown at 90 °C using trimethylaluminum and O2 plasma as precursors. Plasma power, exposure time and O2 concentration are found to influence the growth behavior, composition and density of ultrathin Al2O3 films. Plasma power ≥ 100 W leads to lower impurity levels and higher mass densities of ∼2.85 g•cm-3. The optimum plasma parameters for our process, a plasma power of 100 W and an exposure time of 3 s, reveal a good water vapor transmission rate of 5 × 10-3 g•m-2•day-1 for polyethylene naphthalate substrates coated with 4 nm-thick Al2O3 films.

The text of the paper deals with the unusual use of textile membrane, originally used in outdoor clothing, as hydrobariers in building composites. In the experiment, the resistance of the building composite exposed to the 1.5 m high water column is examined. Research is conducted on two levels. On the first level, we focus on developing a building composite that includes a smart fabric membrane and is waterproof and vapour-permeable. On the second level, we deal with the development of a measuring system which will be able to correctly evaluate the water resistance of the building composite. A moisture-proof and air-permeable membrane can protect construction against various effects of moisture (i.e. flood, rain, ground water). The resulting water permeability values are compared with the four types of construction composite. It is discussed whether it is possible to create hydrobarriers in buildings if a textile nanofibrous membrane is composed into the building composite. If the composite is able to capture 70-80% of the water then the energy savings are significant.

This report describes the development and evaluation of prototype foam dispensing equipment, foam materials, and repair tactics, techniques, and procedures (TTPs) for rapid airfield damage repair (RADR) using foam backfill technology. Three different prototype foam dispensing systems were evaluated, two of which were developed in-house, along with foam products from two vendors and different repair methods and techniques to improve the TTPs for foam backfill technology. Results from full-scale field testing showed that the top performing prototype system was a hose pump system, and the top performing foam material was Foam-iT! 10 Slow. Plastic liners were a successful technique for a moisture barrier to ensure the quality of the repair material. Foam cutting methods, such as scarfer and reciprocating saw, were good options; how-ever, both methods have safety concerns and add time and manpower to the repair process. Overall, the technology proved to be effective in meeting RADR requirements. Repair times were comparable to those of the standard flowable fill backfill method. Repair performance under simulated F-15E aircraft traffic was satisfactory. All repairs met the 2-hr requirement of 100 passes and the expedient repair requirement of 500 passes. Only one repair met the RADR requirement of 3,500 passes.

Structure ignition by wind-driven firebrand showers is an important fire spread mechanism in large outdoor fires. Experiments were conducted with three common mulch types (shredded hardwood mulch, Japanese Cypress wood chips, and pine bark nuggets) placed adjacent to realistic-scale re-entrant corners. In the first series of experiments, mulch beds were placed adjacent to a re-entrant corner constructed with wood studs and lined with oriented strand board (OSB) as the sheathing. The premise behind conducting experiments with no siding treatments applied was predicated on the notion that bare OSB mulch contact would be a worst-case scenario, and therefore, a wall assembly in the most vulnerable state to mulch ignition. In the second series of experiments, vinyl siding was applied to the re-entrant corner assemblies (wood studs/OSB/moisture barrier/vinyl siding), and the influence of vertical separation distance (102 mm or 203 mm) on wall ignition from adjacent mulch beds was determined. The vertical separation distance was maintained by applying gypsum board to the base of the re-entrant corner. The siding itself did not influence the ignition process for the mulch beds, as the mulch beds were the first to ignite from the firebrand showers. In all experiments, it was observed that firebrands produced smoldering ignition in the mulch beds, this transitioned to flaming ignition, and the re-entrant corner assembly was exposed to the flaming mulch beds. With no siding treatments applied, the flaming mulch beds ignited the re-entrant corner, and ignition was observed to propagate to the back side of re-entrant corner assembly under all wind speeds (6 m/s to 8 m/s). With respect to the re-entrant corners fitted with vinyl siding, the mulch type, vertical separation distance, and wind speed were important parameters as to whether flaming ignition was observed to propagate to the back-side of a re-entrant corner assembly. Mulches clearly pose an ignition hazard to structures in large outdoor fires.

The water vapor barrier properties of low-temperature atomic layer deposited (ALD) AlOx thin-films are observed to be unstable if exposed directly to high or even ambient relative humidities. Upon exposure to humid atmospheres, their apparent barrier breaks down and their water vapor transmission rates (WVTR), measured by electrical calcium tests, deteriorate by several orders of magnitude. These changes are accompanied by surface roughening beyond the original thickness, observed by atomic force microscopy. X-ray reflectivity investigations show a strong decrease in density caused by only 5 min storage in a 38 °C, 90% relative humidity climate. We show that barrier stabilities required for device applications can be achieved by protection layers which prevent the direct contact of water condensing on the surface, i.e., the sensitive ALD barrier. Nine different protection layers of either ALD materials or polymers are tested on the barriers. Although ALD materials prove to be ineffective, applied polymers seem to provide good protection independent of thickness, surface free energy, and deposition technique. A glued-on PET foil stands out as a low-cost, easily processed, and especially stable solution. This way, 20 nm single layer ALD barriers for organic electronics are measured. They yield reliable WVTRs down to 2×10(-5) g(H2O) m(-2) day(-1) at 38 °C and 90% relative humidity, highlighting the great potential of ALD encapsulation.

The synergy between fast (1600 nm · min−1), roll-to-roll plasma-enhanced chemical vapor deposited (PE-CVD) SiO2 layers and plasma-assisted atomic layer deposited (PA-ALD) ultra-thin Al2O3 films has been investigated in terms of moisture permeation barrier properties. The effective and intrinsic water vapor transmission rates (WVTR) were studied as a function of the number of ALD cycles. It was demonstrated that a synergistic combination of a silica buffer layer deposited on polymer with an ultra-thin (≤ 2 nm) alumina barrier film can provide excellent intrinsic (10−5–10−6 g · m−2 · day−1) and good effective (∼10−3 g · m−2 · day−1) WVTR values, whereas both single layers individually exhibit poor barrier performances with effective WVTR values of ≥ 1.0 g · m−2 · day−1.

In this work the combination of ellipsometric porosimetry (EP) and electrochemical impedance spectroscopy (EIS) is extensively addressed in order to characterize the nano-porosity and further elucidate its influence on the water permeation properties of plasma enhanced-CVD SiO2 layers. Pores with diameter in the range of 0.27–0.6 nm are studied by adopting a multi-solvent/multi-ion approach, with EP and EIS, respectively. This combined study has brought to conclude that open pores larger than 0.42 nm are responsible for WVTR values in the range of 10−3-10−5 gm−2 day−1, while pores with diameter between 0.42–0.27 nm were found to drive the transition to excellent moisture barrier layers (10−6 gm−2 day−1). Moreover, it is shown that EIS is capable of detecting macro-scale defects, next to nano-porosity, being thus a powerful tool for the analysis of moisture barrier layers.

We have developed high throughput and scalable space divided atomic layer deposition (ALD) system for thin filmencapsulation (TFE) of flexible OLEDs display. In this paper, we report high moisture barrier properties of Al2O3 films deposited by our new developed high throughput (70 A/min) spatial ALD with 2G glass substrate size (370 × 470 mm2). The WVTR on flexible substrate could achieve ∼10−5 g/m2-day under tritium test.