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| Polymeric materials | Methods and formulation | Effect on barrier properties | References |
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| Cellulose and derivatives | A natural formulation composed of carboxymethyl cellulose (CMC) and various contents of cellulose nanocrystals immobilized silver nanoparticles (CNC@AgNPs) was developed for paper coating. | The water vapor and air barrier properties of CMC/CNC@AgNPs coated paper improved with the increasing content of CNC@AgNPs. CMC/CNC@AgNPs 7% coated paper exhibited 45.4% decrease in water vapor permeability (WVP) and 93.3% reduction in air permeability. | [121] |
| Nanofibrillated cellulose (NFC) was prepared from microcrystalline cellulose via a high-pressure homogenization process and deliberately employed as a coating agent. | Water retention value (WRV) decreased from 250.0 to 158.71 g/m2 when 0.40% NFC was added. The WVP exhibited a decrease from 27.50 to 25.0 g/m2 at 0.30% NFC and further to 24.0 g/m2 at 0.40% NFC. | [120, 122] |
| Solutions of the synthesized cellulose stearoyl ester compound were coated onto the calendered paper sheets by bar coater with the coating grammage ranging from 0.5 to 23.6 g m−2. | Contact angle values increased from ≈15 to 109 ± 2°. Water vapor transmission rates (WVTR) values declined from 514.80 to 27.74 g m−2 d−1. The barrier ratio of coated paper to uncoated paper was recorded as >90% | [120, 123] |
| Multilayered hybrid thin films of cellulose nanocrystals (CNC) and gibbsite nanoplatelets built by layer-by-layer technique onto substrates selected for packaging applications. | The measurement of the oxygen transmission rate (OTR) at 23°C and 50% RH showed that the oxygen barrier properties of the bare substrates could be significantly improved. Specifically, there was a substantial improvement, with the OTR experiencing a significant decrease of approximately 75% following the application of these thin (<100 nm) multilayered hybrid films. | [124] |
| An aqueous slurry base, a mixture of cellulose nanofibrils and nanoclay particles, was sprayed on a kraft writing and printing paper surface as base substrate. Upon drying, the suspension on the paper surface formed a hybrid nanocomposite layer with cellulose nanofibrils (matrix) and nanoclay (mineral filler). | WVTR reduced from 28.55 ± 0.7 to 4 ± 0.2 (g m−2 day). OTR values were not improved because of the incomplete closure of the base paper. | [125] |
| Cellulose nanofibers (CNF) were used as a coating to improve the structure and barrier properties. Two forms of CNF were used: refiner-produced material and material produced with an ultra-fine grinder. CMC was used for some samples as an additive. | CNF significantly enhanced the barrier properties of the coated papers. Gravimetric water retention values declined with an increase in solid content from 1.5% to 3%. Air resistance increased from 80 to 1,400 Gurley s. | [126] |
| Nanocomposite films prepared from TEMPO-oxidized nanofibrillated cellulose isolated from rice straw, chitosan nanoparticles, and glycerol by solution casting. The percentage of chitosan nanoparticles ranged from 2.5% to 20% while a fixed ratio of glycerol (25%) was added. | WVP increased by 15%, water absorption reduced by 33% (Cobb test), and oil penetration time increased from 6 to 78 s. | [127] |
| Handsheets were coated on one side with 1.5 or 3 wt% cellulose nanofibils as a single or double layer. | A double layer of 1.5 wt% cellulose nanofibils resulted in better barrier properties compared to a single layer of 3 wt% cellulose nanofibils, even though the total amount of applied cellulose nanofibils was the same. | [128] |
| Microfibrillated cellulose coated using bar coating process. 2% microfibrillated cellulose suspension was applied on cardboards using bar coating (5 cm). The process was repeated five times to deposit five layers. | Microfibrillated cellulose did not enhance much cardboard barrier properties, although it considerably increases their water absorption from 43 ± 7 to 114 ± 7 g/m2. KIT values increased from 0 to 2.5 ± 0.5. | [129] |
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| PLA and derivatives | PLA films incorporated with cinnamic acid (3 wt%) using casting and thermal processing. | O2 permeability decreased from 187 ± 8 to 141 ± 2 × 1014 · cm3/m·s·Pa, while WVP decreased from 0.28 ± 0.06 to 0.18 ± 0.11 g · mm/kPa·h·m2 | [120, 130] |
| A synthetic, large aspect ratio Na-Hectorite is used that may be utterly delaminated in an organic solvent and composited with PLA by modification with 18-crown-6 (18C6Hec), yielding a castable, homogeneous nematic suspension. | O2 permeability was reduced from 17,775 cm3 μm m−2 day−1 atm−1, which was reduced by 99.3% to 124 cm3 μm m−2 day−1 atm−1 and swelling properties in freshwater were decreased. | [120, 131] |
| Pure potato starch was modified by 3-APTMS (3-(aminopropyl) trimethoxy silane) to manufacture a cross-linked film. To obtain a bilayer PPS-3APTMS-PLA film, the PLA was employed with PPS-3APTMS by casting method. | WVP improved from 31.69 ± 0.4 × 10−7 g s−1 m−1 to 14.26 ± 0.3 × 10−7 g s−1 m−1. | [120, 132] |
| PLA/polyethylene glycol (PEG)/graphene oxide composite films with filler concentration, relative to PLA, restricted up to 2 wt%, while 10 wt% of PEG was used as a plasticizer. | O2 permeability decreased from 1.45 × 10−14 to 1.05 × 10−14 (kg m (m2 s Pa)). while WVP decreased from 3.42 × 10−18 to 2.18 × 10−18 (kg m (m2 s Pa)) | [120, 133] |
| Polyester multilayer membranes with more than 2,000 alternating layers of PLA and PBS were prepared via a nanolayer coextrusion process equipped with a multiplying-element device. | Improvement in barrier performances until 30% for oxygen, 40% for water and 70% for carbon dioxide. | [134] |
| Melt extrusion was used to plasticize PLA with 5% epoxidized karanja oil. | O2 permeability increased from 20.9 ± 0.9 to 25.4 ± 1.2 (cm3 mm m−2 day−1), while WVP increased from 71.2 ± 1.0 to 74.1 ± 0.7 (θw). | [120, 135] |
| Coproducts coming from mill industries, such as wheat gluten proteins (WG), were used to produce PLA-WG-PLA multilayer complexes with improved barrier performance. | The most efficient complex increased more than 20 times (or 2,000%) the barrier properties to oxygen and ∼20% the barrier properties to water vapor, considering application conditions (50% relative humidity and 25°C). | [136] |
| Zinc oxide nanoparticles (ZnO NPs) were synthesized using zinc chloride and NaOH and they were incorporated to prepare PLA/ZnO NPs composite films. | WVP decreased by 30.5% from 3.11 × 10−11 to 2.16 × 10−11 g m/m2·Pa·s when 0.5 wt% of ZnO NPs was incorporated. | [137] |
| Bleached bamboo kraft pulp was pretreated by 2,2,6,6-tetramethylpiperidine-1-oxy radical- (TEMPO-) mediated oxidation using a TEMPO/NaBr/NaClO system at pH = 10 in water to facilitate mechanical disintegration into TEMPO-oxidized cellulose nanofibrils (TO-CNs). | O2 permeability drastically decreased from 355 for neat PLA to 8.4 mL · m–2 · d–1 after coating a thin layer of TO-CN with a carboxylate content of 1.8 mmol · g–1. | [138] |
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| PBS and derivatives | Poly(butylene adipate-co-terephthalate), poly(butylene succinate), and linear low-density polyethylene were blended to produce bio-based packaging via blown-film extrusion. | O2 permeability was significantly reduced in films containing PBS, and WVP was reported to be 1.5 g mm/m2 · d·k·Pa. | [139] |
| PBS/Graphene nanoplatelets (GnP) nanocomposites over a range of GnP from 0 to 1.35 wt%. were prepared by a melt process. A mixture of individual graphene nanosheets and aggregates was obtained by the addition of GnP in the PBS matrix. | Water permeability improved by 38% and dioxygen permeability by 35%. | [140] |
| Biofilms made of poly PBS and tapioca starch (TPS) added with 1.5% or 3% of Biomaster-silver particles were made. | Small pore-size features with high barrier property for gas permeability were obtained for BM-filled PBS/TPS films. The O2 permeability decreased from 28.650 to 17.420 cm3 μm/m2 s Pa, while WVP increased from 90.17 to 95.40 g μm/m2 with the incorporation of TPS. | [141] |
| PBS/poly (butylene adipate-co-terephthalate films (containing 25%, 50%, and 75% PBS (w/w))). | O2 permeability decreased from 4.41 ± 0.01 to 0.68 ± 0.01 × 1016 mol/m−1 · s−1 · Pa−1, while WVP decreased from 7.09 ± 0.08 to 2.90 ± 0.02 × 10−12 mol/m s Pa. | [120, 142] |
| Bio-nanocomposite films were prepared using PBS as a matrix and banana starch nanocrystals (SNC) as filler by chill-roll cast film extrusion. | WVTR and OTR values of 9% wt modified SNC/PBS film (54.1 g m−2 day and 216.3 cc m−2 day) were lower than those of neat PBS film (114.5 g m−2 day and 560.3 cc m−2 day) | [143] |
| PBS composite films with lactic acid through slit die extrusion–stretching–woven compression molding. In situ nanofibrillar networks of PLA are constructed within a PBS matrix serving as an efficient “barrier ball” and reinforcement. | Gas permeability of composite films decreased significantly, i.e., >63% reduction in PO2 from 5.8 × 10−15 to 2.1 × 10−15 cm3 cm−2 s−1 Pa−1. | [120, 144] |
| A confined flaking technique was used to establish the degradable nanolaminar PBS in PLA films based on PLA/PBS in situ nanofibrillar composites. The combination of high pressure (10 MPa) and temperature (160°C) during the flaking process enabled sufficient deformation of PBS nanofibrils and retention of ordered PLA channels. | O2 permeability decreased by 87%, i.e., from 1.4 to 0.6 × 10−14 cm3 · cm · cm−2 · s−1 · Pa−1. | [120, 145] |
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| PHA and derivatives | Combination of PHA-based materials and nanokeratin extracted from poultry feathers. | O2 permeability decreased from 1.75 ± 0.25 to 0.90 ± 0.05 × 10 − 19 m3 · m · Pa−1 · s−1 · m−2 and WVP decreased significantly from 3.54 ± 0.40 to 1.22 ± 0.10 × 10−14 kg m s−1 m−2 Pa−1. | [120, 146] |
| Organic recyclable high-oxygen-barrier multilayer films based on different commercial PHA materials, including a blend with commercial poly(butylene adipate-co-terephthalate), which contained an inner layer of cellulose nanocrystals and an electrospun hot-tack adhesive layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) derived from cheese whey. | O2 permeability decreased from 57.81 ± 21.45 to 1.12 ± 0.61 × 10 − 19 m3 · m · Pa−1 · s−1 · m−2, while WVP decreased significantly from 11.47 ± 0.06 to 0.82 ± 0.03 × 10−11 kg m s−1 m−2 Pa−1. | [120, 147] |
| An electrospun antimicrobial hot-tack layer made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) derived from cheese whey was deposited on a blown film of commercial food contact PHA-based resin. A hybrid combination of oregano essential oil and zinc oxide nanoparticles was incorporated during the electrospinning process into the PHBV nanofibers at 2.5 and 2.25 wt%, respectively. | WVP decreased from 3.22 ± 0.12 to 0.87 ± 0.92 × 10−11 kg · m−2 · Pa−1 · s−1. | [120, 148] |
| Enhanced thermoplastic corn starch nanobiocomposites containing bacterial cellulose nanowhiskers (BCNW) prepared by melt mixing were made. | Improved barrier to water vapor and oxygen at high relative humidity (80%) was observed, reaching the best performance at 15 wt% BCNW loading with a maximum drop of 46% and 95% for water and oxygen permeability. | [149] |
| Three-layer films based on plasticized wheat gluten films have been developed by applying a more hydrophobic electrospun PHA layer on both sides of the protein film. A commercial PHB and a polyhydroxybutyrate-co-valerate copolymer with 3% valerate content (PHBV3) have been used. | O2 permeability decreased from 15.10 ± 2.42 to 4.36 × 10−15 m3 · m · Pa−1 · s−1 · m−2, and WVP decreased from 16.02 ± 0.43 to 3.11 ± 0.64 × 10−11 kg · m · Pa−1 · s−1 · m−2. | [120, 150] |
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