Moisture and Oxygen Barrier Properties of Cellulose Nanomaterial-Based Films

Abstract

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 coatings and nanocomposites. The morphology and surface functionality of CNMs can be tailored to maximize the barrier performance of materials comprising them. The higher the surface charge density is of CNMs, the better is the barrier performance of coated polymers. Like other oxygen barriers such as ethylene vinyl alcohol and cellophane, the moisture sensitivity and sealability of CNMs can be improved by sandwiching them with high moisture-resistant and sealable polymers such as a polyolefin. A multilayered structure with layers of CNMs providing oxygen resistance covered by other layers of polymers providing moisture resistance and sealability might be competitive in barrier packaging markets dominated by synthetic plastics.

Transparent lignin-containing wood nanofiber films with UV-blocking, oxygen barrier, and anti-microbial properties

“…62 The results presented in Table 2 indicate that at an RH of 50%, the oxygen barrier properties (OP values) of CWNF lms can be described either as high (#400 cm 3 mm (m 2 d atm) À1 ) or medium (400-4000 cm 3 mm (m 2 d atm) À1 ). 63 The results indicate that CWNFs are signicantly better oxygen barriers than the hydrophobic synthetic polymers used in packaging materials. 63 Nevertheless, their OP values are higher compared to efficient oxygen barriers, such as polyvinylidene chloride (10-300 cm 3 mm (m 2 d atm) À1 ) 64 and lms produced from CNFs at an RH of 50%.…”

A Brief Review of Nanocellulose Based Hybrid Membranes for CO2 Separation

“…Wang et al summarized studies of applying nanocellulose for gas barrier application [85]. Similar results were obtained for different nanocellulose: they could work as excellent oxygen barrier materials at the dry state and the performances are still good at low relative humidity (<65%), but they are a poor moisture barrier.…”

Mechanical and Permeability Properties of Thermoplastic Starch Composites Reinforced with Cellulose Nanofiber for Packaging Applications

“…Sustainable food packaging has a substantial impact on quality, taste, and marketability of products. As per the WHO, approximately 40% of all food products spoil every year in the United States (Wang et al, 2018). Limitations in harvesting, transporting and storage all contribute to this spoilage.…”

“…Oxygen Transmission Rate (OTR) measurements of representative films were evaluated as the most important parameters for these properties (Wang et al, 2018).…”