Layer-by-Layer Assembly of Polysaccharide Films with Self-Healing and Antifogging Properties for Food Packaging Applications

Abstract

Self-healable, transparent, and antifogging polysaccharide films composed of acrylamide-modified chitosan (AMCS) and alginate aldehyde (ADA) were fabricated via layer-by-layer (LBL) assembly. The Schiff base linkage formed between amino groups of AMCS and aldehyde groups of ADA was used to construct the films. Fourier transform infrared spectroscopy and X-ray photoelectron spectra revealed that the films were cross-linked through Schiff base bonds. Ultraviolet− visible spectroscopy and field emission scanning electron microscope characterizations demonstrated that the films exhibited linear growth during the LBL process. The films showed a repetitive self-healing property, and the repeated damage-healing of the films was thickness-dependent. The films can heal the scratches that penetrated to the underlying substrates. Besides the excellent self-healing property, the films showed an antifogging property due to the hydrophilic nature of the two polysaccharides. The antifogging ability of the film was thickness-dependent. Also, the films could regain their transmittance and fog-resistant property after mechanical abrasion due to their self-healing capability. These self-healable and fog-resistant polymeric films have potential applications in food packaging.

Crosslinkable‐Chitosan‐Enabled Moisture‐Resistant Multilayer Gas Barrier Thin Film

“…This naturally‐occurring polysaccharide has received a great deal of attention because of its primary amine and hydroxyl functionalities that can be used for a variety of modifications. One application of interest is chitosan‐based films for protective purposes, such as the packaging of food or flexible electronics . Chitosan‐based films are known to have excellent gas barrier properties at low humidity .…”

Flourishing Self‐Healing Surface Materials: Recent Progresses and Challenges

“…Furthermore, when the polymer coating surface was subjected to scratches and cuts, it healed these damages upon exposure into water (Figure 16c), which was mainly ascribed to the high molecular chain mobility and hydrogen bonding effect at PEI and HA–PAA interface. Another fascinating example of utilizing acrylamide‐modified chitosan (AMCS) and alginate aldehyde (ADA) to fabricate self‐healing, transparent, and fog‐resistant polysaccharide film using layer‐by‐layer (LBL) assembly has been reported . The contact angle of ADA/AMCS coating film was 21± 1°, after undergoing several cycles of abrasion, and the contact of angle gradually increased to 52 ± 2°, which implied the abrasion damaged the surface wettability of coating and antifogging property.…”

“…d) Water contact angle of double‐coated glass after different abrasions. Reproduced with permission . Copyright 2018, American Chemical Society.…”

Optically Active Microspheres Containing Schiff Base: Preparation and Enantio-Differentiating Release toward Drug Citronellal

“…The applications of Schiff bases have received ever-increasing attention because the characteristic chemical bond [−(CN)−] has excellent ion coordinative capability , and pH-responsive ability . Schiff bases and their derivatives have been widely used for developing catalyst intermediates, , biological sterilizations, , fluorescent reagents, , self-assembled polymers, , and polymer stabilizers . More recently, it was reported that Schiff bases can be used as electrodes for batteries and used to prepare metal–organic frameworks (MOFs) , and covalent organic frameworks (COFs) .…”

“…SCB(−) ] as an example, the release process was carried out in the mixed solution (volume ratio, water/ethanol = 1/9) because the citronellal is only slightly soluble in water. The release systems were recorded as solution (pH 1,3,5,7,11). By UV−vis spectra analysis, the results are shown in Figure4.…”