Simultaneously Toughening and Strengthening Soy Protein Isolate-Based Composites via Carboxymethylated Chitosan and Halloysite Nanotube Hybridization

Abstract

Chemical cross-linking modification can significantly enhance the tensile strength (TS) of soy protein isolate (SPI)-based composites, but usually at the cost of a reduction in the elongation at break (EB). In this study, eco-friendly and high-potential hybrid SPI-based nanocomposites with improved TS were fabricated without compromising the reduction of EB. The hybrid of carboxymethylated chitosan (CMCS) and halloysite nanotubes (HNTs) as the enhancement center was added to the SPI and 1,2,3-propanetriol-diglycidyl-ether (PTGE) solution. The chemical structure, crystallinity, micromorphology, and opacity properties of the obtained SPI/PTGE/HNTs/CMCS film was analyzed by the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and UV-Vis spectroscopy. The results indicated that HNTs were uniformly dispersed in the SPI matrix without crystal structure damages. Compared to the SPI/PTGE film, the TS and EB of the SPI/PTGE/HNTs/CMCS film were increased by 57.14% and 27.34%, reaching 8.47 MPa and 132.12%, respectively. The synergy of HNTs and CMCS via electrostatic interactions also improved the water resistance of the SPI/PTGE/HNTs/CMCS film. These films may have considerable potential in the field of sustainable and environmentally friendly packaging.

A Natural Antibacterial-Antioxidant Film from Soy Protein Isolate Incorporated with Cortex Phellodendron Extract

“…The XRD patterns of the CPE-free film and SPI/CPE films are shown in Figure 2 . The peaks for the CPE-free film appeared at 2θ values of 8.9° and 19.9°, reflecting the α-helix and β-sheet structures of the SPI secondary conformation, respectively [ 20 ]. The CPE-free film showed a dominant amorphous halo and a broad peak at 2θ of around 21.8°, indicating that amorphous globulin (7S and 11S) was the important part in film [ 21 ].…”

Improvement in Functional Properties of Soy Protein Isolate-Based Film by Cellulose Nanocrystal–Graphene Artificial Nacre Nanocomposite

“…Biodegradable and sustainable biopolymers derived from natural resources, such as proteins, cellulose, lignin and polysaccharides, have aroused considerable interest in developing alternatives to petroleum-derived plastics [ 1 , 2 , 3 , 4 , 5 ]. In comparison with other natural biopolymers, soy protein isolate (SPI) derived from plant proteins has been the focus of much research owing to its advantages of low cost, biodegradability, biocompatibility, and easy availability [ 6 , 7 , 8 , 9 ]. These notable advantages make it an ideal material for various applications in packaging materials [ 10 ], filtration membranes [ 11 ], drug delivery systems [ 12 ], and tissue engineering [ 13 ].…”

Physical, mechanical and water barrier properties of yuba films incorporated with various types of additives

“…All films showed two classic peaks at around 9° and 19.3°, corresponding to the diameters of α ‐helix and β ‐sheet structure, respectively . These patterns are in accordance with the results of SPI films . After incorporating additives into yuba films, the peak at 10.4° of Con shifted to lower angles, ranging from 7.36° to 9.49° (Table ).…”

“…43 These patterns are in accordance with the results of SPI films. 44,45 After incorporating additives into yuba films, the peak at 10.4 ∘ of Con shifted to lower angles, ranging from 7.36 ∘ to 9.49 ∘ (Table 3). This phenomenon might be ascribed to an enlargement in d spacing at an angle of 2 ≈ 9 ∘ and a change of the crystal lattice resulting from the rearranged -helix structure in modified yuba films.…”