Inspired by the hierarchically ordered “brick and mortar” (BM) architecture of natural nacre, in this study a rational assembly of boron nitride (BN) nanosheets was introduced into a mixture of trimethylolpropane triglycidyl ether (TTE) and soy protein isolate (SPI), and a strong and multifunctional SPI-based nanocomposite film with multinetwork structure was synthesized. At a low BN loading (<0.5%), the resulting multifunctional film was flexible, antiultraviolet, and nearly transparent and also displayed good thermal diffusion ability and exhibited an excellent combination of high tensile strength (36.4 MPa) and thermal conductivity (TC, 2.40 W·m–1·K–1), surpassing the performances of various types of petroleum-based plastics (displayed a tensile strength ranging from 1.9 to 21 MPa and TC ranging from 0.55–2.13 W·m–1·K–1), including nine different types of materials currently utilized for mobile phone shells, suggesting its vast potential in practical applications.

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Soy protein isolate (SPI) is envisioned as a promising alternative to fabricate “green” flexible electronics, showing great potential in the field of flexible wearable electronics. However, it is challenging to simultaneously achieve conductive film-based human motion-monitoring strain sensors with reliable fatigue resistance, robust mechanical property, environmental degradability, and sensing capability of human motions. Herein, we prepared a series of SPI-based nanocomposite films by embedding a surface-hydroxylated high-dielectric constant inorganic filler, BaTiO3, (HBT) as interspersed nanoparticles into a biodegradable SPI substrate. In particular, the fabricated film comprising 0.5 wt % HBT and glycerin (GL), namely, SPI–HBT0.5–GL0.5, presents multifunctional properties, including a combination of excellent toughness, tensile strength, conductivity, translucence, recyclability, and excellent thermal stability. Meanwhile, this multifunctional film could be simply degraded in phosphate buffered saline solution and does not cause any pollution to the environment. Attractively, wearable sensors prepared with this particular material (SPI–HBT0.5–GL0.5) displayed excellent biocompatibility, prevented the occurrence of an immune response, and could accurately monitor various types of human joint motions and successfully remain operable after 10,000 cycles. These properties make the developed SPI-based film a great candidate in formulating biobased and multifunctional wearable electronics.

A microwave (MW) treatment of plantation eucalyptus (Eucalyptus urophylla) wood was investigated by applying MW treatments with varying conditions, such as radiation power, irradiation time, and initial moisture content of the wood. The wood permeability and drying properties were investigated. Results show that the permeability (both along the transverse and longitudinal directions) increased with the radiation power and the irradiation time. The permeability was considerably enhanced by the MW pretreatments, which effectively decreased the moisture content within the wood. A MW pretreatment can greatly accelerate the drying rate and shorten the wood drying time. Under atmospheric pressure the stain uptake along the transverse and longitudinal directions, with respect to the wood fibers, increased to 58% and 135%, respectively, compared to reference samples. Meanwhile, the drying rate increased to 171% and the drying time was cut by 65%. The MW pretreatment was found to generate a high-pressure internal steam that resulted in the rupture of wood cell pore membranes and ray cells. Therefore, a remarkable permeability increase and drying time reduction was achieved, which created favorable conditions for the fabrication of high value-added functional wood-based composites materials.

Soy protein isolate (SPI) film is considered a promising biomaterial for the replacement of petroleum‐based food packaging plastics. However, current SPI films are still replying on petroleum‐based crosslink agents. In this paper, a green and effective approach is developed to prepare a full biomass‐based sustainable film with high strength and toughness by incorporating feather keratin (FK, extracted from the waste chicken feathers) into the SPI via the reaction of disulfide bonds. The broken disulfide bonds in FK are recombined with the sulfhydryl group on the SPI molecular chains to form a cross‐linked network. Compared to the SPI film, the tensile strength of the SPI/FK composite film is increased by 242% to 8.2 MPa and the toughness is increased by 152% to 9.18 MJ m−3. The thermal stability and the water resistance of the SPI/FK composite films are also improved. The replacement rate of FK‐modified SPI is up to 40%. Since the film is 100% made from bio‐based materials, it would be biodegradable. This research provides a green and economic approach to improve the performance of protein‐based food packaging films by introducing FK as an enhancer and constructing disulfide bonds cross‐linked network structure in the protein system.