Because of its non-toxic, pollution-free, and low-cost advantages, environmentally-friendly packaging is receiving widespread attention. However, using simple technology to prepare environmentally-friendly packaging with excellent comprehensive performance is a difficult problem faced by the world. This paper reports a very simple and environmentally-friendly method. The hydroxyl groups of cellulose nanofibrils (CNFs) were modified by introducing malic acid and the silane coupling agent KH-550, and the modified CNF were added to cassava starch as a reinforcing agent to prepare film with excellent mechanical, hydrophobic, and barrier properties. In addition, due to the addition of malic acid and a silane coupling agent, the dispersibility and thermal stability of the modified CNFs became significantly better. By adjusting the order of adding the modifiers, the hydrophobicity of the CNFs and thermal stability were increased by 53.5% and 36.9% ± 2.7%, respectively. At the same time, the addition of modified CNFs increased the tensile strength, hydrophobicity, and water vapor transmission coefficient of the starch-based composite films by 1034%, 129.4%, and 35.95%, respectively. This material can be widely used in the packaging of food, cosmetics, pharmaceuticals, and medical consumables.

Composite films of polybutylene adipate terephthalate (PBAT) were prepared by adding thermoplastic starch (TPS) (TPS/PBAT) and nano-zinc oxide (nano-ZnO) (TPS/PBAT/nano-ZnO). The changes of surface morphology, thermal properties, crystal types and functional groups of starch during plasticization were analyzed by scanning electron microscopy, synchronous thermal analysis, X-ray diffraction, infrared spectrometry, mechanical property tests, and contact Angle and transmittance tests. The relationship between the addition of TPS and the tensile strength, transmittance, contact angle, water absorption, and water vapor barrier of the composite film, and the influence of nano-ZnO on the mechanical properties and contact angle of the 10% TPS/PBAT composite film. Experimental results show that, after plasticizing, the crystalline form of starch changed from A-type to V-type, the functional group changed and the lipophilicity increased; the increase of TPS content, the light transmittance and mechanical properties of the composite membrane decreased, while the water vapor transmittance and water absorption increased. The mechanical properties of the composite can be significantly improved by adding nano-ZnO at a lower concentration (optimum content is 1 wt%).

Chlorine dioxide is classified by the World Health Organization as a fourth-generation A1, widely used, safe, and effective disinfectant. It is widely used in bleaching, water treatment, oil extraction, aquaculture, plants, fruits and vegetables, meat products, preservation of aquatic products, food sterilization and sterilization industries. The technology of chlorine dioxide produced by the combination reduction method is widely used in domestic papermaking related companies. In order to promote the application of chlorine dioxide, the effects of storage conditions on the stability of chlorine dioxide solution prepared by the combination reduction method and the experimental study of decomposition kinetics were studied. Experiments have shown that high temperature, high pH and high initial concentration accelerate the decomposition of chlorine dioxide solution, and the addition of sodium dihydrogen phosphate (NaH₂PO₄) and dimethyl sulfoxide (DMSO) can inhibit the decomposition of chlorine dioxide. The kinetic experiments showed that the decomposition rate of chlorine dioxide was secondary to ClO₂ and was −0.406 for [ H + ] [{\mathrm{H}^{+}}] . The apparent activation energy of chlorine dioxide solution decomposition reaction was 26.7 kJ·mol⁻¹, and the decomposition rate equation of chlorine dioxide was established.

Biomass materials have become a research focus for humankind, due to the decreasing availability of fossil fuels and the increasing release of greenhouse gas. In this work, we prepared biodegradable composites with waste cassava residues and polybutylene succinate (PBS) by modifying cassava residues using 4,4’-methylene diisocyanate phenyl ester (MDI) and tested their properties. The effects of MDI modification on the structure, mechanical properties, water absorption, microstructure, and thermal stability of the composites were studied via Fourier transform infrared spectroscopy, contact angle measurement, mechanical property testing, water absorption analysis, scanning electron microscopy, and thermogravimetric analysis, respectively. The results showed that the tensile strength and flexural strength of the material increased by 72% and 20.89%, respectively, when the MDI-modified cassava residue content was 30%. When 10% MDI-modified cassava residues were added, the tensile strength increased by 19.46% from 16.96 MPa to 20.26 MPa, while the bending strength did not change significantly. The water contact angle of the MDI-treated cassava residues exceeded 100°, indicating excellent hydrophobicity. Thus, MDI modification can significantly improve the mechanical properties and thermal stability of the biocomposite. The composites were immersed in distilled water for 96 h. The water absorption of the cassava residues/PBS composite was 2.19%, while that of the MDI-modified cassava residues/PBS composite was 1.6%; hence, the water absorption of the MDI-modified cassava residues/PBS composite was reduced to 26.94%. This technology has wide application potential in packaging, construction, and allied fields.

Most existing polymer plastics are nonreusable and also exhibit poor biocompatibility and a poor mechanical strength–tensile strain balance. Herein, using deep eutectic polymers, we prepare reusable hydrophilic supramolecular dry gel plastics with balanced stress–strain characteristics through the hydrogen bonding of poly(vinyl alcohol) (PVA) with betaine (Bta). As PVA exhibits crystalline stiffness and abundant hydrogen-bonding sites, it is employed as a network backbone in the proposed deep eutectic supramolecular polymers. In the prepared PVA/Bta dry gel plastics, PVA and Bta are dynamically and physically crosslinked through high-density hydrogen bonding, resulting in a yield strength of ~109 MPa and toughness of up to ~210.92 MJ m⁻³. In addition, these plastics can be recycled at least five times in an aqueous environment while maintaining a mechanical strength of 100 MPa. Furthermore, the proposed polymers exhibit high transparency (92%) in the visible spectrum. We expect these polymers to be used in synthesizing biodegradable dry gel plastics, as well as to lead to the development of recyclable deep eutectic PVA/Bta polymers with remarkable strength.