A Biodegradable, Waterproof, and Thermally Processable Cellulosic Bioplastic Enabled by Dynamic Covalent Modification

Abstract

The growing environmental concern over petrochemical-based plastics continuously promotes the exploration of green and sustainable substitute materials. Compared with petrochemical products, cellulose has overwhelming superiority in terms of availability, cost, and biodegradability; however, cellulose's dense hydrogen-bonding network and highly ordered crystalline structure make it hard to be thermoformed. A strategy to realize the partial disassociation of hydrogen bonds in cellulose and the reassembly of cellulose chains via constructing a dynamic covalent network, thereby endowing cellulose with thermal processability as indicated by the observation of a moderate glass transition temperature (T g = 240 °C), is proposed. Moreover, the cellulosic bioplastic delivers a high tensile strength of 67 MPa, as well as excellent moisture and solvent resistance, good recyclability, and biodegradability in nature. With these advantageous features, the developed cellulosic bioplastic represents a promising alternative to traditional plastics.

Reconstruction of Cellulose Intermolecular Interactions from Hydrogen Bonds to Dynamic Covalent Networks Enables a Thermo-processable Cellulosic Plastic with Tunable Strength and Toughness

“…Besides chemical recycling, cellulose plastics also can be mechanically recycled due to the presence of dynamic imine linkages enabling excellent cellulosic plastic reprocessability. − As shown in Figure S31a,b, the discarded cellulosic plastic DS=0.4 debris can be easily recycled via heat-pressing formation for the preparation of a new batch of cellulosic plastic DS=0.4 films. Figure S31c shows that the recovery of the tensile strength for cellulosic plastic DS=0.4 is 76%.…”

Long-Chain Polyamine-Glyoxal Wood Adhesive: Formaldehyde-Free, Green Synthesis, and Ultra-Performances

“…To underpin the FT-IR and Raman results, the XPS examination was also carried out, and the fitted spectra for C 1s and N 1s are given in Figure 5c,d. By referring to the literature, 27 the characteristic peaks corresponding to binding energy at 287.88 eV of C 1s and 400.88 eV of N 1s can be indications for C�N bond formation. Additionally, an amorphous structure was verified by XRD (Figure 5e), signifying the formation of crosslinked structure.…”

Supramolecular covalent cellulose-based bioplastics with high transparency, hydrophobicity, ionic conductivity, mechanical robustness, and recyclability

“…10 Due to their preparation from abundant cellulose stocks, wide availability, biodegradability, and recyclability, cellulose-based bioplastics (CBPs) have attracted extensive interest from researchers. 11–18 CBPs are usually produced via , for example, direct blending/crossliking, 11,12,19,20 chemical modification of cellulose, 18,21 low-temperature alkali/urea system solubilization, 22,23 or other solvent treatments. 16,17,24 Although CBPs exhibit good overall performance, they are usually associated with hydrophilicity, a dark color or opaqueness, performance degradation upon recycling, and overall monofunctionality.…”