Lignin as a Wood‐Inspired Binder Enabled Strong, Water Stable, and Biodegradable Paper for Plastic Replacement

Abstract

Plastic waste has been increasingly transferred from land into the ocean and has accumulated within the food chain, causing a great threat to the environment and human health, indicating that fabricating an eco‐friendly and biodegradable replacement is urgent. Paper made of cellulose is attractive in terms of its favorable biodegradability, resource abundance, large manufacturing scale, and low material cost, but is usually hindered by its inferior stability against water and poor mechanical strength for plastic replacement. Here, inspired by the reinforcement principle of cellulose and lignin in natural wood, a strong and hydrostable cellulosic material is developed by integrating lignin into the cellulose. Lignin as a reinforced matrix is incorporated to the cellulose fiber scaffold by successive infiltration and mechanical hot‐pressing treatments. The resulting lignin‐cellulose composite exhibits an outstanding isotropic tensile strength of 200 MPa, which is significantly higher than that of conventional cellulose paper (40 MPa) and some commercial petroleum‐based plastics. Additionally, the composite demonstrates a superior wet strength of 50 MPa. Adding lignin also improves the thermostability and UV‐blocking performance of cellulose paper. The demonstrated lignin‐cellulose composite is biodegradable and eco‐friendly with both components from natural wood, which represents a promising alternative that can potentially replace the nonbiodegradable plastics.

Toward a Consolidated Lignin Biorefinery: Preserving the Lignin Structure through Additive‐Free Protection Strategies

“…The cellulose‐rich fiber fraction could also be used in a similar way to the hemicellulose fractions described above. Alternatively, fiber‐based composites are becoming attractive and the presence of lignin in the fibers has been shown to enhance the thermomechanical properties of such materials . Based on the lignin content of the fiber residue in this work, such potential applications could be investigated.…”

Advanced Materials and Systems for Biodegradable, Transient Electronics

“…Regulation of the lifetime of electronic system proposed the application capability that can eliminate the risk of reoperations and subsequent pains to replace or retrieve implanted devices after clinically useful timeframes. [36,[86][87][88][89][90][91] Figure 6a describes real-time, continuous monitoring of intracranial pressure and temperature essential to medicinal or surgical management for traumatic brain injury. A proposed system introduced bioresorbable silicon electronics, with other sensors connected to a miniaturized wireless communication tool, suggesting administration or application of remedies in clinical medicine.…”

“…[ 35 ] Figure 2b provides an example of functional cellulose papers that compensated for such shortcomings in a way that integration of lignin into the cellulose offered enhanced water stability and mechanical robustness, as well as thermal endurance and ultraviolet (UV)‐resistant ability. [ 36 ] This complex material maintained its shape and stiffness without noticeable morphological changes, while cellulose papers fell apart into microfibers. As a principal component of cell walls in fungi and the exoskeletons of arthropods, chitin was engineered to enable to yield a thin, large‐scale (5 in) sheet of chitin nanofibers (ChNFs), providing favorable optical (transmittance of 92%) and mechanical (elastic modulus 4.3 GPa) properties potentially applicable for flexible, green optical elements (Figure 2c).…”

“…Reproduced with permission. [ 36 ] Copyright 2020, Wiley‐VCH. c) Photographs of squid pen containing a biodegradable β‐chitin (left) and chitin nanofibers (ChNFs)‐based transparent film for flexible green electronics (right).…”

Screening of Nanocellulose from Different Biomass Resources and Its Integration for Hydrophobic Transparent Nanopaper

“…However, their non-renewability and hard degradability have contributed to environmental pollution and the unsustainable utilization of resources [2]. Therefore, under the background of increasing awareness of environmental protection and posing emphasis on sustainable development of social economy, to seek green, renewable, and biodegradable material as an alternative is important and urgent [3].…”