English
foreword
Against the backdrop of the continuous promotion of the "dual carbon" strategy and the widespread implementation of the "bamboo for plastic" initiative, bamboo, as a rapidly renewable and sustainable natural resource, is becoming a hot topic in materials science research. The team of researcher Yu Wenji from the Wood Industry Research Institute of the Chinese Academy of Forestry has achieved the deconstruction and reorganization of bamboo through innovative multi-scale interface engineering technology, transforming bamboo into high-strength, deformable, and biodegradable bamboo cellulose based structural materials. Its comprehensive performance surpasses traditional petroleum based plastics.
01. Innovative preparation process: Multi scale bamboo fiber self-assembly achieves adhesive free bonding
Breaking through the limitations of traditional bamboo processing relying on synthetic resins, the research team has established a new multi-scale interface engineering strategy: firstly, bamboo is decomposed into fiber bundles, and then subjected to quaternization modification and TEMPO oxidation treatment to obtain positively charged long fibers (Q-Fiber) and negatively charged carboxylated cellulose nanofibers (CCNF), respectively. Utilizing the principle of electrostatic attraction to achieve fiber self-assembly, and constructing an ion crosslinked network by introducing calcium ions (Ca ² ?), combined with hot pressing technology, a dual stable structure with hydrogen bonding network and ion crosslinking is formed. This process achieves precise control of material size, constructs a three-dimensional network structure without the need for external adhesives, and transforms bamboo into a sustainable cellulose based structural material that is deformable, highly impact resistant, hard, thermally stable, biodegradable, and has excellent mechanical properties.
02. Material performance breakthrough: 1% CCNF-M exhibits excellent characteristics
Experimental data shows that the bamboo cellulose based material (1% CCNF-M) prepared by adding 1% CCNF has a dense structure, neat fiber arrangement, high proportion of crystalline zones, and significant performance advantages. The tensile strength reaches 333.4 MPa, the bending strength is 353.3 MPa, and the bending modulus is 26.8 GPa; After hydrophobic treatment, it can be used under conditions of 100% humidity or water immersion, with only a slight decrease in mechanical properties and good environmental stability; When loaded, it exhibits energy dissipation modes such as fiber pull-out and crack branching, and has a good toughening effect.
03. Performance advantage analysis: comprehensively surpassing petroleum based plastics
Compared with the average performance of petroleum based plastics, the impact strength of 1% CCNF-M has increased by 2.8 times, the hardness has increased by 1.2 times, and the specific strength has been enhanced by 4 times, truly achieving high strength while being lightweight. In addition, thanks to the excellent thermal properties of cellulose, the thermal expansion coefficient of multi-scale materials is extremely low (<1.19 × 10 ??? K ?¹), and the thermal stability is excellent. At the same time, the good flexibility and orderly arrangement of fibers in the material give it excellent processability, making it easy to shape. In terms of environmental protection, 1% CCNF-M also performs excellently. After being buried for 360 days, the material degrades significantly, making it far more environmentally friendly than plastic.
04. Environmental benefits and application prospects
The results of the life cycle assessment indicate that among all investigated environmental impact categories, multi-scale bamboo based cellulose materials outperform traditional petroleum based plastics and are strong candidates for reducing carbon emissions and carbon footprint. In addition, by changing the way fibers are laid, the properties of the material can be transformed from anisotropic to isotropic, providing greater flexibility and possibilities for the application of cellulose based materials instead of plastics.
conclusion
This study utilized multi-scale interface engineering to deconstruct and reassemble bamboo, achieving a magnificent transformation of bamboo through physical and chemical means such as dense hydrogen bonding networks, surface charge treatment, and ion crosslinking. The multi-scale bamboo cellulose material prepared has significantly better comprehensive properties than current commercial plastics (including some engineering plastics), and surpasses traditional biomass based structural materials in mechanical properties and other indicators. The research has made a breakthrough in solving technical bottlenecks such as large mechanical performance variability, weak interface bonding, and dimensional stability in bamboo applications, providing complete theoretical support and technical solutions for bamboo resources to replace non degradable plastics. With the optimization of processes and the promotion of industrialization, these customizable and fully degradable cellulose based materials are expected to form large-scale applications in precision instrument manufacturing, environmentally friendly packaging, green buildings and other fields, opening up new technological paths for achieving the "dual carbon" goal.
