Mechanics of Bioderived-Cellulose-Based Ultra-Strong and Ultra-Tough Materials

该研究计划将侧重于探索设计策略，以实现基于生物衍生纤维素的超强和超韧材料。纤维素是地球上最丰富的生物聚合物，长期以来一直用于生产纸制品。纤维素具有优异的力学性能，是高性能功能和结构材料的重要组成部分。虽然植物是纤维素的常见来源，但需要额外的物理和化学处理来从植物中分离和纯化纤维素，并且这种处理可能会潜在地降低植物纤维素的机械性能。此外，树木通常需要数年或数十年才能成熟，这对种植纤维素造成了巨大的时间成本。通过微生物发酵工艺生产的生物衍生纤维素化学纯度为100%，具有比植物纤维素更好的性能，并且可以在几天内以低成本以工业规模获得。该研究计划旨在使用实验和计算研究来研究控制生物衍生纤维素的优异机械性能的基础科学。这项研究计划的成功可能会为设计高性能工程材料带来低成本和长期寻求的解决方案。这项研究还将通过建立一个全面的教育和外展计划来补充，包括为研究生和本科生提供研究机会、为代表性不足的少数族裔高中生提供实习、在一年一度的马里兰州日进行公共外展以及通过网络进行研究传播基础设施。本研究计划的具体目标是：（a）探索一种有前途但尚未探索的策略，通过离子渗透提高生物衍生纤维素材料的机械性能，以及（B）破译生物衍生纤维素材料的优异机械性能与纤维素纤维长度/排列和含水量的基本相关性。这项研究将通过一个连贯的研究框架，结合实验和多尺度建模进行。通过揭示纤维素卓越的内在机械性能的基础科学，该项目有望推动纤维素使用的范式转变，超越其传统方式。这项研究计划产生的新知识将为开发地球上最丰富的生物聚合物纤维素内在优异机械性能的全部潜力提供丰富的机会。从这项研究中产生的基本科学认识可以丰富材料力学的学科与多个诱人的研究前沿，并很容易适应和推广到其他材料system.This奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

This research program will focus on exploring design strategies to achieve ultra-strong and ultra-tough materials based on bioderived cellulose. Cellulose is the most abundant biopolymer on Earth and has long been used to produce paper products. Cellulose has remarkable mechanical properties, making it as a promising building block for high performance functional and structural materials. While plants are the common source of cellulose, it requires extra physical and chemical processing to isolate and purify cellulose from plants, and such processing can potentially decrease the mechanical performance of plant cellulose. Moreover, trees often take years or decades to mature, posing substantial time cost to plant cellulose. Bioderived Cellulose produced through a microscopic organism enabled fermentation process is chemically 100% pure with much better properties than plant cellulose and can be obtained at industrial scale at a low cost within days. This research program aims to use both experimental and computational studies to investigate the fundamental science that governs the superb mechanical properties of bioderived cellulose. The success of this research program can potentially lead to a low-cost and long-sought solution in designing high performance engineering materials. The research will also be complemented by establishing a well-rounded educational and outreach program including research opportunities for graduate and undergraduate students, internship for underrepresented minority high school students, public outreach at the annual Maryland Day, and research dissemination via cyberinfrastructure. The specific goal of this research program is (a) to explore a promising but largely unexplored strategy to enhance the mechanical properties of bioderived cellulose materials via ion infiltration, and (b) to decipher the fundamental correlation of the superb mechanical properties of bioderived cellulose materials with cellulose fiber length/alignment and water content. The research will be conducted via a coherent research framework integrating experiments and multiscale modeling. By revealing the fundamental science of the superb intrinsic mechanical properties of cellulose, the project holds promise to drive a paradigm shift in the usage of cellulose beyond its conventional way. The new knowledge generated from this research program will shed light fertile opportunities to exploit the full potential of the intrinsic superb mechanical properties of cellulose, the most abundant biopolymer on Earth. The fundamental scientific understanding emerging from this study can enrich the disciplines of mechanics of materials with multiple tantalizing research frontiers and be readily adapted and generalized to other material systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.