SusChEM: Structure and Property Study of Nascent Cellulose Nanocrystals and Their Use in Water Purification

SusChEM：新生纤维素纳米晶体的结构和性能研究及其在水净化中的应用

• 批准号: 1409507
• 负责人: Benjamin Hsiao
• 金额: $ 52万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1409507&HistoricalAwards=false
• 关键词: SusChEM; Structure; Property; Study; Nascent

NON-TECHNICAL SUMMARY: Cellulose is an abundant renewable polymer from plants and can be processed into fibers of different thicknesses all the way down to the nanoscale. However, the morphology and property relationships of the primary structural components -- cellulose crystals and microfibrils -- in the natural cellulose are still not clear. In order to more effectively incorporate sustainable nanoscaled cellulose into composite materials, including water filtration membranes, it is necessary to improve our fundamental understanding of the structure, morphology and properties of these polymers as functions of fiber source and processing methods. This research includes both an experimental and a theoretical component and extends from fundamental science to water-filtration applications. It will also have a broad impact in training of students in scientific research relevant to sustainable materials. A range of educational activities will be developed to engage undergraduate and high school students in thinking about access to clean water as an issue of global sustainability while learning about the fundamental concepts on water purification. This project has the potential to lead to the development of new environmentally and economically sustainable materials for water filtration that could positively impact the lives of many people around the globe. TECHNICAL SUMMARY: The goal of this project is to develop a fundamental understanding of the structure, morphology and properties of cellulose microfibrils (i.e., nascent crystals), their relationships with fiber source and isolation method, and the applications of these naturally occurring nanoscale materials for water purification. This research takes advantage of the recent findings that the chemical treatment using TEMPO-mediated oxidation followed by mechanical disintegration can produce negatively charged cellulose microfibrils. The large surface density of charged carboxylate groups in oxidized microfibrils not only improves the dispersion capability in water, allowing detailed structural analysis, but also provides opportunities for chemical grafting of other radicals. In this research, structural information on cellulose microfibrils will be determined by combined synchrotron small-angle X-ray scattering (SAXS), high-resolution transmission electron microscopy (TEM) and molecular simulation techniques. In addition, surface-modified cellulose microfibrils (with both positive and negative charge capability) will be explored as superabsorbent materials to remove contaminants (e.g. viruses and toxic metal ions) in water, and their performance will be correlated with structure and functionality.

非技术摘要：纤维素是植物中丰富的可再生聚合物，可以从纳米级一直到具有不同厚度的纤维进行处理。 然而，天然纤维素中主要结构成分（纤维素晶体和微纤维）的形态和性质关系仍然不清楚。为了更有效地将可持续的纳米核纤维素纳入复合材料，包括水过滤膜，有必要提高我们对这些聚合物的结构，形态和特性的基本理解，作为纤维源和加工方法的功能。这项研究包括实验和理论成分，并从基本科学延伸到滤水应用。 这也将对培训与可持续材料相关的科学研究学生的培训产生广泛的影响。将开发一系列教育活动，以吸引本科生和高中生，以考虑获得清洁水作为全球可持续性问题，同时了解有关水净化的基本概念。该项目有可能导致开发新的环境和经济可持续性材料，以积极影响全球许多人的生活。 技术摘要：该项目的目的是对纤维素微纤维的结构，形态和特性（即，新生晶体），它们与纤维源和隔离方法的关系以及这些自然发生的纳米级材料的应用，对结构，形态和特性进行基本了解水净化。 这项研究利用了最近的发现，即使用节气介导的氧化，然后进行机械瓦解的化学处理可以产生带负电荷的纤维素微纤维。氧化微纤维中带电的羧酸盐基团的表面密度不仅可以提高水的分散能力，从而允许详细的结构分析，而且还为其他自由基化学移植提供了机会。在这项研究中，有关纤维素微纤维的结构信息将通过合并的同步子小角X射线散射（SAXS），高分辨率透射透射电子显微镜（TEM）和分子模拟技术来确定。此外，将探索表面修饰的纤维素微纤维（具有正电荷能力和负电荷能力）作为超吸收材料，以去除水中的污染物（例如病毒和有毒金属离子），其性能将与结构和功能相关。