Synthesis of completely biobased lignin-formaldehyde resins with catalytically activated lignin products

用催化活化木质素产品合成完全生物基木质素甲醛树脂

• 批准号: 1804557
• 负责人: Charles Frazier
• 金额: $ 30万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804557&HistoricalAwards=false
• 关键词: Synthesis; completely; biobased; lignin; formaldehyde

The proposed project aims to develop a chemical process to convert a material found in plants called lignin to a more valuable material called lignin-formaldehyde (LF) resin. Completely bio-based LF resins can replace of phenol-formaldehyde resins, which a common material used in myriad of industrial products, such as countertops, coatings, adhesives, billiard balls, etc. Lignin contains phenolic units that make it a potential renewable substitute for phenol in the synthesis of the resin. However, lignin itself has limited reactivity towards formaldehyde. To overcome this problem, a new catalytic process is proposed to enhance the reactivity of lignin products. The proposed research may lead to the development of technologies that add value to lignin from biomass waste streams and can have positive impact on the environment and on rural economies. Catalytic depolymerization and demethoxylation of lignin into small fragments can generate free phenolic hydroxyls and free ortho positions for formaldehyde addition and crosslinking. This pathway can overcome the limited reactivity of lignin towards formaldehyde. Preliminary results have shown that inexpensive catalysts, such as metal sulfides, could catalyze depolymerization and demethoxylation of lignin. LF resins can be subsequently synthesized from phenolic compounds with two ortho positions and be cured with the addition of multiple-ortho-position compounds. Catalysts will be screened through model compound studies on dimers featuring various kinds of interunit linkages. The optimal ratios of monomer/dimers (and/or oligomers) for LF resin synthesis will by studied by synthesizing LF resins from model compounds. The research results will be incorporated in courses at Virginia Polytechnic Institute and State University aimed at educating students about biomass-derived fuels and value-added products. Outreach activities to high school students are planned with emphasis on attracting members of underrepresented groups into pursuing careers in science and engineering.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.

拟议中的项目旨在开发一种化学过程，将植物中的木质素转化为更有价值的木质素-甲醛（LF）树脂。全生物基LF树脂可以取代酚醛树脂，酚醛树脂是无数工业产品的常用材料，如台面、涂料、粘合剂、台球等。木质素含有酚类单位，使其成为树脂合成中苯酚的潜在可再生替代品。然而，木质素本身对甲醛的反应性有限。为了克服这一问题，提出了一种新的催化工艺来提高木质素产物的反应性。拟议的研究可能会导致技术的发展，增加生物质废物流中木质素的价值，并可能对环境和农村经济产生积极影响。木质素催化解聚和脱甲氧基化成小片段，可生成游离酚羟基和游离邻位，用于甲醛加成和交联。该途径可以克服木质素对甲醛的有限反应性。初步结果表明，金属硫化物等廉价催化剂可以催化木质素的解聚和脱甲氧基化。LF树脂随后可由具有两个邻位的酚类化合物合成，并可通过添加多个邻位化合物固化。催化剂将通过具有各种单元间键的二聚体的模型化合物研究来筛选。通过模型化合物合成低聚体树脂，研究低聚体/二聚体（和/或低聚体）的最佳比例。研究结果将被纳入弗吉尼亚理工学院和州立大学的课程，旨在向学生传授生物质衍生燃料和增值产品。计划向高中生开展外展活动，重点是吸引代表性不足的群体成员从事科学和工程方面的职业。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。