Enzymatic approaches to renewable monomers and polymers from nature

从自然界中提取可再生单体和聚合物的酶法

• 批准号: 2689541
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2689541
• 关键词: Enzymatic; approaches; renewable; monomers; polymers

Tackling the plastics problem is of huge importance to the UK. New routes to new naturally sourced and degradable polymers will be one of the key approaches that will benefit our society. At Nottingham we have recently begun to explore the development of new monomers and polymers directly from Nature. In this project we bring together two sets of Nottingham expertise in biocatalysis and supercritical fluids to make a step change in the clean synthesis of valuable new materials.Vernolic acid is a natural material from the seeds of Vernonia galamensis (ironweed), a plant widely available and native to eastern Africa that is also now being grown for potential commercial opportunities in both Canada and the USA. Vernolic acid makes up 80% of the fatty acids in the seed oil and is remarkable in that it contains very useful epoxide and olefinic functionalities. Our project is targeted at developing a range of novel polymers, surfactants and detergents from vernolic acid; with applications across packaging, personal care, cosmetics and even light-weight composites. These will be of particular interest to companies like Croda because of the ability to use a naturally available, renewable material and to lower the carbon footprint of their products. The unique functionalities retained in the fatty acid chain provide tremendous flexibility for developing new materials and applications. Moreover, this approach could also be the basis for a new business / supply chain that could benefit countries in sub-Saharan Africa and could tap into the current Global Challenges.Initial work at Nottingham has proved promising and new monomers (the unsaturated diacid above is one of several that we have now trialled) and polymers from these monomers have been developed.Monomers: Supercritical fluid extraction has proven to be a remarkably efficient and gentle methodology for extraction of the triglyceride oil from the seeds at low temperature whilst retaining the important reactive functionalities. We have then used conventional chemistries to hydrolyse and release the vernolic acid and then further conventional chemistries to convert into a wide range of new monomers (diols, diacids, diamines etc.). However, both of these processes have required routes that are not environmentally acceptable and are inefficient and wasteful. Now, we will exploit new Nottingham expertise in biocatalysis to overcome these hurdles. A screening program will be set up to carefully assess a wide range of esterases in order to find the most efficient route to releasing vernolic acid by hydrolysis from the triglyceride in an efficient and clean way. Additionally, conversion of the vernolic acid to useful functionalised monomers requires either functionalization of the olefin or opening of the epoxide and this could be much better achieved selectively via an enzymatic approach using hydratases and/or epoxide hydrolases.Polymers: Polycondensation polymerisation is typically carried out in the melt and requires high temperatures to overcome viscosity issues and to drive off water. Enzymes cannot operate under such conditions and only metal catalysts have been used, also under these conditions the useful olefin or epoxy functionalities are lost. We have shown that scCO2 can dramatically lower reaction viscosity by plasticising the monomer and growing polymer and hence allows reactions at near ambient temperature. The scCO2 also assists in removing the water by-product. This lower temperature processing provides a unique opportunity to introduce enzymes to allow controlled polymerisation and to develop desirable functionalised linear materials. Working together, we will now screen a wide range of lipases, hydratases and epoxide hydrolases to catalyse polymerisation and to create a library of new polymeric systems.

解决塑料问题对英国至关重要。新的天然来源和可降解聚合物的新途径将是造福我们社会的关键方法之一。在诺丁汉，我们最近开始探索直接从自然界开发新的单体和聚合物。在这个项目中，我们汇集了诺丁汉在生物催化和超临界流体方面的两套专业知识，在有价值的新材料的清洁合成方面进行了一步改变。斑鸠菊酸是一种来自斑鸠菊（铁草）种子的天然材料，斑鸠菊是一种广泛存在的原产于东非的植物，现在也在加拿大和美国种植，以获得潜在的商业机会。斑鸠菊酸占种子油中脂肪酸的80%，并且值得注意的是，它含有非常有用的环氧化物和烯属官能团。我们的项目旨在开发一系列新型聚合物、表面活性剂和洗涤剂;应用于包装、个人护理、化妆品甚至轻质复合材料。这些将是像禾大这样的公司特别感兴趣的，因为它们能够使用天然可再生材料，并降低其产品的碳足迹。脂肪酸链中保留的独特功能为开发新材料和应用提供了巨大的灵活性。此外，这种方法也可以成为新的商业/供应链的基础，使撒哈拉以南非洲国家受益，并可以利用当前的全球挑战。（上面的不饱和二酸是我们现在已经试验的几种之一）并且已经开发了来自这些单体的聚合物。超临界流体萃取已被证明是一种非常有效和温和的方法，用于在低温下从种子中提取甘油三酯油，同时保留重要的反应性官能团。然后，我们使用常规化学方法水解并释放佛醇酸，然后进一步使用常规化学方法转化为广泛的新单体（二醇、二酸、二胺等）。然而，这两种方法都需要环境不可接受的路线，并且效率低且浪费。现在，我们将利用新的诺丁汉生物催化专业知识来克服这些障碍。将建立筛选程序以仔细评估各种酯酶，以便找到以有效和清洁的方式通过从甘油三酯水解释放斑鸠菊酸的最有效途径。此外，将斑鸠酸转化为有用的官能化单体需要烯烃的官能化或环氧化物的打开，这可以通过使用水合酶和/或环氧化物水解酶的酶法选择性地更好地实现。聚合物：缩聚聚合通常在熔体中进行，需要高温来克服粘度问题并驱除水分。酶不能在这样的条件下操作，并且仅使用金属催化剂，而且在这些条件下，有用的烯烃或环氧官能团损失。我们已经表明，scCO 2可以通过塑化单体和生长聚合物来显著降低反应粘度，因此允许在接近环境温度下进行反应。scCO 2还有助于去除水副产物。这种较低温度的加工提供了引入酶以允许受控聚合和开发所需的官能化线性材料的独特机会。通过合作，我们现在将筛选广泛的脂肪酶，水合酶和环氧化物水解酶来催化聚合，并创建新的聚合物系统库。