Bio-fabrication of sustainable functional bacterial cellulose aerogel for building insulation

气候变化无疑是我们这一代人面临的最大挑战。世界绿色建筑理事会正在推动建筑业和房地产业向净零碳建筑环境过渡。在英国，建筑物的运营约占排放的30%，主要来自供暖、制冷和电力使用。建筑物的供暖和供冷占全球能源消耗的10%以上。人们越来越重视能源效率和减少我们家庭和工作场所的碳排放。英国政府热衷于看到建筑能效的提高，并提供各种举措和方案来为家庭住宅隔热，以改善建筑能源。然而，聚苯乙烯和聚氨酯等工业合成保温材料在建筑保温行业占据主导地位。它们是以石油为基础的聚合聚苯乙烯，这些材料的制造是一个能源密集型过程。此外，所有的合成绝缘泡沫都不是透气的，这会导致墙壁受潮和腐烂。其中一些会在火灾中释放有毒的氰化氢和异氰酸酯。尽管人们对使用生物基隔热产品的兴趣在稳步增加，但高效隔热的可再生材料或生物基材料，如木屑、羊毛料和再生纸，通常不如以化石燃料为基础的材料，如发泡聚苯乙烯和聚氨基甲酸酯泡沫。为了满足对可持续和净零碳建筑行业的需求，迫切需要创新的绝缘材料，以促进低能源消耗和对环境的最小影响。NIA的这项提案是为了在如何利用可再生和可降解的资源取代石油衍生品生产技术，减少对环境的破坏，实现可持续发展方面取得突破。这项提议是利用生物技术改造建筑绝缘材料制造的第一步，以开发新型纤维素气凝胶，以减少化石能源需求，并为净零碳建筑做出贡献。最根本的挑战是开发新的低成本、低能耗的常温干燥方法，以制备具有阻燃、绝缘和抗菌性能的功能性细菌纤维素气凝胶，这将在建筑材料领域具有关键应用。研究低成本、低能耗的碳酸氢钠干燥方法。将研究工艺的影响，特别是与去除溶剂以产生低密度泡沫和气凝胶相关的挑战对热传递性能的影响。通过在建筑绝缘应用中加入功能性壳聚糖来提供所需的光催化自清洁、抗菌和阻燃性能，将采用原位自适应改性方法来解决使用细菌纤维素气凝胶的挑战。该提案的跨学科性质将为生物工程、建筑物理和工业合作伙伴建立一个真正的网络，让他们在自己的学科领域之外合作并进行研究，以创造用于节能建筑的新一代可再生和可降解的生物纤维素气凝胶。这项研究目前处于概念验证阶段，具有很高的影响潜力，未来将有广泛的应用。这种方法将使绝缘材料的制造能够利用废物，几乎没有能源投入，并且以碳封存和无污染的方式进行。它在生产可再生隔热材料方面具有巨大的潜力，其热传输性能明显好于目前商业上占主导地位的材料，如发泡聚苯乙烯、聚氨酯泡沫塑料和玻璃棉。

Climate change is undoubtedly the greatest challenge of our generation. The World Green Building Council is catalysing the construction and property industry to lead the transition to a net zero carbon-built environment. In the UK, the operation of buildings accounts for around 30 percent of emissions, mainly from heating, cooling and electricity use. Heating and cooling in buildings accounts for over 10% of global energy consumption. There is an increasing emphasis on energy efficiency and cutting carbon emissions from our homes and workplaces. The UK Government is keen to see energy efficiency in buildings improved and various initiatives and schemes offered for insulating domestic homes for building energy improvements. However, industrial synthetic insulation materials, such as polystyrene and polyurethane, dominate the building insulation industry. They are oil based polymerised polystyrene and the manufacturing of those materials is an energy intensive process. Moreover, all the synthetic insulation foams are not vapour permeable, which can cause dampness as well as decay in the wall. Some of them will release toxic hydrogen cyanide and isocyanates during a fire. Although interest in the use of bio-based insulation products is steadily increasing, the efficient thermal insulation renewable or biobased materials such as wood chips and sheep wools and recycled paper are generally inferior to that of fossil fuel-based materials such as expanded polystyrene and polyurethane foams. To meet the demand for a sustainable and net zero carbon building industry, there is a pressing need for innovative insulation materials that would facilitate low energy consumption and a minimal impact on the environment. This NIA proposal is to make breakthroughs in how to use renewable and degradable resources to replace petroleum derivatives production technology, reduce environmental damage, and achieve sustainable development. This proposal is a first step to transform the manufacture of building insulating materials using biotechnology to develop novel cellulose-based aerogel to reduce fossil energy demand and contribute to net zero carbon buildings. The fundamental challenge is to develop novel low cost and low energy intensive ambient drying methods to produce functional bacterial cellulose aerogels with flame retardant, insulation, and anti-bacterial properties, which will have key applications in the field of construction materials. The low cost and low energy intensive drying method using sodium bicarbonate will be studied. The effect of the processing and in particular, the challenges related to the removal of the solvent to generate low-density foams and aerogels on heat transfer properties will be investigated. An In-situ adaptive modification approach will be applied to address the challenges for using bacterial cellulose aerogel by incorporating functional chitosan in building insulation applications to provide the desired photo-catalytic self-cleaning, antibacterial and flame retardant properties. The interdisciplinary nature of proposal will build a real network for Bioengineering, building physics and Industry partners to work together and conduct research outside of their own discipline area to create a new generation of renewable and degradable bio-cellulose aerogel for energy efficient building. This research is currently at proof-of-concept stage and has high potential for impact with a wide array of applications in the future. This approach will enable the manufacture of insulation materials utilising waste, with little energy input and in ways which are carbon sequestering and non-polluting. It has enormous potential to produce renewable thermally insulating materials with significantly better heat transport properties than the currently commercially dominating materials such as expanded polystyrene, polyurethane foams, and glass wool.