Periodic Reporting for period 1 - BioCore VIP (Development of environmentally-friendly Bio-sources aerogel as the support Core for vacuum insulation panels (VIPs))
Reporting period: 2018-09-01 to 2020-08-31
Thermal insulation is a basic requirement where heat loss or heat gain is a concern, for example, buildings, solar collectors, refrigerators, etc. To reduce the required thickness of insulation, low thermal conductivity is desired. In the recent years, aerogel has emerged as an attractive solution owing to its very low thermal conductivity of around 0.013W/m·K, which is about one-third of the common insulation materials. Polysaccharide-based aerogels are new, sustainable materials, with the potential to transform various industrial processes from petroleum dependent into bio-economic. We have carried out preliminary investigations on bio-sources aerogels prepared from modified KGM and starch to be hydrophobic for hydrophobic property.
The overall aim of the proposed BioCore VIP project is to develop a vacuum insulation panel with eco-friendly bio-sources aerogel as the support core. This bio-sources aerogel will be prepared from natural polysaccharides including konjac glucanmannan (KGM) and those derived from potato starch, chitosan, farm waste, etc. Due to its biodegradable nature, the bio-sources aerogel is a desirable alternative to the conventional silica aerogel. When encapsulated in a vacuum panel, the thermal conductivity of aerogel can be reduced by about a few times due to eliminating convective heat transfer.
The specific objectives of the project are:
i) To investigate the novel use of konjac glucanmannan (KGM) as a skeleton micro-pore structure, and the use of starch, chitosan or other polysaccharides to enhance the mechanical performance of the aerogel. A starch-enhanced KGM aerogel may also have a very good fire-retardant performance.
ii) To control the hydrophilic characteristics of bio-sources aerogel and its degradation rate by formulation, structure modifications and hydrophilic property balance, depending on the application requirement.
iii) To explore the correlations of bio-sources aerogel performances (i.e. thermal insulation and mechanical performances) and its microstructure (i.e. micro-pore structure, size distribution of micro-pore) by regulating the growth of ice crystal and aerogel process conditions, and further to acquire the bio-sources aerogel with desired thermal insulation and mechanical performance.
iv) To establish a procedure to apply the environmentally friendly freeze-drying technique for aerogel preparation, enabling continuous production suitable for industrial scale.
The overall aim of the proposed BioCore VIP project is to develop a vacuum insulation panel with eco-friendly bio-sources aerogel as the support core. This bio-sources aerogel will be prepared from natural polysaccharides including konjac glucanmannan (KGM) and those derived from potato starch, chitosan, farm waste, etc. Due to its biodegradable nature, the bio-sources aerogel is a desirable alternative to the conventional silica aerogel. When encapsulated in a vacuum panel, the thermal conductivity of aerogel can be reduced by about a few times due to eliminating convective heat transfer.
The specific objectives of the project are:
i) To investigate the novel use of konjac glucanmannan (KGM) as a skeleton micro-pore structure, and the use of starch, chitosan or other polysaccharides to enhance the mechanical performance of the aerogel. A starch-enhanced KGM aerogel may also have a very good fire-retardant performance.
ii) To control the hydrophilic characteristics of bio-sources aerogel and its degradation rate by formulation, structure modifications and hydrophilic property balance, depending on the application requirement.
iii) To explore the correlations of bio-sources aerogel performances (i.e. thermal insulation and mechanical performances) and its microstructure (i.e. micro-pore structure, size distribution of micro-pore) by regulating the growth of ice crystal and aerogel process conditions, and further to acquire the bio-sources aerogel with desired thermal insulation and mechanical performance.
iv) To establish a procedure to apply the environmentally friendly freeze-drying technique for aerogel preparation, enabling continuous production suitable for industrial scale.
In this study, we investigated the factors controlling ice crystal growth and their relationships with aerogel porous structure based on the optimum aerogel formula. The morphology of ice crystals formed during pre-freezing was observed by low temperature polarizing microscopy, while aerogel pores were observed by scanning electron microscopy. The impacts of pre-freezing temperatures, KGM and glyceryl monostearate concentrations on ice crystal growth and formation of porous structure in KGM-based aerogels were investigated. This study aims to investigate the relationship between thermal insulation property and pore structure of KGM/starch based aerogels enhanced with wheat straw and gelatin. The impact of aerogel components on the mechanical property, thermal stability, density, porosity of KGM/starch based aero re polarizing microscopy, while aerogel pores were observed by scanning electron microscopy. The impacts of pre-freezing temperatures, KGM and glyceryl monostearate concentrations on ice crystal growth and formation of porous structure in gels was also studied. This research can contribute to the development of biodegradable thermal insulation materials.
A novel designed freeze drying method was used to produce biomass-based aerogels that can be regarded as sustainable solutions for efficient heat dissipation and thermal insulation applications in the construction industry. The environmental impacts of the process could be reduced further by incorporating the use of equipment with higher energy efficiency, using renewable energy sources for fulfilling the electricity need and reducing the processing time. Moreover, the production of larger batches of the product will also facilitate in improving sustainability and environmental efficiency.
A novel designed freeze drying method was used to produce biomass-based aerogels that can be regarded as sustainable solutions for efficient heat dissipation and thermal insulation applications in the construction industry. The environmental impacts of the process could be reduced further by incorporating the use of equipment with higher energy efficiency, using renewable energy sources for fulfilling the electricity need and reducing the processing time. Moreover, the production of larger batches of the product will also facilitate in improving sustainability and environmental efficiency.
Five milestones are achieved as the followings: 1) M1, Structure modification of konjac glucomannan (KGM); 2) M2, Preparation of KGM-based or KGM/starch based aerogels; 3) M3, the microstructure, mechanical behaviours, hydrophobicity, thermal conductivity and degradation of produced aerogels.; 4) M4, economic and environmental analyses; 5) M5, Patent application, dissemination and exploitation activities, and periodical and final project reports.
The achievements will contribute to thermal insulation aerogels in scientific theory and application technology. Application of the new polysaccharide-based aerogels on the eco-materials in Europe could also reduce the required thickness of insulation, thermal conductivity and facilitate environmental sustainable development.
The achievements will contribute to thermal insulation aerogels in scientific theory and application technology. Application of the new polysaccharide-based aerogels on the eco-materials in Europe could also reduce the required thickness of insulation, thermal conductivity and facilitate environmental sustainable development.