China HKUST developed a new type of fire insulation composite airgel dual network

Recently, the University of Science and Technology of China Yushu Hong Task Force chitosan as a three-dimensional soft template, developed a phenolic resin (PFR) synthesis of new strategies and co-SiO2 and nano-scale phase separation, the successful production PFR having a double network structure / SiO2 composite aerogels materials. Industrial building and maintaining a comfortable indoor temperature of the world\’s total energy consumption each year more than 30% of total energy consumption, the use of insulation materials can improve building energy efficiency, reduce energy consumption. Traditional organic insulating materials generally flammable, the use of organic flame retardants on the environment and human health hazards, thermal conductivity inorganic insulation materials are generally high. The general organic-inorganic composite insulating material, although the flame retardancy is improved, but still difficult to flame erosion resistant long, because no unit club monodispersed state with the polymer matrix and burning off gradually, so that lose protection. Yushu Hong research group developed a dual network structure of the composite airgel dendritic microstructure, less than 20 nm in size of the fibers, and the two components are each a continuous network, organic, inorganic components nanoscale uniform dispersion, while between the two components has a strong interfacial interaction. Researchers addition amount of the silicon source regulation of the physical parameters of density, inorganic content, the mechanical strength of the airgel composite can be regulated. Such airgel composite can withstand, without rupture of 60% compression, a certain mechanical strength and workability. The airgel has good insulating effect, the lowest thermal conductivity of up to 24mW / mK, better than the traditional materials such as expanded polystyrene, at a relatively low temperature and low humidity environment, thermal conductivity was maintained at 28mW / mK. This unique dual network structure gives excellent fire retardant properties of aerogels. Researchers propane-butane burner flame (1300 deg.] C) and the alcohol lamp flame (500-600 deg.] C) to detect fire resistance aerogels, and the temperature change of the back surface of the sample by infrared thermography were recorded. After 30 minutes the test, the sample back surface temperature of the burner flame stabilized at about 300 ℃, alcohol lamp flame temperature stabilized at about 150 deg.] C, and with the combustion of the organic components, SiO2 network and exposed surface adhered airgel will not fall off, continue to play the role of isolated heat. This material can avoid failure load-bearing structure of the building when the fire broke out to a certain extent,For the evacuation for a time. Research results published in the \”German Applied Chemistry\”, postdoctoral Yu Zhilong is the first author of the paper. The research was supported by the National Natural Science Foundation of Innovative Research Groups, the National Natural Science Foundation of China Foundation, a major national scientific research plan, Chinese Academy of frontier science research projects, Chinese Academy of nano-science innovation center of excellence, innovation and technology center in Suzhou Nano collaborative, Hefei Supporting Science Center of Excellence user funds. 中国科大研制出新型隔热防火双网络复合气凝胶 中国科大研制出新型隔热防火双网络复合气凝胶 PFR double network structure / SiO2 airgel preparation process of the composite structure and a schematic view