High-vacuum Low-temperature Insulation Materials

Vacuum insulated panels (VIPs) are distinguished by their relatively thin thermal insulation layers, about 20mm, and their outstandingly low thermal conductivity, which is approximately 4×[10.sup.-3] W/(m·K) to 1×[10.sup.-2] W/(m·K) .only 33% to 10% that of the traditional heat preservation materials. The excellent heat preservation property and its thin thermal insulation layers make it an ideal heat preservation material, which can be used in such fields as refrigerator, cold store, refrigerated container, medical incubator, aviation and architecture. Presently, many countries in the world are studying for the development and application of VIPs.The heat preservation effect of VIPs is affected by the vacuum pressure inside the VIP, the performance of the core material, the getter, the barrier and so on. Through abundant literature reading and market investigation, the development of VIPs both inside and abroad our country is learned. By analyzing their adiabatic principle, several factors that affect the heat preservation property of VIPs have been listed, and the way to reduce the thermal conductivity of VIPs has been put forward, which has provided a solid theoretical foundation for the manufacturing of TLC-VIP.The manufacturing of TLC-VIP is introduced in a step-by-step manner in the paper, including the selection and making of the core material, the barrier, the getter and so on, the design and the rebuild of vacuum packaging machine specific for TLC-VIP, and the pre-treatment technology which may not only improve the heat preservation property but also prolong the service life of TLC-VIP. The thermal conductivity of TLC-VIP made in our laboratory is about 0.01 W/(m·K) tested by an authoritative institution, which is much better than the traditional heat preservation materials. The experiment sector in the paper has provided important gist for optimizing the manufacturing parameters of TLC-VIR Using the thermal conductivity testing apparatus, the thermal conductivity of TLC-VIPs under different vacuum pressure can be obtained, which may help to summarize the gist for the selection of different materials and the determination of the manufacturing parametersBy analysis and calculation, with this kind of TLC-VIPs applied to refrigerated containers, its exciting properties can not only meet the intensity requirement, enlarge the ship load due to its thin thermal insulation layers, but can also save energy consumption by 26.82% compared with polyurethanes, 39.23% compared with extruded polystyrenes, 50.57% compared with rock wool, and 57.54% compared with polystyrenes under the same circumstances. In addition, refrigerated containers with VIPs as the heat preservation material may first reach the set temperature.The excellent heat preservation property of TLC-VIP and its prominent price advantage among the congeneric products have provided a great expectation for the massive production and application of TLC-VIPs.