Nano - thermal insulation board is a kind of high-efficiency thermal insulation material newly developed in the United States and some European countries in the 1980s and 1990s. the pore volume fraction of nano-thermal insulation board is generally higher than 90 %, the density is low, and the size of the solid skeleton and pores are less than 100 nm. the structural characteristics of nano-thermal insulation board determine that it has very low thermal conductivity: the cumulative heat transfer area of nano-skeleton is small, which inhibits the solid heat conduction; The movement of gas molecules is limited in a very small space, heat transfer between each other through collision is greatly inhibited, the contribution rate of gas heat conduction is significantly reduced; The introduction of infrared barrier components ( opacifiers ) in the nano heat shield can significantly inhibit radiation heat transfer. Therefore, the thermal conductivity of nano-thermal insulation board at room temperature and pressure is only 0.012 w / ( m k ), less than half of the static air [ 0.026 w / ( m k ) ] under the same conditions, significantly lower than other types.
Fig. 1 is a comparison of thermal conductivity of nano heat insulation board produced by Jinshi company and other heat insulation materials. it can be seen that the thermal conductivity of nano heat insulation board is much lower than that of traditional heat insulation materials, especially with the increase of temperature, the thermal conductivity of nano heat insulation board is obviously lower than that of other heat insulation materials. at present, the nano heat insulation board produced by our company can be processed into various shapes and is suitable for different use environments. as can be seen from fig. 1, the thermal conductivity of nano heat insulation board at high temperature is 1 / 4 of that of that of common heat insulation materials, and the heat insulation efficiency is greatly improved. This means that in the same heat transfer control, the thickness of the nano heat insulation board is much smaller than that of the traditional heat insulation materials, as shown in figure 3. this volume advantage is particularly important in the environment where the space and overall quality are strictly limited, and is also an important factor for designers to give priority to.

The appearance of nano thermal insulation panels has attracted the attention of military industry and other high-tech fields. Nasa, for example, has used the material for thermal insulation in space applications. In the past, organic foam materials and inorganic mineral fiber products were the main application of marine thermal insulation materials, but these materials had some defects such as flammability, temperature resistance and toxicity of organic foam, which inhibited its application. But the traditional inorganic mineral wool product has poor heat insulation performance, so its heat insulation efficiency is low. So the u s naval research laboratory has been doing research to improve the thermal insulation materials for ships. The results show that min - k light shielding material ( a brand of nano heat insulation board ), organic poly ( aryl oxy - phosphazene ) foam and polyimide foam are the most promising heat insulation materials for ships, among which the performance of min - k material is the best. At present, in foreign shipping industry, nano heat insulation board is mainly used in naval ships and other high-grade ships.
1, As refractory separation
Nano - thermal insulation panels have the great advantage of greatly saving space and weight when used as refractory partitions. The thickness of that nano heat shield when use as a refractory partition for a - 60 grades with aluminum silicate fib and rock wool is shown in table 4. Although the above is the comparison between insulation core material, but still can see its advantage of insulation effect. This is also the main application in ships.

2, Used for pipeline heat insulation
The thickness of a - 60 fire-resistant insulation using nano-thermal insulation board as insulation for ship high-temperature pipeline is better than that of thermal insulation. Because the insulation effect of the pipe is also related to the surface area of the insulation layer. The thicker the insulation layer, the larger the external surface area, even if the surface temperature is the same, but its corresponding heat dissipation is increased. Now at 500 ℃ under the condition of pipe diameter is 150 mm high temperature pipe, for example, nano insulation board and mineral wool insulation effect on such as table 5.

3, The application in other occasions
The nano heat insulation board can also be use as a heat insulation material of a submarine enclosure, a protective screen of a ship power device, a cabin heat insulation, an aluminum alloy structure of a ship superstructure, a fireproof protective lay on that surface of the glass fiber reinforced plastic structure and the like. And h - class fire resistance of offshore platforms. Conclusion since the appearance of nano-thermal insulation board, it has attracted the attention of shipbuilding and naval departments in the United States, Britain and other developed countries, and has become its main application. But at present this kind of material in our country is just beginning to explore stage, has not yet come out of the product. Therefore, it is hoped that the marine industry in China will speed up the development of nano thermal insulation panels suitable for marine applications. At present, the eleventh research institute of China shipbuilding industry is cooperating with the relevant units to carry out this research work, and has made some progress. Strive for as a new material, new technology, new technology and early application in China's naval undertakings.
In order to realize the popularization and application of nano heat insulation board in ships, the following problems must be solved.
1. the stability of nano thermal insulation panels in ship operation environment. The influence of ship operation on the overall structure, performance and subsequent maintainability of nano heat shield components must be strictly evaluated.
2, the moisture-proof problem of nano heat insulation board. Nano - thermal insulation board is easy to absorb water vapor in the air and lead to pulverization, cracks and other phenomena, affecting its performance and subsequent maintenance. Therefore, it is one of the problems in the application of nano thermal insulation panels to develop a simple waterproof ( moisture ) technology for nano thermal insulation panels.
3, the cost of the problem. The demand for heat insulation materials for ships is huge, and the requirement for reducing the material cost is high. whether the low-cost preparation technology of materials can be broken through to reach the affordable range will also become an important problem that must be solved.
4, safety protection problems. Ceramic nanoparticles and fibers are contained in the composition of the nano heat insulation board, which may generate dust during construction and maintenance. therefore, the elimination method of dust and its impact on human health must be considered.
After decades of research and development in foreign countries, nano heat shield has been successfully applied in power, metallurgy, chemical industry, nuclear energy, ships and other fields, and has passed the test of different working environment, its excellent comprehensive performance has been proved by practice. Marine thermal insulation materials have been paid much attention to in the design and construction of ships. the promotion and application of nano thermal insulation panels in the field of marine thermal insulation will undoubtedly promote the overall performance of ships in China.