| 摘要 |
A process for producing a novel porous shaped product of light weight, low thermal conductivity and good heat resistance, which comprises firing a shaped article of a mixture comprising fine amorphous silica particles and carbon powder or precursor therefor, substantially free of water, at a temperature at which the carbon powder undergoes oxidation and combustion, thereby welding the silica particles to one another at their contact points and obtaining a sintered product having fine pores formed among the silica particles at their non-contact points. The heat resistance of the shaped product can be further promoted by incorporating an alkali compound in the shaped article and slowly cooling the shaped article after firing. Water repellency can be imparted to the shaped product by incorporating a magnesium compound into the shaped article and subjecting the fired shaped article to a hydro-thermal reaction. Inorganic fibres may also be incorporated. In an application, piping for liquefied natural gas is insulated with three layers of a sintered product. |
