| 摘要 |
PURPOSE:A heat accumulative material having sufficient durability to the repetition of heating and cooling, not causing sticking of the heat accumulative material to one another by fusion, being handled easily, obtained by covering the surface of a molded polyolefin resin with a carbonaceous film. CONSTITUTION:Polyolefin resin is molded into spheres having diameters of 10- 20mm., granules having the minor diameter of 5-30mm. and the major diameter of 10-100mm., or pellets having diameters of 5-30mm. and length of 10-150mm., the resin is brought into contact with conc. sulfuric acid (preferably at a temperature < the melting point of the resin and near to it as closely as possible for 1min-3hr) so that a carbaneous layer is formed on the surface of resin, heated further so that the thickness of the resin film is made preferably 0.1-1mm., kept at high temperature (preferably >= the melting point of the resin, a temperature to make sufficiently the resin in a molded article in a swelling state), and cooled as quickly as possible, to give the desired heat accumulative material. |
