| 摘要 |
PURPOSE:To effectively apply a flash which has been heretofore discarded or incinerated by recovering the flash squeezed out from a mold and introducing it into a kneader and rotating an impeller in a pressurized state to grind it, adding polyolefin, a foaming agent and a crosslinking agent and heating the obtained expandable component in the closed mold at pressurization and thereafter reducing the pressure to produce a foam. CONSTITUTION:Firstly a foaming agent and a crosslinking agent are added to polyolefin and this mixture is kneaded by a heated mixing roll. Then after the obtained expandable composition is filled into a mold and heated, pressure is reduced to obtain a foam. The specified amount of flash squeezed out from the mold in this state is recovered and thereafter introduced into a kneader whose impeller is rotated around a horizontal shaft such as a Banbury mixer and a pressure type kneader and ground while heating it in a pressurized state. Then polyolefin, the foaming agent and the crosslinking agent are freshly added into the ground flash and furthermore this mixture is kneaded to the expandable composition. Then this is filled into the mold and heated at pressurization in a specified time and thereafter pressure is reduced to obtain the foam. |
