| 摘要 |
<p>The process, using a semi-crystalline polymer in an amorphous state and with a slow rate of crystallisation, consists of plasticizing the polymer by heating it rapidly to a temperature below its melting point, forcing the plasticized polymer through a die, sweeping it as it leaves the die with a hot, dry inert gas such as nitrogen or carbon dioxide, collecting the plasticized polymer in a first container while maintaining its temperature at the plasticization level, and die-stamping it in the first container (6) or in a second one (9) after transfer from the first, accompanied by a sharp reduction in temperature to obtain a preform in an amorphous state. The apparatus used for the process consists of a polymer plasticizing chamber (3) with a surrounding heater, a feeder, a die (4) with an inert gas input (11) beneath it, a container (6) to collect the plasticized polymer, carried with others on a rotating disc (8), and a die stamper (7).</p> |
