| 摘要 |
<p>1515438 Pelletizing waste polyethylene terephthalate film E I DU PONT DE NEMOURS & CO 14 May 1976 [15 May 1975 12 April 1976] 20003/76 Heading B5A [Also in Division C3] To relcaim waste polyethylene terephthalate or similar polyester film, the film is comminuted and granulated to form laminated binderless pellets of interlocked flakes of the film which can be subjected to drying and solid phase polymerization under vacuum or in an inert gas to increase the intrinsic viscosity to a suitable level for re-processing. The film is shredded into flakes which are fed into a roller and ring pelletizer having a knife to cut the compacted flakes into pellets. The flakes are crimped together at the edges and slightly creped. Slight fusion of the edges may also occur due to friction during passage through the die holes.</p> |
