| 摘要 |
Pure polymer, such as polyester used in photographic film and in plastic walls of drink bottles or polycarbonate used in high-quality plastic beverage bottles, is separated from thin saran and like coating layers of a multi-layer film or sheet in a dry process. The coating layer is typically 1/2% or less of the total sheet or film thickness. The dry abrasion process in one form comprises rotating and mixing a volume of dry plastic chips of said film or sheet with about two volumes of small, hard abrasive particles such as quartzite aggregate, glass cullet, or the like, for a time just sufficient to abrade the thin coating layer from the film or sheet. The abrasive particles and the coating dust are separated from the pure polymer by air classifiers. The resulting polymer chips are clean and dry and are immediately available for pelletizing and reuse. Polymer may also be recovered from the dust, as by electrostatic separation.
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