| 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, metal, and other coating layers of a multi-layer film or sheet when the film sheet is wet, as from silver recovery and like processes. The coating layer is typically 1/2% or less of the total sheet or film thickness. The abrasion process in one form comprises rotating and mixing a volume of wet plastic chips of said film or sheet with about three to five volumes of hot (160 to 300 degrees F) small, hard abrasive particles such as quartzite aggregate, glass cullet, or the like, for a time sufficient to dry the chips and also 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 screens or air classifiers. The resulting polymer chips are clean and dry and are immediately available for pelletizing and reuse.
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