摘要 |
Polyamide is semi-continuously depolymerized by: (a) charging the polyamide to a depolymerization reactor containing 5 to 50% by weight of an unpolymerized catalyst; (b) melting the polyamide and subjecting the resultant melt to a flow of superheated steam to obtain a steam distillate; (c) separating amide monomers in the distillate from other volatiles therein; (d) when conversion to amide monomers is 40 to 90% complete, recharging polyamide to the depolymerization reactor; and (e) repeating steps (a) - (d) until a desired amount of polyamide is depolymerized.
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