摘要 |
A process for the simultaneous preparation of polyamide-6 with at least two different viscosities comprising prepolymerisation of epsilon -caprolactam and/or other polyamide-6 precursors in the presence of water, wherein at least part of the necessary water is supplied to the prepolymerisation via the gas phase and the obtained prepolymer is progressively moved and treated with an inert gas in at least two condensation reaction zones or reactors, placed in series, and the prepolymerisation and condensation are carried out in reactor(s) or reaction zones having a self-renewing interface between molten phase and gas phase with a large surface/volume ratio of the molten phase and the molten phase is relatively strong mixed.
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