To carry out a solid-phase polymerization of a polyamide of stabilized quality by preventing mutual polyamide chips from fusing and clogging the interior of a vessel.
Nylon 66 chips prepared by heating up the chips subjected to underwater strand granulated(USG) cutting to ≥150°C while stirring the chips and crystallizing the chips so that the crystallinity of the chip surfaces is ≥11% after a liquid-phase polymerization are used as the nylon 66 chips fed to a solid-phase polymerization in the continuous solid-phase polymerization method for the nylon 66 comprising making the nylon 66 chips flow down in the form of a layer, heating the nylon 66 chips at 150-200°C with an inert gas countercurrently fed from the lower side and carrying out the solid-phase polymerization.
MEGATA HIROYOSHI
HORI HIDEO
