Apparatus and method for separating a cyclic diester from polymer melts

Device for separating and recovering a cyclic diester (I), comprises (a) at least one demonomerizing device for the removal of (I) in gaseous aggregate state of a polymer melt, (b) at least one separating device, which is connected downstream to the demonomerizing device and is in fluid connection with the demonomerizing device, for separating (I), and (c) at least one device, which is connected downstream with at least one separating device, and is in fluid connection with the separating device, for generating vacuum. (I) is transferred over the solid to the liquid aggregate state. Device for separating and recovering a cyclic diester of formula (I), comprises (a) at least one demonomerizing device for the removal of (I) in gaseous aggregate state of a polymer melt, (b) at least one separating device, which is connected downstream to the demonomerizing device and is in fluid connection with the demonomerizing device, for separating (I), and (c) at least one device, which is connected downstream with at least one separating device and is in fluid connection with the separating device, for generating vacuum. (I) is transferred over the solid to the liquid aggregate state. R : H or optionally branched aliphatic 1-6C group. An independent claim is also included for separating and recovering (I) from polymer melts containing (I) with the device, comprising subjecting the polymer melt into at least one demonomerizing device with vacuum, at least partially or completely separating (I) from the polymer melt by transferring to the gaseous aggregate state, transferring the removed gaseous (I) into at least one separating device by cooling to temperatures below the triple point temperature at (a) pressures above the triple point pressure of (I) at a surface of at least one separating device tempered below the triple point temperature in the solid aggregate state, or sublimating the removed gaseous (I) at (b) pressures below the triple point pressure of (I) at surface of at least one separating device tempered below the triple point temperature, transferring into the solid aggregate state, and subsequently condensing and discharging (I) from at least one separating device, where (i) the pressure in at least one demonomerizing device is adjusted to not > 1050 mbar, preferably 1.4-100 mbar, (ii) the pressure in at least one separating device is adjusted to not > 1050 mbar, preferably 1.4-100 mbar during the transfer into the solid aggregate state, (iii) the pressure in