US 11,718,711 B2
Method and facility for producing polylactide (PLA) from a lactide mixture by means of polymerization
Reinhard Koch, Gröditz (DE); Dirk Berthel, Rosswein (DE); and Joachim Müller, Frankenberg (DE)
Appl. No. 17/418,332
Filed by Reinhard Koch, Gröditz (DE)
PCT Filed Feb. 18, 2020, PCT No. PCT/DE2020/100113
§ 371(c)(1), (2) Date Jun. 25, 2021,
PCT Pub. No. WO2020/177810, PCT Pub. Date Sep. 10, 2020.
Claims priority of application No. 10 2019 105 335.8 (DE), filed on Mar. 4, 2019.
Prior Publication US 2022/0064370 A1, Mar. 3, 2022
Int. Cl. C08G 63/08 (2006.01); B29C 48/92 (2019.01); B29C 48/00 (2019.01); B29C 48/44 (2019.01); C08G 63/78 (2006.01)
CPC C08G 63/08 (2013.01) [B29C 48/022 (2019.02); B29C 48/44 (2019.02); B29C 48/92 (2019.02); C08G 63/785 (2013.01); B29C 2948/92019 (2019.02); B29C 2948/92209 (2019.02); B29C 2948/92514 (2019.02); B29C 2948/92704 (2019.02)] 10 Claims
OG exemplary drawing
 
1. A process for producing polylactide (PLA) from a lactide mixture by polymerization, wherein the lactide mixture to be processed is introduced into a planetary gear extruder, and mixed with at least one catalyst and the finished PLA is taken off at an end of the process,
comprising:
passing the lactide mixture continuously through a plurality of segments (35) of the planetary gear extruder (1) having a modular construction, wherein measurements and targeted control of the reactions proceeding in the planetary gear extruder (1) are carried out in the segments (35) such that a temperature can be set by heating and/or cooling as a function of temperature values to be tested via sensors for measuring the temperature values and a pressure can be variably set via a controllable offtake of gas and/or a controllable extruder speed and/or a static alterability of the planetary gears and/or an alterable metering rate of the lactide mixture and/or an alterable mixing ratio of the lactide mixture as a function of pressure values to be tested via sensors for measuring the pressure values,
carrying out the offtake (6) of gas which presents a fire hazard at least in a subregion of the planetary gear extruder (1) in an explosion-protected zone (5),
introducing the at least one catalyst (27) directly into the planetary gear extruder (1) during the rolling process, and
introducing additives (26) for influencing the final properties directly into the planetary gear extruder during the rolling process.