Continuous emulsion copolymerization processes at mild conditions in a 3D-printed tubular bended reactor

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2018-04, Vol.338, p.311-322
• Main Authors: Bettermann, Sven, Schroeter, Baldur, Moritz, Hans-Ulrich, Pauer, Werner, Fassbender, Marcel, Luinstra, Gerrit A.
• Format: Article
• Language: English
• Subjects: 3D-printed reactor; Continuous emulsion copolymerization; Redox initiation; Thermal imaging
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2018.01.038

[Display omitted] •Suitable and inexpensive tubular bended reactor was 3D-printed.•Geometry led to short and narrow residence time distribution with low dead volumes.•First redox-initiated continuous emulsion copolymerizations in a 3D-printed reactor.•Stable continuous operation leading with grade transition to uniform and adjustable products.•Visualization of polymerization processes by thermal imaging. A polylactic acid tubular bended reactor, printed by fused deposition modeling with a short and narrow residence time distribution, air-cooled, and with dead volumes below 5 vol% was integrated into a modular reaction system enabling product changes in the running system. Continuous, redox-initiated emulsion copolymerizations of styrene - butyl acrylate and of vinyl acetate - neodecanoic acid vinyl ester were successfully performed with 20 and 40 wt% monomer in the feed. Copolymerizations had an ambient starting temperature with a mean residence time of 5 and 15 min, conversions were between 81 and 99%. The resulting emulsions were stable with Zeta potential values up to –132.0 mV and no product adhesion to the reactor wall was found. A stable steady state of the reaction plant was also obvious from thermal imaging, showing an invariant temperature profile along the 3D-printed reactor. The high versatility of the reactor system was shown by a grade transition between the copolymer systems with 20 wt% monomer content.