US 12,269,920 B2
Continuous glycolide-L-lactide copolymer production process development
Erman Senoz, Somerville, NJ (US); Sasa Andjelic, Somerville, NJ (US); and Marc Brian Wisnudel, Somerville, NJ (US)
Assigned to Ethicon, Inc., Raritan, NJ (US)
Filed by Ethicon, Inc., Somerville, NJ (US)
Filed on May 6, 2021, as Appl. No. 17/313,506.
Claims priority of provisional application 63/022,981, filed on May 11, 2020.
Prior Publication US 2021/0355273 A1, Nov. 18, 2021
Int. Cl. C08G 63/78 (2006.01); C08G 63/08 (2006.01); C08G 63/64 (2006.01); C08G 63/82 (2006.01)
CPC C08G 63/785 (2013.01) [C08G 63/08 (2013.01); C08G 63/64 (2013.01); C08G 63/823 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A reaction process for preparing a glycolide/L-lactide copolymer formulation comprising:
(a) continuously introducing 10-95% glycolide monomer, 5-90% L-lactide monomer, initiator and optionally a catalyst into at least one continuous reactor vessel under dry nitrogen environment, wherein the monomers, initiator, and optional catalyst are mixed at a first lower temperature, in the range of 85-95° C. and then,
(b) transferring the mixture continuously to a second continuous reactor operating at a second higher temperature-from about 140-230° C., wherein transferring the mixture into the second continuous reactor is performed through a transfer line, having a transfer line temperature in the range of 85-95° C., and then
(c) exothermally reacting and maintaining at a steady state, the blend of glycolide monomer, lactide monomer, initiator and optional catalyst to produce a PLGA copolymer reaction product,
wherein glycolide, l-lactide, initiator, and optional catalyst are heated and completely melted to a temperature in the range of 85-95° C. in at least two parallel melting vessels and the homogenized contents of the vessels are transferred into the second continuous reactor to provide a continuous flow.