Enzymatic ring-opening (co)polymerization of lactide stereoisomers catalyzed by lipases. Toward the in situ synthesis of organic/inorganic nanohybrids

Dueskuenkorur H. O., BEGUE A., POLLET E., PHALIP V., Guvenilir Y., AVEROUS L.

JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC, vol.115, pp.20-28, 2015 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 115
  • Publication Date: 2015
  • Doi Number: 10.1016/j.molcatb.2015.01.011
  • Journal Name: JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.20-28
  • Keywords: Enzymatic polymerization, Lactide, Polyester/clay nanohybrids, EPSILON-CAPROLACTONE, POLYMERIZATION, COPOLYMERIZATION
  • Istanbul Technical University Affiliated: Yes

Abstract

Lipase-based catalysts were tested for the ring-opening polymerization of D-, L- and D,L-lactide isomers, highlighting the different specificity of the enzyme toward these isomers. Free form of Candida antarctica lipase B (CALB) and its clay- and acrylic resin- immobilized forms were compared. For L- and D,L-lactide monomers only short oligomers were obtained. The acrylic resin immobilized form of CALB (NOV0-435) led to a complete conversion of D-lactide to PDLA with a M-n of 2600 g/mol, whereas the clay-immobilized and free forms of CALB exhibited slower kinetics and produced chains of lower M-n. Copolymerization reactions between epsilon-caprolactone and lactide isomers were performed using NOV0-435 as bio-catalyst. Random copolyesters were successfully synthesized by copolymerizing D-lactide with epsilon-caprolactone. Better results were obtained with a two-step reaction, starting from presynthesized polycaprolactone chains, compared with the one-pot copolymerization. Conducting this two-step copolymerization in the presence of organo-modified montmorillonite allowed the successful synthesis of copolymer/clay nanohybrids. (C) 2015 Elsevier B.V. All rights reserved.