Combination of Condensation and Ring-Opening Polymerization

It was shown that lipases can catalyze enzymatic ROP and polycondensation simultaneously. This lipase ability was employed in order to obtain various polyesters. 

The copolymer of 12-hydroxydodecanoic acid/P-butyrolactone was synthesized at 45 °C in toluene, using Porcine pancreatic lipase [29], After 72 h, the molecular weight of the obtained copolymer in 70% yield was M = 1800. Electrospray 

Iwata et al. [120] used Novozym 435 to catalyze copolymerizations of e-CL with 11-mercaptoundecanoic acid (11MU) and 3-mercaptopropionic acid (3MP). The same authors also demonstrated that Novozym 435 catalyzed transesterifications between poly( -CL) and 11-mercaptoundecanoic acid or 3-mercaptopropionic acid in o-xylene. 

This chapter provides numerous examples of significant advancements documented in the literature describing cell-free enzyme-catalyzed polymerizations, predominantly using lipases as catalysts. Polymerization reactions occurred by (i) condensations (ii) ring-opening homo- and copolymerizations and (iii) combination of condensation and ring-opening polymerization. 

Lipase-catalyzed synthesis of polyesters came to the focus after two major breakthroughs in 1984, novel lipase-catalyzed polycondensation to give oli-goesters in 1993, discovery of the catalysis for ring-opening polymerization of lactones. 

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