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Ring-Opening Polymerization of DD-Lactide Catalyzed by Novozyme 435

✍ Scribed by Marc Hans; Helmut Keul; Martin Moeller

Publisher
John Wiley and Sons
Year
2009
Tongue
English
Weight
236 KB
Volume
9
Category
Article
ISSN
1616-5187

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✦ Synopsis

Abstract

In contrast to LLA, DLA is converted in toluene solution under mild reaction conditions (50–70 °C) using Novozyme 435 (immobilized CALB) to form the corresponding polymer. The influence of several parameters, such as enzyme concentration, temperature and monomer concentration, on the polymerization rate and the monomer conversion was studied. In contrast to the Novozyme 435 catalyzed polymerization of ε‐caprolactone, enzyme deactivation occurs. It is attributed to the deprivation of water from the enzyme. This work points out that by careful selection of the reaction conditions, it is possible to obtain poly(D‐lactide) in reasonable molecular weights and in high yields using Novozyme 435 catalysis.

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