Ring-Opening Polymerization of Dilactide with Cationic Initiators in Solution

Example 3.25a Ring-Opening Polymerization of Dilactide with Cationic Initiators in Solution 

Safety precautions Before this experiment is carried out, Sect. 2.2.5 must be read as well as the material safety data sheets (MSDS) for all chemicals and products used. 

NOTE L-Lactide is hygroscopic and should be stored over P4O10. 

5 g of L-lactide, 50 ml of pure toluene, and a magnetic stirrer are placed in a reaction vessel that has been flamed under vacuum and flushed with nitrogen. The vessel is closed with a pressure-tight rubber cap and heated to 110°C in an oil bath. 0.5 ml of initiator solution (3.32 g of SnC /lOO ml of toluene) is then injected 

Among the various lactones, s-CL is the most extensively studied monomer. The ROP was induced by many lipases from different origin. Candida antarctica [lipase CA or CA lipase B (CALB) immobilized on an acrylic resin, produced commercially as Novozym 435] was found to be the most effective lipase for the ROP of e-CL. 

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