I want to try to polymerize with other monomers as well, so I'm not interested in the ring opening polymerization of lactide. Thank you so much! Pictures would be hugely helpful, or any references, as well!
The easiest and very efficient way is by azeotropic polycondensation in solution using a Soxhlet extractor packed with activated 4A molecular sieves. The best results are achieved with xylenes as solvent (20% w/v) and a binary equimolar mixture of SnCl2*2H2O and p-toluenesulphonic acid (0.5 wt% with respect to the overall weight of AHA monomers).
Polycondensation is carried out in boiling solvent, at 140-145 degC. Water formed during the reaction is removed from the reaction vessel as an azeotrope (bp. < 100 degC) and subsequently absorbed by molecular sieves; a dehydrated solvent is then returned to the vessel. The reaction proceeding for 12 h yields a PLA polymer with Mn = 15-20 kDa and optical purity exceeding 95% if L-lactic acid is used as monomer.
Dear Pawel P. Sobecki;
would you please refer me to any reference which use the procedure you given in you answer. It seems interesting for me in a similar work, since Soxhlet is used for azeotropic distillation instead of a conventionnal Dean-Stark glassware. Regards
Azeotropic method includes solvents. If you want eco-friendly bulk polymerization without solvents, The common solution is making vacuum. I also adding my publicitaions.
Article Synthesis and Characterization of Poly (L-Lactic Acid)/Clay ...
Article Preperation of Poly (Lactic Acid) Nanocomposite via Catalyst...
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