Polylactones synthesis by enzymatic ring opening polymerization in flow

Polycondensation in batch is the classical way to produce polyesters. However, this method requires harsh conditions reach high conversions and drive equilibrium of reaction forward. In order controlled polymers a greener way, we worked on enzymatic ring opening polymerization (e-ROP) lactones using CALB lipase immobilized porous beads (Novozym® 435) as catalyst 3-phenyl-1-propanol (PP) initiator flow tubular reactor made fluorinated ethylene propylene (FEP) tubing with i.d = 1.55 mm. short residence time 214 s ε-caprolactone (CL) was fully polymerized (conv 100 %) fair dispersity (Đ 1.30). Polymerization δ-valerolactone (VL) 93 %, Đ 1.27) well copolymerization CL VL mixtures up 88 1.24) behaved similarly. By alternating lactones, block-polymer obtained. As expected, primary alcohols were more efficient than secondary ones for initiating e-ROP lactones. Very interestingly, cholesterol induced formation cyclic polylactones only. addition, showed importance at long formed polymer depolymerized by enzyme. We demonstrated also that enzyme may be reused ten times maintaining its efficiency. The whole study shows use performing improves control shown low values decreases needed compared similar reactions batch.