mz8b00039_si_001.pdf (891.06 kB)
Well-Defined Selenium-Containing Aliphatic Polycarbonates via Lipase-Catalyzed Ring-Opening Polymerization of Selenic Macrocyclic Carbonate Monomer
journal contribution
posted on 2018-02-22, 18:50 authored by Chao Wei, Yue Xu, Bingkun Yan, Jiaqian Hou, Zhengzhen Du, Meidong LangThe synthesis of well-defined, biodegradable
selenium-containing
polymers remains a formidable challenge in polymer chemistry. Herein,
a selenic cyclic carbonate dimer monomer (MSe) was developed
to generate well-defined, biodegradable aliphatic polycarbonates with
selenide functionality on the backbone. The monomer was synthesized
via the intermolecular cyclization of di(1-hydroxyethylene) selenide
and diphenyl carbonate with lipase CA as catalysts in a mass of anhydrous
toluene with very dilute monomer concentration. Then living ring-opening
polymerization (ROP) was executed by solution method using the same
lipase CA as catalysts. Similarly, the copolymerizations with commercial
trimethylene carbonate (TMC) generated random copolymers demonstrated
by 13C NMR, regulating the density of selenium functional
groups. The resulting polymers exhibited a living polymerization characteristic,
as evidenced by polymerization kinetics, predictable molecular weights,
narrow molecular-weight distribution, and controlled copolymer compositions.
Using hydrophilic macroinitiators (PEG), amphiphilic di/triblock copolymers
could be obtained, suggesting their potential as controlled drug delivery
system (DDS) and hydrogel scaffolds for tissue engineering.