Bifunctional phosphazene-thiourea/urea catalyzed ring-opening polymerization of cyclic esters
Source abstract
Abstract
Abstract A series of new bifunctional phosphazene-thiourea/urea catalysts have been designed and applied to ring-opening polymerization (ROP) of rac-lactide, δ-valerolactone and e-caprolactone. The ROPs were promoted efficiently, delivering the corresponding polyesters with controlled molecular weights, narrow molecular weight distributions, well-defined end group fidelities and without undesired epimerization of rac-lactide. Kinetic experiment of rac-LA confirmed the controlled/living nature of the ROP process. The isoselective polymerization of rac-LA was achieved with a highest Pm value of 0.79 (based on Bernouillan statics) under mild conditions. In addition, the ROPs of δ-VL and e-CL were also smoothly achieved with high conversions and narrow molecular weight distributions. These catalysts exhibit a broad monomer scope of lactones, providing a facile synthesis methodology of metal-free and applicable polyester materials.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: biodegradable polymer synthesis and properties · Carbon dioxide utilization in catalysis · Polyoxometalates: Synthesis and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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