Fabrication of PLCL Block Polymer with Tunable Structure and Properties for Biomedical Application.

Biodegradable materials are pivotal in the biomedical field, where how to precisely control their structure and performance is critical for their successful translational application at clinical level. In this study, poly (L-lactide-b-ε-caprolactone) block copolymers (bPLCL) with well-defined segment structure are obtained by a first synthesis of PCL soft block, followed by ring opening polymerization of lactide to form PLA hard block. The pre-polymerization allows for fabrication of bPLCL with the definite compositions of soft/hard segment while preserving the individual segment of their special soft or hard segment. These priority makes the bPLCL afford biodegradable polymer with better mechanical and biodegradable controllability than the random PLCL (rPLCL) synthesized via traditional one-pot polymerization. 10 mol% CL introduction can result in a formation of an elastic polymer with elongation at break of 286.15 ± 55.23%, while the rPLCL still remains the brittle feature of PLA with low elongation at break of 6.42 ± 1.49%. Also, bPLCL preserves the unique crystalline structure of the soft and hard segments to present a more sustainable biodegradability than the rPLCL which has a disordered structure due to the random CL/LA distribution. Furthermore, compared to the random polymerization, the pre-polymerization technology results in a formation of bPLCL with higher yield with the actual composition ratio. The combinative merits make the pre-polymerization technique a promising strategy for a scalable production of PLCL materials with good compatibility for potential biomedical application in the future. This article is protected by copyright. All rights reserved.