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Alternating Sequence Control for Poly(ester amide)s by Organocatalyzed Ring-Opening Polymerization
Yang Liang1, Jun-Lin Pan1, Lin-Hao Sun1
1Department of Chemistry, College of Science, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.
Macromolecular Rapid Communications
|October 10, 2019
Summary
Organocatalyzed ring-opening polymerization enables precise sequence control in polymer synthesis. This study demonstrates the creation of poly(ester amide)s with controlled sequences, opening new avenues in polymer chemistry.
Area of Science:
- Polymer Chemistry
- Organic Chemistry
Background:
- Sequence-controlled polymerization is a key area in advanced polymer chemistry.
- Achieving precise control over monomer sequence is crucial for tailoring polymer properties.
Purpose of the Study:
- To demonstrate the feasibility of sequence regulation using organocatalyzed ring-opening polymerization (ROP).
- To synthesize pre-organized monomers and subsequently polymerize them to create sequence-controlled poly(ester amide)s.
Main Methods:
- Synthesis of pre-organized monomers using a ring expansion strategy.
- Organocatalyzed ring-opening polymerization (ROP) employing 1,5,7-triazabicyclo[4.4.0]dec-5-ene as catalyst and benzyl alcohol as initiator.
- Characterization of resulting poly(ester amide)s (PEAs) using NMR, MALDI-TOF MS, and DSC.
Main Results:
- Poly(ester amide)s (PEAs) P1-P3 were synthesized with high molecular weights and good yields.
- NMR and MALDI-TOF MS confirmed the microstructural integrity and sequence control of the polymers.
- Differential scanning calorimetry indicated that the PEA without methyl branches exhibited crystallinity.
Conclusions:
- Organocatalyzed ROP is a viable method for achieving sequence control in polymer synthesis.
- The synthesized PEAs possess well-defined sequences and tunable properties, including crystallinity, thermal stability, wettability, and degradation profiles.
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