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Synthesis of Reactive Polyesters Possessing Phenol Pendant Groups Through Selective Ketene/Hydroxyl Addition
1Department of Chemical Engineering, National Tsing Hua University, No. 101, Sec.2, Kuang-Fu Road, Hsinchu, Taiwan.
Macromolecular Rapid Communications
|July 7, 2025
Summary
Researchers synthesized a novel reactive polyester with pendant phenol groups using a Meldrum's acid derivative. This new polymer serves as an effective crosslinking agent for epoxy resins, offering adaptable network properties and recyclability.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Reactive polymers are crucial for synthesizing functional and crosslinked polymers.
- Phenolic compounds are widely used as crosslinking agents in polymer applications.
Purpose of the Study:
- To develop a novel reactive polyester with pendant phenol groups.
- To evaluate the performance of this polyester as a crosslinking agent for epoxy resins.
- To investigate the properties of the resulting crosslinked epoxy networks.
Main Methods:
- Synthesis of a Meldrum's acid derivative (MAHP) monomer.
- Polymerization of MAHP to form a polyester (P-MAHP) via ketene/hydroxyl addition.
- Crosslinking of epoxy resins with P-MAHP and phenolic novolac (PN) for comparison.
- Characterization of polymers and crosslinked resins using techniques like DSC and DMA.
Main Results:
- The synthesized MAHP-based polyester (P-MAHP) exhibited a glass transition temperature (Tg) of 30°C and thermal stability up to 240°C.
- P-MAHP-crosslinked epoxy resin (ER_P-MAHP) showed a lower Tg (102°C) but a higher storage modulus (2.37 GPa) compared to the PN-crosslinked analogue (ER_PN).
- ER_P-MAHP demonstrated features of associactive covalent adaptable networks, including stress relaxation and physical recyclability due to dynamic ester bonds.
Conclusions:
- An effective method for synthesizing reactive polyesters with pendant phenol groups was established.
- The novel polyester serves as a viable crosslinking agent for epoxy compounds, offering tunable properties.
- The development of adaptable networks with recyclability represents significant progress in polymer chemistry and materials synthesis.
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