Synergistic toughening of epoxy resin by CTBN and CM-β-CD

Carboxymethyl-beta-cyclodextrin (CM-beta-CD) and carboxyl terminated liquid nitrile rubber (CTBN) were used as binary component fillers in toughening the epoxy resin (E-54). For a single component filler system, the addition of CTBN resulted in significantly improved fracture toughness but reduction of glass transition temperature (T-g) and modulus of epoxy resin. On the other hand, the addition of CM-beta-CD resulted in a modest increase in modulus and T-g, and significant improvement in toughness. This work provides a promising route of nanocomposites with excellent toughness. Besides the mechanism of synergistic toughening in this project was explained, and the major toughening mechanisms were attributed to interfacial micro-cracks, energy dissipation of CM-beta- CD. This work gives us a further understanding of the modification effect of beta- CD.

Automated summary

The addition of CTBN significantly improves the toughness of epoxy resin but decreases its glass transition temperature and modulus, while the addition of CM-β-CD results in a slight increase in modulus and T-g, and a significant improvement in toughness. This work provides a promising pathway for nanocomposites with excellent toughness, with toughening mechanisms attributed to interfacial micro-cracks and energy dissipation of CM-β-CD.