Thermosets printed using additive manufacturing (AM) technologies are often brittle, often making the resulting polymers unsuitable for use within structural applications or as end-use products. Secondary phase toughening via liquid rubber modification is a common toughening method that has previously been established for use in traditional, thermally cured thermosets. However, this toughening technique has yet to be explored for use within thermosetting photolithography resins. Though the fracture toughness (KQ) of modified thermosets was increased from 0.48 ± 0.01 MPa*m1/2 to 0.82 ± 0.15 MPa*m1/2 when 20 phr of the liquid rubber was incorporated into the resin, both glass-transition temperature and flexural strength were reduced. To supplement this loss in material performance, silica nanoparticles were added into the system as well. Resulting hybrid materials were successfully printed using digital light processing vat photopolymerization. It was found that both thermal and mechanical properties were improved by the presence of the nanoparticles. When used together, a synergistic toughening effect was observed as well.

Additive manufacturing of toughened polymer-Matrix composites using hybrid resin systems

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.