Effect of carbon nanotubes on mechanical performance and thermal stability of recyclable thermosets poly(hexahydrotriazine)s-based composites

Abstract A kind of covalent triazine based thermosetting polymer poly(hexahydrotriazine)s (PHT) was synthesized from paraformaldehyde and p-phenylenediamine (PDA) via a straightforward one-pot polymerization. The fabricated PHT shows excellent solvent/thermal resistance and high mechanical stability. Furthermore, the functionalized carbon nanotubes (CNTs) with various contents were incorporated to further improve the comprehensive properties. The composites show enhanced thermal/mechanical stability contrasting to the original polymer. These excellent properties demonstrated that the polymer and its composites were multipurpose materials for the application of automotive, aerospace and other related fields. More importantly, we found that the PHT and its composites could depolymerize at low pH (pH = 0) in different degrees, the PHT can be digested for about 45% at the heating condition (100 °C). Further efforts including other effect factors and methods are currently underway.