Conductive nanocomposites manufactured via frontal polymerization

Frontal polymerization (FP) is a rapid, energy-efficient alternative to conventional manufacturing techniques for polymers and polymer composites. FP has been demonstrated for several polymerization reactions. One of the most promising is the frontal ring-opening metathesis polymerization (FROMP) of dicyclopentadiene (DCPD), which produces polydicyclopentadiene (pDCPD), a cross-linked thermoset polymer with excellent thermomechanical properties. Here we report for the first time the manufacturing of pDCPD matrix nanocomposites via FROMP. First, we describe nanocomposites containing low loadings of carbon nanofillers, below the percolation threshold. The ability of these nanofillers to efficiently convert light into heat enables non-contact photo-activation of FROMP. The efficiency of photo-activation increases by 40× with the addition of only 1 wt% carbon nanoparticles to the neat DCPD resin. Next, we describe nanocomposites containing higher loadings of carbon nanofillers, above the percolation threshold. These nanocomposites exhibit electrical conductivity more than 18 orders of magnitude greater than neat pDCPD. At loadings above the percolation threshold, the nanofillers also function as rheological modifiers which enable direct write 3D printing of the resin in tandem with FROMP.