Unique post-functionalization method for ROMP polymers based on Triazolinedione Alder-ene chemistry

Abstract

Triazolinedione (TAD) based Alder-ene reaction was demonstrated as a unique method to efficiently post-functionalize the well-defined polymers derived from living ring-opening metathesis polymerization (ROMP). Using 4-nitrophenyl-1,2,4-triazoline-3,5-dione (p-NO2-PhTAD) as a model TAD compound to react with the double bonds in the backbone of ROMP polymers, the model polymer of poly(N-propyl-5-norbornene-exo-2,3-dicarboximide) (Poly-1) was successfully post-functionalized by grafting the p-NO2-PhTAD functional groups onto the polymer backbone. The TAD based Alder-ene post-functionalization reaction and the resultant p-NO2-PhTAD functionalized Poly-1 were systematically investigated by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). In addition, using a difunctional TAD of 4,4′-(4,4′-diphenylmethylene)-bis-(1,2,4-triazoline-3,5-dione) as a model crosslinking agent, network materials were efficiently produced by crosslinking ROMP derived Poly-1 from TAD based Alder-ene chemistry.