The synthesis and thermal polymerization of 4,4′-diethynylphenyl ether

Diethynylphenyl ether (DEPE) was synthesized and its thermal polymerization studied by NMR, IR, and DSC techniques. DEPE is a crystalline solid that melts at 72–73°C and undergoes polymerization beginning at about 150°C. The heat of polymerization measured by DSC was 53 ± 2 kcal/mole. Thermomechanical analysis (TMA) of the fully cured resin showed softening behavior at temperatures in excess of 400°C. Weight loss up to 720°C was only 21%. A mechanism of polymerization based on the analysis of IR and NMR data for party polymerized material below 300°C is proposed.