Anionic polymerization of norbornene trisulfide (exo‐3,4,5‐trithia‐tricyclo[5.2.1.02.6]decane)

The anionic polymerization of norbornene trisulfide initiated with sodium thiophenoxide (sodium cation solvated with dibenzo‐18‐crown‐6 ether) was studied. Polymers with high molecular weights were obtained (Mn up to 105, osmometrically). Molecular weights calculated for living polymerization conditions (i.e., one molecule of initiator yields one macromolecule) agree well with Mn measured by osmometry. 1H‐NMR, 13C‐{1H}‐NMR, and Raman spectra of the polymer are given. Thermodynamics of polymerization in toluene solvent is described. Enthalpy ΔHss = −(1.39 ± 0.17) kcal mol−1 and entropy ΔSss = −(7.52 ± 0.55) cal mol−1 deg−1 coefficients of polymerization were evaluated from the temperature dependence of the equilibrium monomer concentration determined dilatometrically.