Triblock copolymers and pentablock terpolymers of n‐hexyl isocyanate with styrene and isoprene: Synthesis, characterization, and thermal properties

Triblock copolymers and pentablock terpolymers of n‐hexyl isocyanate (H), styrene (S), and isoprene (I) of the type HSH (six samples, Mn:49–163 K, weight % of H:5–59), HIH (two samples, Mn:75 and 83.4 K, weight % of H:16 and 40), HSISH (one sample, Mn:79.4 K, weight % of H:13), and HISIH (one sample, Mn:128 K, weight % of H:25) were synthesized by high‐vacuum techniques in tetrahydrofuran at −98 °C with the sodium naphthalene/sodium tetraphenylborate initiating system. All materials were characterized by size exclusion chromatography, membrane osmometry, and 1H NMR. The combined molecular characterization results revealed a high degree of molecular and compositional homogeneity. The thermal properties of the synthesized materials were examined by thermogravimetric analysis and differential scanning calorimetry.