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. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3094–3102, 2003 Triblock copolymers and pentablock terpolymers of n‐hexyl isocyanate (H), styrene (S), and isoprene (I) of the type HSH, HIH, HSISH, and HISIH were synthesized by anionic polymerization techniques and characterized by several methods. The thermal properties of the synthesized materials were examined by thermogravimetric analysis and differential scanning calorimetry. The middle block is styrene (S) or isoprene (I) homopolymers(triblock copolymers) ISI or SIS triblock copolymers(pentablock terpolymers).