Synthesis and Characterization of Model Poly(butadiene)-1,4-b- Poly(dimethylsiloxane)-b-Poly(butadiene)-1,4 Copolymers

ANDRÉS CIOLINO; MARCELO VILLAR; ENRIQUE VALLÉS; NIKOS HADJICHRISTIDIS,

JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY

John Wiley & Sons

Lugar: West Sussex , Reino Unido; Año: 2007 vol. 2006 p. 2726 - 2733

0887-624X

Model copolymers of poly(butadiene) (PB) and poly(dimethylsiloxane) (PDMS), PB-b-PDMS-b-PB, were synthesized by sequential anionic polymerization (high vacuum techniques) of 1,3-butadiene and hexamethylciclotrisiloxane (D3) on sec-BuLi followed by chlorosilane-coupling chemistry. The synthesized copolymers were characterized by nuclear magnetic resonance (1H-NMR), size-exclusion chromatography (SEC), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). SEC and 1H-NMR results showed low polydispersity indexes (Mw/Mn) and variable siloxane compositions, whereas DSC and TGA experiments indicated that the thermal stability of the triblock copolymers depends on the PDMS composition. Keywords: anionic polymerization; high vacuum techniques; Polybutadiene-1,4; Polydimethylsiloxane; model triblock copolymers; characterization.