Synthesis of Di- and Triblocks of Butadiene-Dimethylsiloxane Using High Vacuum Anionic Polymerization Techniques

A.E. CIOLINO; D. PANTAZIS; M.A. VILLAR; E.M. VALLÉS; N. HADJICHRISTIDIS

Gramado, Brasil

Simposio; X International Macromolecular Colloquium; 2005

Instituto de Química, UFRGS y ABPol

Model di and triblock copolymers of butadiene-dimethylsiloxane (PB-b-PDMS and PB-b-PDMS-b-PB, respectively) were synthesized using high vacuum anionic polymerization techniques. Diblocks were synthesized by sequential addition of monomers, while triblocks were obtained by coupling the living polymer chains with 1,2-bis (chlorodimethyl silyl) ethane. The relative molecular weights of the samples and the mol fraction of the corresponding blocks were determined by size-exclusion chromatography (SEC) and nuclear magnetic resonance (1H-NMR ), respectively. According to the experimental results, PB-b-PDMS and PB-b-PDMS-b-PB with narrow molecular weight distributions (model copolymers) and defined compositions were obtained