“Well-defined Synthesis of Poly(dimethylsiloxane) Homopolymers”

MARIO D. NINAGO; ÁNGEL J. SATTI; JORGE A. RESSIA; ANDRÉS E. CIOLINO; ENRIQUE M. VALLÉS; MARCELO A. VILLAR

Roma (Italia)

Conferencia; The Ninth International Conference on Chemical and Process Engineering; 2009

Abstract Poly(dimethylsiloxane) (PDMS) is a silicon-based homopolymer that can be regarded as derivative of inorganic silicates by partial substitution with methyl groups. This fact offers a wide spectrum of properties that cannot be offered by common organic polymers, which result from the combination of the polar Si–O backbone with the contribution of the organic groups. Among these properties, we can mention a low glass transition temperature; high gas permeability; usability over a wide range of temperatures; low chemical reactivity; and essentially a non-toxic nature. Therefore, PDMS are used as rubbers, resins, dielectric multimedia, hydraulic or heat transfer fluids, lubricants, medical materials and surfactants among other application. Kinetically controlled polymerization of PDMS is based on anionic polymerization of hexamethyl(cyclotrisiloxane) (D3), and is quite similar to living polymerization. Since the ring opening polymerization of D3 is affected by several parameters (solvent, temperature, reaction time, etc.), in this work we wish to present a method that allows preparing model PDMS polymers with a precise control of molecular weight and molecular weight distributions ranging from 10e3–10e5 g/mol and polydispersity indexes lower than 1.09.