Double Quantum NMR Applied to Polymer Networks with Low Concentration of Pendant Chains

R. H. ACOSTA; G. A. MONTI; D. A. VEGA; M. A. VILLAR; E. M. VALLES

MACROMOLECULES

Amercian Chemical Society

Año: 2006 vol. 39 p. 4788 - 4788

0024-9297

p class="BDAbstract" style="MARGIN: 18pt 0cm">The influence of pendant chains at low concentrations in poly(dimethylsiloxane) networks is studied using double quantum proton nuclear magnetic resonance. Small relative variations of the average molecular weight of the elastically active chains, the molecular weight of pendant chains as well as the concentration of pendant chains were analyzed. Changes induced by these defects in the residual dipolar couplings are related to changes in the viscoelastic relaxation times and compared against the behavior of the elastic shear modulus. A very good correlation between NMR measurements and the corresponding rheological experiments is found.