Critical exponents for the sol-gel transition

Abstract

Solutions of tetramethoxysilicon were reacted, using both acid and base as catalysts, until near the sol-gel transition. Portions of the reacting mixture were quenched by dilution, and the average cluster mass and correlation length were measured with use of static and dynamic light scattering. Critical exponents describing the divergences of the average mass and correlation length were found to be larger than the predictions of either the percolation or Flory-Stockmayer theory.