The solution properties of several σ-conjugated alkyl-substituted organosilane polymers have been investigated in dilute solution using light and neutron scattering. The particle scattering functions are consistent with those calculated for a wormlike chain with a persistence length, lpers, of approximately 6–7 nm. Measurements have also been done at low temperatures where thermochromic transitions are observed in the electronic absorption spectra. Interpretation of the particle scattering functions at temperatures at or below the transition regions is complicated by the presence of aggregates in the solutions. The results are similar to those observed for ir-conjugated polymers such as the polydiacetylenes in solution. © 1991, American Chemical Society. All rights reserved.