Organosilane polymers of the type (SiR1R2)n were prepared by dehydrochlorination of R1R2SiCl2 (R1 = Me; R2 = H, Et, Prp, But, Hex, Oct, Ph) with sodium in toluene as solvent. The decomposition temperature, yield, soldubility and appearance were found to depend strongly on molecular structure. The pyrolysis of poly(methylsilane) was found to give a 60 % ceramic yield after thermal processing at 750°C.