In the present work various sets of vinyl- and hydride-containing precursors are explored for aerogels synthesis via hydrosilylation route directly in supercritical CO2. The means to control the target mechanical properties of aerogels by changing the precursors composition are proposed. Aerogels with Young's modulus as low as 3.6 kPa can be obtained using hyperbranched silsesquioxane hydrides, while the use of tetraallylsilane with a linear hydride-containing oligomeric siloxane allows synthesis of aerogels with Young's modulus in the range of 40-124 kPa. (C) 2019 Elsevier B.V. All rights reserved.