Synthesis and structure characterization of ladder-like polymethylsilsesquioxane (PMSQ) by isolation of stereoisomer

► Isolation of cis-trans-cis cyclic siloxane stereoisomer which having four methyl and four hydroxyl groups. ► Isolated isomer was directly polymerized by hydrogen bond induced ring condensation. ► The polymer (PMSQ) was analyzed to be of ladder-like structure.