Lee, He Seung Choi, Seung-Sock Baek, Kyung-Youl Hong, Soon Man Lee, Eung Chan Lee, Jong-Chan Hwang, Seung Sang 2024-01-20T14:34:03Z 2024-01-20T14:34:03Z 2021-09-05 2012-06 0014-3057 https://pubs.kist.re.kr/handle/201004/129209 The stereo cyclic siloxane compounds having tetra hydroxyl and tetra methyl group were synthesized by hydrolysis of tetrahydrido tetramethyl cyclosiloxane consisting of four stereoisomers. Among the stereo cyclic isomers, cis-trans-cis tetrahydroxyl tetramethyl cyclosiloxane (2) was separated by recrystallization and was used as a monomer species for preparation of ladder-like polymethylsilsesquioxane (PMSQ). The isolated isomer was directly polymerized in THF with potassium carbonate (K2CO3) by systematic ring condensation. The hydrolyzed stereoisomers were characterized by H-1 and Si-29 NMR, and HPLC. The structure of the synthesized PMSQs were characterized by size exclusion chromatography (SEC), MALDI-TOF mass, Si-29 NMR, and small angle X-ray scattering (SAXS). (C) 2012 Elsevier Ltd. All rights reserved. English PERGAMON-ELSEVIER SCIENCE LTD ANGLE X-RAY NEUTRON-SCATTERING POLYMER-MOLECULES POLYCONDENSATION PHENYLSILSESQUIOXANE SILSESQUIOXANES CONFORMATION RIGIDITY Synthesis and structure characterization of ladder-like polymethylsilsesquioxane (PMSQ) by isolation of stereoisomer Article 10.1016/j.eurpolymj.2012.03.008 1 EUROPEAN POLYMER JOURNAL, v.48, no.6, pp.1073 - 1081 EUROPEAN POLYMER JOURNAL 48 6 1073 1081 scie scopus 000304849400007 2-s2.0-84861199754 Polymer Science Polymer Science Article ANGLE X-RAY NEUTRON-SCATTERING POLYMER-MOLECULES POLYCONDENSATION PHENYLSILSESQUIOXANE SILSESQUIOXANES CONFORMATION RIGIDITY Polymethylsilsesquioxane Stereoisomer Polycondensation Silsesquioxane Ladder-like