Functionalizing the incompletely condensed octaphenyl double-decker silsesquioxane tetrasilanol, Ph8-DDSQ(OH)4, with reactive dichlorosilanes forms condensed, hybrid molecules with reactive organic groups on the opposite edge of the inorganic SiO1.5 core, surrounded by phenyl moiety. This unique phenyl moiety surrounded SQ core provides additional thermo-oxidative stability for high temperatures, organic thermoplastics, and thermosetting polymers. Unlike corner-capped functional POSS, condensing DDSQ with dichlorosilane enables different chemical moieties on the opposite side of the SQ core, allowing SQ to act as the "bridging" chemical needed for bonding two different classes of materials. In addition, another benefit that is unique when condensing DDSQ-tetrol is the formation of isomers. Ph8DDSQ(OH)4, when fully condensed with R1R2SiCl2, is the formation of conformational isomers or regioisomers. (isomers about the SQ core) The conformational isomer mixture often exhibited lower liquidus temperature than pure isomers, which benefits when mixed with organic resins at lower temperatures. Structural isomerism is the most radical type wherein the two compounds have the same number of atoms, but their chemical and physical properties are entirely different since they have logically distinct bonds. This work examines an asymmetrically capped DDSQ system synthesized as a coupling agent between graphene oxide (GO) nanofiller and styrene vinyl ester (VE) resin. The DDSQ-modified GO is dispersed into VE resin with only a simple mechanical stirring at room temperatureThis work studies the different isomers of the DDSQ system. Firstly, meta and para isomeric moieties of phenyl ethynyl phenyl (PEP) dichlorosilane were obtained via the Sonogashira reaction and by subsequent reaction with trichlorosilane. The synthesized dichlorosilanes were reacted with DDPh8T8(OH)4, and the relevant reaction conditions and yield were presented. The reaction led to the formation of cis and trans isomers. These isomers form a eutectic mixture with a sharp melting point upon varying the ratio of cis and trans products. Upon using a mixture of meta and para dichlorosilanes as capping reagents, the reaction yielded a 6-isomer mixture of compounds. This isomeric mixture didn't exhibit sharp melting characteristics as the individual isolated compounds exhibited. The sharpness of the solid-liquid transition character can also be dampened when long-chain chlorosilanes are used as capping agents for tetrol. This work also investigated the effect of constitutional isomerism in cage-like silsesquioxanes. Precisely, edge-open octaphenyl silsesquioxane diol condensed with tetramethyl dichlorosiloxane and double-decker-shaped silsesquioxane tetraol condensed with dimethyl dichlorosilanes form structural isomers. The interactions between the organic group bonded to the D-Si and the adjacent phenyl group connected to the T-Si of DDSQ molecules have a defining effect on the internal configuration of the DDSQ cage. This change affects phase transformation between liquid and solid states, forming a glassy state in a pure isolated compound
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