The colorants are strongly fluorescing and long lasting with excellent light stability. The novel colorants can be prepared from chromophores found in common pigments and provide a simple way to convert an insoluble pigment into a soluble fluorescent colorant. The present invention provides novel fluorescent polyhedral oligomeric silsesquioxane POSS colorants. The colorants are strongly fluorescing and long lasting and are useful in a wide variety of applications including printing inks, coatings and the coloration of plastics.
Save A cubic silsesquioxane. Silsesquioxanes are members of polyoctahedral silsesquioxanes "POSS"which have attracted attention as precursors to ceramic materials and nanocomposites. Diverse substituents R can be attached to the Si centers.
The molecules are unusual because they feature an inorganic silicate core and an organic exterior. The silica core confers rigidity and thermal stability.
Structure Silsesquioxanes are known in molecular form with 6, 8, 10, and 12 Si vertices, as well as polymers. In all cases each Si center is bonded to three oxo groups, which in turn connect to other Si centers. The fourth group on Si is usually an alkyl, halide, hydride, alkoxide, etc.
The O-Si-O angle are in the range: Consequently, silsesquioxanes can be obtained directly by condensation of the corresponding silanetriols which occurs at neutral pH and works even for sterically very bulky substituents. Bridged polysilsesquioxanes are most readily prepared from clusters that contain two or more trifunctional silyl groups attached to non-hydrolysable silicon-carbon bonds, with typical sol-gel processing.
Such an inversion is observed at silicon atom during nucleophilic displacement reaction that is usually noticed when leaving groups are replaced by soft nucleophiles.
Because this reaction takes place in an aqueous conditions, compound E of general formula T OH as a consequence of hydrolysis reaction was obtained. Although, heptahedral F is less favorable energetically MM2 datain this case its creation is forces by the formation of a new SiO moiety from much more less stable substrates D and E.
Poly phenylsilsesquioxane does not adopt a cage structure, but is a polymer with a ladder-like repeating unit. Polymeric silsesquioxanes Polymeric silsesquioxanes have been reported, first by Brown. High molecular weight tractable polymeric phenyl silsesquioxane featured a ladder-type structure.
Brown's synthesis proceeded in three-steps: Other notable silsesquioxane polymers include the soluble polymethylsilsesquioxane with high molecular weights described by Japan Synthetic Rubber. The T cluster was also synthesized by the reaction of trimethylsilane with a mixture of acetic acid, cyclohexane, and hydrochloric acid.
The Si-H groups are amenable to hydrosilylation. Bridged silsesquioxanes have been used for quantum confined nano-size semiconductors. Silsesquioxane resins have also been used for these applications because they have high dielectric strengths, low dielectric constants, high volume resistivities, and low dissipation factors, making them very suitable for electronics applications.
These resins have heat and fire resistant properties, which can be used to make fiber-reinforced composites for electrical laminates.
Polyhedral oligomeric silsesquioxanes have been examined as a means to give improved mechanical properties and stability, with an organic matrix for good optical and electrical properties. Hydridosilsesquioxanes can be converted to silica coatings for potential application in integrated circuits.Polyhedral oligomeric silsesquioxanes, now commonly referred to under the trade name POSS, were discovered in the s.
Although they were not pursued commercially at that time, there was a revival of interest in the s and that interest has been sustained globally ever since. SILICON-CONTAINING POLYMERS AND COMPOSITES OMNI HOTEL, SAN DIEGO, CALIFORNIA USA * DECEMBER , SILICON-CONTAINING POLYMERS AND COMPOSITES OMNI HOTEL, SAN DIEGO, CALIFORNIA USA * DECEMBER , Lecture Polyhedral Oligomeric Silsesquioxane (Fluoro-POSS) and a Fluoroelastomer.
May 01, · Sample records for ladder logic diagrams (GIG) and capabilities and potential breakthroughs. The GIG is comprised of 7 million devices spread across 15, networks that are attacked “hundreds of. The we find that the effective field theory describing the system is a self-dual sine-Gordon model, which favors ordering and the.
silsesquioxane molecules General structure of silsesquioxane-based BoC oligomers Model compounds of silsesquioxane-based BoC oligomers with –Si(OEt) 3 endcaps.
A silsesquioxane is an organosilicon compound with the chemical formula [RSiO] (R = H, alkyl, aryl or alkoxyl).  Silsesquioxanes are colorless solids that adopt cage-like or polymeric structures with Si-O-Si linkages and tetrahedral Si vertices.
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