Poly silsesquioxane

Bian, Y., Pejanovic, S., Kenny, J., Mijovic, J. Dynamics of multifunctional polyhedral oligomeric silsesquioxane/poly(propylene oxide) nanocomposites as studied by dielectric relaxation spectroscopy and d5mamic mechanical spectroscopy. Macromolecules 40 (2007) Boucher, V.M., Cangialosi, D., Alegria, A., Colmenero, J. Time dependence of the segmental relaxation time of poly(vinyl acetate)-silica nanocomposites. Phys. Rev. E 86, 041501 (2012)... 

POLY(SILOXANES), POLY(SILSESQUIOXANES), POLY(SILMETHYLENES) ... 

Poly(chlorophenyl silsesquioxane) Poly(chlomphenyl siloxane)... 

PDMS nanocomposites with layered mica-type silicates were also reported.374 A two-step sol-gel process of the in situ precipitation of silica led to the development of siloxane-based nanocomposites with particularly high transparencies.3 5 Some unusual nanocomposites prepared by threading polymer chains through zeolites, mesoporous silica, or silica nanotubes were reviewed.3 6 Poly(4-vinylpyridine) nanocross-linked by octa(propylglycidyl ether) polyhedral oligomeric silsesquioxane was reported.377... 

On the other hand, silicones are used in organic composites. The application of alloys composed of the fully cured silicone rubber particles in a continuous thermoplastic phase, called thermoplastic silicone vulcanizate, which offers high-performance materials, has been reported.506,507 Functionalized POSS was not only co-polymerized, but also blended with poly(methylmethacrylate) to study the effect of silsesquioxanes on the thermal stability of thermoplastics.508... 

Among several families of compounds used as molecular models for such surface silanolic grafting sites (mono or poly-silanols [10-12], heteropolyanions [13, 14], calixarenes [15, 16], tripodal amido complexes [17], etc.) some silsesquioxanes [18-23] can be considered among the most convincing molecular analogues of silica surface silanols. 

A polyhedron silsesquioxane ladder polymer containing polymerizable components was prepared in a three-step process to address this concern. The process initially entailed preparing the reversible addition-fragmentation transfer (RAFT) ladder iniferter, polysilsesquioxane dithiocarbamate. This intermediate was then polymerized with methyl methacrylate at ambient temperature by irradiating with ultraviolet (UV) light and poly(si Isesquioxane-g-methyl methacrylate) was obtained. 

To obtain resin, the hot product of condensation is poured through the lower drain of condenser 18 to obtain varnish, the resin in condenser 18 is dissolved with ethyl alcohol, which self-flows into the apparatus from batch box 21. While the resin is dissolved, cooler 19 operates in the inverse mode. The obtained varnish is loaded by vacuum into settling box 22, where it is settled at ambient temperature for a long time (24-48 hours) to separate mechanical impurities. There is also a possibility for additional centrifuging in ultracentrifuge 23 for complete elimination of mechanical impurities, as well as clarification" of the varnish. The finished poly-methyl(phenyl)silsesquioxane varnish is sent from the centrifuge into container 24 and packaged. 

Tsai MH, Whang WT (2002) Low Dielectric Polyimide/Poly(silsesquioxane)-Like Nanocomposite Material, Polymer 42(9) 4197—4207... 

The PDMAEMA stars are weak cationic polyelectrolytes. But they can be easily transformed into strong cationic polyelectrolytes poly [2-(methacryloyloxy)ethyl] trimethylammonium iodide] (PMETAI) stars by quaternization with methyl iodide. Asymmetric field flow fractionation (AFFF) measurements showed that the silsesquioxane core remained intact. The PMETAI brushes were also subjected to... 

RELATED POLYMERS Polyalkylsilsesquioxane and poly-co-silsesquioxanes. There are many references to these classes of materials,but they are generally jxxjrly characterized. Thus, they are not included in this handbook. 

POSS, polyhedral oligomeric silsesquioxane PCU, polycarbonate urethane PU, polyurethane PEU, poly(aher urethanes) PTFE, polytetrafluoroethylene PVA, polyvinyl ... 

Kessler D, Theato P (2008) Synthesis of functional inorganic-organic hybrid polymers based on poly(silsesquioxanes) and their thin film properties. Macromolecules 41 5237-5244... 

Kessler D, Lowe H, Theato P (2009) Synthesis of defined poly(silsesquioxane)s fast poly-condcaisation of trialkoxysilanes in a etmtinuous-flow microreactor. Macnnnol Chem Phys 210 807-813... 

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