Polyhedral oligomeric silsesquioxane

Polyhedral oligomeric silsesquioxane (POSS)-based nanocomposites... 

Nanocomposite based on polyurethane (PU) is prepared using silica, clay, and Polyhedral Oligomeric Silsesquioxane (POSS). Preparation, characterization, mechanical and barrier properties, morphology, and effect of processing conditions have been reported on polyurethane-based nanocomposites [72,73]. 

Polyhedral oligomeric silsesquioxane (POSS) has been extensively studied as starting substrate to construct nanocomposites with precise control of nanoarchitecture and properties. Octahedral derivatives are the most representative ones of this family. It was reported that the HRP-catalyzed conjugation of catechin on amine-substituted octahedral silsesquioxane amplified the beneficial physiological property of flavonoids. The POSS-catechin conjugate exhibited great... 

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... 

Controlled hydrolysis of RSiX3 compounds gives so-called silsesquioxanes or POSS compounds (Polyhedral Oligomeric SilSesquioxane), which can be used as models for silica surfaces or supports for catalysts [4] (Figure 18.2, schematic structure on the right). 

M. T. Application of ion mobility to the gas-phase conformational analysis of polyhedral oligomeric silsesquioxanes (POSS). Int J Mass Spectrom 2003, 222, 63-73. 

The proposed IR assignments were supported by calculation of v(Zr-H) frequencies of computational models for the species involved in the reactions of Scheme 3.1 [16, 17] based on a polyhedral oligomeric silsesquioxane (POSS)... 

Carroll JB, Waddon AJ, Nakade H, Rotello VM. Plug and play polymers. Thermal and X-ray characterizations of noncovalently grafted polyhedral oligomeric silsesquioxane (POSS)-polystyrene nanocomposites. Macromolecules 2003 36 6289-6291. 

Lai et al. (3) prepared reactive polyhedral oligomeric silsesquioxane derivatives,... 

Fig. 7 Examples of polyhedral oligomeric silsesquioxane (POSS) nanoparticles used to induce homeotropic alignment in nematic liquid crystals...

Pielichowski, K., Njuguna, J., Janowski, B. and Pielichowski, J. Polyhedral Oligomeric Silsesquioxanes (POSS)-Containing Nanohybrid Polymers. Vol. 201, pp. 225-296. 

Bourbigot, S., Turf, T., Bellayer, S., and Duquesne, S., 2009. Polyhedral oligomeric silsesquioxane as flame retardant for thermoplastic polyurethane. Polym. Deg. Stab. 94 1230-1237. 

FIGU RE 8.2 General structure of polyhedral oligomeric silsesquioxane. (From http //www.hybridplastics.com.)... 

Mantz, R.A., Jones, P.F., Chaffee, K.P., Lichtenhan, J.D., and Gilman, J.W., Thermolysis of polyhedral oligomeric silsesquioxane (POSS) micromers and POSS-siloxane copolymers, Chem Mater. 1996, 8, 1250. 

Fina, A., Tabuani, D., Camiato, F., Frache, A., Boccaleri, E., and Camino, G. Polyhedral oligomeric silsesquioxanes (POSS) thermal degradation, Thermochim. Acta 2006,440, 36. 

The 0-d nanoparticles can be nano-metal oxides (such as silica,1 titania,2 alumina3), nano-metal carbide,4 and polyhedral oligomeric silsesquioxanes (POSS),5 to name just a few the 1-d nanofibers can be carbon nanofiber,6 and carbon nanotubes (CNT),7 which could be single-wall CNTs (SWCNT) or multiwall CNTs (MWCNT) etc. the 2-d nano-layers include, but are not limited to, layered silicates,8 layered double hydroxides (LDH),9 layered zirconium phosphate,10 and layered titanates,11 etc. 3-d nano-networks are rarely used and thus examples are not provided here. 

Joshi, M. and Butola, B. S., Polymeric nanocomposites—polyhedral oligomeric silsesquioxanes (POSS) as hybrid nanofiller, J. Macromol. Sci., Polym. Rev. (2004), C44, 389M10. 

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