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Nanocomposites silica

FIGURE 3.28 Static holding power test results of acrylic terpolymer-silica nanocomposite adhesives carried out on Al, W, and PP substrates. (From Patel, S., Bandyopadhyay, A., Ganguly, A., and Bhowmick, A.K., J. Adhes. Sci. TechnoL, 20, 371, 2006. Courtesy of VSP-Brill Academic Publishers.)... [Pg.83]

Table 7. As can be seen, both Dowex and Deloxan led to poor enantioselec-tivities, which further decreased after catalyst recovery. Better results, which are comparable with those obtained in homogeneous phase, were obtained with Nation (Table 7) [53], although it was necessary to carry out the reaction at 60 °C due to the low copper content in the soHd. This low copper level is a consequence of the low surface area of this polymer (< 0.02 m g ) and, for this reason, a nafion-silica nanocomposite was used as the support [53]. With this catalyst, the reaction took place at room temperature and with similar enantioselectivity (Table 7). Table 7. As can be seen, both Dowex and Deloxan led to poor enantioselec-tivities, which further decreased after catalyst recovery. Better results, which are comparable with those obtained in homogeneous phase, were obtained with Nation (Table 7) [53], although it was necessary to carry out the reaction at 60 °C due to the low copper content in the soHd. This low copper level is a consequence of the low surface area of this polymer (< 0.02 m g ) and, for this reason, a nafion-silica nanocomposite was used as the support [53]. With this catalyst, the reaction took place at room temperature and with similar enantioselectivity (Table 7).
Laufer MC, Hausmann H, Holderich WF (2003) Synthesis of 7-hydroxycoumarins by Pechmann reaction using Nation resin/silica nanocomposites as catalysts. J Catal 218 315-320... [Pg.183]

Entrapment of Biopolymers into Sol-Gel-derived Silica Nanocomposites... [Pg.75]

It did not give rise to phase separation or precipitation. Similar behavior was observed when other types of polysaccharides were examined [53,54]. By now all the commercially important polysaccharides have been applied to the fabrication of hybrid silica nanocomposites in accordance with Scheme 3.2. What is more, various proteins have been entrapped in silica by the same means. In all instances the THEOS demonstrated good biocompatibility with biopolymers, even though its amount in formulations was sometimes up to 60 wt%. Biopolymer solutions after the precursor admixing remained homogeneous to the point of transition into a gel state. [Pg.89]

Tab. 3.1 Polysaccharides and proteins involved in the synthesis of hybrid silica nanocomposite materials. Tab. 3.1 Polysaccharides and proteins involved in the synthesis of hybrid silica nanocomposite materials.
A set of articles devoted to hybrid protein-silica nanocomposites has been prepared for publication. [Pg.102]

Applications of sol-gel-processed interphase catalysts. Chemical Reviews, 102, 3543-3578. Pierre, A.C. (2004) The sol-gel encapsulation of enzymes. Biocatalysis and Biotransformation, 22, 145-170. Shchipunov, Yu.A. (2003) Sol-gel derived biomaterials of silica and carrageenans. Journal of Colloid and Interface Science, 268, 68-76. Shchipunov Yu.A. and Karpenko T.Yu. (2004) Hybrid polysaccharide-silica nanocomposites prepared by the sol-gel technique. Langmuir, 20, 3882-3887. [Pg.105]

Shchipunov, Yu.A., Karpenko, T.Yu., Bakunina, I.Yu., Burtseva, Yu.V. and Zvyagintseva, T.N. (2004) A new precursor for the immobilization of enzymes inside sol-gel derived hybrid silica nanocomposites containing polysaccharides. Journal of Biochemical and Biophysical Methods, 58, 25-38. [Pg.106]

First attempts to incorporate pre-formed magnetite colloids within alginate/silica nanocomposites via a spray-drying process have been described, but formation of lepidocrocite y-FeOOH and fayalite Fe2Si04 was observed, attributed to Fe2+ release during the aerosol thermal treatment [53],... [Pg.168]

Coradin, T., Allouche, J., Boissiere, M. and Livage, J. (2006) Sol-Gel biopolymer/silica nanocomposites in biotechnology. Current Nanoscience, 2, 219-230. [Pg.186]

Rhee, S. and Choi J. (2002) Preparation of a bioactive poly(methyl methacrylate) /silica nanocomposite. Journal of the American Ceramic Society, 85, 1318-1320. [Pg.397]

Rhee, S.H. (2003) Effect of calcium salt content in the poly(e-caprolactone)/ silica nanocomposite on the nudeation and growth behavior of apatite layer. Journal of Biomedical Materials Research, 67A,1131-1138. [Pg.398]

Yoo, J.J. and Rhee S.H. (2004) Evaluations of bioactivity and mechanical properties of poly (e-caprolactone) silica nanocomposite following heat treatment. Journal of... [Pg.398]

Hybrid polymer silica nanocomposites formed from various combinations of silicon alkoxides and polymers to create a nanoscale admixture of silica and organic polymers constitute a class of composite materials with combined properties of polymers and ceramics. They are finding increasing applications in protective coatings (Figure 7.1), optical devices, photonics, sensors and catalysis.1... [Pg.160]

Gas permeation properties of ethylene vinyl acetate-silica nanocomposite membranes./. Membr. Sd., 322 (2), 423 28. [Pg.350]

Although the bulk of PDA sensors involve vesicles and Langmuir monolayers, a few examples of responsive PDA assemblies based on bolaamphiphiles and diyne silica nanocomposites have been reported (Lu et al. 2001 Song et al. 2001, 2004 Yang et al. 2003 Peng et al. 2006). Although these materials have not been broadly utilized for analyte sensing, they do exhibit the thermochromic, solvatochro-mic, and pH responsive behavior seen with monolayers and liposomes and hold promise for future development. [Pg.323]

Lu Y, Yang Y, Sellinger A, Lu M, Huang J, Pan H, Haddad R, Lopez G, Bums AR, Sasaki DY, Shelnutt J, Brinker CJ. Self-assembly of mesoscopically ordered chromatic polydiacety-lene/silica nanocomposites. Nature 2001 410 913-917. [Pg.331]


See other pages where Nanocomposites silica is mentioned: [Pg.253]    [Pg.68]    [Pg.81]    [Pg.83]    [Pg.85]    [Pg.130]    [Pg.126]    [Pg.4]    [Pg.5]    [Pg.6]    [Pg.98]    [Pg.99]   
See also in sourсe #XX -- [ Pg.75 , Pg.89 ]

See also in sourсe #XX -- [ Pg.61 , Pg.62 , Pg.63 , Pg.64 , Pg.65 ]

See also in sourсe #XX -- [ Pg.317 ]




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