Polystyrene nanoparticles

In the case of LASIP with clay nanoparticles, polystyrene was grafted using a DPE coinitiator. The montmorillonite clay surface and intergallery interfaces were intercalated with 1,1-diphenylethylene (DPE) modified to be an organic cation as shown in Fig. 4. Its intercalation was confirmed by a series of characterization methods including X-ray diffraction (XRD), FT-IR spectroscopy, TGA, and XPS. The results showed a complete replacement of... 

Rong Y, Chen H-Z, Wu G, Wang M (2005) Preparation and characterization of titanium dioxide nanoparticle/polystyrene composites via radical polymerization. Mater Chem Phys... 

Lui, W. (2008) New synthetic route for preparing CdS-nanoparticle/polystyrene polymer shells hybrid materials. 

FIG. 14 Measurements on monolayers and LB films of CdSe nanoparticles of narrow size distribution (a) II-A isotherms for Langmuir monolayers of CdSe nanoparticles of diameter 2.5 run (curve a), 3.0 mn (curve b), 3.6 mn (curve c), 4.3 mn (curve d), and 5.3 mn (curve e). The area per nanoparticle was determined by dividing the trough area by the estimated number of particles deposited on the surface, (b) Absorbance and photoluminescence spectra of the nanoparticles in solution (A, B) and in monolayers on sulfonated polystyrene-coated glass sbdes (C. D). The nanoparticle diameters are 2.5 nm (curves labeled a), 3.6 nm (curves labeled b), and 5.3 nm (curves labeled c). The excitation wavelengths are (a) 430 nm, (b) 490 nm, and (c) 540 nm. (Reproduced with permission from Ref. 158. Copyright 1994 American Chemical Society.)... 

Scientists also have learned how to mimic the surface of a butterfly wing. Polystyrene beads and smaller silica nanoparticles are suspended in water and mixed thoroughly using ultrasound. When a glass slide is dipped into the suspension and slowly withdrawn, a thin film forms on the glass surface. This film is a regular array of beads encased in a matrix of nanoparticles. Heating the film destroys the polystyrene beads but leaves the silica web intact. The result is a silica inverse opal film. 

A specific example where heterogeneous supports provide nanoparticle size-control is the immobilization of homogeneous silver nanoparticles on polystyrene [366]. This work was extended later to the development of a one-pot method for the size-selective precipitation of silver nanoparticles on PVP-protected thiol-functionalized silica. During the immobilization of very small silver nanoclusters both the size of the silver nanoclusters and the thickness of the silver layer on the support could be controlled directly by the reaction parameters applied (Fi re 16) [367]. 

Plastic products are known to eventually break down into smaller and smaller pieces (nanoparticles) until they are small enough to enter the cells of living organisms. Because the amount of discarded plastic is so substantial, nanoplastic particles pose an emerging environmental concern. The health effects of nanoplastics are not thoroughly understood, but polystyrene particles up to 240 nm in diameter have been proven to be transportable through placental cells [52],... 

Figure 3. Various type of SERS active metallic nanostructures (a) metal-island films (b) metal-coated nanospheres (semi-nanoshells) (c) metal-coated random nanostructures and (d) polymer coatings embedded with metal nanoparticles. Inset An SEM image of silver-coated polystyrene spheres.

Fig. 4.2 TEM images of fabricated nanoparticles, (a) Isolated composite core/shell submicron particles, (b) Hollow silica submicron particles prepared by removing the polystyrene core to demonstrate the high quality of the formed sol gel shell of the composite nanospheres employed to prepare sensing colloidal crystal films...

Partial hydrogenation of acetylenic compounds bearing a functional group such as a double bond has also been studied in relation to the preparation of important vitamins and fragrances. For example, selective hydrogenation of the triple bond of acetylenic alcohols and the double bond of olefin alcohols (linalol, isophytol) was performed with Pd colloids, as well as with bimetallic nanoparticles Pd/Au, Pd/Pt or Pd/Zn stabilized by a block copolymer (polystyrene-poly-4-vinylpyridine) (Scheme 9.8). The best activity (TOF 49.2 s 1) and selectivity (>99.5%) were obtained in toluene with Pd/Pt bimetallic catalyst due to the influence of the modifying metal [87, 88]. 

Colloidal catalysts in alkyne hydrogenation are widely used in conventional solvents, but their reactivity and high efficiency were very attractive for application in scC02. This method, which is based on colloidal catalyst dispersed in scC02, yields products of high purity at very high reactions rates. Bimetallic Pd/Au nanoparticles (Pd exclusively at the surface, while Au forms the cores) embedded in block copolymer micelles of polystyrene-block-poly-4-vinylpyridine... 

Huhtinen P, Kivela M, Soukka T, Tenhu H, Lovgren T, Harma H (2008) Preparation, characterisation and application of europium(III) chelate-dyed polystyrene-acrylic acid nanoparticle labels. Anal Chim Acta 630 211-216... 

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