Substrate encapsulation

Pentzer EB, Gadzikwa T, Nguyen ST (2008) Substrate encapsulation an efficient strategy for the RCM synthesis of unsaturated -lactones. Org Lett 10 5613-5615... 

To illustrate the current capabilities of OFET technology in this application area. Figure 2.3.2 shows an optical micrograph of an A5 active matrix display demonstrator on a flexible polyethyleneterephtalate (PET) substrate made by Plastic Logic. The display was fabricated by laminating the OFET backplane with an E Ink Imaging Film. The display has a resolution of 100 pixels per inch (ppi) and displays four levels of gray. It contains 480,000 solution-processed OFETs (600 x 800 rows and columns). No substrate encapsulation is needed. The display exhibits excellent... 

Substrate size- and shape-selective reactions can also be explained in terms of effective concentration and transition state stabilization. 1) In a mixture of substrates a higher concentration can be achieved for those having a complementary size and shape to the nanoreactor portals and cavity (and thus can enter the nanoreactor) compared to those substrates that can not easily enter or do not fit within the cavity. In some cases, when the substrate encapsulation is a slow process (slow diffusion), substrate encapsulation can become the rate-determining step. 2) One can also imagine that substrates of identical size and shape can both enter the cavity, but the transition state of one of the reaction pathways is stabilized to a greater extent than the other. Importantly, for all encapsulated reactions one should keep in mind that the substrate residence time within the nanoreactor and the kinetic rates of the encapsulated reaction should at least have a comparable magnitude. ... 

Definition Copolymer of ethylene and calcium acrylate monomers Formula (C3H4O2 C2H4)x xCa Uses Film-former processing and performance additive improves dispersion of additives in plastics adhesion to variety of substrates encapsulant for personal care prods. low m.w. ionomer flatting agent that reduces gloss in polyester powder coatings In food-pkg. adhesives... 

I. Shiyanovskaya, S. Green, G. Magyar, and J. W. Doane, Single substrate encapsulated cholesteric LCDs coatable, drapable and foldable, SID Inti Symp. Digest Tech. Papers, 36, 1556-1559 (2005). 

Enantiomeric excess (ee) as obtained by Chiral HPLC, Agilent 1200 Series -chiral column (Chiralcel OD-H) n-hexane/2 propanol/trifluoroacetic acid (100/1/0.1, v/v/v) for the Naproxen as mobile phase 24 h 20 mM of substrate Encapsulated free lipase without calixarene [44]... 

Uses Low m.w. ionomers used as processing and performance additives improves dispersion of additives in plastics adhesion to variety of substrates encapsulant for personal care prods. 

Complex Coacervation. This process occurs ia aqueous media and is used primarily to encapsulate water-iminiscible Hquids or water-iasoluble soHds (7). In the complex coacervation of gelatin with gum arabic (Eig. 2), a water-iasoluble core material is dispersed to a desired drop size ia a warm gelatin solution. After gum arabic and water are added to this emulsion, pH of the aqueous phase is typically adjusted to pH 4.0—4.5. This causes a Hquid complex coacervate of gelatin, gum arabic, and water to form. When the coacervate adsorbs on the surface of the core material, a Hquid complex coacervate film surrounds the dispersed core material thereby forming embryo microcapsules. The system is cooled, often below 10°C, ia order to gel the Hquid coacervate sheU. Glutaraldehyde is added and allowed to chemically cross-link the capsule sheU. After treatment with glutaraldehyde, the capsules are either coated onto a substrate or dried to a free-flow powder. 

As previously discussed, many, if not most, cases of particles adhering to substrates involve at least one of the contacting materials deforming plastically, rather than elastically. Under such circumstances, it would be expected that the extent of the contact should increase with time and, with it, the force needed to detach a particle from a substrate. Moreover, material flow can occur, resulting in the engulfment or encapsulation of the particles. 

The surface of the substrate, the silicone/substrate interface, and the bulk properties of silicones all play significant and influential roles that affect practical adhesion and performance of the silicone. The design of silicone adhesives, sealants, coatings, encapsulants or any products where adhesion property is needed requires the development chemist to have a thorough understanding of both silicone chemistry and adhesion phenomena. 

The surface energy of silicones, the liquid nature of the silicone polymers, the mechanical properties of the filled networks, the relative insensitivity to temperature variations from well below zero to very high, and the inherent or added reactivity towards specific substrates, are among the properties that have contributed to the success of silicone materials as adhesives, sealants, coatings, encapsulants, etc. 

Coal Slurries - Two component treatments prove to be effective on a commercial scale for coal slurry flocculation. The use of encapsulated floccuiant suspended in a counter charged floccuiant provides the robusmess of traditional dual component systems, but with additional performance advantages, which include reduction in filter cake moisture content and an increased throughput rate. Figure 5 illustrates the typical filter cake moisture content obtained by a conventional treatment system compared to the encapsulated treatment system using coal tailings as the substrate. 

Figure 9-3. Conventional multilayer light emission device (LED) indium tin oxide (ITO) electrode on a substrate, active layers A (hole transport), B (emitter), C (electron transport), and a niclat electrode. A possible encapsulation layer has been omitted, which would prevent the conjugated molecules from photo-oxidation.

Encapsulated rhodium complexes were prepared from Rh-exchanged NaY zeolite by complexation with (S)-prolinamide or M-tert-butyl-(S)-prolinamide [73,74]. Although these catalysts showed higher specific activity than their homogeneous counterparts in non-enantioselective hydrogenations, the hydrogenation of prochiral substrates, such as methyl (Z)-acetamidocinnamate [73] or ( )-2-methyl-2-pentenoic acid [74], led to low... 

Moreover, stable liquid systems made up of nanoparticles coated with a surfactant monolayer and dispersed in an apolar medium could be employed to catalyze reactions involving both apolar substrates (solubilized in the bulk solvent) and polar and amphiphilic substrates (preferentially encapsulated within the reversed micelles or located at the surfactant palisade layer) or could be used as antiwear additives for lubricants. For example, monodisperse nickel boride catalysts were prepared in water/CTAB/hexanol microemulsions and used directly as the catalysts of styrene hydrogenation [215]. 

A leuco dye(s) solution in a nonvolatile solvent is encapsulated in microcapsules 5-10 pm in diameter, and after addition of latex and wheat starch, coated (at about 5 g/m2 as dry solid) on a substrate such as paper, synthetic paper, or plastic film, and dried to give the CB sheet. 

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