Coatings molecular

Schmidt RH, Mosbach K, Haupt K. A simple method for spin-coating molecularly imprinted polymer films of controlled thickness and porosity. Adv Mater 2004 16 719. 

A S321 Nitric oxide 25 ppm Draeger oxidizer, TEA TEA coated Molecular Sieve Color. 11.1-48 ppm... 

Ag-coated Chromosorb P TEA-coated molecular sieve HgCN-coated silica gel HgCl2-coated silica gel Maleic anhydride-coated Chromosorb 104... 

Phenylpropionic acid, racemic mixture /ra s-3-(3-pyridyl)acrylic acid coating molecular imprinting, 3 pm 50 mMNaH2P04, pH 4.65... 

Special systems are used to collect separately the tritiated hydrogen gas (HT) and organic-bound tritium from air. A two-component collection train consists of a molecular sieve column, followed by addition of a stream of H2 carrier gas to the sampled air before it passes through a palladium-coated molecular sieve column. The flrst column collects tritiated water and the second column collects the two other forms (Ostlund and Mason 1985). The two columns are treated separately at the laboratory, as discussed in Section 6.2.2, to provide the three forms for separate analyses. 

The other two forms of tritium gas usually are submitted on a palladium-coated molecular sieve collector. Any HT is converted to HTO by palladium-catalyzed oxidation in the collector the water is removed by heating it above its boiling point and condensing the vapor. The sorbent with the remaining organical-bound tritium is mixed with a Hopcalite catalyst and heated to 550°C to oxidize organic gases to water, which is distilled and condensed (Ostlund and Mason 1985). 

Gas chromatographic separation of hydrogen isotopes on different types of molecular sieves at the temperature of liquid nitrogen has been also investigated. Common molecular sieves 5A, 13X are not suited to this purpose. Ion-exchanged or ion-coated molecular sieves (4A, 5A, 13X) in the partially dehydrated state separate the isotopic mixtures Hg, HH, 2, and H2, HH, and H2. The resolution varied with ion content and the residual moisture content in the molecular sieves. Good separations were obtained on 15% ion-coated molecular sieve 5A and 5% ion-coated molecular sieve 4A. 

A major advance in force measurement was the development by Tabor, Win-terton and Israelachvili of a surface force apparatus (SFA) involving crossed cylinders coated with molecularly smooth cleaved mica sheets [11, 28]. A current version of an apparatus is shown in Fig. VI-4 from Ref. 29. The separation between surfaces is measured interferometrically to a precision of 0.1 nm the surfaces are driven together with piezoelectric transducers. The combination of a stiff double-cantilever spring with one of a number of measuring leaf springs provides force resolution down to 10 dyn (10 N). Since its development, several groups have used the SFA to measure the retarded and unretarded dispersion forces, electrostatic repulsions in a variety of electrolytes, structural and solvation forces (see below), and numerous studies of polymeric and biological systems. 

Small molecules can penetrate and penneate tlirough polymers. Because of this property, polymers have found widespread use in separation teclmology, protection coating, and controlled delivery [53]. The key issue in these applications is the selective penneability of the polymer, which is detennined by the diffusivity and the solubility of a given set of low-molecular-weight compounds. The diffusion of a small penetrant occurs as a series of jumps... 

Polyurethanes. About 3% of the U.S. polyurethanes market in 1988 was derived from the condensation product of polyisocyanates with low molecular weight polyadipates having hydroxyl end groups (195). In 1986 this amounted to 29,000 t, or 4% of total adipic acid consumption. The percentage was similar in Western Europe. About 90% of these adipic acid containing polyurethanes are used in flexible or semirigid foams and elastomers, with the remainder used in adhesives, coatings, and spandex fibers. 

The discovery (92) that the graphite coating of molecular sieves can dramatically improve their attrition resistance without significantly impairing adsorption performance should allow the extension of moving-bed technology to bulk gas separations (93). 

Insoluble Ammonium Polyphosphate. When ammonium phosphates are heated ia the presence of urea (qv), or by themselves under ammonia pressure, relatively water-iasoluble ammonium polyphosphate [68333-79-9] is produced (49). There are several crystal forms and the commercial products, avaUable from Monsanto, Albright WUson, or Hoechst-Celanese, differ ia molecular weight, particle size, solubUity, and surface coating. Insoluble ammonium polyphosphate consists of long chains of repeating 0P(0)(0NH units. 

Vinyl organosol coatings, which incorporate a high molecular weight thermoplastic PVC organosol dispersion resin, are extremely flexible. Soluble thermosetting resins, including epoxy, phenoHc, and polyesters, are added to enhance the film s product resistance and adhesion. 

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