Surface modifier

Clearly, it is important that there be a large contact angle at the solid particle-solution-air interface. Some minerals, such as graphite and sulfur, are naturally hydrophobic, but even with these it has been advantageous to add materials to the system that will adsorb to give a hydrophobic film on the solid surface. (Effects can be complicated—sulfur notability oscillates with the number of preadsoibed monolayers of hydrocarbons such as n-heptane [76].) The use of surface modifiers or collectors is, of course, essential in the case of naturally hydrophilic minerals such as silica. 

Materials that typify thermoresponsive behavior are polyethylene—poly (ethylene glycol) copolymers that are used to functionalize the surfaces of polyethylene films (smart surfaces) (20). When the copolymer is immersed in water, the poly(ethylene glycol) functionaUties at the surfaces have solvation behavior similar to poly(ethylene glycol) itself. The abiUty to design a smart surface in these cases is based on the observed behavior of inverse temperature-dependent solubiUty of poly(alkene oxide)s in water. The behavior is used to produce surface-modified polymers that reversibly change their hydrophilicity and solvation with changes in temperatures. Similar behaviors have been observed as a function of changes in pH (21—24). 

B. D. Bauman, "Novel Polyurethane Composites with Surface-Modified Polymer Particles," paper presented at SPI 32nddnnual Technical Marketing Conference, 1989. 

The white cell adsorption filter layer is typically of a nonwoven fiber design. The biomaterials of the fiber media are surface modified to obtain an optimal avidity and selectivity for the different blood cells. Materials used include polyesters, eg, poly(ethylene terephthalate) and poly(butylene terephthalate), cellulose acetate, methacrylate, polyamides, and polyacrylonitrile. Filter materials are not cell specific and do not provide for specific filtration of lymphocytes out of the blood product rather than all leukocytes. 

D. M. Parkin, in C. J. McHargue, R. Kossowsky, and W. O. Hofer, eds.. Structure—Property Relationships in Surface-Modified Ceramics Kluwer Academic Publishers, Dordrecht, 1989, p. 47. 

T. Hioki and co-workers, ia C. McHargue and co-workers, eds.. Structural—Property Relationships in Surface Modified Ceramics, Kluwer Academic Pubhshers, Dordrecht, the Netherlands, 1989, p. 303. 

Infiltration (67) provides a unique means of fabricating ceramic composites. A ceramic compact is partially sintered to produce a porous body that is subsequently infiltrated with a low viscosity ceramic precursor solution. Advanced ceramic matrix composites such as alumina dispersed in zirconia [1314-23-4] Zr02, can be fabricated using this technique. Complete infiltration produces a homogeneous composite partial infiltration produces a surface modified ceramic composite. 

A good example of a surface-modified lens is the Sola/Bames-Hind Hydrocurve Flite lens, introduced in 1986. The material for the commercial Hydrocurve lens, bufilcon A [56030-52-5] contains methacrylic acid and has a high affinity for protein and subsequent deposition. The surface of the Flite lens was chemically modified with the addition of diazomethane (190) to reduce the surface charge. In vitro testing demonstrated a decrease in protein adsorption (191). 

Infrared spectroscopy, including Fourier-transform infrared (FTIR) spectroscopy, is one of the oldest techniques used for surface analysis. ATR has been used for many years to probe the surface composition of polymers that have been surface-modified by an etching process or by deposition of a film. RAIR has been widely used to characterize thin films on the surfaces of specular reflecting substrates. FTIR has numerous characteristics that make it an appropriate technique for... 

Cyanoacrylate adhesives cure by anionic polymerization. This reaction is catalyzed by weak bases (such as water), so the adhesives are generally stabilized by the inclusion of a weak acid in the formulation. While adhesion of cyanoacrylates to bare metals and many polymers is excellent, bonding to polyolefins requires a surface modifying primer. Solutions of chlorinated polyolefin oligomers, fran-sition metal complexes, and organic bases such as tertiary amines can greatly enhance cyanoacrylate adhesion to these surfaces [72]. The solvent is a critical component of these primers, as solvent swelling of the surface facilitates inter-... 

Deruelle, M., Tirrell, M., Marciano, Y., Hervet, H. and Leger, L, Adhesion energy between polymer networks and solid surfaces modified by polymer attachment. Faraday Discuss., 98, 55-65 (1995). 

Fig. 1 Schematic view of the surface-modified silica gels at present commercially available.

Fig. 6-15. Synthetic scheme of surface-modified MIP for (5)-naproxen. V65 = 2,2 -azobis(2,4-dimethylvaleronitrile) GMMA = glycerolmonomethacrylate GDMA = glyceroldimethacrylate.

The dendritic growth of lithium was suppressed on a lithium electrode surface modified by an ultrathin solid polymer electrolyte prepared from 1,1—difluoro-ethane by plasma polymerization [114]. 

Both Swinkels et al. [7] and Chabre and Pannetier [9] described the process of EMD reduction as three overlapping processes. Recently Donne et al. reported [9] that the presence of Bi (OH)3 on the EMD surface modified the discharge curve considerably and the rechargeability was increased. Formation of the bimessite structure from EMD and Bi (OH), or Bi203 (mechanically mixed with EMD) [11] is the cause of the increase in rechargeability. 

Solar energy, 6, 488 surface modified electrodes, 6, 30 Sol-Gel process fast reactor fuel, 6, 924 Solid state reactions, 1, 463-471 fraction of reaction, 1, 464 geometric, 1, 464 growth, 1, 464 nucleation, 1, 464 rate laws, 1,464 Solochrome black T metallochromic indicators, 1,555 Solubility... 

ADSORPTION ON SURFACES MODIFIED BY ELECTROPOSITIVE OR ELECTRONEGATIVE PROMOTERS... 

Adsorption of Gases on Surfaces Modified by Alkali Promoters... 

CATALYTIC ACTIVITY ON SURFACES MODIFIED BY PROMOTERS OR POISONS... 

K. Asakura, J. Lanterbach, H.H. Rothermund, and G. Ertl, Spatio-temporal pattern formation during catalytic CO oxidation on a Pt(100) surface modified with submonolayers of Au, Surf. Sci. 374, 125-141 (1997). 

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