Deposition vapor-phase

J. B. MacChesney, P. B. O Connor, P. V. DiMarceUo, J. R. Simpson, and P. D. La2ay, "Preparation of Low-Loss Optical Pibers Using Simultaneous Vapor-Phase Deposition and Pusion," in Proceedings of t/je Tent/j Internationa/ Congress on G/ass, Ffoto, Japan, Vol. 6 Ceramics Society, Japan, 1974, pp. 50—54. 

Fig. 21. Schematic illustration of the four primary vapor-phase deposition processes used in optical-fiber fabrication outside vapor deposition (OVD), modified chemical vapor deposition (MCVD), plasma vapor deposition (PVD), and vapor axial deposition (VAD) (115).

Another important function of metallic coatings is to provide wear resistance. Hard chromium, electroless nickel, composites of nickel and diamond, or diffusion or vapor-phase deposits of sUicon carbide [409-21-2], SiC , SiC tungsten carbide [56780-56-4], WC and boron carbide [12069-32-8], B4C, are examples. Chemical resistance at high temperatures is provided by aUoys of aluminum and platinum [7440-06-4] or other precious metals (10—14). 

Fluoroall l-SubstitutedTitanates. Tetraliexafluoroisopropyl titanate [21416-30-8] can be prepared by the reaction of TiCl and hexafluoroisopropyl alcohol [920-66-17, in a process similar to that used for TYZOR TPT (7). Alternatively, it can be prepared by the reaction of sodium hexafluoroisopropoxide and TiCl ia excess hexafluoroisopropyl alcohol (8). The fluoroalkyl material is much more volatile than its hydrocarbon counterpart, TYZOR TPT, and is used to deposit titanium on surfaces by chemical vapor-phase deposition (CVD). 

In fact, the 4- or 3-aminophthalic anhydride (4-APA and 3-APA) gives only intractable oligomers as pointed out later.154 Interesting are the attempts of vapor-phase deposition of 4-APA, 3-APA, and 4-amino naphtlialic anhydride (4-ANA). The sublimation of 3-APA gives only a low yield of polyimide. With both 4-APA and 4-AN A no sublimation took place and oligomeric products were formed before melting.154... 

Polylactides, 18 Poly lactones, 18, 43 Poly(L-lactic acid) (PLLA), 22, 41, 42 preparation of, 99-100 Polymer age, 1 Polymer architecture, 6-9 Polymer chains, nonmesogenic units in, 52 Polymer Chemistry (Stevens), 5 Polymeric chiral catalysts, 473-474 Polymeric materials, history of, 1-2 Polymeric MDI (PMDI), 201, 210, 238 Polymerizations. See also Copolymerization Depolymerization Polyesterification Polymers Prepolymerization Repolymerization Ring-opening polymerization Solid-state polymerization Solution polymerization Solvent-free polymerization Step-grown polymerization processes Vapor-phase deposition polymerization acid chloride, 155-157 ADMET, 4, 10, 431-461 anionic, 149, 174, 177-178 batch, 167 bulk, 166, 331 chain-growth, 4 continuous, 167, 548 coupling, 467 Friedel-Crafts, 332-334 Hoechst, 548 hydrolytic, 150-153 influence of water content on, 151-152, 154... 

Vapor-phase deposition polymerization polyimide synthesis by, 303 PQ and PPQ synthesis by, 312... 

Figure 16.3 Vapor phase deposition of molecules and gradients of coverage of molecules formed on a surface.

It is therefore unnecessary to alter the chemical properties of the bulk material, e.g. by using vapor phase deposition of sensitizer and monomer. This can be seen by comparison of ATR-IR and ESCA spectra of grafted PP surfaces (Figure 3). 

Thin Films from Vapor-phase Deposition Techniques 1008... 

MA Baldo, M Deutsch, PE Burrows, H Gossenberger, M Gerstenberg, V Ban, and SR Forrest, Organic vapor phase deposition, Adv. Mater., 10 1505-1514, 1998. 

Compares ink jet printing and vapor phase deposition technologies for thin films preparation... 

Metastable vapor-phase deposition, of synthetic diamond, 8 538-539 Metastasis, 25 205... 

Tungdten(or Wolfram) Hexafluoride, WFfl, mw 297.86 colorless gas or It yel liquid toxic sp gr(liq) 3.44, fr p 2.5°, bp 19 5°. Can be prepd by direct fluorinarion of powdered tungsten, followed by distillation under pressure. Used for vapor phase deposition of tungsten and as fluorinaring agent Refs 1) Gmelin-Kraut Syst Number 54(1933), 155 2) Lange (1961), 32 4 3) CondChem-... 

Vapor-phase deposition of the sputtered or evaporated layer-forming material avoids the undercooling problems associated with liquid phase epitaxy, but it coats everything in the vaporization chamber unselectively. Sputtering is usually done by forming a plasma (ionized gas) in an electrical discharge in the vapor at low pressure. 

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