Coatings thickness available

Properties Specific surface area, SEM images, FTIR spectra, XRD patterns, particle size, and coating thickness available [1905],... 

SPME has been commercially available since 1993 with various adsorbent and absor-bant materials and various coating thicknesses. Table Gl.6.1 lists some of these coatings and the types of compounds for which they are recommended. Fibers can be made in the laboratory using different polymer coatings (Be-lardi and Pawliszyn, 1989). 

Polyacrylate (PA) is a single-component polar absorbent coating commercially available in a film thickness of 85 pm [137], The sorbent is used with GC or HPLC analyses and is suitable for the extraction of polar semivolatile compounds. 

Fiber coating thickness is a second consideration in selecting a fiber for both direct immersion and headspace SPME. The PDMS coating is avail-... 

Solid-phase extraction devices and applications are evolving rapidly, and novel techniques that stretch the classical definition of SPE are becoming routine. Pawliszyn introduced solid-phase micro extraction (SPME) in 1989,5,14 and a commercial apparatus is available from Supelco (Bellefonte, PA). The SPME apparatus is merely a modified syringe that houses a fused silica optical fiber coated with an immobilized polymer film. The fiber can be exposed for extraction and then retracted for insertion or removal from the sample vial or instrument. Both manual and autosampler devices are available and each can be adjusted for proper fiber depth. Several coatings are available with varying thickness including polydimethylsiloxane, polyacrylate, polydimethylsiloxane/divinylbenzene, and carbowax/divinylben-zene. In contrast to SPE, which is an exhaustive extraction approach, SPME will extract only a fraction of an available analyte, hence it is not suitable for the isolation of impurities and degradants in most applications.15... 

Some parts might need to have a coating thickness less than what other lining processes can provide. These might include valves, tubes, pipes, and impellers. These parts may still need to be protected by a fluoropolymer coating. One of the best references is published by the Powder Coating Institute although other sources are also available. 

Powder coatings are available in FEP, PFA, MFA, ECTFE, ETFE, and PVDF. Typically, a multicoat application is required to achieve a required thickness. The powder size ranges from 1-3.54 milli-inches (25 to 90 microns). 

Zebron is a polyurethane corrosion-resistant coating material available from ACO-Coatings. It is a solvent-free product that cures in cold wet conditions and can be rapidly applied to a high film thickness in one operation. The material provides a thick abrasion and water-resistant coating to steel or concrete. 

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