Coating selection compatibility

Cellulose butyrate contains the bulkier butyryl group these esters are more compatible and soluble than acetates, but are too soft for most coating applications. Cellulose esterified with blends of alkyl groups can provide many intermediate properties needed in coatings. Selection of the appropriate cellulose acetate butyrate [9004-36-8] (CAB) and cellulose acetate propionate [9004-39-f] (CAP) content must be based on specific application requirements. 

The following guidelines illustrate the need for the paint-system approach. By considering a paint system before beginning to paint, we can be sure of selecting compatible and appropriate component coats. 

Applications of solubility parameters include selecting compatible solvents for coating resins, predicting the swelling of cured elastomers by solvents, estimating solvent vapor pressure in polymer solutions for devolatilization and reaction systems (16), and predicting phase equihhria for polymer-polymer (107), polymer-binary (93), random copolymer (102), and multicomponent solvents (38, 98,108,109). 

In the selection of lead-free solder, it is important to also select compatible board materials, board coatings, temperature-resistant components, and flux to optimize both Pb-bearing and Pb-free solder joints. As noted, there will likely be an interim time period where both Pb-containing and Pb-free components will be populated on the same PCB, depending on the cost and availability of Pb-free components. 

Porcelain enameling requires the use of frits and melting temperatures of 550 °C or below. Enamels are appHed over chemical conversion coatings that are compatible with the frit. AHoy selection is important to obtain good spall resistance. Alloys 1100, 3003, and 6061 are employed most extensively among wrought products and alloy 356 for castings. 

Tanl . Coatings for Hquid cargo tanks ate selected according to the materials that the tanks (qv) ate to contain. Tank coatings protect the cargo from contamination and must be compatible with the material carried. Epoxy systems ate most frequendy selected because they perform well with both aqueous and organic products. A carefully appHed three-coat epoxy system having a dry-film thickness of 225—300 pm can be expected to last for 12 years. 

Select mobile phases for HPSEC based on their ability to dissolve the sample and their compatibility with the column. Zorbax PSM columns are compatible with a wide variety of organic and aqueous mobile phases (Table 3.4), but analysts should avoid aqueous mobile phases with a pH greater than 8.5. As mentioned earlier, select mobile phases that minimize adsorption between samples and silica-based packings. Sample elution from the column after the permeation volume indicates that adsorption has occurred. If adsorption is observed or suspected, select a mobile phase that will be more strongly adsorbed onto the silica surface than the sample. For example, N,N-dimethyl-formamide (DMF) is often used for polyurethanes and polyacrylonitrile because it eliminates adsorption and dissolves the polymers. When aqueous mobile phases are required, highly polar macromolecules such as Carbowax can be used to coat the silica surface and eliminate adsorption. Table 3.5 provides a list of recommended mobile-phase conditions for some common polymers. 

Microbiocides may be toxic to humans therefore, care must be taken when used. When selecting the microbiocide, the field engineer can obtain pertinent information on chemicals from the service company providing the chemicals. The microbiocide selected must be compatible with the system in which it is being used. Some chemicals such as quaternary amines have dual functions one as microbiocides and the other as film-forming corrosion inhibitors. Insufficient concentrations of this type of chemical may not be enough to coat the whole surface of metal and can cause pitting corrosion. The selection must also depend on chemicals that can produce the desired control in minimum time limits and... 

Graphite composites Polished Wide solvent compatability, increased signal/background current, easy chemical modification Binder can coat carbon Selectivity can be varied with chemical modification 3... 

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