Powder coating fluidized bed

Typical processing methods compression molding, electrostatic powder coating, fluidized bed coating, film/tube extrusion, flame and plasma spraying, injection molding monofilament extrusion, wire cable injection molding ... 

They can be processed by techniques commonly used for thermoplastics, such as extrusion, injection molding, rotational molding, dip, slush molding, and powder and fluidized bed coating,16 and can be expanded into foams.17 Compression and transfer molding of FEP resins can be done, but with some difficulty. Extrusion of PEP is used for primary insulation or cable jackets and for tubing and films. 

Ichikawa, H. Tokumitsu, H. Jono, K. Osako, Y. Fukumori, Y. Coating of pharmaceutical powders by fluidized bed process. VI. Microencapsulation using blend and composite latices of copoly(ethyl acrylate-methyl methacryalte-2-hydroxyethyl methacrylate). Chem. Pharm. Bull. 1994, 42 (6), 1308-1314. 

The volume of thermosetting powders sold exceeds that of thermoplastics by a wide margin. Thermoplastic resins are almost synonymous with fluidized-bed appHed thick-film functional coatings whereas thermosetting powders are used almost exclusively in electrostatic spray processes and appHed as thin-film decorative coatings. 

Almost all PVC powder coatings are appHed by the fluidized-bed coating process. Although some electrostatic spray-grade formulations are available, they are very erratic in their appHcation characteristics. The resistivity of plasticized PVC powders is low compared to other powder coating materials and the appHed powder quickly loses its electrostatic charge. For the same reason, PVC powders show poor appHcation characteristics in an electrostatic fluidized bed and are seldom used in this process. 

Nylon coating powders are available for electrostatic spray and fluidized-bed appHcation. Nylon coatings are very tough, resistant to scratching and... 

Most plastics are now available as powders and can be applied as coatings by fluidized bed or spraying techniques. Nylon 11 and polyethylene have proved most useful for chemical plant applications. 

Powder epoxies Applied as powder either by electrostatic gun or fluidized bed, these materials must be cured at 200-250°C. The coating cures within a few seconds and is normally water quenched to control cure time. They have good resistance to water but will tend to chalk on outdoor exposure. 

Powder coating is a solventless coating system that is not dependent upon a sacrificial medium such as a solvent, but is based on the performance constituents of solid TP or TS plastics. It can be a homogeneous blend of the plastic with fillers and additives in the form of a dry, fine-particle-size compound similar to flour. The three basic methods are the fluidized bed, electrostatic spray, and electrostatic fluidized bed processes (9). 

To protect steel piping and wire we can powder coat it with a layer of nylon 11. The powder coating process consists of immersing metal heated to above the melting point of nylon II (approximately 190 °C) in a fluidized bed of the polymer powder. When the polymer powder comes into contact with the heated metal, it melts and fuses to form a continuous coating. Powder coated products include hospital bed frames, shopping trolleys, and dishwasher racks. 

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