Powder coatings chemistry

T. E. Misev, Powder Coatings, Chemistry and Techno/ogy,]ohxi Wiley Sons, Inc, New York, 1991. 

Misev T (1991) Powder coatings, chemistry and technology. Wiley, New York... 

The example is based on T. A. Misev Powder Coatings, Chemistry and Technology, Wiley 1991. 

Mazumder, M. K., E-SPART Analyzer Its Performance and Application to Powder and Particle Technology Processes, KONA, No. 11, 1993, pp. 105-118. Mazumder, M. K., R. E. Ware, T. Yokoyama, B. J. Rubin, and D. Kamp, Measurement of Particle Size and Electrostatic Charge Distributions on Toners Using E-SPART Analyzer, IEEE Trans. Ind. Appl., 27, 1991, pp. 611-619. McLean, K. J., Cohesion of Precipitated Dust Layer in Electrostatic Precipitators, J. Air Pol. Contrl. Assoc., 27, 11, Nov. 1977, pp. 1100-1103. Misev, T. A., Powder Coatings, Chemistry and Technology, Wiley, NY, 1991, p. 292. 

Solvent absorption measurement has been shown to be a sensitive and useful test method in the manufacture of epoxy powder coatings. A test method was defined and the effects of time and temperature of immersion described. It was shown that solvent absorption is a measure of raw material properties (EEW of the epoxy resin, and CTBN elastomer type and concentration), the homogeneity of the extrudate, as well as the state of cure. The information obtained from solvent absorption measurements has proven to be extremely important not only in quality control analysis but also in providing an insight into the structure function relationships in epoxy resin chemistry. 

The Chemistry of UV-Curable Powders Material and Substrate Preparation Powder Coating Application Substrates Suitable for UV Powder Coating... 

To be suitable for radiation-curable powder coatings, materials must contain unsaturated double bonds. They may contain acrylic or methacrylic unsaturations, but nonacrylate systems can also be used.32 The latter are based on the same chemistry... 

We have shown how the band structure of photoexcited semiconductor particles makes them effective oxidation catalysts. Because of the heterogeneous nature of the photoactivation, selective chemistry can ensue from preferential adsorption, from directed reactivity between adsorbed reactive intermediates, and from the restriction of ECE processes to one electron routes. The extension of these experiments to catalyze chemical reductions and to address heterogeneous redox reactions of biologically important molecules should be straightforward. In fact, the use of surface-modified powders coated with chiral polymers has recently been reputed to cause asymmetric induction at prochiral redox centers. As more semiconductor powders become routinely available, the importance of these photocatalysts to organic chemistry is bound to increase. 

The types of powder coatings available are gradually evolving with the advent of new powder chemistries that allow for numerous formulation variations. For example, powder coatings have been developed to replace porcelain in laundry applications, heat-resistant polymers for range door trim, and flexible powder coatings for refrigerator doors. This wide latitude in formulation capabilities means that there may be more than one resin chemistry used in a particular powder formulation. 

The generation of a convenient processing window is difficult for most known crosslinking chemistries. This has limited the use of powder coatings at temperatures lower than about 130 °C, a fact that precludes their use on many plastic substrates. Efforts to develop radiation-curable powder coatings are ongoing. 

D. A. Bate, The Science of Powder Coatings, Vol. 1 Chemistry Formulation and Application, Sita Technology Ltd., London, 1990. 

The chemistry of bismuth vanadate pigments makes them sensitive to acids. Ho v-ever, tests in which acids were applied to baking finishes under practical conditions have shown that the acid resistance of these pigments is normally comparable to that of a highly stabilized lead chromate. The application of bismuth vanadate pigments in powder coatings and coil-coatings should be tested in customer material, because in such cases - more than in standard liquid paint systems - the suitability depends on the total formulation. 

Michalski, J., Konopka, K. and Trszaska, M. (2003) Description of AI2O3 powders coated hy Ni-P particles obtained through an electroless chemical reaction and possibilities to obtain an Al203/Ni-P composite. Materials Chemistry and Physics, 81, 407-410. 

R Ryntz, M Everson, G PoUano. Friction induced paint damage as affected by clearcoat chemistry. Proceedings of Twenty-Fourth International Waterborne, High-Solid, and Powder Coatings Symposium, New Orleans, 1997, pp 259-276. 

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