Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
693019 | Progress in Organic Coatings | 2012 | 10 Pages |
Abstract
Properties of coatings based on alkyd resin can be improved via blending with other suitable resins. Recent studies assessed that many properties could be improved by blending with epoxy resins as well as with melamine resins. The aim of this work was to investigate the effect of epoxy resin content on the curing process in alkyd-melamine-epoxy three component blends. The coatings with two mixing ratios of alkyd/melamine (70:30 and 80:20) were formulated. They were made into baking enamels by blending with 3 and 5Â wt% of epoxy resin on total resin solid. Curring kinetics was investigated by differential scanning calorimetry (DSC) and application of Ozawa isoconversional method. Fourier transform infrared spectroscopy (FTIR) was used to follow major curing reactions. The absorbance of -OH and -N-CH2R, showed significant reduction and confirmed that the epoxy resin reacts and inserts in enamel structure. It was found that resin system with alkyd/melamine ratio of 70:30 and 3Â wt% of epoxy resin has the lowest apparent activation energy of 141.5Â kJÂ molâ1 and needs the shortest time of 34.2Â min to reach final apparent degree of cure. Isothermal DSC experiments have confirmed these findings. The samples with 30Â wt% of melamine resin had higher hardness of baked enamels then samples with 20Â wt%. They also showed an increase of hardness with the increase of epoxy resin content.
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Physical Sciences and Engineering
Chemical Engineering
Process Chemistry and Technology
Authors
Suzana M. CakiÄ, Ivan S. RistiÄ, Vladislav M. JaÅ¡o, Radmila Ž. RadiÄeviÄ, Olivera Z. IliÄ, Jaroslava K.B. SimendiÄ,