Standard Test Method for Laboratory Measurement of Formaldehyde Evolved During the Curing of Melamine-Formaldehyde-Based Coatings

Importancia y uso:

5.1 This test method measures the amount of formaldehyde that is evolved from a coating containing melamine-formaldehyde resin(s) during cure at elevated temperature. Cure formaldehyde results from a side-reaction during cross-linking of functionalized polymers with melamine-formaldehyde resins. Cure formaldehyde is evolved in the final bake or cure oven, when the coating temperature is high enough to initiate cross-linking. Formaldehyde can be released from a coating during application, solvent flash-off and cure. Free formaldehyde is primarily evolved during coating application and solvent flash-off. Test Method D1979 measures “free formaldehyde” in amino resins and Test Method D6191 measures formaldehyde evolved from coatings at ambient temperature. This method measures only the formaldehyde released during heat cure, which is primarily “cure formaldehyde.”

5.2 This test method is not intended to duplicate the evolved formaldehyde from an industrial process, but serves as a reproducible comparative laboratory evaluation.

5.3 This test method has not been evaluated with catalyzed coating systems that cure at or below 40 °C, such as those used by the wood-finishing industry, and would likely require special adaptation for this application.

Subcomité:

D01.21

Volúmen:

06.01

Número ICS:

83.080.10 (Thermosetting materials)

Palabras clave:

coating; cure; DNPH; formaldehyde; HPLC; melamine; VOC; volatiles;