EMISSIONS OF ODOROUS ALDEHYDES FROM ALKYD PAINT

Aldehyde emissions are widely held responsible for the acrid after-odo r of drying alkyd-based paint films. The aldehyde emissions from three different alkyd paints were measured in small environmental chambers. It was found that, for each gram of alkyd paint applied, more than 2 mg of aldehydes (mainly hexanal) were emitted during the curing (dryin g) period. Since no measurable hexanal was found in the original paint , it is suspected that the aldehydes emitted were produced by autoxida tion of the unsaturated fatty acid esters in the alkyd resins. The hex anal emission rate was simulated by a model assuming that the autoxida tion process was controlled by a consecutive first-order reaction mech anism. Using the emission rate model, indoor air quality simulation in dicated that the hexanal emissions can result in prolonged (several da ys) exposure risk to occupants. The occupant exposure to aldehydes emi tted from alkyd paint also could cause sensory irritation and other he alth concerns. Published by Elsevier Science Ltd.