Table 4 illustrates the chemical resistance properties of clear films. Solvent and acid resistance of all the filmswas good.However, the alkali resistance of ALK 1 and ALK 2 was inferior as compared to the rest of the films.
The gloss values of coating films are given in Table 4. Clear differences were observed in the tested panels. Coatings based on increased amount of DPE content not only gave the initial higher gloss but also exhibited best retention values when exposed in QUVB (_max = 313 nm) chamber for 300 and 500 h, respectively. Further, Fig. 10 shows Bode’s frequency plots for clear alkyd films of ALK 1(0% DPE), ALK 5 (50% DPE) and ALK 9 (100% DPE). ALK 9 exhibited highest value of impedance at 0.1Hz whereas ALK 1 exhibited least value of impedance. This indicates that increase in the DPE content increases the corrosion protection performance of the alkyd coating. This may be due to increased film compactness/ better gloss arising out of the branched and entangled structure of the DPE-based films.