UV-curing of coatings based on black seed oil modified epoxy resin

UV-curing of the coatings based on epoxy resin modified by black seed oil (EBSO); 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane carboxylate - a biscycloaliphatic diepoxide (BCDE) and photoinitiator triarylsulfonium hexafluoroantimonate salts (TAS) with various EBSO/BCDE weight ratios have been investigated. The variation of TAS and functional groups in the coatings like epoxy, hydroxyl, ether during the curing was followed by IR-spectrometric analysis. The performance of the cured coatings has been determined. It was showed that increase of the EBSO/BCDE weight ratio from 20/80 to 80/20 led to changes both photocrosslinking and properties of investigated coatings: Consumption of total epoxy groups from 4.62 to 0.77 mole/kg, gel fraction from 76.9 % to 73.25 %, swelling degree from 235 % to 559 %, relative hardness from 0.84 to 0.16, flexibility from 10 to 1 mm, impact resistance from 5 to 60 kG.cm while gloss at 60(o) remained to be 100 % after 1.2s of UV- exposure.