Structure and Properties of Paint Coatings Irradiated by Ultraviolet Light

The paper presents research data of the UV-radiation effect on the structure formation and physical-mechanical properties of paint coatings formed from the industrial EP-773 two-component epoxy enamel. The coatings have been modified with active hollow glass microspheres (Q-cel 6048) and have been irradiated with UV light (207 nm). A relevance of the work associated with the need of improvement coating producing technologies and development protective paints with required performance characteristics. By the method of scanning electron microscopy it was found that addition of the microspheres in the industrial EP-773 two-component epoxy enamel leads to decrease in a number of micro cracks and their extending in a volume of paint coatings. It is shown that hardness of paint coatings with the hollow glass microspheres is higher. It has been established that hollow glass microspheres improve the hiding power of the paint coatings, while maintaining a high level of an adhesion and an impact strength, thereby contributing to save paint coatings and to increase their service period due decreasing in the amount of corrosion products on their surfaces. It is obtained that effect of the UV radiation (wavelength 207 nm) on the surface of paint coatings formed from the industrial EP-773 two-component epoxy enamel modified with active fillers leads to structure destruction primarily near microspheres due to occurring extra internal stresses and promotes to derivation of polymer crosslinking due to the successive addition of free-radical building blocks. The experimental date indicate that UV irradiation of coatings surface deposited from EP-773 two-component epoxy enamel with glass microspheres promotes forming uniformly, dense and non-porous paint coatings with decreased hardness but with extra corrosion protection.