Influence of photoinitiator and curing conditions on polymerization kinetics and gloss of UV-cured coatings

Abstract

Polymerization kinetics and gloss of different formulations of coatings at different UV curing conditions were studied. The results showed that the photoinitiator type, its concentration, sample coating thickness, as well as the UV light intensity were the most significant factors affecting the polymerization course and the gloss of UV-cured films. The increasing concentration of the photoinitiator and the UV light intensity significantly decreased the gloss of the cured surface. The influence of the sample coating thickness on the kinetics and final gloss was also considerable.

Preparation of a crosslinked coating containing fluorinated water-dispersible polyurethane particles

“…This is an important property of coatings especially for decorative purposes, and a high-gloss is typically achieved with a smooth coating that does not possess micro-or nano-roughness [46]. The surface is considered semi-matt if the gloss value is in the range of 30-70 GU, and the surface is considered high-gloss if the value is over 70 GU [47]. As shown in Fig.…”

Preparation of coatings from a series of silicone/fluorine‐functionalized polyacrylates via electrophoretic deposition

“…This is an important property of coatings, especially for decorative purposes, and high glossiness provides the coated materials with an attractive appearance. The surface is considered semi‐matt if the gloss value is in the range of 30–70 GU, and the surface is considered high gloss if the value is over 70 GU . The effects of TIVS and FEMA contents on the glossiness of the coatings were investigated, and the results are summarized in Fig.…”

Development of Photocurable Polyacrylate-Based PolyHIPEs and the Study of the Kinetics of Photopolymerization, and of Their Thermal, Mechanical and Hydrocarbon Absorption Properties

“…All formulations displayed a similar photopolymerization rate, when the concentration of photoinitiators was varied in the T-E (1:3) HIPEs (Figure 4b), though the HIPEs with 2.0 mol% of both photoinitiators displayed lower reactivity, while the formulation with 0.25 mol% of both photoinitiators showed the highest. Due to the high reactivity of the T-E formulations, conversions of 99%, 98%, 98% and 94% were attained for the formulations with increasing concentration of photoinitiators, after 1200 s. This can be attributed to the rapid build-up of the crosslinked network in the highly viscous media of the HIPE, due to the high concentration of free radicals, hindering the propagation reactions, which results in a decrease in the photopolymerization rate [54,55]. A disadvantage of using high concentration of photoinitiators is the increase in the levels of yellowing.…”