UV-Cured Functional Coatings

Abstract

The UV-induced polymerization of multifunctional monomers has found a large number of industrial applications, 1 mainly in the production of films, inks and coatings on a variety of substrates including paper, metal and wood. Moreover, it has demonstrated scope for more high-tech applications such as coating of optical fibers and fabrication of printed circuit boards.Part of the reason for the growing importance of UV-curing techniques, both in industrial and academic research, is a peculiar characteristic 2,3 that induces fast transformation of a liquid monomer into a solid polymer film having distinctive physical-chemical and mechanical properties. It can be considered environmental friendly owing to the solvent-free methodology, and is usually carried out at room temperature, thus conferring added energy-saving advantages.During a UV-curing process, radical or cationic species are generated by the interaction of UV light with a suitable photoinitiator, and subsequently a radical chain-growth polymerization or a cationic ring-opening polymerization process take place. In this chapter we will outline a literature survey where UV-curing techniques have been used for the production of functional coatings.

Sustainable access to fully biobased epoxidized vegetable oil thermoset materials prepared by thermal or UV-cationic processes

“…The UV curing process is getting an increasing importance in different elds such as inks, adhesives and coatings on a variety of substrates, including paper, metal, plastic and wood. 19 This polymerization technique can be exploited to reach a fast transformation of the liquid monomer into the crosslinked polymeric lm with tailored thermomechanical properties. While acrylated and methacrylated monomers are employed for radical photocuring process, the epoxy monomer are the most important reactive moieties in cationic photoinduced crosslinking reaction.…”

“…It is worth mentioning the reduced energy consumption, high cure speed even at room temperature and absence of VOC emission. [18][19][20] More, investigating and comparing both hardener-free thermal and photo-induced curing processes allow evaluating the inuence of the crosslinking mechanisms on the thermo-mechanical properties of EVOs based thermoset materials.…”

Recent advances on pyrene-based photoinitiators of polymerization

“…As other appealing feature, photopolymerization can also be carried out without solvents, enabling to drastically reduce the amount of released volatile organic compounds (VOC). [72][73][74][75][76][77] If visible light photoinitiators are presently so popular, this is also related to the cure depth which is directly correlated to the wavelength of irradiation. [78] O As evidenced in the Figure 2 for a polystyrene latex with an average diameter of 112 nm, the light penetration can range between 600 µm in the UV range to 5 cm in the nearinfrared region, revolutionizing the scope of applications of photopolymerization.…”

Light Processable Starch Hydrogels

“…Photocuring techniques are green and highly efficient for crosslinking polymer resin with photo-curable functional groups. They have many advantages with respect to the thermocuring processes such as absence of Volatile Organic Compound (VOC) emissions, high curing speed, reduced energy consumption, and no heat requirements [ 13 , 14 , 15 ]. Recently UV curable biopolymer-resins have gained increasing interest [ 16 , 17 ].…”