Dual functional anti-oxidant and SPF enhancing lignin-based copolymers as additives for personal and healthcare products

Abstract

The desire for protection against UV exposure has resulted in the development of an increasing number of sunscreen agents. Lignin-based polymers have potential to serve as promising sunscreen agents as they have good UV absorption and antioxidant properties contributing towards the reduction of UV-induced skin damage. In this study, a series of lignin–poly(ethylene glycol) methacrylate (PEGMA) copolymers were synthesized via atom transfer radical polymerization (ATRP) to enhance the dispersion efficiency of lignin in the commercial creams. These copolymers showed tunability in both molecular weight (10–25 kDa) and particle size (100–200 nm), as well as excellent antioxidant properties. Different amounts of such copolymers were blended into commercial creams to investigate their sunscreen performance. Results indicated that adding lignin–PEGMA copolymers into sunblock creams improved their SPF values from 15.36 ± 2.44 to 38.53 ± 0.26. In summary, such lignin-based polymers with good UV protection and antioxidant properties offer a green alternative for developing the next generation of sunscreen creams.