Syntheses of donor acceptor biobased photocurable water‐soluble resins based on poly‐l‐lysine

We report a new kind of coating using UV waterborne technique with a biobased poly(amino acid) resin. Firstly we performed the thermal polycondensation of l ‐lysine during 15 h at 150 °C to synthesize water‐soluble oligomers of poly‐l ‐lysine (PLL) with 5–6 monomer units. These oligomers were then transformed in mild conditions to give photocurable water‐soluble resins. We grafted on the poly‐l ‐lysine backbone, allyl and maleamic acid functional groups, with a grafting rate close to 65% thanks to allyl glycidyl ether and maleic anhydride respectively. The influence of the reaction time and the reagents ratio on the grafting rate was investigated. Hence, the donor/acceptor photopolymerization of the mixture of allyl ether‐poly‐l ‐lysine (PLL‐g‐AE) with maleamic acid‐poly‐l ‐lysine (PLL‐g‐MA) in aqueous solution gave yellow transparent films. The degree of conversion and other kinetic parameters have been studied and detailed. This work contributes to the development of materials based on renewable resources and cleaner processes. It opens a new pathway to both fundamental and applied‐driven research. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 955–963