High-Performance\nBiobased Electronic Packaging Coatings\nEnabled by Unlocking the Photo-Cross-Linking Capacity of Lignin-Derived\nEpoxy Resin

Substantial interest in producing thermosets and photoresponsive\nchemicals from bioresources is garnering, yet moderate performance\ndrastically confines their applicability in electronic packaging material.\nHerein, several thermosetting epoxy building blocks from lignin-derived\nmonomers (vanillyl alcohol and eugenol) were constructed, and a range\nof lignin-based enhanced photocurable resins were further developed\nusing acrylic acid and tetrahydrophthalic anhydride as modifiers by\nan one-pot synthesis method. The comprehensive performance of lignin-based\nfunctionalized photocurable resins was systematically investigated,\nsuch as their photopolymerization behavior, thermal–mechanical\nproperties, and electrical breakdown properties. As a result, the\nbiobased thermosetting resin stemming from vanillyl alcohol monomers\nfulfilled fascinating heat resistance (<i>T</i><sub>g</sub> ≈ 103.9 °C) and tensile strength (28.89 ± 4.39\nMPa). Additionally, inspired by a tunable chain-extending tactic,\nthe toughness and electrical breakdown strength of the biobased photo-cross-linked\nfilms were further intensified by the insertion of flexible alkyl\nchain segments between cross-linked sites. As proof of concept, the\nformulated EAAT green ink, consisting of photocurable resin and inorganic,\ndemonstrated a superior patterning ability after alkali development.\nThe rationally designed lignin-derived photo-cross-linked network\nstrengthening mechanism reported here offers an important and universal\nstrategy for significantly enhancing the comprehensive properties\nof biobased photocurable materials.