The growing pursuit of carbon circularity in material fabrication has led to the increased use of recycled and biobased resources, especially in epoxy resin systems. Fossil-based bisphenols are being replaced with recycled bisphenol A (r-BPA) and lignin derivatives, both derived from previous processes. In this study, r-BPA was chemically recycled from end-of-life televisions, then converted into r-DGEBA and r-DAGBA through glycidylation and acrylic acid ring-opening. These monomers were used to create six thermosets by reacting Jeffamine D230 with r-DGEBA/r-DAGBA in varying epoxide:acrylate ratios. Acrylates introduced thermo-reversible β-amino esters, enabling dynamic bonding in the epoxy formulation. To increase biobased content, glycidylated depolymerized lignin (GDL) was added to produce five additional polymers. The crosslinked networks were thoroughly characterized, examining their thermomechanical properties and establishing a structure-property relationship. The dissociative acrylate-amine interactions allowed for reversible crosslinks under specific thermal conditions, enabling shape programming and crosslink reversibility. The study demonstrates that incorporating recycled and biobased aromatic monomers facilitates the creation of dynamic, crosslinked structures with tunable properties. This represents progress toward versatile, reusable, and circular materials.
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