Toward sustainable SLA 3D printing: glycerol-based 1,3-diether-2-methacrylates with solvent capability for in situ polymer blend formation

Abstract

Development of sustainable and environmentally friendly stereolithography (SLA) 3D printing resins has gained considerable attention in recent years. Towards this goal, we have successfully employed glycerol-based 1,3-diether-2-methacrylate monomers that offer tunable mechanical and thermal properties. These monomers also act as solvents for thermoplastics such as polystyrene (PS) and poly(methyl-methacrylate) PMMA. This dual functionality enables the direct fabrication of polymer blends using only a consumer-level SLA 3D printer. The resulting blends exhibit composition-dependent phase morphologies that significantly influence mechanical properties. For instance, incorporating 5 wt% waste PS (wPS) results in complete phase separation with a stratified morphology in each layer and substantially diminished elongation at break, whereas 10 wt% wPS led to a more uniform dispersion and improved mechanical behavior. In contrast, PMMA-containing systems provide more transparent blends and continuous matrix morphology without compromising elasticity. Thermal analysis revealed the presence of two distinct glass transition temperatures (T_g) corresponding to the matrix formed via monomer curing and the thermoplastic phase, confirming the immiscibility of the blends. However, shifts and broadening of T_g values indicate improved interfacial interactions across the studied composition range. These results highlight the potential of glycerol-based methacrylate monomers as multifunctional platforms for tunable resin formulations and sustainable SLA 3D printing.