A Thermoreversible Gelation Pathway to Plant Cuticle‐Inspired Biopolymer Aerogel Monoliths Based on Network‐Spherulitic Crystal Assemblies

ABSTRACT

Plant‐based and compostable biopolymers are vital in global shifts toward green materials. However, their adoption in aerogel fabrication is limited by material and structure‐performance deficiencies (e.g., hydrophilicity, low surface area, brittleness, limited tactile tailorability). Nevertheless, stereocomplexation, or co‐crystallization between polymeric enantiomers, offers a pathway toward overcoming such limitations. Herein, stereocomplexation is used to fabricate poly(lactide) (PLA)‐based aerogels, with stereocomplex crystals (SCs) assembling into a highly ordered morphology/topology within aerogel precursors. To tailor aerogel bulk properties, a blending approach is implemented during sol–gel processing, leading to sequential crystallization of sol–gel system constituents. This pathway yields hierarchically macro‐/meso‐porous aerogels ( S _BET up to ∼186 m ² ·g ⁻¹ ), offering a variety of superstructures that resemble cuticular plant tissue. These aerogels resist brittle failure under compression (70% strain) and withstand cyclic loading (100 cycles, 20% strain) without significant densification. Such aerogels also exhibit functional properties including superhydrophobicity/superoleophilicity and are well‐suited for continuous oil–water separation. Additionally, fantastic geometric‐thermal stability, insulation/heat dissipation ability ( k _Cond  ∼36 mW·m ⁻¹ ·K ⁻¹ ), and phase‐change insulation characteristics are achieved. These functionalities arise from multi‐scale structural features and demonstrate how coupling stereocomplexation and sequential crystallization offers pathways to construct intricate superstructure morphologies/topologies, and overcome material/structure‐performance limitations in green aerogels.