Environmentally acceptable and renewably sourced flame retardants are in demand. Recent studies have shown that the incorporation of the biopolymer lignin into a polymer can improve its ability to form a char layer upon heating to a high temperature. Char layer formation is a central component of flame-retardant activity. The covalent modification of lignin is an established technique that is being applied to the development of potential flame retardants. In this study, four novel modified lignins were prepared, and their char-forming abilities were assessed using thermogravimetric analysis. The lignin was obtained from date palm wood using a butanosolv pretreatment. The removal of the majority of the ester groups from this heavily acylated lignin was achieved via alkaline hydrolysis. The subsequent modification of the lignin involved the incorporation of an azide functional group and copper-catalysed azide–alkyne cycloaddition reactions. These reactions enabled novel organophosphorus heterocycles to be linked to the lignin. Our preliminary results suggest that the modified lignins had improved char-forming activity compared to the controls. ³¹P and HSQC NMR and small-molecule X-ray crystallography were used to analyse the prepared compounds and lignins.

Controlled oxidation of lignin from Sitka spruce.

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.

To mitigate the effects of climate change, it is essential to discover and design materials which can capture CO2effectively. Placing sustainability at the forefront of the design of these materials is essential to lessen environmental impact and can be achieved by rethinking the approach to discovery and design. Here, we have established an integrated, sustainability-guided workflow for the rapid discovery of biomass-derived metal-organic frameworks (MOFs) that can be readily adapted to other materials challenges. The workflow combines renewable feedstock selection, green synthesis principles, quantitative sustainability benchmarking, machine learning-guided property prediction, rapid structural characterization, and automated synthesis to accelerate sustainable materials development. As a proof-of-concept, we discovered Toronto Framework-1 (TORF-1), a new porous MOF synthesized from divanillic acid (DiVA), a lignin-derived renewable feedstock, in only 5 minutes under ambient conditions in ethanol with an industrially relevant ultra-high space-time yield (STY) of 5702 kg m-3 day-1. Sustainability metrics quantify the environmental advantages of the synthetic route and provide a practical strategy for benchmarking MOF sustainability. XRayPro, a multimodal machine learning system leveraging powder X-ray diffraction patterns and precursors to make property predictions, rapidly identified TORF-1 as a promising CO2 sorbent, which was subsequently validated experimentally with a CO2 uptake of 1.937 mol/kg at 1 bar and 288 K. High-throughput serial electron diffraction (SerialED) enabled rapid structural determination, while integration with an automated synthesis platform provides future potential for accelerated reaction optimization through in situ monitoring. Together, these advances establish a generalized sustainability-guided workflow for accelerating MOF discovery and scalable synthesis that can be readily extended to other porous materials and applications beyond carbon capture.