A Multicomponent Strategy for Tough, Functional, and Biodegradable Natural Elastomeric Biogels

ABSTRACT Natural polymers are attractive building blocks for sustainable soft materials, yet it remains fundamentally difficult to make them simultaneously tough, functional, and biodegradable. In most cases, natural soft materials are mechanically weak or functionally limited, while strategies that improve one attribute often compromise another. Here, we present a water‐assisted multicomponent design strategy that overcomes this trade‐off and enables a new class of natural elastomeric biogels from simple bio‐derived components. In this approach, water serves primarily as a transient processing medium that enables rapid homogeneous mixing of guar gum, betaine, urea, and malonic acid (GBUM), followed by evaporative assembly into a low‐water‐content, amorphous elastomeric biogel rather than a conventional water‐rich hydrogel. The stable regime is attributed to a combination of competitive hydrogen bonding, ion–dipole interactions, polymer confinement, additive diversity, and retained bound water, rather than a single dominant interaction. The resulting materials exhibit high toughness (up to 5.23 MJ m − 3 ), ionic conductivity (up to 2.3 mS/cm), and subzero resilience (−40°C), while retaining rapid aerobic biodegradation in soil (80% in 7 days). Importantly, the same additive concept extends to other natural polymer matrices, supporting a broader materials design principle rather than a single optimized formulation. These results establish controlled multicomponent assembly as an effective route to tough, functional, and biodegradable natural soft materials with promising relevance for soft ionic devices and bioelectronics.