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The preparation of biodegradable polymeric materials with both great strength and toughness remains a huge challenge. The natural spider silk exhibits a combined super high tensile strength and high fracture toughness (150–190 J g−1), attributing to the hierarchically assembled nanophase separation and the densely organized sacrificial hydrogen bonds confined in the nanoscale granules. Herein, inspired by natural spider silk, a facile strategy is reported for the preparation of nanostructured biomimetic polymeric material by incorporating biomass‐derived lignosulfonic acid (LA) as interspersed nanoparticles into a biodegradable poly(vinyl alcohol) (PVA) matrix. The fabricated PVA/LA nanocomposite film exhibits the world's highest toughness of 172 (±5) J g−1 among the PVA materials, as well as a powerful tensile strength of 98.2 MPa and a large breaking strain of 282%. The outstanding performance is attributed to the strain‐induced scattering of LA nanoparticles in the PVA matrix and the strong intermolecular sacrificial hydrogen bonds confined in the interphase. Moreover, after introducing the easily available green biomass LA, the prepared biomimetic polymer films show excellent ultraviolet‐blocking performance and good thermal stability. As both PVA and LA are biodegradable, this work presents an innovative design strategy for fully biodegradable robust polymeric materials with integrated strength and toughness.

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This study conducted an investigation of the effect of lignosulfonate (LS) on enzymatic saccharification of lignocelluloses. Two commercial LSs and one laboratory sulfonated kraft lignin were applied to Whatman paper, dilute acid and SPORL (sulfite pretreatment to overcome recalcitrance of lignocelluloses) pretreated aspen, and kraft alkaline and SPORL pretreated lodgepole pine. All three lignin samples inhibited cellulose saccharification of Whatman paper, but enhanced the saccharification of the four lignocellulosic substrates. The level of enhancement was related to the molecular weight and degree of sulfonation of the lignin as well as the substrate lignin structure. When different molecular weight (MW) fractions of one commercial LS (SXP), generated from sulfite pulping of hardwood, were applied to the Whatman paper, the large MW fraction (SXP1) with the lowest degree of sulfonation inhibited cellulose saccharification while the intermediate (SXP2) and smallest (SXP3) MW fractions enhanced saccharification. All MW fractions enhanced saccharification of the four lignocellulosic substrates with maximal enhancement by the smallest MW fraction, SXP3. The enhancement was most significant for the kraft lodgepole pine substrate and least significant for the SPORL pretreated lodgepole pine using all three LS and SXP fractions. The results suggest that LS acts as a surfactant to enhance pure cellullose saccharification. When LS is applied to lignocelluloses, it acts as a surfactant to block bound lignin from binding cellulase nonproductively leading to enhanced saccharification.

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