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We report the preparation of a furan polymer, poly(2,5-furandimethylene succinate) by means of a condensation reaction between bio-based monomers. A reversible Diels–Alder reaction between furan and maleimide groups allowed the formation of network polymers cross-linked by a bismaleimide. By controlling the amount of the bismaleimide, mechanical properties were varied widely. These network polymers healed well when their broken surfaces were activated by bismaleimide solutions or solvent. The polymers also displayed excellent self-healing ability without external stimulus. This polymer class offers a wide range of possibilities to produce materials from biomass that have both practical mechanical properties and healing ability. These materials have the potential to bring great benefits to our daily lives by enhancing the safety, performance, and lifetime of products.

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We describe experiments that probe the evolution of shear jammed states, occurring for packing fractions [symbol: see text](S) ≤ [symbol: see text] ≤ [symbol: see text] J, for frictional granular disks, where above [symbol: see text]J there are no stress-free static states. We use a novel shear apparatus that avoids the formation of inhomogeneities known as shear bands. This fixed [symbol: see text] system exhibits coupling between the shear strain, γ, and the pressure, P, which we characterize by the "Reynolds pressure" and a "Reynolds coefficient," R([symbol: see text]) = (∂(2)P/∂γ(2))/2. R depends only on [symbol: see text] and diverges as R ~ ([symbol: see text])c - )(α), where [symbol: see text](c) ~/= [symbol: see text](J) and α ~/= -3.3. Under cyclic shear, this system evolves logarithmically slowly towards limit cycle dynamics, which we characterize in terms of pressure relaxation at cycle n: ΔP ~/= -βln (n/n(0)). β depends only on the shear cycle amplitude, suggesting an activated process where β plays a temperaturelike role.

Academics researchers and "citizen scientists" from 22 countries confirmed that yellow mealworms, the larvae of Tenebrio molitor Linnaeus, can survive by eating polystyrene (PS) foam. More detailed assessments of this capability for mealworms were carried out by12 sources: five from the USA, six from China, and one from Northern Ireland. All of these mealworms digested PS foam. PS mass decreased and depolymerization was observed, with appearance of lower molecular weight residuals and functional groups indicative of oxidative transformations in extracts from the frass (insect excrement). An addition of gentamycin (30 mg g), a bactericidal antibiotic, inhibited depolymerization, implicating the gut microbiome in the biodegradation process. Microbial community analyses demonstrated significant taxonomic shifts for mealworms fed diets of PS plus bran and PS alone. The results indicate that mealworms from diverse locations eat and metabolize PS and support the hypothesis that this capacity is independent of the geographic origin of the mealworms, and is likely ubiquitous to members of this species.