Reversing Poisson’s Ratio of Biomass Foam to Be Negative to Achieve Super Mechanical Properties via Viscoelastic Compression

We proposed a strategy to transform a cell shape from convex to concave via viscoelastic compression in order to reverse the Poisson’s ratio of biomass foam to be negative and improve its properties in compression and shockproof. The poly­(butylene succinate) (PBS) foam with a negative Poisson’s ratio (NPR) was prepared; the Poisson’s ratio reached −0.7, and the compressive modulus increased by 359%. In the shockproof field, the storage and loss modulus could increase by ca. 270% and 350%, respectively. Such a method of viscoelastic compression can be universal for the reinforcement of biomass foam materials.