Additive manufacturing of hygromorphic structures using regenerated cellulose/PLA biocomposites

Three-dimensional printing technologies are at the forefront of current industrial revolution, enabling production complex shapes using a wide range materials without relying on large facilities. Evolving from these, 4D is new concept in which printed objects respond to environmental stimuli and change shape or other characteristics with time controlled predicted manner. Bioderived and/or biodegradable thermoplastics reinforced bioderived fibres have compelling attributes for 3D applications; they can be recycled, used smart (4D printing) if necessary, biodegrade end their life cycle. In this work, we demonstrate potential use biocomposites based poly(lactic acid) (PLA) high content regenerated cellulose (lyocell) hygromorphic structures, fused deposition modelling (FDM). The shape-change was assessed by bi-material strips passive active layers composed neat PLA composite, respectively measuring curvature increase water absorption. main mechanism involved behaviour related anisotropic swelling that preferentially aligned composite during printing. Using layout, prototypes different sizes 2D transformation triggered moisture were printed.