A micromechanical model of cellulosic foams – validation and results of first parametric studies

Cellulosic network structures are a potential sustainable and ecological alternative to current synthetic foams. The EU funded project ‘BreadCell’ explores porous cellulosic structures generated through a biological foaming process employing yeasts.

The development of the material is assisted through a micro-mechanical model of the structure, which is influenced by numerous parameters – related to the fibre (length, cross-section, kinks, curls, fibrillation, strength and stiffness) and the morphology of the network (pore size, relative pore volume).
A tool was developed that automatically generates a micromechanical model representative of the fibrous structure for a given set of fibre and foam parameters. The generator returns a runnable input deck of the bulky or planar fibrous network structures.

The numerical model was validated against data from experimental tests of planar and bulky cellulosic network structures. Parametric studies were conducted, showing that fibrillation and the pore structure are key parameters to increase stiffness and strength of the foam. In future work the modelling approach will be tested in different load configurations