Mechanical response of PHB- and cellulose acetate natural fiber-reinforced composites for construction applications

Biobased composites are being evaluated for construction applications where wood or petroleum-based composites are currently used. The biobased composites studied are made from biopolymers and plant-based fibers and have been demonstrated to rapidly biodegrade in anaerobic conditions to methane thereby reducing construction-related landfill waste and producing a useful end product, namely fuel for energy or feedstock to grow more biopolymer. Mechanical properties are evaluated for hemp fabric/cellulose acetate and hemp fabric/poly(hydroxybutyrate) (PHB) composites. The composites have comparable strength to structural lumber and engineered wood products, with stiffness comparable to most engineered wood products. Classical laminate plate theory sufficiently predicts initial laminate behavior from ply-level experimental data. Simple nonlinear models using laminate plate theory and uncoupled ply-level experimental constitutive response are evaluated.