Weathering of compatibilized poly(hydroxybutyrate)/agave fiber biocomposites produced by different mixing methods

The continuous growth in the biopolymers market underscores the necessity to develop and characterize novel materials to replace conventional polymers. This study evaluated the effect of the processing method on the properties of poly(hydroxybutyrate)/agave fiber (PHB/AF) biocomposites with a coupling agent based on glycidyl methacrylate. The components were first blended using two methods (dry-blending and twin screw-extrusion) before being compression molded. Then, the biocomposites degradation was evaluated via accelerated weathering to determine its effect on the physico-mechanical properties. The results showed that adding AF to PHB increased the porosity (low density), but this effect was decreased by 60% for the extruded compatibilized biocomposites. Consequently, the level of degradation (loss of mechanical properties and dimensional stability) was less affected when a coupling agent was used. However, after weathering, the porosity similarly increased for both uncompatibilized biocomposites. Finally, the tensile, impact, and flexural strength were less affected by weathering when the compatibilizer was mixed via dry-blending.