Effect of organoclay and corn straw on the properties of poly (butylene adipate-co-terephthalate) (PBAT) hybrid composites

Abstract

The packaging industry requires permeable materials capable of offering freshness of the packaging content. The use of fillers can enhance these permeable properties to the polymeric material. This work investigates the effect of incorporating different fillers (organophilic clay and corn straw) on the rheological, mechanical, permeability, water absorption and biodegradability characteristics of poly (butylene adipate co-terephthalate) (PBAT) processed in an internal laboratory mixer. Extruded films and specimens injection molded were produced. The results of torque rheometry suggest polymer matrix degradation during processing slightly increase, also evidenced by MFR results. Composite films showed a drop in tensile strength, higher stiffness and lower elongation. Incorporation of the fillers in the PBAT matrix enhanced the permeability to oxygen gas of the produced films. The presence of fillers significantly increased the capacity of water absorption. The incorporation of C20A and, mainly, CS tends to accelerate the biodegradation of PBAT. Adding small amounts of organoclay C20A and CS to PBAT leads to a material that combines maintenance or improvement of biodegradation combined with higher permeability to oxygen, which indicates the potential use of these systems in packaging industry for maintenance of freshness of content.