Nanofibrillated cellulose reinforced polypropylene carbonate biocomposites with high mechanical properties, dimensional stability, and antibacterial properties

Abstract Polypropylene carbonate (PPC) is a biodegradable polyester with excellent toughness and ductility that may be employed as carbon fixation materials in biomedicine, agriculture, and environmental engineering. However, relatively lower strength and poor dimensional stability hinder its extensive application. In this study, nanofibrillated cellulose (NFC) and chitosan (CS) were introduced as biobased reinforcements into PPC without compromising its biodegradability. Notably, the composites not only had improved strength but also enhanced toughness after the addition of NFC and CS. The tensile strength and Young's modulus were increased by 25% and 58% in the composites with 3 wt% NFC and 2 wt% CS additions compared to pure PPC. Interestingly, the PPC/NFC/CS composites exhibited superior dimensional stability and antibacterial property. Upon the addition of 3 wt% NFC and 2 wt% CS, the composites took 3 s recovering from 0° to 137°. Additionally, NFC and CS contribute to the hydrophilicity of PPC composites. These findings offer valuable insights into experimental data and preparation techniques to the utilization of PPC in engineering fields. Highlights The developed composites achieved maximum tensile strength (13.5 MPa). The composites with 2 wt% chitosan had effective antibacterial properties. All reinforced composites showed excellent dimensional stability. Nanofibrillated cellulose and chitosan had toughening and enhancing effect. The developed composites showed good hydrophilicity.