Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Cryo-milled powdered PBAT is a key approach to accomplish better dispersion of Hemp fiber in PBAT/Hemp fiber composites, and these bio-based composites with enhanced stiffness show the feasibility to be suitable for the rigid packaging field requiring the thermo-forming process.

ABSTRACT
Poly(butylene adipate-co-terephthalate) (PBAT) has attracted significant attention due to its excellent flexibility and biodegradability. However, its high cost and low stiffness remain drawbacks for packaging applications. Recent research has focused on developing natural fiber reinforced composites to improve the stiffness of PBAT. However, the poor dispersion of natural fibers in the polymer matrix and interfacial phenomena have a great effect on the physical and mechanical properties of composites. In this study, excellent physical and mechanical performance were achieved through superior dispersion of Hemp fiber (HF) with cryo-milled PBAT powder. The dynamic mechanical analysis and high temperature tensile tests were especially conducted to assess the feasibility of PBAT/HF composites for thermoforming behavior. Young's modulus of the PBAT composites enhanced from 83 MPa to 703 MPa, approximately 747%. In particular, as compared with PH30, wPH30 exhibited an additional enhancement of about 7.2%. It was confirmed that the PBAT powder/HF composites showed better mechanical properties than the PBAT pellet/HF composites, showing more effectiveness in improving the stiffness of PBAT, and this was attributed to the fact that PBAT powder improved interfacial adhesion and dispersion as well. The addition of HF slightly decreased the thermal stability of the composites.