Investigation of the mechanical, thermal, morphological and rheological properties of bio-based polyamide11/poly(lactic acid) blend reinforced with short carbon fiber

This paper, reports the fiber length distribution, morphological, mechanical, thermo-mechanical, and rheological properties of partially bio-based and biodegradable polyamide 11/poly(lactic acid) (PA11/PLA) (60/40 wt/wt) blend in the presence of different amounts of carbon fiber (CF). Loading ratios of CF were altered as 10-20-30 wt %. Samples were prepared with extrusion and injection molding. The average fiber length in the matrix decreased with the increasing amount of CF. The morphological analysis showed a good interfacial interaction between the matrix and CF. As a result of this interaction the tensile strength, elastic modulus, and temperature dependence storage modulus of PA11/PLA blend improved with the addition of CF. The tan S curves obtained as a result of the dynamic mechanical analysis showed that the T-g value of the matrix shifted to higher values with increasing CF amount. In addition, the reinforcement effect and entanglement density increased with increasing CF. The complex viscosities and modulus of PA11/PLA/CF composites were higher than the matrix which indicates that CF enhanced melt strength and stiffness of the PA11/PLA matrix.