Optimization in the reprocessing of recycled polyamide 6 reinforced with 30 wt% Glass Fiber (PA6/GF30) using mixture design
In the present study, polyamide 6 reinforced with 30?wt% Glass fiber (PA6/GF30) used in automotive industry was reprocessed via injection molding. The virgin and recycled PA6/GF30 samples were characterized by chemical, rheological, mechanical, and morphological properties as a function of the number of processing cycles. After each reprocessing cycle, a decrement in mechanical properties in tensile, bending, and impact strength was revealed for different combination of cycle number (N0 [for the virgin PA6/GF30], N1 [for the first recycled PA6/GF30], N2 [for the second recycled PA6/GF30], and N3 [third recycled PA6/GF30 sample]) in the composite mixture. A simplex?centroid mixture design (SCMD) was used to evaluate the effect of combining Ni (i=0,1,2) on the mechanical properties of composite samples for optimization. Graphical comparison of experimental results using regression models showed a high degree of correlation. Results revealed that the ternary N0?N1?N2 blends composite made up of 67.97?wt% N0, 23.13?wt% N1, and 8.89?wt% N2 exhibited the best mechanical properties. Furthermore, a good correlation between the scanning electron microscopy (SEM) observations and tensile test results was observed. Hence, the new reprocessed formulation presents a cost?effective alternative of virgin PA6/GF30 for different engineering applications.