Thermal behavior of PP/PA6 blends under dynamic conditions. The effect of different interfacial agents based on chemically modified atactic polypropylene

The thermal behavior in dynamic conditions of polypropylene/polyamide 6 (PP /PA6) blends with a modified interphase is discussed in terms of the crysta llinities of the polypropylene and polyamide components imposed by the proc essing step conditions and after removal of those constraints by holding th e blends 5 min in the molten state in the calorimeter. As interfacial agent s, two based on succinic anhydride or succinil-fluoresceine grafted atactic polypropylenes were used. The experimental program was run following the B ox-Wilson experimental design methodology. Thermal scans were made using ro und samples (5 min diameter and 100 mum thick) cut from compression-molded sheets with morphologies and macroscopic behavior studied previously. Chang es of the amount of crystallinity of each polymer in the modified blends ar e contrasted with the tensile strength values of the heterogeneous material s as a whole; evidence of the different roles played by each interfacial ag ent acting at the interface among blend components is shown.