Innovative polypropylene based blends by in situ polymerization of a polyimide dispersed phase by reactive extrusion

Polypropylene/polyimide (PP/PI) blends were synthesized by reactive extrusion with the in situ polymerization of polyimide phase presence maleic anhydride grafted polypropylene (PP-g-MA) as a compatibilizer. Blends reactively processed twin-screw extruder at 200 °C, PI content varying from 10 to 40 wt%. Examination morphology scanning electron microscopy (SEM) depicted fine sub-micrometer dispersion ranging 170 250 nm diameter, for all concentrations. The advantage approach compared more classical process was clearly demonstrated. characterized NMR and FTIR after separation Soxhlet selective extraction. Differential calorimetry (DSC) analysis showed no modifications PP crystallinity addition PI. Rheological behaviors significant impact on storage modulus appearance secondary plateau low frequencies. Thermogravimetric analyses evidenced an improvement thermal stability blends, increase decomposition temperature up 35 °C depending content. Mechanical properties also improved due high mechanical strength phase, Young's +35 % highest