4. Conclusion
In this paper, the investigation of P(VDF-ter-HFP-ter-TFE) terpolymer additive on Al/MnO2nanothermite system was presented. The terpolymer can stick nanothermite components together to enhance the integrality of materials. The thermal properties can be significantly influenced by the contents of P(VDF-ter-HFP-ter-TFE) terpolymer. Without any terpolymer additive, thermite reaction between Al and MnO2 occurred at about 554 oC. For 10wt% mass fraction of terpolymer, three exothermic signals appeared before the main thermite reaction, indicating the thermal reactions among Al nanoparticles, MnO2 nanorods, terpolymer degradation products and/or the terpolymer matrix. However, those three thermal reactions became the main exothermic reaction instead of thermite reaction when the content of terpolymer was over 20wt%, and the residues analysis verified the difference. The main reaction products of Al/MnO2nanothermite were Mn3O4, MnO and Al2O3. For Al/MnO2/10wt%- terpolymer, the residues were MnAl2O3 and Al2Mn3. When the content of terpolymer was more than 20wt%, such Mn7C3 and AlF3 were found in the residues. The ignition and combustion processes were also different accordingly. The terpolymer could reduce the ignition energy threshold but also decrease the speed of flame growth. The terpolymer could hinder the direct contact of nanothermite components and influence the flame spread. This work revealed the thermal and combustion performance of Al/MnO2/ P(VDF-ter-HFP-ter-TFE) terpolymer nanothermites, which could provide a reference for application of fluoroelastomer in energetic materials.