Modified Polyaniline and Its Effects on the Microstructure and Antistatic Properties of PP/PANI-APP/CPP Composites

Polypropylene (PP) composites that contain poly(aniline) (PANI) and ammonium polyphosphate crystalline form II (APP-II) have both antistatic and flame-retardant properties. In the present study, double anti-functional PANI was prepared via in situ polymerization in the presence of APP-II. Analysis of the Fourier transform infrared spectra demonstrated that PANI was synthesized successfully with APP-II and that modified PANI (PANI-APP) was obtained. Next, PP/PANI-APP/chlorinated poly(propylene) (CPP) and PP/PANI/CPP composites were prepared. The results showed that the volume resistivity of the PP/PANI-APP/CPP composite was at least 100 times less than that of the PP/PANI/CPP composite. The microstructures of the corresponding composites were investigated carefully by scanning electron microscopy and wide angle X-ray diffraction. The areas of the conductive regions and the percentage crystallinity of PP in the PP/PANI-APP/CPP composite were distinctly higher than those in the PP/PANI/CPP composite, i.e., by about 10% and 7%, respectively. In addition, experimental analyses of the limiting oxygen index and thermogravimetry showed that the PP/PANI-APP/CPP composite had advantages compared with PP in terms of its flame-retardant properties thermal stability. (C) 2014 Wiley Periodicals, Inc.