An approach using CF4/CH4 plasma-induced surface modification to impart flame retardancy to polypropylene

The flammability of PP film treated with CF4/Ch(4) plasma was partially increased compared with that of untreated PP. In PP film, pretreated with CH4 plasma to deposit a barrier layer and then with CF4/CH4 plasma, the flame retardancy was improved. The surface flame retardancy of surface crosslinking by CH4 plasma was confirmed by the burning rate and TGA analysis. According to the change in burning rate over the entire range of %CF4 in the CF4/CH4 mixture, the whole range could be divided into three regions. The regions are distinguished by their mechanistic aspects of flame retardancy, which is due to the different mechanistic aspects of PP surfaces exposed to CF4/CH4 plasmas.