Effect of Temperature and Compatibilizer on Interfacial Tension of PE/PA-6 and PP/EVOH

Abstract

Abstract Interfacial tension measurements for polyethylene/polyamide-6 (PE/PA-6) and polypropylene/ethylene-vinyl alcohol copolymer (PP/EVOH) pairs were performed using the spinning drop method. The effects of the temperature and maleation content of the polyolefin on the interfacial tension were evaluated. The temperature coefficients of interfacial tension were found to be 0.036 and 0.087 dyne/cm/°C for the PE/PA-6 and maleated PP/EVOH systems, respectively. The interfacial tension of PE/PA-6 system showed exponential dependence on the maleation content of PE. The accuracy of the spinning drop method was evaluated against the pendant drop technique. It was found that the spinning drop technique tends to yield lower interfacial tension values than the pendant drop method. The harmonicmean equation was found to provide a fair estimate for the interfacial tension of PE/PA-6 pair.