The structures of the composite films were characterized by field emission scanning electron microscopy ( FESEM ), Fourier transform infrared spectroscopy ( FTIR ) and thermo gravimetric analysis ( TGA ). 采用场发射扫描电镜(FESEM)、红外光谱(FTIR)、热重分析(TGA)等方法对复合膜结构进行表征。