CHARACTERIZATION OF A COATED INTERFACE BY FOURIER-TRANSFORM INFRARED MICROSPECTROSCOPY

A method for characterization of a polymer-polymer coated interface has been developed using Fourier transform infrared microspectroscopy. A cross section of a coated sample perpendicular to the film thickness was prepared with a microtome. The coated sample investigated was prepared by coating polypropylene/polyethylene-maleic anhydride-methyl acrylate copolymer/maleic anhydride graft ethylene-propylene rubber with a polyurethane layer. A mixed phase of the two polymers was detected at the interface region; this phase was approximately 160-mu-m in thickness. The coated sample was also prepared by coating polypropylene/ethylene-propylene rubber/talc with a polyurethane layer. A mixed phase of the two polymers was detected at the interface region; this phase was approximately 20-mu-m in thickness. The thickness of a mixed phase was dependent on the difference in the method of washing of the surfaces of the polypropylene blends.