De Goede E., Mallon P.E., Rode K., Pasch H.
Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa; German Institute for Polymers, Schlossgartenstr.6, 64289 Darmstadt, Germany
De Goede, E., Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa; Mallon, P.E., Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa; Rode, K., German Institute for Polymers, Schlossgartenstr.6, 64289 Darmstadt, Germany; Pasch, H., Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
The spatial degradation in impact PP copolymers with different ethylene contents is studied by FTIR microscopy and layer-by-layer milling of the sample surfaces, followed by ATR-FTIR, SEC, and CRYSTAF analysis. FTIR allows for tracking of the rate of degradation, providing information on the depth profiling of the degradation. Results show that samples with lower ethylene content degrade faster at all depths than those with higher ethylene content. The latter show a more uniform degradation from the surface to the bulk of the material at longer degradation times. This is ascribed to the higher amorphous content which results in a larger oxygen diffusion to the centre of the material while its slower rate of degradation is ascribed to the lower tertiary carbon content. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Amorphous content; ATR FTIR; Carbon content; FTIR; FTIR microscopy; impact PP copolymers; Layer-by-layers; Lower Tertiary; Oxygen diffusion; Poly(propylene) copolymers; Sample surface; Spatial degradation; Spatial heterogeneity; Thermo-oxidative degradation; Amorphous carbon; Copolymerization; Copolymers; Depth profiling; Ethylene; Gel permeation chromatography; Polypropylenes; Propylene; Degradation