Inter-diffusion between PMMA and PVDF during lamination studied by time-of-flight secondary ion mass spectrometry chemical imaging

A laminate was prepared by laminating a poly(vinylidene fluoride) (PVDF) disc and a poly(methyl methacrylate) (PMMA) disc using compression moulding. Both PVDF and PMMA are miscible polymers. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) chemical images were used to investigate inter-diffusion between the PVDF and PMMA during lamination at 200 °C and 16 MPa. Negative ToF-SIMS chemical images clearly revealed the presence of inter-diffusion between the PVDF and PMMA. Both the lamination time and the PMMA molecular weight could significantly influence the inter-diffusion distance. As the lamination time increased, the inter-diffusion distance increased significantly. In addition, as the PMMA molecular weight decreased, the inter-diffusion distances also increased markedly due to the decrease in viscosity of the PMMA.