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.