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Polyamides belong to the major class of engineering polymers with very attractive properties but fail in a brittle manner under stress concentrators. PA6/ABS blends are well-established commercial materials due to their stiffness/toughness balance even when stress concentrators are present. The pair PA6/ABS is immiscible and exhibits poor mechanical properties due to unfavorable interactions, thus, an efficient compatibilization is mandatory for practical applications. Deep understanding of the processing-structure-properties interplays requires multiple characterization techniques to provide insights on the impact of the processing/compatibilization on morphology and phases' distribution. In this work an advanced co-localized AFM-Raman strategy was used to study the compatibilization of PA6/ABS blends with SAN-g-Maleic Anhydride. AFM and TEM allowed nanomechanical analysis and characterization of the blends' morphologies. Co-localized AFM-Raman provided new fundamental insights on the compatibilizer's effect on the PA6's γ polymorphic crystallization. The amount and distribution of this γ phase were found to depend on the blending protocol.

Proton-Exchange Membrane Fuel Cells is a promising emission free energy technology. New generation of hybrid membrane for hydrogen fuel cells were produced from commercial sPEEK membranes, chemically and mechanically stabilized with a Sol-Gel (SG) phase. To study the process-structure-properties relationship of our alternative membranes we coupled Atomic Force Microscopy and Raman microspectroscopy on membranes prepared by cryo-ultramicrotomy without epoxy embedding. This paper demonstrates the powerfulness of co-localized AFM-Raman analysis, revealing the inner structure of hybrid membranes. We obtained quantitative data on the diffusion/condensation of SG precursors inside the sPEEK membrane. Co-localized analyses revealed the formation of skin layers with lower SG concentration on both sides of the membrane. The diffusion of species from the SG phase at the cross-section surface was observed at the first step of fabrication (insufficient SG condensation) and disappeared after hydrothermal treatments (improved SG condensation). The nano-mechanical data revealed a densification of the SG phase through the fabrication process.

Morphologies of ultrathin films (10–60 nm) of miscible poly(e-caprolactone)/poly(vinyl chloride) (PCL/PVC) blends have been investigated under isothermal crystallization conditions by real time atomic force microscopy, and electron diffraction techniques. It was found that the morphology and growth rate of PCL/PVC blends strongly depend on the blend composition, crystallization temperature and film thickness. At a film thickness of 30 nm, the truncated lozenge-shape morphology of pure PCL crystals, found when the growth rate is slow, bent with increasing PVC content to form S-shaped or inverted S-shaped crystals, the curvature increasing by lowering the crystallization temperature. Electron diffraction patterns reveal that these crystals are flat-on single crystals with the PCL molecular chains (c axis) in the blends slightly tilted with respect to the lamella normal, while the b direction of the crystal lattice, corresponding to the fast growing direction of the growth front, follows a S line. Upon decreasing the film thickness (

The influence of minute amounts of residual tetrahydrofuran on the crystallization of ultrathin poly(e-caprolactone) (PCL) films has been investigated in real-time by atomic force microscopy. Crystallizations were performed at 30 °C, after melting at 64 °C, for different periods of time; both the morphology and growth rate of the crystals were found to depend on the thermal history of the sample, i.e. on the heating time, due to the evaporation of the residual solvent trapped in the spin-coated polymer. The residual solvent, acting as a plasticizer, facilitates the diffusion of the polymer chains to the crystal growth front; its elimination slows down the growth rates and leads to a decrease of the width of the dendrites. Growth rates were measured for the edge-on and for the flat-on lamellae, which are nucleated from them. Edge-on lamellae were found to crystallize 15 times faster than flat-on lamellae. Finally, spinodal dewetting was observed in the melt left between dendrites grown at 30 °C, after evaporation of the residual solvent, on a substrate of lower wettability. These observations are discussed in terms of the mobility of polymer chains in the melt.