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The crystallization behavior of poly(ethylene adipate) (PEA) on highly oriented high-density polyethylene (PE) substrate both from solution and isotropic melt was studied by means of optical microscopy, differential scanning calorimetry, atomic force microscopy and electron diffraction. The results show that the PE influences the crystallization of PEA strongly, which results in an epitaxial growth of PEA with well ordered structure. At the boundary of the PE substrate, a transcrystalline PEA layer is observed. Fine structural observation illustrates that the PEA grows on the PE substrate in edgeon lamellae with fixed orientation. Electron diffraction demonstrates that the epitaxial organization of PEA on PE occurs with both polymer chains parallel, which leads to the (00 l) PEA diffractions inclined ±23.5° to the chain direction of PE crystals. Combining the real space morphological observation and electron diffraction results, it is concluded that the epitaxial PEA edge-on lamellae are folded in the {00 l} lattice planes. [ABSTRACT FROM AUTHOR]

The specular and off-specular X-ray reflectivities were efficiently employed to study the evolution of surface morphology as a function of temperature in a single layer of poly(3-hydroxybutyrate) (PHB) and a bilayer of PHB/poly(vinyl phenol) (PVPh) on Si substrates. The results indicate that the changes of thickness and surface roughness caused by pre-melting of PHB crystals are not obvious for the single layer, whereas the surface roughness of the PHB layer and the intensity of the off-specular X-ray reflectivity for the bilayer exhibit a remarkable non-monotonic change in the temperature range of 100-150°C; the roughness parameter evaluated by the specular X-ray reflectivity reaches its maximum at 120°C. The interaction at the interface between PVPh and PHB certainly contributes to the non-monotonic changes. Such interaction also affects the crystallization and melting behavior of PHB thin film greatly. The crystallization of PHB thin film is inhibited even on the glassy surface of PVPh sublayer. In the melting process, the PHB crystals on PVPh sublayer feature a three-section melting curve separated by a plateau region of 120-140°C. [ABSTRACT FROM AUTHOR]