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Poly(vinyl chloride) (PVC)/layered double hydroxide (LDH) composites and PVC/poly(methyl methacrylate) (PMMA)/LDH composites were prepared via solution intercalation into PVC using both unmodified and organo-modified LDHs and variable-molecular-weight PMMA as additional components. The LDH dispersion was investigated using X-ray diffraction analysis and electron microscopy in scanning and transmission modes. Spotlight fourier transform infrared (FTIR) chemical imaging analysis was also used to obtain a deeper insight into the dispersion of polymer phases and LDH segregation. Thermal properties were determined using thermogravimetric analysis and differential scanning calorimetry; moreover, a preliminary investigation of mechanical properties in tensile mode and evaluation of the Vicat softening temperature were carried out. The morphological analysis of PVC/LDH and PVC/PMMA/LDH composites evidenced in both cases the presence of disordered micro-aggregates with loss of the LDH crystallographic symmetry depending on the amount and molecular weight of PMMA. In particular, in the case of PVC/PMMA/LDH composites, the FTIR imaging analysis showed that PMMA mostly segregated in the LDH phase. However, even if the degree of LDH dispersion was not elevated (micro-aggregates with disordered structures and size ranging from 0.5 up to 11 µm were evidenced), thermal stability and mechanical properties of the composites were improved with a synergic effect of PMMA and LDH. © 2013 Society of Chemical Industry

Coating materials characterised by intrinsic inhomogeneity or nanostructured morphology can display unique interfacial (e.g. surface and adhesion) and bulk (e.g. mechanical, thermal) properties, when heterophasic or self-segregating components are obtained by suitable design of the constitutive copolymers' structure. With the purpose of obtaining intrinsically photostable low-surface energy coating materials characterised by good penetration into porous substrates and variable response of the adhesive and polymer-air interface, fluorinated acrylic-based copolymers and water-borne acrylic-organosilane hybrids have been considered. For the latter, dispersed phase polymerisation procedures based on combined emulsion copolymerisation and hydrolysis-polycondensation of organosilane precursors have been adopted.