Artículos de revistas
Clay Platelet Partition within Polymer Blend Nanocomposite Films by EFTEM
Registro en:
Acs Applied Materials & Interfaces. Amer Chemical Soc, v. 2, n. 12, n. 3648, n. 3653, 2010.
1944-8244
WOS:000285449300036
10.1021/am100812m
Autor
Linares, EM
Rippel, MM
Galembeck, F
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Transmission electron microscopy (TEM) is the main technique used to investigate the spatial distribution of clay platelets in polymer nanocomposites but it has not often been successfully used in polymer blend nanocomposites because the high contrast between polymer phases impairs the observation of clay platelets. This work shows that electron spectral imaging in energy filtered TEM (EFTEM) in the low-energy-loss spectral crossover region allows the observation of platelets on a clear background. Separate polymer domains are discerned by imaging at different energy losses, above and below the crossover energy, revealing the material morpholgy. Three blends (natural rubber [NR]/poly(styrene-butyl acrylate) [P(S-BA)] [P(S-BA)]/poly(vinyl chloride) [PVC] and NR/starch) were studied in this work, showing low contrast between the polymer phases in the 40-60 eV range in the NR/P(S-BA) and P(S-BA)/PVC blend nanocomposites, the clay platelets accumulate in the P(S-BA) phase, while in the P(S-BA)/PVC nanocomposites and clay is also found at the interfaces. In the NR/starch blend, clay concentrates at the interface but it also penetrates the two polymer phases. These observations reveal that nanostructured soft materials can display complex morphochemical patterns that are discerned thanks to the ability of EFTEM to produce many contrast patterns for the same sample. 2 12 3648 3653 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)