TITLE:
Influence of Organoclay Structure on Nanostructured Materials Based on Eva
AUTHORS:
Gisele C. V. Iulianelli, Pedro José Oliveira Sebastião, Maria Inês B. Tavares, Fernanda Abbate dos Santos
KEYWORDS:
EVA, Nanocomposites, NMR, Relaxometry
JOURNAL NAME:
Materials Sciences and Applications,
Vol.6 No.10,
October
16,
2015
ABSTRACT: This article reports the preparation of a series of EVA nanocomposites employing solution casting methods using different types of organo-modified montmorillonite clay. The effect of the organoclay type on the structural organization and thermal behavior of EVA nanostructured materials were systematically investigated. Regarding thermal behavior, the thermogravimetric analysis showed that the nanocomposites presented a slight decrease in thermal degradation temperature compared to EVA, while differential scanning calorimetry, in general, did not show a significant change in the thermal transition temperatures such as glass transition, melting temperature and crystallization temperature of the nanocomposites, regardless of the type and proportion of organoclay in the systems. With respect to structural aspect, the X-ray diffractograms showed that all systems presented a heterogeneous distribution of the nanoparticles, containing part intercalated. Nuclear magnetic resonance relaxometry data provided complementary information for the X-ray results, showing that the EVA systems containing 5 wt% of both studied organoclays presented a mixture of intercalated and exfoliated structures, evidencing that there was a surface interaction between polymer chains and clay lamellae.