Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB)/modified montmorillonite (EMMT) bio-nanocomposites were prepared via melt intercalation method. The thermal stability of the bio-nanocomposites was investigated. The results showed that the decomposition temperature (T5%) of P34HB/EMMT bio-nanocomposite reached 271.4°C, 39.9°C higher than that of pure P34HB. The remarkable thermal stability enhancement was presumably originated from the uniform dispersion of EMMT in the matrix and intercalated structures of P34HB/EMMT bio-nanocomposites, which was related to the increased compatibility of EMMT and P34HB caused by the ester group in EMMT. TGA-FTIR analysis on the thermal degradation procedures of the bio-nanocomposites manifested that the introduction of EMMT did not alter the degradation mechanism of P34HB. However, the intercalated structures hindered the mobility of P34HB macromolecular and slowed down the decomposing process of P34HB. POLYM. COMPOS., 38:673–681, 2017. © 2015 Society of Plastics Engineers

Hydrogenated nitrile rubber (HNBR)/organoclay nanocomposites (HNBR/OCNs) were prepared by mechanical mixing technique. By altering the temperature, pressure, and treatment time, respectively, the microstructural changes of HNBR/OCNs compounds under those treatments were studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM) in detail. It was investigated that after the treatment, the exfoliated organoclay dispersion in untreated HNBR/organoclay compounds transformed into the co-existing of exfoliated, intercalated, and aggregated structures by de-intercalation action. Moreover, pressure, and temperature played accelerated roles in determining the final clay structures in HNBR/OCNs. It was suggested that the transformation was caused by the relaxation of HNBR chains, and it could be proceed spontaneously in thermodynamics under the treatment condition.