Fully exfoliated PS/clay nanocomposites were prepared via FRP in dispersion. Na‐MMT clay was pre‐modified using MPTMS before being used in a dispersion polymerization process. The objective of this study was to determine the impact of the clay concentrations on the monomer conversion, the polymer molecular weight, and the morphology and thermal stability of the nanocomposites prepared via dispersion polymerization. DLS and SEM revealed that the particle size decreased and became more uniformly distributed with increasing clay loading. XRD and TEM revealed that nanocomposites at low clay loading yielded exfoliated structures, while intercalated structures were obtained at higher clay loading.
Summary: Vinylester resin matrix composites were fabricated with 1, 3, 5 and 10 wt.‐% loadings of organoclay. The composite samples were subjected to various characterization techniques like X‐ray diffraction, flexural testing, dynamic mechanical analysis, thermogravimetric analysis, and scanning electron microscopy. The clay samples as well as the clay–resin composites were investigated by X‐ray diffraction. From the shift in the peak positions and the change in d‐spacing values, it was evident that there was intercalation in the 10 wt.‐% composites, whereas exfoliation occurred in the 1, 3, and 5 wt.‐% composites. The flexural strength and the breaking energy of all the composites were decreased compared with the unfilled resin, but there was an increase in flexural modulus value by 13%. From the dynamic mechanical analysis of the 3 and the 5 wt.‐% composites, it was observed that the loss modulus value was higher in the 3 wt.‐% composites, but the glass transition temperature was slightly higher in the 5 wt.‐% composites. Thermal degradation behavior was also improved in the 5 wt.‐% composites compared with the 3 wt.‐% composites.
Fracture surface of 3 wt.‐% clay filled vinylester resin matrix composite in different magnifications. 相似文献
The preparation of new rubber based nanocomposites by using properly modified organophilic clays is described. A commercial organophilic montmorillonite containing a hydroxylated ammonium ion is reacted with LPBs. The reaction causes a decrease of the polarity of the clay and a great increase of the interlayer distance. The modified organoclays are successfully dispersed into rubber matrices (SBR or BR) by melt blending in an internal batch mixer. SAXS analyses and TEM micrographs revealed the formation of highly exfoliated nanocomposites containing intercalated stacks made of few lamellae.
