US EPA

3857438 

Journal Article 

Layered perovskite nanosheets bearing fluoroalkoxy groups: their preparation and application in epoxy-based hybrids 

Asai, Y; Ariake, Y; Saito, H; Idota, N; Matsukawa, K; Nishino, T; Sugahara, Y 

2014 

1 

RSC Advances
EISSN: 2046-2069 

4 

51 

26932-26939 

10.1039/c4ra01777c 

WOS:000338640200050 

Nanosheets bearing CF3(CF2)(7)C2H4O groups on their surface were prepared from a CF3(CF2) 7C2H4O derivative of ion-exchangeable layered perovskite HLaNb2O7 center dot xH(2)O (HLaNb) via exfoliation, and were further utilized to prepare epoxy-based hybrids. The CF3(CF2)(7)C2H4O derivative of HLaNb (C10F_HLaNb) was prepared by reacting the n-decoxy derivative of HLaNb with 1H,1H,2H,2H-perfluorodecanol, CF3(CF2)(7)C2H4OH. TEM and AFM observations revealed that the C10F_HLaNb was exfoliated into individual nanosheets bearing surfaces covered with CF3(CF2)(7)C2H4O groups after ultrasonication in acetonitrile. The nanosheet dispersion in acetonitrile was employed to prepare epoxy-based hybrids, and the FE-TEM image of the epoxy-based hybrid with 5 mass% of the nanosheets (C10F_HLaNb/epoxy_5) showed that the nanosheets were dispersed in the epoxy matrix. Thermogravimetry of C10F_HLaNb/epoxy_5 and neat epoxy resin indicated that the initial mass loss due to water decreased and the thermal decomposition retarded by introducing C10F_HLaNb nanosheets. Dynamic mechanical thermal analysis revealed that the glass transition temperature of C10F_HLaNb/epoxy_5 (161 degrees C) was higher than that of neat epoxy resin (110 degrees C). These results clearly exhibit that thermal properties were improved by incorporating nanosheets bearing hydrophobic CF3(CF2) 7C2H4O groups in the epoxy resin most likely due to a decrease in water content. A water uptake test demonstrated that the water uptake rate of C10F_HLaNb/epoxy_5 was lower than that of the neat epoxy.