Preparation and characterization of a polycaprolactone/C 60 composite and its improved counterpart (PCLNH 2 /C 60 OH)

In this study, polycaprolactone/C 60 (PCL/C 60 ) hybrids were prepared via a melt‐blending method. To enhance the compatibility between PCL and C 60 , the acrylic acid‐grafted polycaprolactone (PCL‐ g ‐AA) was first transformed to PCLNH 2 by mixing with 1,6‐diaminohexane, while C 60 was oxidized using a mixture of H 2 SO 4 /HNO 3 and NaOH to derive C 60 fullerol (C 60 OH). Thereafter, C 60 OH and PCLNH 2 were used to replace PCL and C 60 , respectively. The resulting products were characterized using FTIR, solid‐state 13 C‐ and 1 H‐ NMR, TGA, DMA, SEM, TEM, and Instron mechanical testing. Because of the formation of NHCO groups through the reaction between amino groups of PCLNH 2 and hydroxyl groups of C 60 OH, thermal and mechanical properties of the PCLNH 2 /C 60 OH composite were significantly superior to those of PCL/C 60 . The optimal blend was the 5 wt % C 60 OH with PCLNH 2 , producing an 84°C increase in initial decomposition temperature (IDT). C 60 OH in excess of 5 wt % aggregated and caused separation of the organic and inorganic phases, lowering their compatibility.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010