Preparation and characterization of a polycaprolactone/C₆₀ composite and its improved counterpart (PCLNH₂/C₆₀OH)

In this study, polycaprolactone/C₆₀ (PCL/C₆₀) hybrids were prepared via a melt-blending method. To enhance the compatibility between PCL and C₆₀, the acrylic acid-grafted polycaprolactone (PCL-g-AA) was first transformed to PCLNH₂ by mixing with 1,6-diaminohexane, while C₆₀ was oxidized using a mixture of H₂SO₄/HNO₃ and NaOH to derive C₆₀ fullerol (C₆₀OH). Thereafter, C₆₀OH and PCLNH₂ were used to replace PCL and C₆₀, respectively. The resulting products were characterized using FTIR, solid-state ¹³C- and ¹H- NMR, TGA, DMA, SEM, TEM, and Instron mechanical testing. Because of the formation of NHCO groups through the reaction between amino groups of PCLNH₂ and hydroxyl groups of C₆₀OH, thermal and mechanical properties of the PCLNH₂/C₆₀OH composite were significantly superior to those of PCL/C₆₀. The optimal blend was the 5 wt % C₆₀OH with PCLNH₂, producing an 84°C increase in initial decomposition temperature (IDT). C₆₀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