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Abstract
Poly(propyleneimine) [PPI‐(NH2) n ] and poly(amidoamine) [PAMAM‐(NH2) n ] dendrimers with n = 4, 8, 16, 32 and 64, have been functionalized with a semifluorinated carboxylic acid [CF3(CF2)7CH2CH2COOH] on the surface. The thermal and liquid crystal properties of the resulting ionic dendrimers have been studied by polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X‐ray diffraction (XRD). All dendrimers show a smectic A (SmA) mesophase, except that derived from the fifth generation of PPI, which displays a columnar mesophase. The mesomorphic behaviour of the dendrimers is attributed to the formation of ionic bonds and to the microsegregation of the dendritic branches and the fluorinated peripheral chains.
Acknowledgements
This work has been supported by the CICYT of Spain (MAT2003‐07806‐C01 and CTQ2006‐15611‐C02‐01), FEDER (EU), by the Ministerio de Educación y Ciencia (MEC) (Acción Integrada Hispano‐Francesa HF20030116) and by the Diputación General de Aragón. We also thank Dr. Joaquín. Barberá for his assistance with the XRD studies and Dr. Pilar Romero for her assistance with the CPMAS experiments. R.M.‐R. acknowledges a fellowship from MEC (Spain).