A process for polymerizing vinyl phosphonic acid with C6F13I perfluoroalkyl iodide chain-transfer agent

The synthesis of oligomeric VPA structures via the CTA perfluorohexyl iodide has been investigated. NMR and MALDI-TOF MS analysis showed that the structures were produced exclusively by radical-transfer reactions. The oligomers had a molecular weight above 2000 g.mol(-1) and exhibited intra- and intermolecular anhydrous bonding. The investigation showed that the reaction is not a living (controlled) system, but follows conventional radical telomerization. The value for the transfer constant for C6F13I to VPA was found to be 3.4 at 70 degrees C and 4.3 at 80 degrees C. This high value may be partially explained by a low k(p)(2)/k(t) ratio, which suggests a low k(p). The oligomeric structures showed a relatively high resistance to thermal degradation.