Polymer, Vol.48, No.14, 3961-3973, 2007
Direct fluorination of various poly (p-phenylene): Effects of the polymer synthesis and thermal post-treatment
In order to complete a preliminary worl, about the direct fluorination of poly(p-phenylene) (PPP), the main parameters of the process were investivated. The molecular (chain length and crystallinity) and morphological effects (B.E.T. surface, granulometry) were studied. So, two new starting samples were studied in addition to. PPP synthesized by the Kovacic's method (i) a commercial PPP (Polysciences) and (ii) a pyrolyzed PPP, which is similar to an amorphous hydrogenated carbon. Moreover, an annealed PPP (Kovacic's synthesis and post-treatment at 400 degrees C for 36 h) was compared to the as-synthesized polymer. The reactions with F-2 gas differ significantly in accordance with the synthesis way and the post-treatment (annealing or pyrolysis). Investigations about the direct fluorination of PPPs were carried out for a better understanding of their behavior with respect to molecular fluorine. An extensive characterization was performed by complementary techniques (F-19 and C-13 NMR, FT-IR, and EPR). The fluorine content in the fluorinated PPPs is evaluated by these methods and a reaction mechanism is proposed. (c) 2007 Elsevier Ltd. All rights reserved.