A unique class of aromatic ether polymers containing perfluorocyclopentenyl (PFCP) enchainment was prepared from the simple step growth polycondensation of commercial bisphenols and octafluorocyclopentene (OFCP) in the presence of triethylamine. Model studies indicate that the second addition/elimination on OFCP is fast and polycondensation results in linear homopolymers and copolymers without side products. The synthesis of bis(heptafluorocyclopentenyl) aryl ether monomers and their condensation with bisphenols further led to PFCP copolymers with alternating structures. This new class of semifluorinated polymers exhibit surprisingly high crystallinity in some cases and excellent thermal stability.
A series of new segmented semifluorinated polyaryl ethers (PAEs) containing a biphenyl segmented by semifluorinated oligoethylene (SFE) units were prepared by nucleophilic addition of a commercial oligo(ethylene glycol)s to 4,4 0 -bis(4-trifluorovinyloxy)biphenyl. These new thermoplastics were characterized by 1 H and F 19 nuclear magnetic resonance (NMR) and attenuated total reflectance Fourier transform infrared (ATR-FTIR). Gel permeation chromatography (GPC) analysis displayed number average molecular weights (M n s) from 9000 to 13,000. Thermal properties of the polymers were studied by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). DSC chromatograms displayed glass transition temperatures (T g s) from 11 to 1 C. The onsets of degradations were observed by TGA analysis between 313 to 333 C in air and 326 to 363 C in nitrogen, respectively. A second onset of degradation was observed from 452 to 470 C for all polymers. In addition, crystalline morphologies were studied by tapping mode atomic force microscopy (TM-AFM) and showed needle-like crystallites.
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