Journal of Applied Polymer Science, Vol.103, No.1, 110-117, 2007
Preparation and applications of novel fluoroalkyl end-capped sulfonic acid oligomers-silica gel polymer hybrids
Fluoroalkyl end-capped 2-methacryloxyethanesulfonic acid homo-oligomer [R-F-(MES)(n)-R-F] and 2-methacryloxyethanesulfonic acid-N,N-dimethylacrylamide co-oligomers [R-F-(MES)(x)-(DMAA)(y)-R-F] reacted with tetraethoxysilane (TEOS) under acidic conditions to afford R-F(MES)(n)-R-F homo-oligomer-SiO2 polymer hybrid and R-F-(MES)(x)-(DMAA)y-R-F co-oligomer-SiO2 polymer hybrid, respectively. Thermogravimetric-mass spectra showed that the thermal stability of R-F-(MES)(n)-R-F homo-oligomer-SiO2 polymer hybrid was superior to that of traditionally well-known perfluorinated ion exchange polymers such as Nafion 112 (TR). The sol solutions of the fluorinated co-oligomer-SiO2 polymer hybrid were applied to the surface modification of glass to exhibit not only a strong oleophobicity imparted by fluorine but also a good hydrophilicity on the glass surface. On the other hand, R-F-(MES)(x)-(DMAA)(y)-R-F co-oligomer reacted with TEOS in the presence of a variety of silica nanoparticles (mean diameters: 11-95 nm) under alkaline conditions to afford fluoroalkyl end-capped oligomers-silica nanoparticles (mean diameters: 32-173 nm) with a good dispersibility and stability in methanol. Similarly, a variety of fluorinated oligomers containing sulfo groups-silica nanoparticles were prepared by the homo- and co-oligornerizations of fluoroalkanoyl peroxides with 2-methacryloxyethane sulfonic acid (MES) and comonomers such as N,N-dimethylacrylamide (DMAA) and acryloylmorpholine (ACMO) in the presence of silica nanoparticles. Interestingly, these isolated fluorinated particle powders were found to afford nanometer size-controlled colloidal particles with a good redispersibility and stability in aqueous and organic media such as methanol. These fluorinated nanoparticles containing sulfo groups were also applied to an excellent heterogeneous catalyst for Bronsted acid-catalyzed transformations. (C) 2006 Wiley Periodicals, Inc. J AppI Polym Sci 103: 110-117, 2007