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Keywords:

  • amphiphilic;
  • crosslinking;
  • fluoropolymers;
  • hyperbranched;
  • networks;
  • surfaces

Abstract

Amphiphilic copolymer networks were prepared from hyperbranched fluoropolymer (HBFP*, Mn = 38 kDa, by atom transfer radical-self condensing vinyl copolymerization) and linear diamine-terminated poly(ethylene glycol) (DA-PEG, Mn = 1,630 Da). Model studies found that the crosslinking mechanism occurred at ambient temperature as a result of reaction between DA-PEG and the benzylic chlorides of HBFP*. These networks underwent covalent attachment to glass microscope slides derivatized with 3-aminopropyltriethoxysilane, whereupon gel percent studies at various weight percentages of DA-PEG to HBFP* found that curing could be achieved at lower temperatures and shortened time periods relative to the previously reported parent HBFP–PEG system. Thermogravimetric analysis revealed that the crosslinked materials gave no evident mass loss up to 250 °C. Differential scanning calorimetry of the complex amphiphilic networks showed a suppressed glass transition temperature, relative to that observed for neat HBFP*, and multiple melting DA-PEG endotherm(s) near 30 °C. The films possessed a topographically-complex surface with features that increased in tandem with an increase in the ratio of DA-PEG to HBFP*, as detected by atomic force microscopy and quantified by increased rms roughness values. Internal reflection infrared imaging revealed a heterogeneous surface composition and confirmed that the domain sizes increased as the weight percent of DA-PEG increased. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4782–4794, 2006