FLUORINE CONTAINING DENDRIMERS & HYPERBRANCHED MACROMOLECULES

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Fluorine-containing dendritic and hyperbranched macromolecules are being designed and synthesized specifically to evaluate 1) their micromechanical properties; 2) the reactivities of the chain end groups, and; 3) the location and mobility of the chain ends. The synthesis of the hyperbranched fluoropolymers involves nucleophilic aromatic substitution facilitated condensation polymerization of A2B monomers, where A is a pentafluorophenyl group and B is a benzylic alcohol. Intermolecular reactions produce polymeric materials, whereas intramolecular reactions are responsible for macrocycle formation within the hyperbranched polymer structure and termination of the unique B functional group. MALDI-TOF mass spectrometry was employed to evaluate and quantify the extent of cyclization by observation of the acyclic and cyclic product peaks, differing in m/z units by 20 units due to the loss of HF upon cycle formation. The extent of cyclization at each degree of polyme riz ation was individually identifiable. Preparation of linear polymer analogs to the hyperbranched fluoropolymers is now underway and again, characterization of the molecular weights and extent of macrocycle formation will be made by MALDI-TOF.