Functional Hyperbranched Polymers Using Ring-Opening Metathesis Polymerization of Dicyclopentadiene with Monoterpenes
journal contributionposted on 10.03.2009, 00:00 by Robert T. Mathers, Krishnan Damodaran, Matthew G. Rendos, Michael S. Lavrich
A general method for the synthesis of hyperbranched functional polymers in monoterpenes is described. During the polymerization of dicyclopentadiene, metathesis reactions between the growing polymer chain and monoterpenes produced soluble well-defined polymers. The molecular weight, intrinsic viscosity [η], and glass transition temperature (Tg) values resulting from chain transfer to monoterpenes depended on the mode of monomer addition but generally decreased as follows: d-limonene > limonene oxide > β-pinene. Calculation of the Mark−Houwink−Sakarada values by gel permeation chromatography suggested that, in solution, the branched poly(dicyclopentadiene) had a smaller hydrodynamic volume than polynorbornene. Characterization by NMR spectroscopy indicated the hyperbranched polymer had a complex structure composed of linear, terminal, semidendritic, and dendritic units.