Synthesis and characterization of polyethylene-based ionomer nanocomposites

A solvent-free reaction of polyethylene-g-maleic anhydride with a tertiary amino alcohol is used to prepare an ammonium carboxylate polyampholyte (PE-g-PA), whose structure is characterized through spectroscopic comparisons to an appropriate model compound. The introduction of ionic functionality results in substantial increases in melt elasticity and viscosity, as well as a demonstrably improved ability to exfoliate onium ion-exchanged montmorillonite clay (NR4+-MM) and to disperse nanosilica (SiO2). Physical and rheological analysis of these nanocomposites suggest that in spite of its relatively small surface area and its capacity to engage only in ion–dipole interactions with PE-g-PA, nanosilica provides a better balance of viscoelastic and mechanical properties when compared with onium-ion exchanged montmorillonite.