Facile preparation of bimodal polyethylene with tunable molecular weight distribution from ethylene polymerization catalyzed by binary catalytic system in the presence of diethyl zinc

A series of novel honeycomb films of tri- and octa-arm polystyrene-b-poly(tert-butyl acrylate) star polymers prepared by atom transfer radical polymerization and nitroxide mediated radical polymerization, respectively, have been fabricated. The type of solvents, specifically their miscibility in water is one of essential parameters to construct ordered pore structures. The tri- and octa-arm star polymers yield well-ordered microporous film specifically in 10 to 30 g/L CHCl₃ solution. The contact angle of glass slide substrate (54.57°) is adjusted to 41.06° by plasma treatment and to 12.21° by coating the glass slide with highly hydrophilic hyperbranched polyglycidol. The ordered honeycomb films are created on the hydrophobic substrates, but the ordered films are not formed on the hydrophilic substrates. Microspheres with the diameters ranging from hundreds of nanometers to several micrometers are also obtained by a slight modification of breath figure method.