Grafted Nanoparticle Surface Wetting during Phase Separation in Polymer Nanocomposite Films

Phase-Separation-Induced Surface Patterns in Thin Polymer Blend Films

Atomic force microscopy (AFM), neutron reflection (NR) and secondary ion mass spectroscopy (SIMS) are used to examine phase separation in symmetrically segregating thin polymer blend films (e1000 Å). Phase separation in the film leads to undulations of the liquid-air interface, provided the film is sufficiently thin to suppress surface-directed spinodal decomposition waves. Flattened droplets a...

Equilibrating nanoparticle monolayers using wetting films.

Monolayers of bimodal gold nanoparticles on silicon are investigated by a combination of microscopy (dry monolayers) and x-ray diffraction (dry and wet monolayers). In the presence of an excess of small particles, the nanoscale packing structure closely resembles the small-particle-rich scenario of the structural crossover transition that has been predicted and also observed with micron-scale h...

Phase transformations in nanocomposite ZrAlN thin films during annealing

Phase separation of ultrathin polymer-blend films on patterned substrates

The phase separation of ultrathin polymer-blend films of polystyrene and polybutadiene on microcontact printed alkanethiol patterns with hydrophobic and hydrophilic end groups (2CH3 and 2COOH! is investigated by atomic force microscopy. Simulations suggest that the phase-separation morphology can be controlled through patterns that modulate the polymer-surface interaction, and this concept is v...

Antimicrobial graphene polymer (PVK-GO) nanocomposite films.

The first report on the fabrication and application of a nanocomposite containing poly-N-vinyl carbazole (PVK) polymer and graphene oxide (GO) as an antimicrobial film was demonstrated. The antimicrobial film was 90% more effective in preventing bacterial colonization relative to the unmodified surface. More importantly, the nanocomposite thin film showed higher bacterial toxicity than pure GO-...