An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Frederick R. Phelan Jr., Nicos Martys, Charles C. Han
Lattice Boltzmann simulations have been carried out for two-phase systems in homogeneous shear flow at supercritical Capillary numbers and a viscosity ratio of unity. The simulations predict a three-stage mechanism for drop breakup. In the first stage, the
Characterization techniques for polymers have been discussed in literature. Normally these techniques are categorized in terms of mechanical testing methods, thermal analysis, electron and optical microscopy, nmr techniques, chromatographic methods
Kinetics of polymer phase separation has been briefly reviewed. This is a section on this subject for Encyclopedia of Materials: Science and Technology. This section includes summary of sinodal decomposition, critical temperature shift under shear flow
G Kim, C L. Jackson, M Libera, R Stadler, Charles C. Han, F V. Gyldenfeldt, V Balsamo
Distinctive behaviors of PCL(polycaprolactone) in block copolymers are significant for various polymer applications such as low temperature adhesives, biocompatibilizer and pigments. Thus, there has been increasing interest in the morphologies of block
Erik K. Hobbie, Haonan Wang, H Jeon, H W. Kim, D Stout, Charles C. Han
Optical studies of viscoelastic emulsions under simple shear flow reveal long-range spatial correlation in the orientation of the deformed domains. As the volume fraction of droplets increases, the tilt angle between the direction of orientation and the
Sheng Lin-Gibson, H W. Kim, G Schmidt, Charles C. Han, Erik K. Hobbie
Abstract: The equilibrium structure and shear response of model polymer-clay nanocomposite gels are measured using X-ray scattering, light scattering, optical microscopy, and rheometry. The suspensions form physical gels via the bridging of neighboring
H Grull, Li Piin Sung, Alamgir Karim, Jack F. Douglas, Sushil K. Satija, Makoto Hayashi, H Jinnai, TT Hashimoto, Charles C. Han
We investigate the influence of temperature and confinement on surface segregation in thin films of deuterated polybutadiene and polyisoprene near the critical point for phase separation. Neutron reflectivity measurements show that polyisoprene enriches at
Li Piin Sung, Jack F. Douglas, Charles C. Han, Alamgir Karim
We show that the addition of a small concentration of a block copolymer surfactant to a thin phase separating blend film can suppress the pattern formation that occurs in the blend films without block copolymer. This effect is observed even at very low
Li Piin Sung, Jack F. Douglas, Charles C. Han, Alamgir Karim
We show that the addition of a small concentration of a block copolymer surfactant to a thin phase separating blend film can supppress the pattern formation that occurs in the blend films without block copolymer. This effect is obseved even at very low
Li Piin Sung, Alamgir Karim, Jack F. Douglas, Charles C. Han
Phase separation in thin films leads to the formation of surface patterns (holes, bumps, and bicontinuous surface features) which depend on the film composition. These features are interpreted to arise from surface tension variations within the film that
Erik K. Hobbie, Haonan Wang, H W. Kim, Charles C. Han, E A. Grulke, Jan Obrzut
We describe an optical metrology for measuring shear-induced structure and orientation in dilute dispersions of multiwalled carbon nanotubes. Small-angle polarized light scattering and optical microscopy are combined in situ to quantify the structural
Erik K. Hobbie, H Jeon, Haonan Wang, H W. Kim, D J. Stout, Charles C. Han
Light scattering and optical microscopy have been used to measure the morphology as a function of shear rate and composition in polymer blends with viscoelastic asymmetry in the melt components. The blends studied are immiscible mixtures of low-vinyl