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If two good solvents become poor for a polymer when mixed, the solvent pair is called a cononsolvent pair. The sharp reentrant coil-to-globule-to-coil transition of a poly(N-isopropylacrylamide) chain observed in the mixed solvent of water and methanol is shown to be caused by the competitive hydrogen bonding by water and methanol molecules onto the polymer(More)
This paper proposes a simple model of transient networks of telechelic associating polymers for molecular simulations and reports the main results obtained by molecular dynamics on the rheological properties of the transient networks. The steady shear viscosity obtained by the non-equilibrium molecular dynamics simulation exhibits shear thickening at(More)
The collapse of a poly(N-isopropylacrylamide) (PNIPAM) chain upon heating and the phase diagrams of aqueous PNIPAM solutions with a very flat lower critical solution temperature (LCST) phase separation line are theoretically studied on the basis of cooperative dehydration (simultaneous dissociation of bound water molecules in a group of correlated(More)
The nonaffine transient network theory is used to study the time development of the shear and normal stresses under start-up shear flows in networks formed by self-assembled telechelic, hydrophobically modified water-soluble polymers. The initial slope, strain hardening, and overshoot of the shear stress are studied in detail in relation to the nonlinear(More)
This paper proposes simple models of polymer networks with sliding junctions for molecular simulation and reports the main results obtained by Brownian dynamics on the elastic properties of networks with tri-functional sliding junctions. The stress-strain relation for isotropic swelling and uniaxial deformation are obtained and compared with those of the(More)
A statistical-mechanical theory of thermoreversible gelation considering loops for the system consisting of bifunctional polymer units carrying A functional groups and trifunctional units carrying B functional groups at their ends is constructed. We obtain the sol-gel transition line and the properties of the post-gel region as functions of the polymer(More)
We examine the spatial distribution of fluorescent-labeled charged polystyrene (PS) particles (particle volume fraction ϕ = 0.0001 and 0.001, diameter d = 183 and 333 nm) added to colloidal crystals of charged silica particles (ϕ = ϕ(s) = 0.035-0.05, d = 118 nm). At ϕ(s) = 0.05, the PS particles were almost randomly distributed in the volume-filling(More)
The formation of intramolecular micelles in copolymers with periodic sequence, where hydrophobic units (stickers) are periodically placed along the chain, is studied by using multicanonical Monte Carlo computer simulations for an off-lattice bead-rod model in three dimensions. With decreasing the temperature, a transition from random-coil conformations to(More)
High-density optical disc recorders using the blue-violet diode laser have been recently released and it is expected that Blu-ray Disc (BD) drives emerge in the PC market. We adopted in-house integrated modules of hybrid type that enable us to make mechanical parts and optical components thinner and compact. As a result, we have developed an optical pickup(More)
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