Phase behavior of ionic microgels.
نویسندگان
چکیده
We employ effective interaction potentials between spherical polyelectrolyte microgels in order to investigate theoretically the structure, thermodynamics, and phase behavior of ionic microgel solutions. Combining a genetic algorithm with accurate free energy calculations we are able to perform an unrestricted search of candidate crystal structures. Hexagonal, body-centered orthogonal, and trigonal crystals are found to be stable at high concentrations and charges of the microgels, accompanied by reentrant melting behavior and fluid-fcc-bcc transitions below the overlap concentration.
منابع مشابه
Impact of single-particle compressibility on the fluid-solid phase transition for ionic microgel suspensions.
We study ionic microgel suspensions composed of swollen particles for various single-particle stiffnesses. We measure the osmotic pressure π of these suspensions and show that it is dominated by the contribution of free ions in solution. As this ionic osmotic pressure depends on the volume fraction of the suspension ϕ, we can determine ϕ from π, even at volume fractions so high that the microge...
متن کاملElectric field driven self-assembly of ionic microgels
We study, using fluorescent confocal laser scanning microscopy, the directed self-assembly of cross-linked ionic microgels under the influence of an applied alternating electric field at different effective packing fractions feff in real space. We present a detailed description of the contribution of the electric field to the soft interparticle potential, and its influence on the phase diagram ...
متن کاملI. Synthesis and Swelling Behavior of Pnipam Co Amp Micro- Gel Colloids
Ionic PNIPAm microgels were synthesized by free-radical precipitation polymerization using 2-acrylamido-2-methyl-1-propanesulfonic acid as an ionic co-monomer (references 7 and 9 of the paper), and fluorescently labelled with the covalently linked dye methacryloxyethyl thiocarbamoyl rhodamine B. N, N-methylene-bis-acrylamide was used as a cross-linker (with a 2.74 mol% cross-link density) and p...
متن کاملVolume phase transition mechanism of poly[oligo(ethylene glycol)methacrylate] based thermo-responsive microgels with poly(ionic liquid) cross-linkers.
Thermo-dynamic volume phase transition mechanisms of poly[oligo(ethylene glycol)methacrylate] (POEGMA) based microgels with poly(ionic liquid) (PIL) cross-linking moieties are investigated in detail on the basis of temperature-dependent Fourier transform infrared (FTIR) spectroscopy. The original FTIR data are further analysed by two-dimensional correlation spectroscopy (2Dcos) with the perturb...
متن کاملEquilibrium properties of charged microgels: a Poisson-Boltzmann-Flory approach.
The equilibrium properties of ionic microgels are investigated using a combination of the Poisson-Boltzmann and Flory theories. Swelling behavior, density profiles, and effective charges are all calculated in a self-consistent way. Special attention is given to the effects of salinity on these quantities. In accordance with the traditional ideal Donnan equilibrium theory, it is found that the e...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 92 6 شماره
صفحات -
تاریخ انتشار 2004