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ABSTRACT Ternary block copolymer (BCP)‐homopolymer (HP) blends offer a simple method for tuning nanostructure sizes to meet application‐specific demands. Comprehensive dissipative particle dynamic (DPD) simulations were performed to study the impact of polymer interactions, molecular weight, and HP volume fraction (φHP) on symmetric ternary blend morphological stability and domain spacing. DPD reproduces key features of the experimental phase diagram, including lamellar domain swelling with increasingφHP, the formation of an asymmetric bicontinuous microemulsion at a critical HP concentration , and macrophase separation with further HP addition. Simulation results matched experimental values for and lamellar swelling as a function of HP to BCP chain length ratio,α = NHP/NBCP. Structural analysis of blends with fixedφHPbut varyingαconfirmed that ternary blends follow the wet/dry brush model of domain swelling with the miscibility of HPs and BCPs depending onα. Longer HPs concentrate in the center of domains, boosting their swelling efficiencies compared to shorter chains. These results advance our understanding of BCP‐HP blend phase behavior and demonstrate the value of DPD for studying polymeric blends. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys.2019,57, 794–803
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This content will become publicly available on February 24, 2026
Quaternary Ammonium‐Containing Polyelectrolyte Brush Particles for Removal of Perrhenate Anion From Water: Effect of N ‐Substituents
Abstract Radioactive pertechnetate (TcO4−) from the nuclear fuel cycle presents a severe risk to the environment due to its large solubility in water and non‐complexing nature. By utilizing the chaotropic properties of TcO4−and its nonradioactive surrogate perrhenate (ReO4−) and the principle of chaotropic interactions, a series of quaternary ammonium‐containing polyelectrolyte brush‐grafted silica particles are designed and applied to remove ReO4−from water. These cationic hairy particles (HPs) are synthesized by surface‐initiated atom transfer radical polymerization of 2‐(N,N‐dimethylamino)ethyl methacrylate and subsequent quaternization with various halogen compounds. Dynamic light scattering (DLS) studies showed that the HPs with sufficiently longN‐alkyl andN‐benzyl substituents underwent sharp size reduction transitions in water when titrated with a KReO4solution, indicating strong chaotropic interactions between the brushes and ReO4−. All the HPs exhibited fast adsorption kinetics; the HPs with longerN‐alkyl andN‐benzyl substituents showed higher capabilities of removing ReO4−than those with shorterN‐alkyls. Moreover, the brush particles with longerN‐substituents displayed a significantly stronger ability in selective adsorption of ReO4−than the particles with shorterN‐substituents in the presence of competing anions, such as F−, Cl−, NO3−, and SO42−. This work opens a new avenue to design high‐performance adsorbent materials for TcO4−and ReO4−.
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- PAR ID:
- 10576603
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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