scholarly journals Accessing the Frank-Kasper Phase of Block Copolymer in the Fuzzy Colloid Regime

Author(s):  
Hsin-Lung Chen ◽  
Babak Nouri ◽  
Chun-Yu Chen ◽  
Yu-Shan Huang ◽  
Bradley Mansel

Abstract The discovery of Frank-Kasper (FK) phase in block copolymer (bcp) has prompted the progress of the field of soft quasicrystals. In principle, the formation of FK phase from the supercooled liquid phase of the bcp micelles should involve the mass transport of constituent molecules to transform the unimodal distribution of micelle size into the multimodal distribution prescribed by the volume asymmetry of the Voronoi cells in the FK phase. Here we present a new regime in which the Laves C14 phase of bcp developed below the glass transition temperature of the micelle core, where the mass transport was inhibited by the immobile block chains forming the core. The bcp micelle comprising a glassy core and a soft corona resembles the fuzzy colloid and the strong van der Waals attraction between the cores directs their organization into C14 phase to minimize the interparticle interaction energy under the metastable condition.

2007 ◽  
Vol 119 ◽  
pp. 17-20
Author(s):  
Gil Pyo Kim ◽  
Seung Bum Yoon ◽  
Young Soo Jung ◽  
Jae Hoon Ahn ◽  
Sung Hyeon Baeck ◽  
...  

Nanoparticles (Au, Pt, Ru) supported on metal oxides (TiO2, Heteropoly Acid) were prepared by PS-PVP block copolymer encapsulation method. It was confirmed by XPS analysis that the oxidation state of metal is 0 after calcination, which indicates the complete removal of polymer. Synthesized catalysts were characterized by TEM, SEM-EDS, and UV-VIS spectroscopy and it was observed that synthesis and calcination conditions, and the interaction between nanoparticle and metal oxide affected significantly the particle size of metal on the surface of metal oxide. When two different metal precursors were diffused into the core of inversed micelles, nano alloy could be synthesized and the composition of nano alloy was controlled by varying the ratio between the two metal precursors.


2011 ◽  
Vol 239-242 ◽  
pp. 2711-2716
Author(s):  
Xue Qing Liu ◽  
Ji Yan Liu

6-arm star-shaped Poly (ε-caprolactone)-dextran (sPCL-dextran) was synthesized and characterized. The core of the star polymer is dipentaerythritol, the inner block in the arm is hydrophobic poly (ε-caprolactone) (PCL), and the outer block in the arm is hydrophilic dextran. The synthesis involves three steps: (1) The ring-opening polymerization of ε-caprolactone (CL) initiated by dipentaerythritol produces 6-arm star-shaped PCL (sPCL-OH). (2) The sPCL-OH reacts with acryloyl chloride to get star-shaped PCL with acrylate end group (sPCL-CH=CH2). (3) The amino ended dextran (dextran-NH2) is then attached to sPCL-CH=CH2 terminus by Micheal addition to form star-shaped sPCL-dextran. The architecture of products was characterized with 1H NMR, GPC and element analysis. Micellization of sPCL-dextran in aqueous solutions was investigated by DLS. The results showed that the micelle size (Rh) and size distribution are related to the concentration of the sPCL-dextran. Salt, pH value and temperature have no obvious influence on the Rh.


2010 ◽  
Vol 114 (32) ◽  
pp. 13471-13476 ◽  
Author(s):  
Caihua Ni ◽  
Geng Wu ◽  
Changping Zhu ◽  
Bolong Yao

2005 ◽  
Vol 38 (24) ◽  
pp. 9957-9962 ◽  
Author(s):  
Kozo Matsumoto ◽  
Tetsuo Hirabayashi ◽  
Tamotsu Harada ◽  
Hideki Matsuoka

2021 ◽  
Author(s):  
Seung-Ryong Kwon ◽  
Seol Baek ◽  
Paul W. Bohn

Potential-induced wetting and dewetting behaviors in pH-responsive block copolymer membranes are investigated to establish a promising mass transport control system for ultrasensitive sensing applications.


2015 ◽  
Vol 6 (4) ◽  
pp. 561-572 ◽  
Author(s):  
Tuba Erdogan ◽  
Cigdem Bilir ◽  
Elif Erdal Unveren ◽  
A. Levent Demirel ◽  
Umit Tunca

Novel multiarm star block copolymer ionomers containing hydrophobic fluorinated block at the periphery and partially sulfonated polystyrene block at the core with varying ion exchange capacities (IECs) were synthesized.


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