Photodegradation Activity of Poly(ethylene oxide-b-ε-caprolactone)-Templated Mesoporous TiO2 Coated with Au and Pt

2020 ◽  
Vol 20 (8) ◽  
pp. 5276-5281 ◽  
Author(s):  
Wei-Cheng Chu ◽  
Jeonghun Kim ◽  
Minjun Kim ◽  
Abdulmohsen Ali Alshehri ◽  
Yousef Gamaan Alghamidi ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
Charge Carriers ◽  
Nanocomposite Films ◽  
Soft Template ◽  
X Ray Scattering ◽  
Evaporation Induced Self Assembly ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Mesoporous TiO2 films are synthesized through evaporation-induced self-assembly using poly(ethylene oxide-b-ε-caprolactone) diblock copolymers as a soft-template. Using small-angle X-ray scattering and scanning electron microscopy, we investigate the effect of the TiO2/PEO-b-PCL ratio on the resulting nanoarchitectonic structure. After sputter-coating Au and Pt layers, these Au/TiO2 and Pt/TiO2 nanocomposite films display drastically enhanced photodegradation of rhodamine 6G under ultraviolet irradiation, due to the metal films inhibiting the rapid recombination of photogenerated charge carriers.

Solvent-tuning of ordered mesoporous silicas prepared through evaporation-induced self-assembly templated by poly(ethylene oxide-b-ε-caprolactone)

RSC Advances ◽  
2014 ◽  
Vol 4 (105) ◽  
pp. 61012-61021 ◽  
Author(s):  
Wei-Cheng Chu ◽  
Chen-Xin Lin ◽  
Shiao-Wei Kuo
Keyword(s):  
Ethylene Oxide ◽  
Self Assembly ◽  
Mesoporous Silicas ◽  
Size Distributions ◽  
Ordered Mesoporous ◽  
Pore Size Distributions ◽  
Evaporation Induced Self Assembly ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Selection Of

Highly ordered mesoporous silicas having narrow pore size distributions and various morphologies merely through selection of an appropriate solvent.

scholarly journals Large and Giant Unilamellar Vesicle(s) Obtained by Self-Assembly of Poly(dimethylsiloxane)-b-poly(ethylene oxide) Diblock Copolymers, Membrane Properties and Preliminary Investigation of Their Ability to Form Hybrid Polymer/Lipid Vesicles

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2013 ◽  
Author(s):  
Martin Fauquignon ◽  
Emmanuel Ibarboure ◽  
Stéphane Carlotti ◽  
Annie Brûlet ◽  
Marc Schmutz ◽  
...  
Keyword(s):  
Light Scattering ◽  
Ethylene Oxide ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
Lipid Vesicles ◽  
Membrane Properties ◽  
Membrane Thickness ◽  
Hybrid Polymer ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

In the emerging field of hybrid polymer/lipid vesicles, relatively few copolymers have been evaluated regarding their ability to form these structures and the resulting membrane properties have been scarcely studied. Here, we present the synthesis and self-assembly in solution of poly(dimethylsiloxane)-block-poly(ethylene oxide) diblock copolymers (PDMS-b-PEO). A library of different PDMS-b-PEO diblock copolymers was synthesized using ring-opening polymerization of hexamethylcyclotrisiloxane (D3) and further coupling with PEO chains via click chemistry. Self-assembly of the copolymers in water was studied using Dynamic Light Scattering (DLS), Static Light Scattering (SLS), Small Angle Neutron Scattering (SANS), and Cryo-Transmission Electron Microscopy (Cryo-TEM). Giant polymersomes obtained by electroformation present high toughness compared to those obtained from triblock copolymer in previous studies, for similar membrane thickness. Interestingly, these copolymers can be associated to phospholipids to form Giant Hybrid Unilamellar Vesicles (GHUV); preliminary investigations of their mechanical properties show that tough hybrid vesicles can be obtained.

Mesoscopic simulation of the self-assembly of the weak polyelectrolyte poly(ethylene oxide)-block-poly(methyl methacrylate) diblock copolymers

Soft Matter ◽  
2015 ◽  
Vol 11 (22) ◽  
pp. 4366-4374 ◽  
Author(s):  
Dan Mu ◽  
Jian-Quan Li ◽  
Sheng-Yu Feng
Keyword(s):  
Ethylene Oxide ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
The Self ◽  
The Other ◽  
Mesoscopic Simulation ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
The Right ◽  
Weak Polyelectrolytes

We designed twelve types of weak polyelectrolytes (i.e., PEO-b-PMMA copolymers (BCP) in multi-arm structures, where six include EO blocks as joint points and the other six have MMA blocks as joint points). Of these, six are displayed; structures with EO blocks as joint points on the left, and those with MMA blocks as joint points on the right.

Formation Mechanism of Silica/Diblock Mesophases by Solvent Evaporation-Induced Self-Assembly

2001 ◽  
Vol 672 ◽  
Author(s):  
Kui Yu ◽  
Celeste A. Drewien ◽  
Alan J. Hurd ◽  
C. Jeffrey Brinker ◽  
Adi Eisenberg
Keyword(s):  
Self Assembly ◽  
Diblock Copolymers ◽  
Sol Gel ◽  
Homogeneous Solution ◽  
Solvent Evaporation ◽  
Present System ◽  
System A ◽  
Evaporation Induced Self Assembly ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

ABSTRACTIntermediate structures were trapped during the mesophase transition from lamellae to higher curvature structures in a sol-gel matrix. The target structures included normal hexagonally arranged cylinders and/or normal spheres in a cubic array distributed in a hydrophilic matrix. The present system is believed to be the first to trap these intermediates. Through solvent evaporation-induced self-assembly (EISA), mesostructured silica/diblock films with large characteristic length scales were prepared. The structure-directing agents were polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymers with high molecular weight, which are water insoluble and alcohol insoluble. We believe that no micellization took place in the present system; a disorder-to-order transition occurred due to the cooperative self- assembly of the diblock and silicates as the solvent preferentially evaporated from a film cast from a dilute homogeneous solution. During further preferential evaporation, the morphogenic effect of the increase of species concentration facilitates the mesophase development in the direction of a normal cubic to hexagonal to lamellar pathway. However, the morphogenic effects of both the decrease of the PS coil dimension and the siloxane condensation drive the mesophase development in opposite directions. The decrease of the PS coil dimension plays an important role in the present self-assembly process. Trapping of the intermediates and coexisting multiple mesophases are related to the facts that PS has high Tg and high hydrophobicity in particular, as well as to the fact that polymers have relatively low mobility in general.

scholarly journals Post-polymerization functionalization of poly(ethylene oxide)–poly(β-6-heptenolactone) diblock copolymers to tune properties and self-assembly

2017 ◽  
Vol 8 (3) ◽  
pp. 557-567 ◽  
Author(s):  
Brooke M. Raycraft ◽  
Jarret P. MacDonald ◽  
James T. McIntosh ◽  
Michael P. Shaver ◽  
Elizabeth R. Gillies
Keyword(s):  
Ethylene Oxide ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
Fluorescent Dyes ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Copolymers were synthesized and functionalized with a variety of moieties to tune self-assembly and install drugs or fluorescent dyes.

scholarly journals Crystallization and Morphology of Triple Crystalline Polyethylene-b-poly(ethylene oxide)-b-poly(ε-caprolactone) PE-b-PEO-b-PCL Triblock Terpolymers

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3133
Author(s):  
Eider Matxinandiarena ◽  
Agurtzane Múgica ◽  
Manuela Zubitur ◽  
Viko Ladelta ◽  
George Zapsas ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Diblock Copolymers ◽  
Crystallization Process ◽  
Scanning Calorimetry ◽  
X Ray ◽  
X Ray Scattering ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Triblock Terpolymers ◽  
Ray Scattering

The morphology and crystallization behavior of two triblock terpolymers of polymethylene, equivalent to polyethylene (PE), poly (ethylene oxide) (PEO), and poly (ε-caprolactone) (PCL) are studied: PE227.1-b-PEO4615.1-b-PCL3210.4 (T1) and PE379.5-b-PEO348.8-b-PCL297.6 (T2) (superscripts give number average molecular weights in kg/mol and subscripts composition in wt %). The three blocks are potentially crystallizable, and the triple crystalline nature of the samples is investigated. Polyhomologation (C1 polymerization), ring-opening polymerization, and catalyst-switch strategies were combined to synthesize the triblock terpolymers. In addition, the corresponding PE-b-PEO diblock copolymers and PE homopolymers were also analyzed. The crystallization sequence of the blocks was determined via three independent but complementary techniques: differential scanning calorimetry (DSC), in situ SAXS/WAXS (small angle X-ray scattering/wide angle X-ray scattering), and polarized light optical microscopy (PLOM). The two terpolymers (T1 and T2) are weakly phase segregated in the melt according to SAXS. DSC and WAXS results demonstrate that in both triblock terpolymers the crystallization process starts with the PE block, continues with the PCL block, and ends with the PEO block. Hence triple crystalline materials are obtained. The crystallization of the PCL and the PEO block is coincident (i.e., it overlaps); however, WAXS and PLOM experiments can identify both transitions. In addition, PLOM shows a spherulitic morphology for the PE homopolymer and the T1 precursor diblock copolymer, while the other systems appear as non-spherulitic or microspherulitic at the last stage of the crystallization process. The complicated crystallization of tricrystalline triblock terpolymers can only be fully grasped when DSC, WAXS, and PLOM experiments are combined. This knowledge is fundamental to tailor the properties of these complex but fascinating materials.

scholarly journals Effect of Molecular Architecture on Associating Behavior of Star-Like Amphiphilic Polymers Consisting of Plural Poly(ethylene oxide) and One Alkyl Chain

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 460
Author(s):  
Daisuke Kugimoto ◽  
Aoi Taniguchi ◽  
Masaki Kinoshita ◽  
Isamu Akiba
Keyword(s):  
Ethylene Oxide ◽  
Average Molecular Weight ◽  
Amphiphilic Polymers ◽  
Hydrophobic Core ◽  
Molecular Architecture ◽  
Polymer Micelles ◽  
The Core ◽  
X Ray Scattering ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Associating behavior of star-like amphiphilic polymers consisting of two or three poly(ethylene oxide) (PEO) chains and one stearyl chain (C18) was investigated. Although the aggregation number (Nagg) of linear analogue of amphiphilic polymers monotonically decreased with increasing number-average molecular weight of PEO (Mn,PEO), the Nagg of micelles of star-like amphiphilic polymers with Mn,PEO = 550 g/mol was smaller than that with Mn,PEO = 750 g/mol, whereas that with Mn,PEO ≥ 750 g/mol showed general Mn,PEO dependence. Small-angle X-ray scattering analyses revealed that the occupied area of one PEO chain on the interface between hydrophobic core and corona layer in the micelles of star-like polymers was much narrower than that in the linear amphiphilic polymers. This result indica ted the PEO chains of star-like polymers partially took unfavorable conformation near the core–corona interface in polymer micelles. The effect of local conformation of PEO chains near the interface on the associating behavior became significant as Mn,PEO decreased. Therefore, in polymer micelles of star-like amphiphilic polymers containing PEO with Mn,PEO = 550 g/mol, the enlargement of occupied area of PEO on the core–corona interface should be caused to avoid the formation of unfavorable conformations of partial PEO chains, resulting in a decrease in Naggs.

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