- RAFT polymerization and thio-bromo substitution: An efficient way towards well-defined glycopolymers
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Despite an increasing effort to design well-defined glycopolymers, the convenient synthesis of polymers with higher DPs (>100) and without tedious protection and deprotection steps remains a challenge. Combining the reversible addition fragmentation transfer (RAFT) polymerization and the efficient substitution of primary bromo groups by thiols, we were able to synthesize a set of well-defined glycopolymers with DPs of up to 115. With the polymerization of the highly reactive monomer (2-bromoethyl)-acrylate polymers with low dispersities were obtained that could efficiently be functionalized with various sugar thiol(ate)s. In particular, derivatives of d-glucose, d-galactose, and d-mannose gave excellent degrees of functionalization close to quantitative conversion using only a slight excess of the thiol. This atom efficient synthesis can even be applied for copolymers with acid or base labile components due to the use of unprotected sugar moieties and, hence, the lack of further deprotection steps. Binding studies with the lectin concanavalin A and the subsequent competition studies with α-d-methyl-mannopyranose (αMeMan) proved the effective binding of these derivatives and revealed a DP- and carbohydrate-dependent clustering and dissolution.
- Pr?hl, Michael,Englert, Christoph,Gottschaldt, Michael,Brendel, Johannes C.,Schubert, Ulrich S.
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- Network structure and strong microphase separation for high ion conductivity in polymerized ionic liquid block copolymers
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A series of strongly microphase-separated polymerized ionic liquid (PIL) diblock copolymers, poly(styrene-b-1-((2-acryloyloxy)ethyl)-3-butylimidazolium bis(trifluoromethanesulfonyl)imide) (poly(S-b-AEBIm-TFSI)), were synthesized to explore relationships between morphology and ionic conductivity. Using small-angle X-ray scattering and transmission electron microscopy, a variety of self-assembled nanostructures including hexagonally packed cylinders, lamellae, and coexisting lamellae and network morphologies were observed by varying PIL composition (6.6-23.6 PIL mol %). At comparable PIL composition, this acrylate-based PIL block copolymer with strong microphase separation exhibited ～1.5-2 orders of magnitude higher ionic conductivity than a methacrylate-based PIL block copolymer with weak microphase separation. Remarkably, we achieved high ionic conductivity (0.88 mS cm-1 at 150 °C) and a morphology factor (normalized ionic conductivity, f) of ～1 through the morphological transition from lamellar to a coexistence of lamellar and three-dimensional network morphologies with increasing PIL composition in anhydrous single-ion conducting PIL block copolymers, which highlights a good agreement with the model predictions. In addition to strong microphase separation and the connectivity of conducting microdomains, the orientation of conducting microdomains and the compatibility between polymer backbone and IL moiety of PIL also significantly affect the ionic conductivity. This study provides avenues to controlling the extent of microphase separation, morphology, and ion transport properties in PIL block copolymers for energy conversion and storage applications.
- Choi, Jae-Hong,Ye, Yuesheng,Elabd, Yossef A.,Winey, Karen I.
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- Poly(bromoethyl acrylate): A Reactive Precursor for the Synthesis of Functional RAFT Materials
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Postpolymerization modification has become a powerful tool to create a diversity of functional materials. However, simple nucleophilic substitution reactions on halogenated monomers remains relatively unexplored. Here we report the synthesis of poly(bromoethyl acrylate) (pBEA) by reversible addition-fragmentation chain transfer (RAFT) polymerization to generate a highly reactive polymer precursor for postpolymerization nucleophilic substitution. RAFT polymerization of BEA generated well-defined homopolymers and block copolymers over a range of molecular weights. The alkylbromine-containing homopolymer and block copolymer precursors were readily substituted by a range of nucleophiles in good to excellent conversion under mild and efficient reaction conditions without the need of additional catalysts. The broad range of nucleophilic species that are compatible with this postmodification strategy enables facile synthesis of complex functionalities, from permanently charged polyanions to hydrophobic polythioethers to glycopolymers.
- Barlow, Tammie R.,Brendel, Johannes C.,Perrier, Sébastien
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- Mitochondria-Targeted delivery and light controlled release of iron prodrug and CO to enhance cancer therapy by ferroptosis
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Mitochondrial malfunction is considered to be a decisive signal of apoptosis. It would be a promising strategy to target mitochondria in cancer cells to generate reactive oxygen species (ROS), thus directly inducing mitochondrial damage. We herein reported a mitochondria-Targeted, photo-responsive polymer (Mito-PNBE), which can self-Assemble into nanoparticles (Fe-CO@Mito-PNBE) encapsulated with diphenylcyclopropenone (light-responsive CO prodrugs) and aminoferrocene-based prodrugs via hydrophobic interactions. Upon UV-irradiation, the rapid release of CO and aminoferrocene-based prodrugs caused by disassembly was observed. On one hand, the released carbon monoxide in mitochondria could enhance ROS generation and accelerate oxidative metabolism. On the other hand, the aminoferrocene-based prodrugs will release Fe3+/Fe2+ ions in the tumor microenvironment, thus triggering the Fenton reaction, which generates more ROS and damages the mitochondria. Thus, the synergistic effect of the two drugs produces enough amounts of ROS in the mitochondria, leading to mitochondrial collapse with an enhanced cancer therapeutic effect. This multifunctional platform has potential in precision cancer therapy.
- Gao, Fan,Gao, Fan,Zhang, Wen-Jian,Hong, Chun-Yan,You, Ye-Zi,Nie, Xuan,Zhang, Ze,Chen, Guang,Xia, Lei,Wang, Long-Hai,Zhang, Wen-Jian,Hong, Chun-Yan,You, Ye-Zi,Wang, Fei,Wang, Chang-Hui,Hao, Zong-Yao
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supporting information
p. 3478 - 3486
(2020/03/06)
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- Solid-state, individual dispersion of single-walled carbon nanotubes in ionic liquid-derived polymers and its impact on thermoelectric properties
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The structure of carbon nanotubes and their electronic interaction with a matrix are important for extracting the unprecedented electronic properties, which have yet to be explored. Here we investigate the dispersibility of single-walled carbon nanotubes (SWNTs) in ionic liquid-derived polymers (PILs), revealed by cross-sectional transmission electron microscopy, infrared optical spectroscopy, and Raman spectroscopy. Surprisingly, SWNTs studied here are highly dispersed, at least down to 7.5 nm-fibres, in a trimethylammonium-suspended PILs. Based on this discovery, we found that the well-dispersed and almost fully dispersed SWNTs in PILs are responsible for the enhanced thermoelectric properties, a future energy harvesting technique.
- Nakano, Motohiro,Nonoguchi, Yoshiyuki,Nakashima, Takuya,Hata, Kenji,Kawai, Tsuyoshi
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p. 2489 - 2495
(2016/01/20)
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- The formation of a slipped cofacial dimer of zinc (II) tripyridylporphyrin in water-soluble polymer
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A novel tripyridylporphyrin monomer, 5-[4-[2-(acryloyloxy)ethoxy]phenyl]- 10,15,20-tris(4-pyridyl)porphyrin (TrPyP), and its zinc (II) complex (ZnTrPyP) were synthesized. It was copolymerized with acrylamide to prepare water-soluble polymer P(ZnTrPyP-AM).
- Ding, Kewei,Wang, Fei,Wu, Feipeng
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experimental part
p. 64 - 69
(2012/02/01)
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- COMPOUND, COMPOSITION, RETARDATION PLATE, ELLIPTICALLY-POLARIZING PLATE AND LIQUID-CRYSTAL DISPLAY DEVICE
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A compound useful for fabrication of retardation plates, which is represented by the formula (DI): wherein Y11 to Y13 represent methine or nitrogen; R11 to R13 represent a group of the formula (DI-A) below or ot
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Page/Page column 58-59
(2008/06/13)
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- COMPOUND, COMPOSITION AND THIN FILM
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A liquid-crystalline compound of the following formula:wherein Y11, Y12 and Y13 are methine or N; L1, L2 and L3 are single bond or divalent group; H1, H2 and H3/
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Page/Page column 42/1-43
(2010/10/20)
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- New selective syntheses of (Meth)acrylic monomers: Isocyanates, isocyanurates, carbamates and ureas derivatives
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The selective formulation of ω-isocyanatoalkyl (meth)acrylates may be conveniently obtained by simple condensation of potassium cyanate with ω-halogeno-alkyl (meth)acrylates under appropriated phase transfer catalytic conditions. Depending on the reaction media and the temperature, these isocyanate derivatives may be isolated, trimerized to the corresponding isocyanurates or trapped in situ as carbamates or ureas compounds.
- Dubosclard-Gottardi, Christine,Caubere, Paul,Fort, Yves
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p. 2561 - 2572
(2007/10/02)
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- A new synthesis of thiocyanatoalkyl (meth)acrylic esters
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The selective sunthesis of thiocyanatoalkyl meth(acrylic) esters were obtained with 71 to 95% yield under phase transfer catalysis from corresponding chloro- and bromoalkyl (meth)acrylic esters and potassium thiocyanate in presence of potassium iodide.
- Berthe,Fort,Caubere
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p. 617 - 628
(2007/10/02)
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- The 'Baylis - Hillman reaction' mechanism and applications revisited
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It is shown that reaction of aryl, benzyl, alkyl and functionalised alkyl acrylic esters with benzaldehyde, in the presence of 1,4-diazabicyclo[2.2.2] octane, strongly depends upon the electronic and steric effects of the ester part. This influence is also observed in condensation of furfuraldehyde. Moreover, for the first time, it is shown that the overall condensation is equilibrated.
- Fort, Yves,Berthe, Marie Christine,Caubere, Paul
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p. 6371 - 6384
(2007/10/02)
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