Anionic Mechanism Research Articles

Control of Platinum Loss in WEEE Smelting

In spite of significant economic value, the solubilities of the platinum group and precious metals in metallurgical copper smelting slags are not well known. Recent experimental information on iron-free and low-iron silicate melts indicates that the chemical solubility of platinum is very low, < 1 ppmw (part per million weight). In this study, the concentration of platinum in alumina spinel-saturated iron silicate slags in equilibrium with a solid iron-platinum alloy was measured as a function of oxygen partial pressure at 1300°C. The results were converted to unit activity of platinum by the thermodynamic properties of the iron-platinum alloy formed. This allowed the mechanism of dissolution of platinum in the slag and the forms of platinum species in alumina-rich iron silicate slags in copper scrap smelting and refining conditions to be obtained. Our findings explain some inconsistent results in the geochemical literature by proposing an anionic dissolution mechanism at low oxygen partial pressures in iron-containing silicate slags.

Chloride transporters and channels in β-cell physiology: revisiting a 40-year-old model.

It is accepted that insulin-secreting β-cells release insulin in response to glucose even in the absence of functional ATP-sensitive K+ (KATP)-channels, which play a central role in a ‘consensus model’ of secretion broadly accepted and widely reproduced in textbooks. A major shortcoming of this consensus model is that it ignores any and all anionic mechanisms, known for more than 40 years, to modulate β-cell electrical activity and therefore insulin secretion. It is now clear that, in addition to metabolically regulated KATP-channels, β-cells are equipped with volume-regulated anion (Cl–) channels (VRAC) responsive to glucose concentrations in the range known to promote electrical activity and insulin secretion. In this context, the electrogenic efflux of Cl– through VRAC and other Cl– channels known to be expressed in β-cells results in depolarization because of an outwardly directed Cl– gradient established, maintained and regulated by the balance between Cl– transporters and channels. This review will provide a succinct historical perspective on the development of a complex hypothesis: Cl– transporters and channels modulate insulin secretion in response to nutrients.

Discovery of a New Family of Polyoxometalate-Based Hybrids with Improved Catalytic Performances for Selective Sulfoxidation: The Synergy between Classic Heptamolybdate Anions and Complex Cations.

A series of functional cation-regulated isopolymolybdate-based organic-inorganic hybrid compounds, Na2H2[Mo4O12(C8H17O5N)2]·10H2O (1), Na2[M(Bis-tris)(H2O)]2[Mo7O24]·10H2O [M = Cu, 2; Ni, 3; Co, 4; Zn, 5; Bis-tris = 2,2-Bis(hydroxymethyl)-2,2',2″-nitrilotriethanol], and (NH4)2[M(Bis-tris)(H2O)]2[Mo7O24]·6H2O (M = Zn, 6; Cu, 7), were synthesized and characterized toward advanced molecular catalyst design. Compound 1 is a covalently bonded adduct, and its self-assembly process can be probed by electrospray ionization mass spectrometry (ESI-MS). Compounds 2-7 are polyoxometalate (POM)-based hybrids containing classic heptamolybdate anions and complex cations with Bis-tris ligands. All of these compounds showed remarkable catalytic effects for selective sulfide oxidation. To the best of our knowledge, compound 5 presents the best catalytic activity so far among the reported hybrid materials with common easily synthesized small-molecule POM clusters and also exhibits outstanding reliability. The conclusion of the catalytic effect is drawn from the results that Zn-based compounds have better catalytic effects than other transition-metal-containing compounds and the compound constructed by Na+ has higher catalytic activity than that constructed by NH4+. The mechanism studies show that the improvements of the catalytic performance are caused by the synergy between classic heptamolybdate anions and complex cations. ESI-MS data and UV-vis spectra revealed that the POM anions can form intermediate peroxomolybdenum units during catalytic reaction. Further, the combination of the substrate thioanisole with complex cations was characterized by NMR experiments and UV-vis spectra. Thus, a new synergistic mechanism of anions and cations is proposed in which the activated thioanisole is used as a nucleophile to attack the peroxomolybdenum bonds, and this provides a new strategy in the design of reliable POM-based catalysts.

Immobilization efficiency and mechanism of metal cations (Cd2+, Pb2+ and Zn2+) and anions (AsO43- and Cr2O72-) in wastes-based geopolymer

In this study, a composite geopolymer based on solid wastes (drinking water treatment residue (DWTR) and granulated blast furnace slag (GBFS)) were used in immobilization of heavy metals cations (Cd2+, Pb2+ and Zn2+) and anions (AsO43− and Cr2O72-). For evaluating the immobilization effect for heavy metals, the mechanical strength and leaching properties of geopolymers were investigated. Meanwhile, different characterization methods were used to research the immobilization mechanisms. The results indicated that the mechanical strength of geopolymers containing heavy metals was effectively improved by 37.11% with addition of DWTR. The stability of metals in geopolymer were increased and the release risk was decreased under the effect of DWTR. Characterization results verified the uniform distribution of heavy metals in geopolymer, and the adding of Pb2+, AsO43− and Cr2O72- caused the formation of crystalline phases. After the adding of heavy metals, the chemical environment change of Al 2p is more significant than Si 2p. Based on 29Si and 27Al MAS-NMR results, the different metals show various influences on the silicon and aluminum species in geopolymer matrix, and the strength of polymerized structure is mainly based on the Q4(mAl).

Preparation and Characterization of High-Viscosity Montmorillonite

AbstractHydrophobicity, high viscosity, and dispersion are important properties for organo-montmorillonites, and all organo-montmorillonite configurations have yet to be fully characterized with respect to this property. High-viscosity montmorillonite (Mnt) is useful in gels and as an adsorber. The current study focused on modifying Mnt using organic cations and anions of various chain lengths in batch experiments with various concentrations and ratios. The viscosity of organic Mnt reached up to 395 mP.s. Molecular dynamics simulations and X-ray diffraction (XRD) were used to identify the conditions and arrangement of organic cations and anions in the Mnt interlayer area. The intercalation mechanism of organic cations and anions was also determined, providing a theoretical basis for the preparation of high-viscosity Mnt.

Platinum nano-flowers with controlled facet planted in titanium dioxide nanotube arrays bed and their high electro-catalytic activity

To better platinum's (Pt’s) electro-catalytic activity for oxidizing methanol, nano-flowers structured Pt catalysts with controlled facet had been planted onto titanium dioxide nanotube array (TNA) bed via a pulse electrodepositing method in an acid electrolyte containing chloroplatinic acid (H2PtCl6). The facet of Pt nano-flowers can be tuned as (111) or (100) by adding sulfuric acid (H2SO4) or hydrochloric acid (HCl) respectively into the precursor. It has been discovered that the nano-flower structured Pt catalysts with (111) facet generates a current density peak of 243.16 mA·mg−1(~2 times that of Pt catalysts with (200) facets) for catalytic oxidizing methanol in electrolyte containing 1 M methanol and 0.5 M H2SO4. In addition, the concentration of sulfuric acid in electrolyte has an effect on electrode's morphology, its electro-catalytic capability and stability. The mechanism of sulfuric acid anion for bettering Pt’s electro-catalytic activity had been comparatively investigated by replacing H2SO4 as HCl in precursor.

Ionic-Equilibrium-Based Mechanism of •OH Conversion to Dichloride Radical Anion in Aqueous Acidic Solutions by Kinetic and Theoretical Studies.

A new mechanism for the dichloride radical anion (Cl2•-) formation in diluted acidic chloride solutions is proposed on the grounds of pulse radiolysis measurements of the optical absorption growth at 340 nm and the density functional theory and Hartree-Fock computations. We show that the rate of •OH conversion into Cl2•- is determined by the equilibrium concentration of the ionic pair H3O+·Cl-. According to the proposed mechanism, the diffusional encounter of •OH and H3O+·Cl- is followed by fast concerted charge/proton transfer ( k(25 °C) = 6.2 × 1012 s-1) to yield Cl•, which then reacts with Cl- to produce Cl2•-. The mechanism has been confirmed by the observed first-order growth of the Cl2•- absorption and a direct proportionality of the rate constant to the activities of H3O+ and Cl- ions. The salt effect on the rate of Cl2•- formation is due to the ionic strength effect on the equilibrium H3O+ + Cl- ⇄ H3O+·Cl-.

The effects of H+, NH3OH+ and NH4+ on the thermal decomposition of bistetrazole N-oxide anion.

The bistetrazole N-oxide energetic ionic salt dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) has attracted great interest as it breaks through the limitations of the traditional nitro group, high detonation velocity and moderate impact sensitivity. Reports show that TKX-50 transforms into the 5,5'-bis(2-hydroxytetrazole) (BTO) precursor, which is further decomposed and partly converted to diamino 5,5'-bistetrazole-1,1'-diolate (ABTOX). Studying the effects of H+, NH3OH+ and NH4+ on the thermal decomposition mechanism of bistetrazole N-oxide anion would provide a more comprehensive understanding of the TKX-50 decomposition mechanism. Herein, TKX-50, BTO and ABTOX decomposition rates, on-line analysis of the gas products, as well as quantitative analysis, are presented. It was found that the presence of two H+ decreases the decomposition temperature, whereas NH3OH+ greatly increases the decomposition rate. In the presence of NH3OH+, the bistetrazole N-oxide anion completely decomposes without producing C2N2; however, NH4+ promotes the polymerization of C2N2 generated by the bistetrazole N-oxide anion, and the amount of NO produced is greater than that of N2O. Therefore, in the TKX-50 decomposition process, the bistetrazole N-oxide anion does not receive two H+ simultaneously and converts into BTO. Furthermore, the competition between cations and their decomposition products for the H+ affects the degree of decomposition, which is important in understanding the energy release mechanism.

Multiscale Modeling of Structure, Transport and Reactivity in Alkaline Fuel Cell Membranes: Combined Coarse-Grained, Atomistic and Reactive Molecular Dynamics Simulations.

In this study, molecular dynamics (MD) simulations of hydrated anion-exchange membranes (AEMs), comprised of poly(p-phenylene oxide) (PPO) polymers functionalized with quaternary ammonium cationic groups, were conducted using multiscale coupling between three different models: a high-resolution coarse-grained (CG) model; Atomistic Polarizable Potential for Liquids, Electrolytes and Polymers (APPLE&P); and ReaxFF. The advantages and disadvantages of each model are summarized and compared. The proposed multiscale coupling utilizes the strength of each model and allows sampling of a broad spectrum of properties, which is not possible to sample using any of the single modeling techniques. Within the proposed combined approach, the equilibrium morphology of hydrated AEM was prepared using the CG model. Then, the morphology was mapped to the APPLE&P model from equilibrated CG configuration of the AEM. Simulations using atomistic non-reactive force field allowed sampling of local hydration structure of ionic groups, vehicular transport mechanism of anion and water, and structure equilibration of water channels in the membrane. Subsequently, atomistic AEM configuration was mapped to ReaxFF reactive model to investigate the Grotthuss mechanism in the hydroxide transport, as well as the AEM chemical stability and degradation mechanisms. The proposed multiscale and multiphysics modeling approach provides valuable input for the materials-by-design of novel polymeric structures for AEMs.

Effect of the Chloride Anions on the Formation of Self-Assembled Diphenylalanine Peptide Nanotubes.

Self-assembled peptide nanostructures are being intensively investigated due to their potential applications such as biosensors, piezotransducers, and microactuators. It was predicted that their formation and hence piezoelectric property strongly depend on the water content and acidity of the stock solution. In this paper, simple diphenylalanine (FF) tubular structures were fabricated from the solutions with added hydrochloric acid in order to understand the influence of chloride ions on the self-assembly process and resulting piezoelectricity. Low-frequency Raman scattering, atomic, and piezoresponse force microscopies were used to characterize both the morphology and piezoelectric properties of the grown samples. The mechanism of chloride anions' effect on the formation of self-assembled peptide nanostructures is discussed based on the acquired Raman data and quantum-chemical modeling. It is shown that the addition of chloride anions causes a significant reduction of the dipole moments of FF tubes accompanied with the concomitant decrease of tube dimensions and apparent shear piezoelectric coefficients.

Hydrogeochemistry and quality of groundwater in a part of Damodar Valley, Eastern India: an integrated geochemical and statistical approach

The influence of geochemical processes and quality of groundwater in a rural tract of Damodar Valley region were investigated. The study has distinguished the groundwater as fresh, soft to moderately hard and mainly CaHCO3 type. The paired samples student’s t test shows the significant seasonal variations of pH, HCO3−, and Fe. Amphoteric exchange has lessened HCO3− concentration in post-monsoon which subsequently has caused to drop pH. Quite the reverse, the monsoon precipitation has triggered the additional release of Fe from iron-bearing sediments. The contaminant Cl− is from the domestic wastewater as is evidenced by field observations. The inter-variable relations, cation and anion mechanisms, and mineral saturation indices reveal that the dissolutions of silicate and carbonate minerals are the primary sources of major ions in groundwater. The chloro-alkaline indices showed the role of ion exchange too in water chemistry. The R-mode factor analysis also successfully identified two dominant processes regulating water chemistry—geogenic sources (Ca2+, Mg2+, Na+, and HCO3−) and anthropogenic inputs (mainly Cl−). The groundwater is found unsuitable for drinking at 82 and 93% of wells in pre- and post-monsoon seasons, respectively mainly due to elevated Fe content. The water from more than 90% of wells is appropriate for irrigation uses. The study recommends the proper treatment of contaminated water for consumption and measures to protect the groundwater from the waste water infiltration.

Roads to pentazolate anion: a theoretical insight.

The formation mechanism of pentazolate anion (PZA) is not yet clear. In order to present the possible formation pathways of PZA, the potential energy surfaces of phenylpentazole (PPZ), phenylpentazole radical (PPZ-R), phenylpentazole radical anion (PPZ-RA), PPZ and m-chloroperbenzoic acid (m-CPBA), p-pentazolylphenolate anion (p-PZPolA) and m-CPBA, and p-pentazolylphenol (p-PZPol) and m-CPBA were calculated by the computational electronic structure methods including the hybrid density functional, the double hybrid density functional and the coupled-cluster theories. At the thermodynamic point of view, the cleavages of C–N bonds of PPZ and PPZ-R need to absorb large amounts of heat. Thus, they are not feasible entrance for PZA formation at ambient condition. But excitation of PPZ and deprotonation of PPZ-RA probably happen before cleavage of C–N bond of PPZ at high-energy condition. As to the radical anion mechanism, the high accuracy calculations surveyed that the barrier of PZA formation is probably lower than that of dinitrogen evolution, but the small ionization potential of PPZ-RA gives rise to the unstable ionic pair of sodium PPZ at high temperature. In respect of oxidation mechanism, except for PPZ, the reactions of p-PZPolA and p-PZPol with m-CPBA can form PZA and quinone. The PZA formations have the barriers of about 20 kcal mol−1 which compete with the dinitrogen evolutions. The stabilities of PZA in both solid and gas phases were also studied herein. The proton prefers to transfer to pentazolyl group in the (N5)6(H3O)3(NH4)4Cl system which leads to the dissociation of pentazole ring. The ground states of M(N5)2(H2O)4 (M = Co, Fe and Mn) are high-spin states. The pentazolyl groups confined by the crystal waters in the coordinate compounds can improve the kinetic stability. As to the reactivity of PZA, it can be persistently oxidized by m-CPBA to oxo-PZA and 1,3-oxo-PZA with the barriers of about 20 kcal mol−1.

A theoretical investigation about sensing mechanism of fluoride anion for (E)‐2‐(2‐(dimethylamino)ethyl)‐6‐(4‐hydroxystyryl)‐1H‐benzo[de]‐isoquinoline‐1,3 (2H)‐dione

AbstractIn the present work, we theoretical study the sensing mechanism of a new fluoride chemosensor (E)‐2‐(2‐(dimethylamino)ethyl)‐6‐(4‐hydroxystyryl)‐1H‐benzo[de]‐isoquinoline‐1,3(2H)‐dione (the abbreviation is NIM). Based on density functional theory and time‐dependent density functional theory methods, the fluoride anion response mechanism has been confirmed via constructing potential energy curve. The exothermal deprotonation process along with the intermolecular hydrogen bond O–H···F reveals the uniqueness of detecting F−. After capturing hydrogen proton forming NIM‐A anion configuration, a new absorption peak around 655 nm appears in dimethyl sulfoxide solvent. In addition, the emission of NIM can be quenched when adding F− has been also confirmed. Due to the twisted intramolecular charge transfer character NIM‐A‐S1 form, we further verify the experimental phenomenon. The theoretical electronic spectra (vertical excitation energies and fluorescence peak) reproduced previous experimental results (ACS Appl. Mater. Interfaces 2014, 6, 7996), which not only reveals the rationality of our theoretical level used in this work but also confirms the correctness of geometrical attribution. In view of the excitation process, the strong intramolecular charge transfer process of S0 → S1 transition explain the redshift of absorption peak for NIM with the addition of fluoride anion. This work presents a straightforward sensing mechanism (deprotonation process) of fluoride anion for the novel NIM chemosensor.

The sensing mechanism of fluoride anion for a novel molecule D2: Desilylation and intramolecular charge transfer

In this work, the sensing mechanism of a new fluoride chemosensor 12‐([tert‐butyldiphenylsilyl]oxy)‐8a,13a‐dihydro‐7H‐benzo[de]benzo[4,5]imidazo[2,1‐a]‐isoquinolin‐7‐one (abbreviated as D2) is investigated using density functional theory (DFT) and time‐dependent DFT (TDDFT) methods. The theoretical electronic spectra (vertical excitation energies and fluorescence peak) reproduced previous experimental results (D. Li et al., Spectrochim. Acta A Mol. Biomol. Spectrosc. 2017, 185, 173), which confirms the rationality of the theoretical level used in this work. The constructed potential energy curve of the desilylation process suggests that the low barrier could be responsible for the rapid response to fluoride anions. Analyses of the binding energies show that only fluoride anion can be detected by D2 chemosensor in dimethylsulfoxide (DMSO). In view of the excitation process, the strong intramolecular charge transfer (ICT) process of the S0 → S1 transition explains the red shift of the absorption peak of the D2 sensor with the addition of fluoride anions. This work not only presents a straightforward sensing mechanism of sensing of the fluoride anion by the D2 chemosensor but should also play an important role in the synthesis and design of fluorescent sensors in future.

Influence of cathodic duty cycle on the properties of tungsten containing Al2O3/TiO2 PEO nano-composite coatings

Current waveforms with different cathodic duty cycles of 0, 20 and 40% were applied to coat 7075 aluminum alloy in a silicate based electrolyte containing titania nano-particles. Using a constant current mode, the recorded voltage-time response showed that the required voltage for PEO coating process is lower in the presence of sodium tungstate as additive. By increasing the cathodic duty cycle, pancake surface morphology was converted to crater-like. Phase and chemical composition of the coatings were investigated by using grazing angle XRD and SEM/EDS. The tungsten concentration decreased linearly with the increase of cathodic duty cycle, which is dissimilar to the titania content. It was proposed that physical entrapping has been associated with electrophoretic incorporation of titania nano-particles, while the adsorption mechanism of tungstate anions is purely electrophoretic. Corrosion performance of the coatings was evaluated by potentiodynamic polarization and EIS measurements. Addition of sodium tungstate was detrimental for corrosion performance of the coating in the case of unipolar waveform while the corrosion resistance was improved when bipolar waveforms were used. Long-term corrosion behavior of the coatings was investigated by EIS up to 16 weeks. The results showed remarkable difference between corrosion performance of the coatings produced by unipolar and bipolar waveforms, but the difference was negligible for the coatings produced by the bipolar waveforms with different cathodic duty ratios.

Fabrication, controlled release, and kinetic studies of indomethacin—layered zinc hydroxide nanohybrid and its effect on the viability of HFFF2

ABSTRACTThe intercalation of indomethacin into the interlayer gallery of layered zinc hydroxide (LZH) has been successfully executed using the simple ion exchange approaches. The synthesized intercalation compound, indomethacin-LZH nanohybrid, was characterized using PXRD, FTIR, SEM, BET, and STA. From the PXRD results, the intercalation of indomethacin anions into the interlayer gallery of LZH was successful; showing the formation of a new peak at lower 2θ with a basal spacing of 21.96 Å. FTIR analysis of the nanohybrid further supported the presence of indomethacin in the interlayer of the indomethacin-LZH nanohybrid. STA analysis confirms that the nanohybrid has higher thermal stability than pure indomethacin. The in vitro release mechanism of the indomethacin anions from the indomethacin-LZH nanohybrid showed slow release, with 95% and 78% release in phosphate buffer saline (PBS) solution at pH 4.8 and 7.4, respectively. The release behavior of indomethacin from its intercalation compounds in PBS solution at pH 4.8 and 7.4 follows the Higuchi model. In addition, the nanohybrid treated with normal fibroblast cell line shows that it reduces cell viability in a dose and time-dependent manner. This study shows that the high potential of the nanohybrid as an encapsulated material for the controlled release formulation of nonsteroidal anti-inflammatory (NASID) anions.

First Investigations Towards the Feasibility of an Al/Br2 Battery Based on Ionic Liquids

AbstractWe present first investigations towards the feasibility of an Al/Br2 battery based on ionic liquids (ILs). The charged battery consisted of an Al anode, a bromoaluminate IL as the anolyte, an ion‐exchange membrane, a polybromide IL as the catholyte, and an inert cathode. The open‐circuit voltage (OCV) of the battery was strongly dependent on the molar ratio of AlBr3 in the anolyte with values of 1.9 V when using a Lewis basic anolyte and 1.1 V when using a Lewis neutral anolyte. NMR studies with different organic cations in both electrolytes revealed the migration of organic cations as major charge‐balancing ions, which leads to a reduced theoretical energy density of 33 Wh L−1 (as opposed to 166 Wh L−1 for an anion mechanism). The battery could be discharged with high discharge resistance values of up to 3 kΩ cm2, and preliminary charging attempts revealed high overpotentials. Hitherto, an Al/Br2 cell with a Lewis basic anolyte could be used as primary battery with an OCV of 1.9 V.

Layered double hydroxide nanoparticles customization by polyelectrolyte adsorption: mechanism and effect on particle aggregation

Adsorption of polyelectrolytes (PEs) is a common strategy for stabilizing nanoparticles and customizing their properties. Although scarcely explored for layered double hydroxide nanoparticles (LDH-NPs), it can be used to increase their functionality in pharmaceutical and biomedical applications, among others. In this work, LDH-NPs intercalated with chloride, ibuprofen and ketoprofen were synthesized and modified with carboxylate containing PEs with different structures and physicochemical properties. The PEs adsorption mechanism on LDH-NPs and its effect on the aggregation of the obtained hybrids were studied by zeta potential and hydrodynamic diameter determinations on chloride intercalated LDH-NPs dispersions in the presence of polyacrylate (PA) at different concentrations. PA adsorption behavior was compared to that of citrate anion to contrast the adsorption mechanism of PEs and anions. Afterwards, the study was extended to other PEs (alginate and carbomer) as well as to drug intercalated LDH-NPs. PA adsorbed at the surface of LDH-NPs with high affinity: at low concentrations, PA was irreversibly adsorbed due to the positive structural charge of LDH-NPs and the flexible and negatively charged structure of PA. This high affinity caused a particle charge inversion, which results in negatively charged LDH-NPs stabilized by both electrostatic interactions and steric hindrance. Due to their structure, alginate and carbomer showed a lower affinity and, consequently, a lower capacity to produce LDH-NPs disaggregation. Finally, PEs adsorption allowed enhancing the disaggregation and modifying the interfacial properties of both ibuprofen and ketoprofen intercalated LDH-NPs producing only a small release of the drug loading.

Anion- and Solvent-Induced Rotary Dynamics and Sensing in a Perylene Diimide [3]Catenane.

A novel dynamic [3]catenane consisting of a large four-station central macrocycle which incorporates a bay tetrachloro-functionalized perylene diimide (PDI) unit and two triazolium anion-binding motifs, mechanically bonded with two smaller isophthalamide-containing macrocycles, is constructed using an anion template synthetic methodology. Proton NMR, electronic absorption, and fluorescence emission spectroscopies together with molecular dynamics simulations are used to investigate the anion recognition- and solvent-dependent dynamic properties of the higher-order mechanically interlocked molecule. Importantly, unprecedented solvent-dependent and anion-binding-induced circumrotatory motion in a hetero[3]catenane system is demonstrated where the exotic dual rotary switching behavior provides a unique and sophisticated mechanism for optical anion sensing in competitive protic organic and aqueous-organic media.

Ring-Opening Polymerization of Epoxides: Facile Pathway to Functional Polyethers via a Versatile Organoaluminum Initiator

We report a new class of organoaluminum-based initiator for anionic ring-opening polymerization of epoxides that is simple to synthesize from readily available precursors. The resultant organometallic initiator was the triethylaluminum adduct of (2-dibenzylamino)ethoxydiethylaluminum (TAxEDA) [(AlEt3)·(O(AlEt2)CH2CH2N(Bn)2)], which was isolated by direct crystallization from the reaction medium and then compositionally and structurally characterized by NMR spectroscopy and XRD. We studied the reactivity and versatility of the new initiator through the polymerization of propylene oxide, butylene oxide, epichlorohydrin, and allyl glycidyl ether into homopolymer, statistical copolymer, and block copolymer architectures with heterobifunctional end-groups consisting of dibenzylamine and hydroxyl functionalities. The TAxEDA-initiated polymerizations were consistent with a controlled, living, anionic mechanism that was tolerant of chemical functionality and exhibited no chain transfer to monomer that limits the ...