Phenyl Side Groups Research Articles

Interaction of CYP3A4 with the inhibitor cobicistat: Structural and mechanistic insights and comparison with ritonavir

Cobicistat is a derivative of ritonavir marketed as a pharmacoenhancer for anti-HIV therapy. This study investigated the interaction of cobicistat with the target protein, drug-metabolizing cytochrome P450 3A4 (CYP3A4), at the molecular level using spectral, kinetic, functional, and structural approaches. It was found that, similar to ritonavir, cobicistat directly coordinates to the heme via the thiazole nitrogen but its affinity and the binding rate are 2-fold lower: 0.030 μM and 0.72 s−1, respectively. The newly determined 2.5 Å crystal structure of cobicistat-bound CYP3A4 suggests that these changes arise from the inability of cobicistat to H-bond to the active site S119 and establish multiple stabilizing contacts with the F–F’ connecting fragment, which becomes disordered upon steric clashing with the bulky morpholine moiety. Nonetheless, cobicistat inhibits recombinant CYP3A4 as potently as ritonavir (IC50 of 0.24 μM vs 0.22 μM, respectively) due to strong ligation to the heme and formation of extensive hydrophobic/aromatic interactions via the phenyl side-groups. To get insights into the inhibitory mechanism, the K257 residue, known to be solely and irreversibly modified by the reactive ritonavir metabolite, was substituted with alanine. Neither this nor control K266A mutation changed the extent of time-dependent inhibition of CYP3A4 by cobicistat and ritonavir, suggesting the existence of alternative inactivation mechanism(s). More importantly, K257 was found to be functionally important and contributed to CYP3A4 allosterism, possibly by modulating protein-ligand interactions through conformational dynamics.

Synthesis of O-B ← N embedded molecules and studies on the B ← N cleavage-driven thermo- and solvatochromic properties

Three O-B ← N embedded molecules identified as 1, 2, and 3 with different substituents and B ← N locations are synthesized to study the firmness of intramolecular B ← N coordination. After X-ray diffraction crystallography, electrochemical, and photophysical tests, in-depth B ← N cleavage-driven thermo- and solvatochromic studies were conducted. In contrast to compound 1 with phenyl side groups, compound 2 with bulky and electron-deficient perfluorophenyl substituents has twisted backbone, significantly increased fluorescence quantum yield (ΦF = 27 % vs 85 %), and most importantly, enhanced stability of B ← N coordination. Comparison to 1 and 2, whose B ← N bonds are located on the edge of fused rings, compound 3 with extended backbone conjugation and B ← N bonds embedded inside fused rings exhibits red-shifted absorption/emission, decreased ΦF = 7 %, and remarkably enhanced strength of B ← N coordination. This work discloses the effects of substituents and B ← N locations on firmness of intramolecular B ← N coordination, which are enlightening to understand the stability and application of these O-B ← N embedded molecules.

Gamma Radiolysis of Phenyl-Substituted TODGAs: Part II

ABSTRACT The radiolytic degradation chemistry of three phenylated analogs of N,N,N’,N’-tetraoctyl diglycolamide (TODGA) was investigated: 2-(2-(di-n-octylamino)-2-oxoethoxy)-N,N-di-n-octyl-2-phenylacetamide (PhTODGA), which has a phenyl substituent bound to a central methylene, 2-(2-(di-n-octylamino)-2-oxo-1-phenylethoxy)-N,N-di-n-octylpropanamide (PhMeTODGA), which also contains a methyl substituent bound to the methylene on the other side of the ether moiety, and, 2-(2-N-n-hexyl-N-phenylamino)-2-oxoethoxy)-N-n-hexyl-N-phenylacetamide (DHDPDGA), which has phenyl substituents located on the amide groups instead of the central methylenes. In Part II of this series of papers radiolytic degradation products were identified after separation with liquid chromatography by High Resolution, Accurate-Mass mass spectrometry and collision-induced dissociation. At least twenty-two radiolytic degradation products were identified for PhTODGA, twenty-nine for PhMeTODGA, and over three dozen for DHDPDGA. The suite of radiolytic degradation products of these three investigated ligands was significantly larger than has been reported for previously studied diglycolamides, owing to their asymmetric nature, and to the identification of several new degradation mechanisms, including addition of methyl, hydroxyl, and nitrogen oxide radicals, that have not been previously reported for diglycolamides. Degradation products that contained addition of a NO2 or NO3 group were particularly prevalent for DHDPDGA, likely due to the phenyl side-groups. Several of these newly observed mechanisms do not appear to depend on the presence of the phenyl groups, suggesting these novel mechanisms may apply to other diglycolamides

Atomic Oxygen-Induced Surface Erosion Behavior and Mechanical Degradation of Polyether Ether Ketone via Reactive Molecular Dynamics Simulations.

Atomic oxygen (AO) collision is one of the most serious threats to polymeric materials exposed to the space environment, yet understanding the structural changes and degradation of materials caused by AO impact remains a tremendous issue. Herein, we systematically evaluate the erosion collision and mechanical degradation of polyether ether ketone (PEEK) resin under hypervelocity AO impact using reactive molecular dynamics simulations. The interaction process and local evolution mechanism between high-speed AO and PEEK are investigated for the first time, suggesting that AO will either be scattered or adsorbed by PEEK, which is strongly correlated with the main degraded species evolution including O2, OH, CO, and CO2. Different AO fluxes and AO incidence angle simulations indicate that high-energy AO collision on the surface transfers kinetic energy to PEEK's thermal energy, thus inducing mass loss and surface penetration mechanisms. Vertically impacted AO causes less erosion on the PEEK matrix, rather than obliquely. Furthermore, PEEK chains modified with functional side groups are comprehensively investigated by 200 AO impact and high strain rate (1010 s-1) tensile simulations, demonstrating that the spatial configuration and stable benzene functionality of phenyl side groups can significantly improve the AO resistance and mechanical properties of PEEK at 300 and 800 K. This work revealed useful insights into the interaction mechanisms between AO and PEEK at the atomic scale and may provide a protocol for screening and designing new polymers of high AO tolerance.

Composition effects on thermodynamic properties and interfacial structure in styrene-butadiene rubber: A combined experimental and simulation study

Understanding the structure–property relationship of styrene-butadiene rubbers (SBRs) plays a directive role in the design and optimization of relevant elastomer composite products. Herein, we investigate the properties of four types of SBRs with different compositions and the corresponding interfacial properties of SBR/silica by using atomistic molecular dynamics (MD) simulation in combination with experimental measurements. We show that a lower content of styrene causes better thermal stability of SBR, and the inclusion of styrene/vinyl restricts the movement of the polymer chain and leads to an increase in the glass transition temperature (Tg). The composition effect is attributed to the presence of side groups in styrene and vinyl monomers, which noticeably affects the interfacial properties as well. The phenyl and vinyl side groups suppress the density fluctuations near the silica substrate, while promote the overall mass density in the first adsorption layer, and disturbs the ordered distribution of the main chain at the interface. The present work provides a basic understanding of the correlation between the composition and properties of the SBRs and SBR/silica and thus supplies theoretical guidance to the design of SBR and SBR nanocomposites for tire tread applications.

Study on Reliability and Selection of Silicone Grease Used for Coating at the Interface Between Cable and Accessory

Silicone grease coated at the interface of cables and accessories performs a good role in lubricating and sealing during installation, but the swelling impact of silicone grease on rubber insulation of accessories greatly affects the long-term reliability of the interface between cable and accessory. Until recently, no standard has been proposed to guide accessory manufacturers in choosing the best silicone grease. In this study, nine different silicone greases that were widely used for accessories installation were chosen. First, three types of silicone greases with outstanding anti-swelling properties were tested using a silicone rubber (SiR) swelling experiment. The properties of the three silicone greases chosen were then investigated further, including electrical and mechanical properties, moisture resistance, and corona resistance. The results reveal that dimethyl silicone with high viscosity or by inserting phenyl side groups can minimize SiR swelling and then enhance its mechanical qualities. However, perfluoropolyether grease outperforms dimethyl silicone in terms of swelling resistance, chemical inertness, and excellent thermal stability. Thus, SiR coated with perfluoropolyether grease can maintain excellent mechanical properties after different aging. However, because of its high polarity, it can cause significant charge buildup at the interface between cables and accessories, particularly under direct current (dc) electrical stress. Consequently, perfluoropolyether grease will have a negative effect on the use in dc environment. Moreover, silicone greases after inorganic doping absorb moisture easily, resulting in a high relative dielectric constant that will have a negative effect on the use in a humid environment.

Study of vibrational spectra of polycyclic aromatic hydrocarbons with phenyl side group

Computational study of polycyclic aromatic hydrocarbons (PAHs) with phenyl side group substituted at different positions is reported. The infrared spectral variations due to the position of phenyl substitution, ionization state and the size of the molecules are discussed and possible contribution of phenyl-PAHs to the mid-infrared emission features from astrophysical objects is analysed. Structurally phenyl group substitution at 2nd position gives more stable species compared to substitution at other positions. Phenyl-PAHs exhibit new aromatic bands near 695 and 741 cm−1 (14.4 and 13.5μm), due to contribution from quintet CH wag, that compare well with minor features at 14.2 and 13.5μm observed in several astrophysical objects. Just as in plain PAHs, the C–C stretch vibrational modes (∼1600 cm−1) have negligible intensity in neutrals, but the cations of all phenyl-PAHs exhibit significantly strong phenyl group C–C stretch peak close to class B type 6.2μm astrophysical band. In 2-phenylpyrene, it is the neutral molecule that exhibits this strong feature in the 6.2μm range along with other features that match with sub-features at 6.66 and 6.9μm, observed in astronomical spectra of some late type objects. The substitution of phenyl side group at solo position shifts the C–C stretch mode of parent PAH close to the region of 6.2μm astrophysical band. The results indicate possibility of phenyl-PAHs in space and the bottom-up formation of medium sized compact PAHs with phenyl side group in carbon rich cool circumstellar shells. Phenyl-PAHs need to be considered in modelling mid-infrared emission spectra of various astrophysical objects.

Adhesion of Bis-Salphen-Based Coordination Polymers to Graphene: Insights from Free Energy Perturbation Study.

Manipulation of nanoscale objects using molecular self-assembly is a potent tool to achieve large scale nanopatterning with small effort. Coordination polymers of bis-salphen compounds based on zinc have demonstrated their ability to align carbon nanotubes into micro-scale networks with an unusual "rings-and-rods" pattern. This paper investigates how the compounds interact with pristine and functionalized graphene using density functional theory calculations and molecular dynamic simulations. Using the free energy perturbation method we will show how the addition of phenyl side groups to the core compound and functionalization of graphene affect the stability, mobility and conformation adopted by a dimer of bis-(Zn)salphen compound adsorbed on graphene surface and what it can reveal about the arrangement of chains of bis-(Zn)salphen polymer around carbon nanotubes during the self-assembly of microscale networks.

Synthesis of a Novel Rigid Semi-Alicyclic Dianhydride and Its Copolymerized Transparent Polyimide Films' Properties.

A new series of colorless polyimides (CPIs) with outstanding thermal properties and mechanical properties were fabricated by the copolymerization of a novel dianhydride and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with 2,2′-bistrifluoromethyl benzidine (TFDB). The novel dianhydride, 10-oxo-9-phenyl-9-(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetraacid dianhydride (3FPODA), possessed a rigid semi-alicyclic structure, –CF3 and phenyl side groups, and an active carbonyl group. Benefitting from the special structure of 3FPODA, the glass transition temperatures (Tg) of the new CPIs improved from 330 °C to 377 °C, the coefficient of thermal expansion (CTE) decreased from 46 ppm/K to 24 ppm/K, and the tensile strength (TS), tensile modulus (TM), and elongation at break (EB) increased from 84 MPa to 136 MPa, 3.2 GPa to 4.4 GPa, and 2.94% to 4.13% with the increasing amount of 3FPODA, respectively. Moreover, the active carbonyl group of the 3FPODA could enhance the CPI’s adhesive properties. These results render the new dianhydride 3FPODA an ideal candidate monomer for the fabrication of high-performance CPIs.

Soluble Liquid Crystalline Poly(ester imide)s with High Glass Transition Temperatures and Improved Dielectric Properties

At present, high-performance liquid crystalline polyesters with a good processability, low dielectric constant, and low dielectric loss at a high frequency (GHz) are in high demand ascribed to the rapid development of high-speed communication technology. Here, an imide dicarboxylic acid (IA) with a bulky phenyl side group is designed and synthesized. It is then copolymerized with 4-hydroxybenzoic acid (HBA), isophthalic acid (IPA), 4,4′-dihydroxybipheny (BP), and 4,4′-dihydroxydiphenyl ether (ODP) via solution polycondensation to obtain liquid crystalline poly(ester imide)s (LCPEIs). By controlling the feeding ratio of IA, the solubility, thermal stability, mechanical properties, and dielectric properties of the LCPEIs are tunable. When the molar fraction of IA reaches or exceeds 5%, the obtained LCPEIs are soluble in ordinary organic solvents, such as chloroform, N,N-dimethylformamide, N-methyl-2-pyrrolidinone, and so forth, which allows a simple solution casting to prepare isotropic LC films. The nematic LCPEIs show high glass transition temperatures (Tg > 200 °C) but relatively low melting temperatures and isotropization temperatures (Tm and Ti, <340 °C). The LCPEI prepared with 10 mol % IA shows excellent combined properties, whose ηinh, Mn (GPC), Tg, Tm, Ti, Td5%, tensile strength, tensile modulus, water uptake, dielectric constant, and dielectric loss (at 10 GHz) are 0.92 dL g–1, 20,900 g mol–1, 218 °C, 268 °C, 330 °C, 458 °C, 80.5 MPa, 4.0 GPa, 0.39%, 3.07, and 0.006, respectively. These LCPEIs can be promising candidates for flexible copper-clad laminate substrates.

Effect of phenyl side groups on the dielectric properties and dielectric behavior of polysiloxane

Over the past decades, polysiloxane-based dielectric elastomers (DEs) have attracted significant research attention; however, the low dielectric constant and poor breakdown strength of polysiloxane limit its application in DEs. In this study, the effect of phenyl side groups on the dielectric properties and unique dielectric relaxation behavior of polymethyl phenyl siloxane (PMPS) was investigated. The dielectric constant of PMPS was slightly improved from 3.45 to 3.60 by introducing appropriate amount of the phenyl side groups into polysiloxane. Moreover, the electrical breakdown strength of PMPS increased from 31.70 to 35.91 kV mm−1. The contribution of the α- and β-relaxations significantly increased the dielectric loss of PMPS. To better understand the effect of the phenyl side groups on these properties, the dielectric relaxation behavior of copolymers with different phenyl contents was studied in detail via broadband dielectric spectroscopy and thermally stimulated depolarization current measurements. This study paves a new path to design and prepare polysiloxane-based soft materials with high dielectric constant and improved electrical breakdown strength.

Assessing pyrolysis behavior of silicon-containing arylacetylene resin via experiments and ReaxFF MD simulations

Silicon-containing arylacetylene resin (PSA), a thermosetting organic-inorganic hybrid resin of high heat-resistance performs well in ablation process, whereas its pyrolysis behavior under high temperature has not been fully interpreted. Herein, the PSA pyrolysis process was in-depth investigated by experiments and ReaxFF molecular dynamics simulation (ReaxFF-MD). TG results show that the temperature of 5% weight loss (Td5) is above 600 ℃, and the residue at 900 ℃ surpass 85%, demonstrating PSA has excellent heat resistance and thermal stability. The on-line FTIR and out-line gas quantify analysis reveals that H2 and CH4 are dominant gaseous products, which are also unveiled by ReaxFF-MD simulation. Molecular reaction tracking indicates PSA pyrolysis is initiated by the cleavage of skeleton in benzene ring, the cleavage of C-C bond and C-Si bond in main chain at elevated temperature. Hydrogen abstraction reactions are primary formation pathways of CH4 and H2, together with conquering high energy barriers. The activation energy of PSA pyrolysis in experiments is 155 kJ/mol, agreeing well with that from ReaxFF MD simulations (144 kJ/mol), which further confirms the thermochemical stability of cured PSA that rich in highly crosslinked aromatic structure. Besides, the influence of silicon side-groups on PSA pyrolysis is screened by MD and results indicate that gases evolution depended largely on side-groups types and decreasing side phenyl groups in PSA is benefit for improving its thermal stability. This work deepens the understanding of PSA pyrolysis mechanism and provides theoretical guidance for improving its heat resistance.

Effect of side groups on the properties of silicon‐containing arylacetylene resins

AbstractFour silicon‐containing arylacetylene resins were synthesized by polycondensation of Grignard reagent of m‐diethynylbenzene with methylethyldichlorosilane, dimethyldichlorosilane, methylphenyldichlorosilane, and diphenyldichlorosilane, respectively. The structures of the resins were verified by nuclear magnetic resonance spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The solubility, crystallinity, and rheological character of the resins were characterized. The curing behavior was traced by differential scanning calorimetry (DSC) and FTIR analyses. The effect of the side groups on the silicon atom on the properties was investigated. The results show that the resins with asymmetrical side groups display better processability (wide processing window) as compared with those with symmetrical side groups. The resin with side phenyl groups shows higher flexural strength but lower thermal stability as compared with those without side phenyl groups. Meanwhile, the side phenyl groups also enhance the temperature at which secondary relaxation occurs.

Alkyl‐Chain Branching of Non‐Fullerene Acceptors Flanking Conjugated Side Groups toward Highly Efficient Organic Solar Cells

AbstractSide‐chain modifications of non‐fullerene acceptors (NFAs) are essential for harvesting their full potential in organic solar cells (OSC). Here, an effective alkyl‐chain‐branching approach of the Y‐series NFAs flanking meta‐substituted phenyl side groups at the outer positions is demonstrated. Compared to BTP‐4F‐PC6 with linear m‐hexylphenyl chains, two new acceptors named BTP‐4F‐P2EH and BTP‐4F‐P3EH are developed with bulkier alkyl chains branched at the β and γ positions, respectively. These branched chains result in altered molecular packing of the NFAs and afford higher open‐circuit voltage of the devices. Despite the blue‐shifted absorption of the branched‐chain NFAs, their blends with PBDB‐T‐2F enable improved short‐circuit current density for the corresponding devices owing to the more suitable phase separation and better exciton dissociation. Consequently, the OSCs based on BTP‐4F‐P2EH and BTP‐4F‐P3EH yield enhanced device performance of 18.22% and 17.57%, respectively, outperforming the BTP‐4F‐PC6‐based ones (17.22%). These results highlight that the side‐chain branching design of NFAs has great potential in optimizing molecular properties and promoting photovoltaic performance.

Modulating the Excited-State Decay Pathways of Cu(I) 4H-Imidazolate Complexes by Excitation Wavelength and Ligand Backbone.

Cu(I) 4H-imidazolato complexes are excellent photosensitizers with broad and intense light absorption properties, based on an earth-abundant metal, and hold great promise as photosensitizers in artificial photosynthesis and for accumulation of redox equivalents. In this study, the excited-state relaxation dynamics of three novel heteroleptic Cu(I) 4H-imidazolato complexes with phenyl, tolyl, and mesityl side groups are systematically investigated by femtosecond and nanosecond time-resolved transient absorption spectroscopy and theoretical methods, complemented by steady-state absorption spectroscopy and (spectro)electrochemistry. After photoexcitation into the metal-to-ligand charge transfer (MLCT) and intraligand charge transfer absorption band, fast (0.6-1 ps) intersystem crossing occurs into the triplet MLCT manifold. The triplet-state population relaxes via the geometrical planarization of the N-aryl rings on the Cu(I) 4H-imidazolato complexes. Depending on the initial Franck-Condon state, the remaining small singlet state population relaxes into two geometrically distinct minima geometries with similar energy, S1/2,relax and S3/4,relax. Subsequent ground-state recovery from S1/2,relax and internal conversion from S3/4,relax to S1/2,relax take place on a 100 ps time scale. The internal conversion can be understood as hole transfer from a dyz-orbital to a dxz-orbital, which is accompanied with the structural reorganization of the coordination environment. Generally, the photophysical processes are determined by the steric hindrance of the side groups on the ligands. And the excited singlet-state pathways are dependent on the excitation wavelength.

Aryl‐group substituted polysiloxanes with high‐optical transmission, thermal stability, and refractive index

AbstractPolysiloxanes are an important class of polymers for optoelectronic applications. Novel polysiloxanes with high‐refractive index (RI) based on phenanthrenyl‐substituted monomers are prepared by a polycondensation reaction starting from various substituted dialkoxysilanes as monomers. The substitution patterns on the Si atom are systematically changed to vary the properties of the linear polymers as well as the final cured material. The two monomers with polycyclic aromatic side groups 9‐phenanthrenylmethyldimethoxysilane and 9‐phenanthrenylphenyldimethoxysilane are synthesized and fully characterized, including their single crystal X‐ray structures. Linear polysiloxanes with variations in hydride, methyl, vinyl, phenyl, and phenanthrenyl side group content are prepared by acid‐ and base‐catalyzed polycondensation reactions. Both SiH and Si vinyl substituted polymers with molecular weights up to 30 kDa and adjustable RI's from 1.52 to 1.63 are obtained and the thermally cured by Pt‐catalyzed hydrosilylation reactions. Polysiloxane resins are obtained with high‐RI's, optical transmittance above 95% and thermal stabilities up to 420°C. Long‐term thermal stability tests show transmittance values above 85% even after 60 days of thermal treatment at 180°C.

Optimal method for preparing sulfonated polyaryletherketones with high ion exchange capacity by acid‐catalyzed crosslinking for proton exchange membrane fuel cells

AbstractSulfonated polyaryletherketones (SPAEK) bearing four sulfonic acid groups on the phenyl side groups were synthesized. The benzophenone moiety of polymer backbone was further reduced to benzydrol group with sodium borohydride. The membranes were crosslinked by acid‐catalyzed Friedel‐Crafts reaction without sacrifice of sulfonic acid groups and ion exchange capacity (IEC) values. Crosslinked membranes with the same IEC value but different water uptake could be prepared. The optimal crosslinking condition was investigated to achieve lower water uptake, better chemical stability (Fenton's test), and higher proton conductivity. In addition, the hydrophilic ionic channels from originally course and disordered could be modified to be narrow and continuous by this crosslinking method. The crosslinked membranes, CS4PH‐40‐PEKOH (IEC = 2.4 meq./g), reduced water uptake from 200 to 88% and the weight loss was reduced from 11 to 5% during the Fenton test compared to uncrosslinked one (S4PH‐40‐PEK). The membrane showed comparable proton conductivity (0.01–0.19 S/cm) to Nafion 212 at 80°C from low to high relative humidity (RH). Single H2/O2 fuel cell based on the crosslinked SPAEK with catalyst loading of 0.25 mg/cm2 (Pd/C) exhibited a peak power density of 220.3 mW/cm2, which was close to that of Nafion 212 (214.0 mW/cm2) at 80°C under 53% RH. These membranes provide a good option as proton exchange membrane with high ion exchange capacity for fuel cells.

Poly(aryl ether ketone ketone)s containing diphenyl-biphthalazin-dione moieties with excellent thermo-mechanical performance and solubility

High molecular weight poly(aryl ether ketone ketone)s comprising diphenyl-biphthalazin-dione moieties (P-MDs) were prepared through the solution condensation. The structure of polymers was characterized via nuclear magnetic resonance spectra and infrared absorption spectrum. The effects of mixed diphenyl-biphthalazin-dione (mDBD) monomer on performance of polymers were investigated. The mDBD units containing side phenyl groups endow polymer with solubility and controllable contact angle. The resultant polymers perform a fine thermo-stability in both nitrogen and air, presenting an excellent thermal resistance with glass transition temperature in the range of 253–333 °C. Simultaneously, the polymers exhibit a favorable solubility in 1,1,2,2-tetrachloroethane and N-methylpyrrolidone, showing fine film-formation performance. Polymers possess excellent mechanic performance with the tensile strength up to 84 MPa, the Young’s modulus above 1.5 GPa and the retention of storage modulus at 250 °C as high as 70%. Additionally, the contact angle of water-drops with polymer films is within the range of 73.5°–89.1°.

Relation between Morphology and Chiroptical Properties in Chiral Conducting Polymer Films: A Case Study in Chiral PEDOT.

The electronic properties of conducting polymers are influenced by their micro- and macrostructural orders, which can be tailored by substituent modification. However, while the effect of substituents on conducting polymers is extensively investigated, chiral substituents are far less studied. Furthermore, many chiral conducting polymers have regioirregular structures, which result in polymer films with inferior properties. In this work, we apply electronic circular dichroism (ECD) spectroscopy to study the morphological changes to the chiral polymers under different polymerization conditions. For this purpose, we investigated 3,4-ethylenedioxythiophene (EDOT) derivatives having two stereogenic centers on each monomer and bearing methyl or phenyl side groups (dimethyl-EDOT and diphenyl-EDOT, respectively). Polymerizing the enantiomerically pure monomers produces regioregular and stereoregular dimethyl-PEDOT and diphenyl-PEDOT, respectively. The effect of the electrolyte and solvent on polymer film morphology was studied using scanning electron microscopy (SEM) and ECD, showing a correlation between the polymer’s morphology and the chiroptical properties of its films. We found that, for diphenyl-PEDOT, the combination of perchlorate anion electrolyte and acetonitrile solvent resulted in a unique morphology characterized by significant intermolecular interactions. These interactions were clearly observable in the ECD spectra in the form of exciton couplings, whose presence was supported by TD-DFT calculations. A small enantiomeric excess was sufficient to induce very intense ECD signals, demonstrating chiral amplification in electropolymerized films.

Self-cleaning and Oil/Water Separation of 3D Network Super-hydrophobic Bead-like Fluorinated Silica Pellets/Poly(aryl ether ketone) Composite Membrane Fabricated via a Facile One-step Electrospinning

Novel super-hydrophobic fluorinated silica pellets/poly(aryl ether ketone) composite membranes with controllable structure have been prepared through incorporating poly(aryl ether ketone)s with (3-trifluoromethyl)-phenyl side groups and fluorinated silica pellets(F-SiO2) by a facile one-step electrospinning. Under the condition of adding 50%(mass fraction) F-SiO2 in the composite membrane, the water contact angle(WCA) reached its maximum (157°±4.3°). The controllable micro/nano-structures grown on the electrospun fibers could be regulated by the F-SiO2 loading, which was illustrated by scanning electron microscopy(SEM). Moreover, these super-hydrophobic membranes also demonstrated excellent durability, anti-fouling property and oil-water separation ability after 200 h of water flushing. These promising PAEK composite membranes with controllable structure have the potential values in large-scale application of filtration, oil-water separation and antifouling.