Chemical modification of natural rubber (NR) has frequently been attempted to improve the performance in specific application. 30% poly(methyl metacrylate) (PMMA) grafted into NR (MG30) has been explored as a potential candidate for polymer electrolytes. The complexation effect of salt and plasticizer in polymer host electrolytes had been investigated using FTIR. The carbonyl stretch of MG30 locates at 1729 cm-1, with the addition of lithium trimethanesulfonate (LiCF3SO3) salt, new band evolves at lower frequency region at 1643-1645 cm-1. The nondegenerate vibrational mode of nus(SO3) of salted electrolytes appearing at 1031-1034 cm-1 comes from 'free' trimethanesulfonate anions and the 1040-1046 cm-1 absorption from the monodentate ion paired with triflates. These indicate MG30-salt interaction. When MG30 and ethylene carbonate (EC) formed film, the CH3 asymmetric bend of MG30 appearing at 1447cm-1 is shifted to 1449 cm-1 in the EC-polymer complex. The CO stretching at 1729 cm-1 also shifted to 1728 cm-1. Hence, the EC-MG30 system is complexed to each other. EC-LiCF3SO3 interactions are indicated by the shifting of CO bending band of EC from 718 cm-1 being shifted to 720 cm-1 in the complex. In Li+-EC interaction where the ring breathing region at 897 cm-1 in EC has shifted to 899 cm-1 in EC-salt spectrum. The band appearing at 1643-1645 cm-1 due to the coordination of Li+
The (1)H-NMR shifts of the imidazolium protons of some novel dimeric ionic liquids were examined in various deuterated solvents. Interactions between the solvent and the imidazolium salt of butyl substituted ionic liquids were observed to give higher chemical shifts than methyl substitution.
In the solid form of the title imidazolium-based ionic liquid salt, C(18)H(24)N(4) (2+)·2CF(3)SO(3) (-), the complete cation is generated by a crystallographic inversion centre. The five-membered imidazole ring is approximately perpendicular to the six-membered phenyl-ene ring [dihedral angle = 85.11 (11)°]. In the crystal, the components are linked by C-H⋯O interactions.
The cation of the imidazolium-based ionic-liquid title salt, C(16)H(24)N(4) (2+)·2C(2)F(6)NO(4)S(2) (-), lies on a center of inversion; in the cation, the five-membered imidazolium ring is aligned at 84.4 (1)° with respect to the phenyl-ene ring; the angle at the methyl-ene C atom is 113.0 (2)°. In the anion, the negative charge formally resides on the two-coordinate N atom; the S-N-S angle at this atom is 125.2 (1)°.
The title salt, C(18)H(18)N(2) (2+)·2PF(6) (-), exists as non-inter-acting cations and anions. In the cation, the pyridine and phenyl-ene rings are aligned at 62.9 (1)°; the pyridine ring lies on a special position of m site symmetry and the phenyl-ene ring on a special position of 2/m site symmetry. The angle at the methyl-ene C atom is 112.8 (1)°. The anion lies on a special position of m site symmetry; four F atoms lie on this mirror plane.
The title imidazolium-based ionic-liquid salt, C(18)H(24)N(4) (2+)·2PF(6) (-), has the cation lying about a center of inversion. The five-membered imidazole ring is disordered over two positions (the methyl substituents are ordered). This imidazole ring is approximately perpendicular to the six-membered phenyl-ene ring [dihedral angle = 81.3 (8)° for one disorder component and 83.8 (8)° for the other; the two components are off-set by 2.7 (8)°]. The crystal is a non-merohedral twin with a twin component of 23%.
The title imidazolium-based ionic-liquid salt, C(18)H(24)N(4) (2+)·2BF(4) (-), has the cation lying about a center of inversion. The five-membered imidazole ring is approximately perpendicular to the six-membered phenyl-ene ring [dihedral angle = 86.9 (1)°]. The tetra-fluoro-borate anion is disordered over two sites in a 0.722 (3):0.278 (3) ratio.
The title imidazolium-based ionic-liquid salt, C(18)H(24)N(4) (2+)·2Br(-), has the cation lying about a center of inversion. The five-membered imidazole ring is disordered over two positions with the major component having a site occupancy of 0.712 (4); the N-bound methyl substituents are ordered. The imidazole ring is approximately perpendicular to the six-membered phenyl-ene ring [dihedral angle = 80.7 (5)° for the major disorder component and 89.8 (3)° for the other; the two components are off-set by 10.1 (6)°].
Crystallization of the ionic liquid 3,3'-dimethyl-1,1'-(1,4-phenylenedimethylene)diimidazolium bis(tetrafluoroborate), C(16)H(20)N(4)(2+).2BF(4)(-), (I), from its solution in water has permitted the first single-crystal study of an imidazolium-based ionic liquid having a tetrafluoroborate ion as counter-ion. Despite the expectation that the anion would not participate in nonclassical hydrogen bonding, the ionic liquid features C-H...F hydrogen bonds. The dication lies about a center of inversion. The ionic liquid 3,3'-di-n-butyl-1,1'-(1,4-phenylenedimethylene)diimidazolium bis(trifluoromethanesulfonate), C(22)H(32)N(4)(2+).2CF(3)SO(3)(-), (II), features both C-H...F and C-H...O hydrogen bonds.
A series of doped and un-doped magnetic adsorbents CuCexFe2-xO4 (x=0.0-0.5) for fluoride were prepared with the micro-emulsion method. Fluoride adsorption was optimized for solution pH, temperature, contact time, and initial concentration and was monitored via normal phase ion chromatography (IC). The effect of concomitant anions was also explored to perform and simulate competitive fluoride adsorption in real water samples. Optimal adsorption was discovered by a simple quadratic model based on central composite design (CCD) and the response surface method (RSM). The adsorption, electrochemical and magnetic properties were compared between doped and un-doped ferrites. Doped ferrites (x=0.1-0.5) were found to be superior to un-doped ferrites (x=0) regarding the active sites, functional groups and fluoride adsorption. The characterization, optimization and application results of the doped ferrites indicated enhanced fluoride adsorption and easy separation with a simple magnet.
The supramolecular structure of the inclusion complex of β-cyclodextrin (β-CD) with 1,1',2,2'-tetramethyl-3,3'-(p-phenylenedimethylene) diimidazolium dibromide (TetraPhimBr), a dicationic ionic liquid, has been investigated. The inclusion complex with 1:1 molar ratio was prepared by a kneading method. Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) analysis, (1)H NMR and thermogravimetric analysis (TGA) confirmed the formation of the inclusion complex. The results showed that the host-guest system is a fine crystalline powder. The decomposition temperature of the inclusion complex is lower than that of its parent molecules, TetraPhimBr and β-CD individually.
In the title compound, C(13)H(16)N(2)O(2), the planes of the benzimidazole ring system and the acetate O-C=O fragment make a dihedral angle of 84.5 (3)°. In the crystal, mol-ecules are connected through C-H⋯N hydrogen bonds to form infinite chains in the [-110] direction.
Imidazolium functionalized carboxylic acid forms a multi-component material with p-sulfonatocalix[4]arene and aquated lanthanide ions, stabilising dinuclear metal complexes for Y(3+) and Gd(3+). These have the simplest binding of two bridging carboxylates between the two metal centres (Y(3+)), or the same arrangement along with the simplest binding of one carboxylate bridging two metal ions for the larger metal ion (Gd(3+)).
The asymmetric unit of the title compound, C(20)H(28)N(2)O(6)S(2), contains one half-mol-ecule, related to the other half by a twofold rotation axis. The two aromatic rings of the mol-ecule make a dihedral angle of 50.91 (7)°. The O-CH(2)-CH(2)-O and N-CH(2)-CH(2)-O fragments both adopt gauche conformations, with torsion angles of 76.0 (4) and 70.4 (3)°, respectively. In the crystal, adjacent mol-ecules are linked through N-H⋯O hydrogen bonds into chains along the a-axis direction. The chains are further connected via C-H⋯O inter-actions into a two-dimensional supra-molecular network in the ac plane.
In the title compound, C(9)H(14)N(2)O(2), the imidazole ring and the acetate O-C=O plane make a dihedral angle of 80.54 (12)°. In the crystal, mol-ecules are connected via pairs of C-H⋯O hydrogen bonds, forming centrosymmetric dimers.
In the title compound, C(13)H(23)N(2)O(2) (+)·Br(-), the octyl chain has an all-trans conformation. In the crystal, the cations are linked by C-H⋯O bonds into a zigzag chain along the b axis. The bromide anions further link the chains via C-H⋯Br inter-actions into a two-dimensional array parallel to the ab plane. An O-H⋯Br interaction is also observed.
The title butterfly-shaped mol-ecule, C(11)H(6)N(2)O(2), is folded slightly along the O=C⋯C=O line, the dihedral angle between the two parts being 6.42 (3)°. In the crystal, adjacent mol-ecules are linked through C-H⋯O hydrogen bonds into infinite layers parallel to the ac plane. The layers are further connected into a three-dimensional netweork via π-π inter-actions formed between pairs of anti-parallel arranged mol-ecules, with a centroid-centroid distance between the central six-membered ring and the benzene ring of 3.4349 (9) Å.
The centroid of the central aromatic ring of the title mol-ecule, C(24)H(22)O(4), is located on an inversion center. The dihedral angle between the central and terminal benzene rings is 75.00 (7)°. In the crystal, mol-ecules are linked through C-H⋯O hydrogen bonds into chains along [121]. The chains are connected into layers via C-H⋯π inter-actions.
In the title compound, C(24)H(22)O(4), the centroid of the central benzene ring lies on a special position of 2/m site symmetry, while the terminal aromatic rings are located on a mirror plane. The central and terminal benzene rings are perpendic-ular to each other. In the crystal, the mol-ecules are connected via C-H⋯O hydrogen bonds into a three-dimensional polymeric structure. The network is further consolidated by a C-H⋯π inter-action.
In the title compound, C(29)H(24)N(4)O(4)S(3), the two N-tosyl-benzimidazolyl unit are connected through a -S-CH(2)- fragment, the dihedral angle between the benzimidazole rings being 76.09 (5)°. The methyl-thio group is disordered with respect to exchange of the S and C atoms in a 0.547 (4):0.453 (4) ratio. In the crystal, C-H⋯O and C-H⋯π inter-actions connect adjacent mol-ecules into infinite layers parallel to the ab plane. The crystal packing is further stabilized by a π-π inter-action [centroid-centroid separation = 3.5187 (4) Å].