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Faiz Mohammad - One of the best experts on this subject based on the ideXlab platform.
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Dodecylbenzenesulfonic Acid micelles assisted in situ preparation and enhanced thermoelectric performance of semiconducting polyaniline zirconium oxide nanocomposites
Journal of Industrial and Engineering Chemistry, 2013Co-Authors: Tarique Anwer, Mohd Omaish Ansari, Faiz MohammadAbstract:Abstract Herein, we report in situ preparation of Dodecylbenzenesulfonic Acid (DBSA) micelles assisted polyaniline (Pani)/zirconium oxide (ZrO 2 ) nanocomposites (Pani/ZrO 2 ) by using K 2 S 2 O 8 as an oxidizing agent. Thus prepared nanocomposites were characterized by SEM, FTIR, XRD and UV–vis spectrophotometry. DBSA acted as dopant/surfactant, and the incorporation of ZrO 2 nanoparticles improved the stability, electrical and thermal properties of nanocomposites. From the results of UV–vis absorbance it was observed that Pani/ZrO 2 nanocomposite was more stabilized under UV light than Pani. DC electrical conductivity retention was studied by isothermal and cyclic ageing techniques and was observed to be better than Pani under ambient environmental conditions.
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Dodecylbenzenesulfonic Acid micelles assisted in situ preparation and enhanced thermoelectric performance of semiconducting polyaniline–zirconium oxide nanocomposites
Journal of Industrial and Engineering Chemistry, 2013Co-Authors: Tarique Anwer, Mohd Omaish Ansari, Faiz MohammadAbstract:Abstract Herein, we report in situ preparation of Dodecylbenzenesulfonic Acid (DBSA) micelles assisted polyaniline (Pani)/zirconium oxide (ZrO 2 ) nanocomposites (Pani/ZrO 2 ) by using K 2 S 2 O 8 as an oxidizing agent. Thus prepared nanocomposites were characterized by SEM, FTIR, XRD and UV–vis spectrophotometry. DBSA acted as dopant/surfactant, and the incorporation of ZrO 2 nanoparticles improved the stability, electrical and thermal properties of nanocomposites. From the results of UV–vis absorbance it was observed that Pani/ZrO 2 nanocomposite was more stabilized under UV light than Pani. DC electrical conductivity retention was studied by isothermal and cyclic ageing techniques and was observed to be better than Pani under ambient environmental conditions.
Jitai Li - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 2 3 disubstituted 2 3 dihydroquinazolin 4 1h ones catalyzed by Dodecylbenzenesulfonic Acid in aqueous media under ultrasound irradiation
Ultrasonics Sonochemistry, 2015Co-Authors: Baohua Chen, Jitai Li, Guofeng ChenAbstract:Synthesis of 2,3-disubstituted-2,3-dihydroquinazolin-4(1H)-one derivatives catalyzed by Dodecylbenzenesulfonic Acid was carried out in 80-92% yields at 40-42 °C within 1-2 h in aqueous media via one-pot three-component condensation of isatoic anhydride, aromatic aldehyde and amine under ultrasound irradiation. Convenient work-up procedures, mild reaction conditions, avoiding the use of organic solvents, and friendly to environment are the salient features of this protocol.
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synthesis of 2 1 5 diaryl 1 4 pentadien 3 ylidene hydrazinecarboximidamide hydrochloride catalyzed by p Dodecylbenzenesulfonic Acid in aqueous media under ultrasound irradiation
Ultrasonics Sonochemistry, 2012Co-Authors: Jitai Li, Chao Du, Xiaoya Xu, Guofen ChenAbstract:Abstract Amidinohydrazone compounds are very important synthetic intermediates and can serve as versatile precursors in synthesis of many natural products and drug molecules. The use of ultrasound, p-Dodecylbenzenesulfonic Acid (DBSA) and water as solvent improved the synthesis of different 2-(1,5-diaryl-1,4-pentadien-3-ylidene)-hydrazinecarboximidamide hydrochlorides. The best reaction conditions for the condensation of 1,5-diphenyl-1,4-pentadien-3-one with aminoguanidine hydrochloride were as follows: 1,5-diphenyl-1,4-pentadiene-3-one (1, 1 mmol), aminoguanidine hydrochloride (1.1 mmol), DBSA (0.5 mmol), water 10 mL, reaction temperature 25–27 °C, irradiation frequency 25 kHz. 2a was achieved in 94% yield within 2 h. The other seven amidinohydrazones were obtained in 84–94% yield within 2–3 h under the same conditions. Compared to the method involving catalysis by hydrochloric Acid in refluxing EtOH, the advantages of present procedure are milder conditions, shorter reaction times, higher yields, and environmental friendly conditions, which make it a useful strategy for the synthesis of analogues.
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efficient synthesis of 12 aryl 8 9 10 12 tetrahydrobenzo a xanthen 11 one derivatives catalyzed by p Dodecylbenzenesulfonic Acid in aqueous media under ultrasound irradiation
Synthetic Communications, 2012Co-Authors: Jitai Li, Yanwei Li, Yali SongAbstract:Abstract An efficient synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one derivatives via the three-component condensation of aromatic aldehyde, 2-naphthol, and 5,5-dimethyl-1,3-cyclohexanedione was carried out in 76–93% yields at 40–42 °C using p-Dodecylbenzenesulfonic Acid as catalyst in aqueous media under ultrasound irradiation.
Hsin-lung Chen - One of the best experts on this subject based on the ideXlab platform.
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molecular architecture effect on microphase separation in supramolecular comb coil complexes of polystyrene block poly 2 vinylpyridine with Dodecylbenzenesulfonic Acid anbn heteroarm star copolymer
Macromolecules, 2005Co-Authors: Bhanu Nandan, Hsin-lung Chen, Wenchang ChenAbstract:The microphase separation in a supramolecular comb−coil block copolymer formed by the stoichiometric complexation of an amphiphilic surfactant, Dodecylbenzenesulfonic Acid (DBSA), with the poly(2-vinylpyridine) (P2VP) blocks in a nonlinear heteroarm (PS)5(P2VP)5 star copolymer has been investigated. The hierarchical structure in the ordered state and the relevant order−disorder transitions (ODT) of the complex have been revealed using small-angle X-ray scattering (SAXS). The results were compared with those obtained previously for linear PS-b-P2VP(DBSA) and block-arm (PS-b-P2VP)5(PS)5(DBSA) complexes [Macromolecules 2005, 38, 10117] to illustrate the effect of block copolymer architecture on the self-assembly behavior of the supramolecular comb−coil complexes. The heteroarm (PS)5(P2VP)5(DBSA) complex exhibited structure-within-structure morphology in which the larger-scale PS cylindrical microdomains were embedded in the matrix consisting of the smaller-scale lamellar mesophase organized by the P2VP(DBSA)...
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self assembly in the bulk complexes of poly ethylene oxide with amphiphilic Dodecylbenzenesulfonic Acid
Langmuir, 2002Co-Authors: Hsin-lung Chen, Chungchi KoAbstract:We studied the self-assembly behavior in the bulk complexes of poly(ethylene oxide) (PEO) with an amphiphilic Dodecylbenzenesulfonic Acid (DBSA) formed through hydrogen bonding. In the hydrate state, PEO−DBSA complexes self-organized into a lamellar morphology consisting of alternating stacks of polar and nonpolar layers. The interlamellar distance increased with decreasing binding fraction of DBSA due to increasing inclusion of unbound monomer units into the polar layers. In the disordered state the comblike structure persisted and a “correlation hole” peak was present in the corresponding small-angle X-ray scattering (SAXS) profile. Complexation with PEO greatly promoted the thermal stability of the mesophase and the dynamics of mesophase formation as compared with those in pure DBSA. The faster mesophase formation in the complexes was proposed to stem from the higher isotropization temperature as well as the existence of comblike structure in the disordered melt.
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Supramolecular structure of the solid-state complexes of polyacrylamide and Dodecylbenzenesulfonic Acid
Journal of Polymer Research, 1999Co-Authors: Hsin-lung Chen, Min-ni ChangAbstract:The solid-state complexes of a flexible polymer, polyacrylamide (PAA), and an amphiphilic surfactant, Dodecylbenzenesulfonic Acid (DBSA), have been investigated. Complexation between PAA and DBSA occurred via proton transfer from DBSA to the carbonyl group in PAA, giving rise to a “supramolecular comb-like polymer” with ionic bonding. The mesomorphic phase in the complexes was identified by the birefringent patterns under polarized optical microscopy. Wide angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) revealed that the complexes microphase separated into a lamellar morphology consisting of alternating polar and nonpolar layers with the long period of ca. 3 nm. As the composition x (the average number of DBSA molecules bound with a PAA repeating unit) ≥ 0.7, the SAXS profiles were characterized by a major scattering peak associated with the flat lamellar structure. Multiple scattering peaks were observed at lower degree of complexation (x ≤ 0.6), which were ascribed to the formation of undulated lamellae that organized into a macrolattice with the diffraction patterns observable by SAXS. Preliminary assignments of the lattice planes suggested that the lobes of the undulated lamellae organized into body centered cubic (bcc) or simple cubic (sc) types of unit cell. The glass transition temperature of the polar layers in PAA(DBSA) complexes increased with increasing degree of complexation owing to the stiffening of polymer chains. Complexation with DBSA also enhanced the thermal stability of PAA, where the thermal decomposition temperature can be raised by as much as 35 °C.
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Self-Assembled Mesomorphic Complexes of Branched Poly(ethylenimine) and Dodecylbenzenesulfonic Acid
Macromolecules, 1999Co-Authors: Hsin-lung Chen, Ming-siao HsiaoAbstract:Solid-state complexes of flexible polymers with surfactants (surf) exhibit mesomorphic phase and microphase-separated lamellar morphology. Because the surf molecules are strongly associated with the polymer backbone, the ordered packing of the alkyl tails should be cooperative with the chain packing in the polymer layers which is influenced by chain topology. In this study, the supramolecular structure and thermal properties of the complexes of a highly branched poly(ethylenimine) (PEI) with Dodecylbenzenesulfonic Acid (DBSA) were investigated. Polarized optical microscopy and small-angle X-ray scattering (SAXS) revealed the presences of mesomorphic phases and microphase-separated lamellar morphology in the complexes. The ordered supramolecular structure was observed not only for the stoichiometric composition but over a wide composition range. The thicknesses of polymer and surf layers were determined from the one-dimensional correlation function. The surf layer thickness varied with complex composition....
Olli Ikkala - One of the best experts on this subject based on the ideXlab platform.
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mesomorphic state of poly vinylpyridine Dodecylbenzenesulfonic Acid complexes in bulk and in xylene solution
Macromolecules, 1995Co-Authors: Olli Ikkala, Janne Ruokolainen, Ten G Brinke, Mika Torkkeli, R SerimaaAbstract:Theoretically, lyotropic behavior of flexible polymers can be induced by associating the polymers with a large amount of long-tail surfactants leading to bottle-brush type conformations in suitable solvents. To address this and related questions, complexes of poly(2-vinylpyridine) (P2VP) and poly(4-vinylpyridine) (P4VP) with p-Dodecylbenzenesulfonic Acid (DBSA), characterized by FT-IR, were investigated in the bulk and in xylene, i.e., a good solvent for the alkyl side chains. At a 1:1 molar ratio of vinylpyridine monomer and DBS, the polymers are shown by FT-IR to be almost completely protonated. In the bulk, the complexes form mesomorphic layer structures which have been characterized by polarized optical microscopy and by both wide- and small-angle X-ray scattering. In the xylene solutions, birefringence indicating liquid crystallinity is observed for concentrations of the fully protonated P4VP-(DBSA)(1.0) complex of ca. 50% (w/w) and higher. In contrast, for P2VP(DBSA)(1.0), this is only observed at complex concentrations of ca. 70% (w/w) and higher. The mesomorphic behavior of P4VP(DBSA)(1.0) in xylene was further demonstrated by SAXS.
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heat induced transition to the conducting state in polyaniline Dodecylbenzenesulfonic Acid complex
Synthetic Metals, 1995Co-Authors: Markus Ahlskog, H Isotalo, Olli Ikkala, Jukka Laakso, H Stubb, J E OsterholmAbstract:Abstract Polyaniline (PANI) doped with Dodecylbenzenesulfonic Acid (DBSA) is a new conducting polymer complex which combines high electrical conductivity with processability. The doping reaction of PANI/DBSA has been found to be a time-dependent process which can be accelerated by heating. This process has been studied by measuring the conductivity during heat treatment in complexes with a molar DBSA ratio, relative to PANI, varying from 0.55 to 1.12. The temperature for the onset of conductivity depends on the mixture ratio. Conductivities on the order of 1 S/cm were achieved.
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Heat-induced transition to the conducting state in polyaniline/Dodecylbenzenesulfonic Acid complex
Synthetic Metals, 1995Co-Authors: Markus Ahlskog, H Isotalo, Olli Ikkala, Jukka Laakso, H Stubb, J E OsterholmAbstract:Abstract Polyaniline (PANI) doped with Dodecylbenzenesulfonic Acid (DBSA) is a new conducting polymer complex which combines high electrical conductivity with processability. The doping reaction of PANI/DBSA has been found to be a time-dependent process which can be accelerated by heating. This process has been studied by measuring the conductivity during heat treatment in complexes with a molar DBSA ratio, relative to PANI, varying from 0.55 to 1.12. The temperature for the onset of conductivity depends on the mixture ratio. Conductivities on the order of 1 S/cm were achieved.
R Serimaa - One of the best experts on this subject based on the ideXlab platform.
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mesomorphic state of poly vinylpyridine Dodecylbenzenesulfonic Acid complexes in bulk and in xylene solution
Macromolecules, 1995Co-Authors: Olli Ikkala, Janne Ruokolainen, Ten G Brinke, Mika Torkkeli, R SerimaaAbstract:Theoretically, lyotropic behavior of flexible polymers can be induced by associating the polymers with a large amount of long-tail surfactants leading to bottle-brush type conformations in suitable solvents. To address this and related questions, complexes of poly(2-vinylpyridine) (P2VP) and poly(4-vinylpyridine) (P4VP) with p-Dodecylbenzenesulfonic Acid (DBSA), characterized by FT-IR, were investigated in the bulk and in xylene, i.e., a good solvent for the alkyl side chains. At a 1:1 molar ratio of vinylpyridine monomer and DBS, the polymers are shown by FT-IR to be almost completely protonated. In the bulk, the complexes form mesomorphic layer structures which have been characterized by polarized optical microscopy and by both wide- and small-angle X-ray scattering. In the xylene solutions, birefringence indicating liquid crystallinity is observed for concentrations of the fully protonated P4VP-(DBSA)(1.0) complex of ca. 50% (w/w) and higher. In contrast, for P2VP(DBSA)(1.0), this is only observed at complex concentrations of ca. 70% (w/w) and higher. The mesomorphic behavior of P4VP(DBSA)(1.0) in xylene was further demonstrated by SAXS.