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Daniel Lopez - One of the best experts on this subject based on the ideXlab platform.
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thermo reversible hybrid gels formed from the combination of isotactic polystyrene and fe ii 4 octadecyl 1 2 4 triazole 3 clo4 2 n metallo Organic Polymer thermal and viscoelastic properties
Polymers, 2019Co-Authors: Coro Echeverria, M. A. Rubio, Daniel LopezAbstract:Nano-sized one-dimensional metallo-Organic Polymers, characterized by the phenomenon of spin transition, are excellent candidates for advanced technological applications such as optical sensors, storage, and information processing devices. However, the main drawback of this type of Polymers is their fragile mechanical properties, which hinders its processing and handling, and makes their practical use unfeasible. To overcome this problem, in this work, hybrid thermo-reversible gels are synthesized by combination of a metallo-Organic Polymer and isotactic polystyrene (iPS) in cis-decaline. A detailed investigation of the thermal and viscoelastic properties of the hybrid gels, in terms of iPS and metallo-Organic Polymer concentration is performed by means of differential scanning calorimetry and oscillatory rheology, respectively. From the analysis of the thermal properties, three transitions have been determined upon heating: Monotectic transition of the iPS gel, melting of the iPS gel, and melting of the metal-Organic Polymer gel, which suggest that the gels of the two Polymers are formed independently in the hybrid gel, as long as the two Polymers are in concentrations above the corresponding critical gelation concentrations. Results regarding viscoelastic properties and morphology confirmed that hybrid gels consisted of an interpenetrated network of Polymer gels, formed by iPS and metallo-Organic poymer gels growing independently.
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structure of a spin crossover fe ii 1 2 4 triazole Polymer complex dispersed in an isotactic polystyrene matrix
European Polymer Journal, 2011Co-Authors: M. A. Rubio, Rebeca Hernandez, Aurora Nogales, Anna Roig, Daniel LopezAbstract:Abstract Isotactic polystyrene (i-PS) was employed as a matrix to disperse a metallo-Organic Polymer of [Fe(II) (4-octadecyl-1,2,4-triazole)3(ClO4)2] in order to obtain novel functional materials exhibiting thermal spin-crossover transition. A detailed investigation of the structure of the metallo-Organic Polymer and metallo-Organic Polymer/iPS blends has been carried out by DSC, WAXD and SAXS techniques as a function of temperature and metallo-Organic Polymer/iPS proportion. The results obtained confirm on the one hand that a structural transition associated with a change in the magnetic susceptibility of the metallo-Organic Polymer is preserved in the presence of i-PS. This transition was found to be associated to both, an inter-conversion of lamellar structures into hexagonal structures and to an increase of inter-sheet distances within the lamellar structures in metallo-Organic Polymer films prepared by casting from toluene solutions. On the other hand, an increase of the degree of crystallinity of the iPS is observed in the presence of the metallo-Organic Polymer which suggests some nucleating effect of the metallo-Organic Polymer in the crystallization of isotactic polystyrene.
M. A. Rubio - One of the best experts on this subject based on the ideXlab platform.
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thermo reversible hybrid gels formed from the combination of isotactic polystyrene and fe ii 4 octadecyl 1 2 4 triazole 3 clo4 2 n metallo Organic Polymer thermal and viscoelastic properties
Polymers, 2019Co-Authors: Coro Echeverria, M. A. Rubio, Daniel LopezAbstract:Nano-sized one-dimensional metallo-Organic Polymers, characterized by the phenomenon of spin transition, are excellent candidates for advanced technological applications such as optical sensors, storage, and information processing devices. However, the main drawback of this type of Polymers is their fragile mechanical properties, which hinders its processing and handling, and makes their practical use unfeasible. To overcome this problem, in this work, hybrid thermo-reversible gels are synthesized by combination of a metallo-Organic Polymer and isotactic polystyrene (iPS) in cis-decaline. A detailed investigation of the thermal and viscoelastic properties of the hybrid gels, in terms of iPS and metallo-Organic Polymer concentration is performed by means of differential scanning calorimetry and oscillatory rheology, respectively. From the analysis of the thermal properties, three transitions have been determined upon heating: Monotectic transition of the iPS gel, melting of the iPS gel, and melting of the metal-Organic Polymer gel, which suggest that the gels of the two Polymers are formed independently in the hybrid gel, as long as the two Polymers are in concentrations above the corresponding critical gelation concentrations. Results regarding viscoelastic properties and morphology confirmed that hybrid gels consisted of an interpenetrated network of Polymer gels, formed by iPS and metallo-Organic poymer gels growing independently.
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structure of a spin crossover fe ii 1 2 4 triazole Polymer complex dispersed in an isotactic polystyrene matrix
European Polymer Journal, 2011Co-Authors: M. A. Rubio, Rebeca Hernandez, Aurora Nogales, Anna Roig, Daniel LopezAbstract:Abstract Isotactic polystyrene (i-PS) was employed as a matrix to disperse a metallo-Organic Polymer of [Fe(II) (4-octadecyl-1,2,4-triazole)3(ClO4)2] in order to obtain novel functional materials exhibiting thermal spin-crossover transition. A detailed investigation of the structure of the metallo-Organic Polymer and metallo-Organic Polymer/iPS blends has been carried out by DSC, WAXD and SAXS techniques as a function of temperature and metallo-Organic Polymer/iPS proportion. The results obtained confirm on the one hand that a structural transition associated with a change in the magnetic susceptibility of the metallo-Organic Polymer is preserved in the presence of i-PS. This transition was found to be associated to both, an inter-conversion of lamellar structures into hexagonal structures and to an increase of inter-sheet distances within the lamellar structures in metallo-Organic Polymer films prepared by casting from toluene solutions. On the other hand, an increase of the degree of crystallinity of the iPS is observed in the presence of the metallo-Organic Polymer which suggests some nucleating effect of the metallo-Organic Polymer in the crystallization of isotactic polystyrene.
Asim Bhaumik - One of the best experts on this subject based on the ideXlab platform.
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triazine based porous Organic Polymer with good co2 gas adsorption properties and an efficient organocatalyst for the one pot multicomponent condensation reaction
Chemcatchem, 2016Co-Authors: Piyali Bhanja, Sauvik Chatterjee, Asim BhaumikAbstract:A new porous Organic Polymer PDVBTT-1 (poly-divinylbenzene-co-triallyloxytriazine) has been synthesized through radical co-Polymerization utilizing two monomers, that is, divinylbenzene and 2,4,6-triallyloxy-1,3,5-triazine in the presence of AIBN (azobisisobutyronitrile) as a radical initiator under solvothermal conditions in the absence of any structure directing agent. The Polymer has been characterized thoroughly by N2 sorption, FTIR, UV/Vis, and solid-state 13C cross-polarization magic angle spinning (CP MAS) NMR spectroscopy, field emission FE-SEM, high-resolution HR-TEM, and thermogravimetric/differential thermal analysis (TG/DTA). Owing to the considerably good surface area of 644 m2 g−1 and surface basic sites (1.10 mmol g−1), the material showed very good CO2 adsorption properties. Furthermore, the porous Polymer showed good catalytic activity in the base-catalyzed, one-pot, multicomponent condensation reaction between various substituted aromatic aldehydes, malononitrile, and activated phenols such as 2-naphthol, resorcinol, etc., for the synthesis of 2-amino-chromenes in water and under solvent-free microwave irradiation conditions. This N-rich porous Polymer is highly recyclable and thus it has potential for a wide range of base-catalyzed Organic transformations in the future.
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a triazine based covalent Organic Polymer for efficient co2 adsorption
Chemical Communications, 2015Co-Authors: Ruth Gomes, Piyali Bhanja, Asim BhaumikAbstract:A new triazine functionalized hexagonally ordered covalent Organic Polymer (TRITER-1) has been synthesized via the Schiff-base condensation reaction between a tailor made triamine 1,3,5-tris-(4-aminophenyl)triazine (TAPT) and terephthaldehyde. This ordered porous Polymer showed a high BET surface area (716 m2 g−1) and an excellent CO2 uptake capacity of 58.9 wt% at 273 K under 5 bar pressure.
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a triazine functionalized porous Organic Polymer excellent co2 storage material and support for designing pd nanocatalyst for c c cross coupling reactions
Journal of Materials Chemistry, 2014Co-Authors: Arindam Modak, Malay Pramanik, Shinji Inagaki, Asim BhaumikAbstract:One-pot bottom-up synthesis involving extended aromatic electrophilic substitution on to a pyrrole has been employed for the design of a novel triazine-functionalized porphyrin-based porous Organic Polymer, TPOP-1. Hydrothermal treatment of 4,4′,4′′-(1,3,5-triazine-2,4,6-triyl)tris(oxy)tribenzaldehyde and pyrrole in glacial acetic acid in the presence of FeCl3 leads to the formation of TPOP-1, which is a highly porous and robust material, and which exhibits a high surface area and bimodal pore sizes ranging from large micropores to mesopores. The presence of porphyrin and triazine functionality within the network structure enables formation of electron-donating basic N-sites at the surface of the porous Organic framework and thus favors the adsorption of Lewis acidic CO2 molecules and decoration of the material by palladium nanoparticles at its surface to form Pd-TPOP-1. TPOP-1 showed good CO2 storage capacity (6.2 mmol g−1 or 27.3 wt% at 3 bar/273 K), suggesting its potential application in environmental clean-up. Moreover, this post Pd-functionalized material forms fine colloidal suspensions in Organic solvent and exhibits high catalytic activity for Sonogashira cross-coupling of aryl halides with aryl alkynes under mild reaction conditions.
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porphyrin based porous Organic Polymer as bi functional catalyst for selective oxidation and knoevenagel condensation reactions
Applied Catalysis A-general, 2013Co-Authors: Arindam Modak, John Mondal, Asim BhaumikAbstract:Abstract Porphyrin based microporous Organic Polymer Fe-POP-1 has been synthesized through a facile solvothermal method involving extended aromatic substitution of pyrrole and terephthaldehyde in the presence of Fe(III). This material has very high BET surface area and exhibits two types of catalytic sites: iron-free porphyrin moieties for base catalysis as well as Fe(III)-bound sites for slective oxidation reactions. Due to the presence of basic porphyrin macrocyclic site in Fe-POP-1, it catalyzes Knoevenagel condensation of aromatic aldehydes with malononitrile at room temperature, whereas the Fe(III)-bound site catalyzes selective oxidation of alcohols to the respective aldehyde/ketones in the presence of tert -butyl hydroperoxide (TBHP) as oxidant. Good reusability and excellent selectivity makes this Fe-POP-1 as a promising and efficient bi-functional heterogeneous catalyst for the production of Organic fine chemicals through the environmentally benign liquid phase catalytic reactions.
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porphyrin based porous Organic Polymer supported iron iii catalyst for efficient aerobic oxidation of 5 hydroxymethyl furfural into 2 5 furandicarboxylic acid
Journal of Catalysis, 2013Co-Authors: Basudeb Saha, Arindam Modak, Dinesh Gupta, Mahdi M Abuomar, Asim BhaumikAbstract:Abstract Environmentally friendly and efficient synthesis of 2,5-furandicarboxylic acid (FDCA), a polyester building block chemical from biomass, was carried out in water by aerobic oxidation of 5-hydroxymethylfurfural (HMF) with highly cross-linked, robust structured, and thermally stable Fe III –porous Organic Polymer (Fe III –POP-1) material containing basic porphyrin subunits and iron metal center. EPR analysis confirmed that the catalyst retained the oxidation state of Fe(III) after catalysis and can be reused.
Coro Echeverria - One of the best experts on this subject based on the ideXlab platform.
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thermo reversible hybrid gels formed from the combination of isotactic polystyrene and fe ii 4 octadecyl 1 2 4 triazole 3 clo4 2 n metallo Organic Polymer thermal and viscoelastic properties
Polymers, 2019Co-Authors: Coro Echeverria, M. A. Rubio, Daniel LopezAbstract:Nano-sized one-dimensional metallo-Organic Polymers, characterized by the phenomenon of spin transition, are excellent candidates for advanced technological applications such as optical sensors, storage, and information processing devices. However, the main drawback of this type of Polymers is their fragile mechanical properties, which hinders its processing and handling, and makes their practical use unfeasible. To overcome this problem, in this work, hybrid thermo-reversible gels are synthesized by combination of a metallo-Organic Polymer and isotactic polystyrene (iPS) in cis-decaline. A detailed investigation of the thermal and viscoelastic properties of the hybrid gels, in terms of iPS and metallo-Organic Polymer concentration is performed by means of differential scanning calorimetry and oscillatory rheology, respectively. From the analysis of the thermal properties, three transitions have been determined upon heating: Monotectic transition of the iPS gel, melting of the iPS gel, and melting of the metal-Organic Polymer gel, which suggest that the gels of the two Polymers are formed independently in the hybrid gel, as long as the two Polymers are in concentrations above the corresponding critical gelation concentrations. Results regarding viscoelastic properties and morphology confirmed that hybrid gels consisted of an interpenetrated network of Polymer gels, formed by iPS and metallo-Organic poymer gels growing independently.
Qiang Miao - One of the best experts on this subject based on the ideXlab platform.
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a series of novel types of immobilized chiral salen mn iii on different Organic Polymer inOrganic hybrid crystalline zinc phosphonate phosphate act as catalysts for asymmetric epoxidation of unfunctionalized olefins
Catalysis Science & Technology, 2012Co-Authors: Jing Huang, Gang Wang, Qiang MiaoAbstract:A novel type of layered crystalline Organic Polymer-inOrganic hybrid material, zinc poly(styrene-phenylvinylphosphonate)-phosphate (ZnPS-PVPA) was synthesized and an array of new heterogeneous catalysts were gained by grafting chiral salen Mn(III) onto the ZnPS-PVPA, and characterized by FT-IR, diffusion reflection UV-vis, AAS, N2 volumetric adsorption, SEM, TEM, XPS, XRD and TG. The immobilized chiral salen Mn(III) catalysts exhibited higher chiral induction in the asymmetric epoxidation of α-methylstyrene and indene with m-CPBA and NaIO4 as oxidants than the corresponding homogeneous catalyst did (ee, >99% vs. 54% and >99% vs. 65%). And the heterogeneous catalysts are relatively stable and can be recycled nine times in the asymmetric epoxidation of α-methylstyrene. Furthermore, this novel type of catalyst can also be efficiently used in large-scale reactions with superior catalytic ability being maintained at the same level, which possessed the potentiality for application in industry.
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catalytic asymmetric epoxidation of unfunctionalized olefins using a series novel type of layered crystalline Organic Polymer inOrganic hybrid zinc phosphonate phosphate immobilized aryldiamine modified chiral salen mn iii complex
Applied Catalysis A-general, 2011Co-Authors: Jing Huang, Qiang MiaoAbstract:Abstract In this report we demonstrate the suitability of layered crystalline Organic Polymer–inOrganic hybrid material ZnPS–PVPA with different content of the Organic group and different inOrganic phosphate as catalyst supports for asymmetric catalysis. A series of the chiral salen Mn(III) complex immobilized onto ZnPS–PVPA modified by aryldiamine were synthesized and characterized by FT-IR, diffusion reflection UV–vis, AAS, N 2 volumetric adsorption, SEM, TEM, XRD and TG. The supported catalysts displayed superior catalytic activities in the asymmetric epoxidation of α-methylstyrene and indene with m-CPBA and NaIO 4 as oxidants, compared with the corresponding homogeneous catalyst ( ee , >99% vs 54% and >99% vs 65%). And the heterogeneous catalysts are relatively stable and can be recycled nine times in the asymmetric epoxidation of α-methylstyrene. These results revealed that the special structure of ZnPS–PVPA played vital impacts on the conversion and enantioselectivity. Furthermore, this novel type of catalyst can also be validly used in large-scale reactions with superior catalytic disposition being maintained at the same level, which possessed the potentiality for application in industry.