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SYNTHESIS AND CHARACTERIZATION OF POLY[3-(2\',5\'-DIHEPTYLOXY- PHENYL)THIOPHENE] FOR USE IN PHOTOELECTROCHEMICAL CELLS
Assefa Sergawie, Shimelis Admassie, Wendimagegn Mammo, Teketel Yohannes, Theodros Solomon
Bulletin of the Chemical Society of Ethiopia , 2007,
Abstract: Poly[3-(2\',5\'-diheptyloxyphenyl)thiophene], PDHOPT, has been prepared electrochemically from its monomer for solar cell application. PDHOPT exhibits a band gap of 2.1 eV. The redox properties of PDHOPT were characterized using cyclic voltammetry. The estimated energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are -5.3 eV and -3.2 eV, respectively. PDHOPT sensitizes nanocrystalline titanium dioxide (nc-TiO2) in liquid-state photoelectrochemical cells. Devices where the photoactive electrode consists of nc-TiO2/PDHOPT composite film show improved performance over those that consist of only PDHOPT. Devices made of TiO2/PDHOPT composite film produced an open-circuit voltage of 0.52 V, a short-circuit current of 29 μA/cm2, and a fill factor of 0.54 when illuminated with white light intensity of 80 mW/cm2. KEY WORDS: Liquid-state photoelectrochemical cell, Nanocrystalline titanium dioxide, PDHOPT, I3-/I- redox couple Bull. Chem. Soc. Ethiop. 2007, 21(3), 405-417.
Synthesis and characterization of poly[3-(2’,5’-diheptyloxy-phenyl)thiophene] for use in photoelectrochemical cells  [cached]
Assefa Sergawie,Shimelis Admassie,Wendimagegn Mammo,Teketel Yohannes
Bulletin of the Chemical Society of Ethiopia , 2007,
Abstract: Poly[3-(2',5'-diheptyloxyphenyl)thiophene], PDHOPT, has been prepared electrochemically from its monomer for solar cell application. PDHOPT exhibits a band gap of 2.1 eV. The redox properties of PDHOPT were characterized using cyclic voltammetry. The estimated energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are -5.3 eV and -3.2 eV, respectively. PDHOPT sensitizes nanocrystalline titanium dioxide (nc-TiO2) in liquid-state photoelectrochemical cells. Devices where the photoactive electrode consists of nc-TiO2/PDHOPT composite film show improved performance over those that consist of only PDHOPT. Devices made of TiO2/PDHOPT composite film produced an open-circuit voltage of 0.52 V, a short-circuit current of 29 μA/cm2, and a fill factor of 0.54 when illuminated with white light intensity of 80 mW/cm2.
Synthesis and optical properties of poly[(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] with 1,8-naphthalimide end group
ZhengNeng Jin,QingFeng Xu,JianMei Lu,Feng Yan,XueWei Xia,LiHua Wang,NaJun Li
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-008-0539-3
Abstract: A series of homopolymers, poly[(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] (NAPH-PMABEs) containing benzoxazole side chain and 1,8-naphthalimide end group, were prepared by atom transfer radical polymerization (ATRP) and end-group modification. The structure of NAPH-PMABE was characterized by GPC, 1H-NMR and UV-vis spectra. The polymer has good solubility in common organic solvents, such as dichloromethane (CH2Cl2), tetrahydrofuran (THF), N,N-dimethylformamide (DMF), chloroform (CHCl3), acetone and toluene. The optical properties of NAPH-PMABE were investigated. Results show that NAPH-PMABE has a composite emission spectrum comprising an ultraviolet component originating from benzoxazole side chains and a green component originating from 1,8-naphthalimide end group in both solution and film. The intensity of the two emission bands can be easily tuned by changing molecular weight.
Synthesis and optical properties of poly[(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] with 1,8-naphthalimide end group

ZhengNeng Jin,QingFeng Xu,JianMei Lu,Feng Yan,XueWei Xia,LiHua Wang,NaJun Li,

科学通报(英文版) , 2009,
Abstract: A series of homopolymers, poly(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] (NAPH-PMABEs) containing benzoxazole side chain and 1,8-naphthalimide end group, were prepared by atom transfer radical polymerization (ATRP) and end-group modification. The structure of NAPH-PMABE was characterized by GPC, 1H-NMR and UV-vis spectra. The polymer has good solubility in common organic solvents, such as dichloromethane (CH2Cl2), tetrahydrofuran (THF), N,N-dimethylformamide (DMF), chloroform (CHCl3), acetone and toluene. The optical properties of NAPH-PMABE were investigated. Results show that NAPH-PMABE has a composite emission spectrum comprising an ultraviolet component originating from benzoxazole side chains and a green component originating from 1,8-naphthalimide end group in both solution and film. The intensity of the two emission bands can be easily tuned by changing molecular weight. Supported by National Natural Science Foundation of China (Grant Nos. 20476066 and 20571054), Science and Technology Project in Suzhou, China (Grant No. SG0718), and Project of High Technology of Jiangsu Province, China (Grant No. BG2005021)
SILICON-CONTAINING AROMATIC POLY(ESTERS) DERIVED FROM BIS(4-CARBOXYPHENYL)METHYL-R-SILANE AND BIS(4-(HYDROXYMETHYL) PHENYL)METHYL-R-SILANE: SYNTHESIS, CHARACTERIZATION AND THERMAL STUDIES
TAGLE,LUISH; TERRAZA,CLAUDIO A; PINO,LEONARDO I;
Journal of the Chilean Chemical Society , 2012, DOI: 10.4067/S0717-97072012000200023
Abstract: this work describes the synthesis, characterization and thermal studies of poly(esters) (pes) containing two si atoms in the main chain, derived from aromatic diacids and aliphatic dialcohols in which the si atom is bonded to methyl and/or ethyl groups. pes were characterized by ft-ir and 1h, 13c and 29si spectroscopy and the results were in agreement with the proposed structures. poly(esters) were soluble in polar aprotic solvents, such as dmso and dmf, and acetone, and partially soluble in ethanol. the inherent viscosity and glass transition and thermal decomposition temperatures, hinh, tg and tdt respectively, were determined. these results showed that pe-2 and pe-4, derived from the dialcohol with the -si(ch3)(ch2ch3)- moiety as central element, had the larger values of hinh, tg, tdt and the residual weight after heating at 900 °c, indicating that the specific structure of aliphatic dialcohols control the reaction.
SILICON-CONTAINING AROMATIC POLY(ESTERS) DERIVED FROM BIS(4-CARBOXYPHENYL)METHYL-R-SILANE AND BIS(4-(HYDROXYMETHYL) PHENYL)METHYL-R-SILANE: SYNTHESIS, CHARACTERIZATION AND THERMAL STUDIES  [cached]
LUISH TAGLE,CLAUDIO A TERRAZA,LEONARDO I PINO
Journal of the Chilean Chemical Society , 2012,
Abstract: This work describes the synthesis, characterization and thermal studies of poly(esters) (PEs) containing two Si atoms in the main chain, derived from aromatic diacids and aliphatic dialcohols in which the Si atom is bonded to methyl and/or ethyl groups. PEs were characterized by FT-IR and 1H, 13C and 29Si spectroscopy and the results were in agreement with the proposed structures. Poly(esters) were soluble in polar aprotic solvents, such as DMSO and DMF, and acetone, and partially soluble in ethanol. The inherent viscosity and glass transition and thermal decomposition temperatures, h inh, Tg and TDT respectively, were determined. These results showed that PE-2 and PE-4, derived from the dialcohol with the -Si(CH3)(CH2CH3)- moiety as central element, had the larger values of h inh, Tg, TDT and the residual weight after heating at 900 °C, indicating that the specific structure of aliphatic dialcohols control the reaction.
Synthesis of thermoplastic poly(ester-olefin) elastomers
Tanasijevi? Branka,Elkhaseh Salem F.K.,Nikoli? Marija S.,?onlagi? Jasna A.
Hemijska Industrija , 2004, DOI: 10.2298/hemind0410444t
Abstract: A series of thermoplastic poly(ester-olefin) elastomers, based on poly(ethylene-stat-butylene), HO-PEB-OH, as the soft segment and poly (butylene terephthalate), PBT, as the hard segment, were synthesized by a catalyzed transesterification reaction in solution. The incorporation of soft hydrogenated poly(butadiene) segments into the copolyester backbone was accomplished by the polycondensation of α, ω-dihydroxyl telechelic HO-PEB-OH, (PEB Mn = 3092 g/mol) with 1,4-butanediol (BD) and dimethyl terephthalate (DMT) in the presence of a 50 wt-% high boiling solvent i.e., 1,2,4-trichlorobenzene. The molar ratio of the starting comonomers was selected to result in a constant hard to soft weight ratio of 60:40. The synthesis was optimized in terms of both the concentration of catalyst, tetra-n-butyl-titanate (Ti(OBu)4), and stabilizer, N,N'-diphenyl-p-phenylenediamine (DPPD), as well as the reaction time. It was found that the optimal catalyst concentration (Ti(OBu)4) for the synthesis of these thermoplastic elastomers was 1.0 mmol/mol ester and the optimal DPPD concentration was 1.0 wt-%. The extent of the reaction was followed by measuring the inherent viscosity of the reaction mixture. The effectiveness of the incorporation of the soft segments into the copolymer chains was proved by Soxhlet extraction with chloroform. The molecular structures, composition and the size of the synthesized poly(ester-butylene)s were verified by 1H NMR spectroscopy, viscometry of dilute solutions and the complex dynamic melt viscosity. The thermal properties of poly(ester-olefin)s were investigated by differential scanning calorimetry (DSC). The degree of crystallinity was also determined by DSC. The thermal and thermo-oxidative stability were investigated by thermogravimetric analysis (TGA). The rheological properties of poly(ester-olefin)s were investigated by dynamic mechanical spectroscopy in the melt and solid state.
Synthesis, characterization and photopolymerization of vinyl functionalized poly (ε-caprolactone)
eXPRESS Polymer Letters , 2009, DOI: 10.3144/expresspolymlett.2009.21
Abstract: Vinyl functionalized poly (ε-caprolactone) with molar mass ranging from 500–5000 Da were synthesized by ring opening polymerization and further photopolymerized. One-step synthesis and functionalization is achieved based on ring opening polymerization (ROP). Hydroxyl butyl vinyl ether (HBVE) was employed to play the role as the initiator of ROP, and photo-curable functional group. The presence of CH2=CH peak in Fourier Transform Infrared (FTIR) spectra confirmed that vinyl end groups were successfully attached to poly (ε-caprolactone) (PCL) macromolecule. Kinetic parameters of cationic photopolymerization of vinyl functionalized PCL were investigated. The activation energy was estimated at 11.33 kJ/mol, by assuming the cationic system followed second-order autocatalytic model.
Synthesis of thermoplastic poly(ester-siloxane)s in the melt and in solution
BILJANA P. DOJCINOVIC,VESNA V. ANTIC,MARIJA V. VUCKOVIC,JASNA DJONLAGIC
Journal of the Serbian Chemical Society , 2005,
Abstract: Two series of thermoplastic elastomers, based on poly(dimethylsiloxane), PDMS, as the soft segment and poly(butylene terephthalate), PBT, as the hard segment, were synthesized by catalyzed transesterification, from dimethyl terephthalate, DMT, silanol-terminated poly(dimethylsiloxane), PDMS-OH, Mn = 1750 g/mol, and 1,4-butanediol, BD. The mole ratio of the starting comonomers was selected to result in a constant hard to soft weight ratio of 55:45. The first series was synthesized in order to determine the optimal mole ratio of BD and DMT for the synthesis of high molecular weight thermoplastic poly(ester-siloxane)s, TPESs. The second series was performed in the presence of the high-boiling solvent, 1,2,4-trichlorbenzene in order to increase the mixing between the extremely non-polar siloxane prepolymer and the polar reactants, DMT and BD, and, therefore, avoid phase separation during synthesis. The structure and composition of the synthesized poly(ester- siloxane)s were verified by 1H-NMR spectroscopy, while the melting temperatures and degree of crystallinity were determined by differential scanning calorimetry (DSC). The effectiveness of the incorporation of the silanol-terminated poly( dimethylsiloxane) into the polyester chains was verified by chloroform extraction. The rheological properties of the poly(ester-siloxane)s were investigated by dynamic mechanical spectroscopy (DMA).
Application of reactive siloxane prepolymers for the synthesis of thermoplastic poly(ester–siloxane)s and poly(ester–ether–siloxane)s
VESNA V. ANTIC,MARIJA V. VUCKOVIC,JASNA DJONLAGIC
Journal of the Serbian Chemical Society , 2007,
Abstract: Thermoplastic poly(ester–siloxane)s (TPES) and poly(ester–ether–siloxane) s, (TPEES), based on poly(butylene terephthalate) (PBT) as the hard segment and different siloxane-prepolymers as the soft segments, were prepared. The TPES and TPEES were synthesized by catalyzed two-step transesterification from dimethyl terephthalate, (DMT), 1,4-butanediol, (BD) and a siloxane-prepolymer. Incorporation of dicarboxypropyl- or disilanol-terminated poly(dimethylsiloxane)s (PDMS) into the polar poly(butylene terephthalate) chains resulted in rather inhomogeneous TPES copolymers, which was a consequence of a prononuced phase separation of the polar and non-polar reactants during synthesis. Two concepts were employed to avoid or reduce phase separation: 1) the use of siloxane-containing triblock prepolymers with hydrophilic terminal blocks, such as ethylene oxide (EO), poly(propylene oxide) (PPO) or poly(caprolactone) (PLC) when the terminal blocks serve as a compatibilizer between the extremely non-polar PDMS and the polar DMT and BD, and 2) the use of a high-boiling solvent (1,2,4-trichlorobenzene) during the first phase of the reaction. Homogeneity was significantly improved in the case of copolymers based on PCL–PDMS–PCL.
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