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The Sulfonated Poly(arylene ether)s for Fuel CellWu, Sheng-feng 06 September 2010 (has links)
PEM (Proton Exchange Membrane) fuel cell is one of the most important green energy, because it has high energy density, lifetime, small and light.etc advantages. Nafion , the major material for PEM now, However, has some disadvantages such as high cost ($600¡V1000/m2) and limited choices for operation temperature about 25¢J~80¢J. Consequently, there is an increasing interest in the development of alternative ionomer membranes with lower cost, and higher proton conductivity, and that are more easily processed. Here we present polymeric membranes made of sulfonic Poly(arylene ether)s (PAEs) which is achieved by nucleophilic displacement reactions of dihalo or dinitro compounds with alkali metal bisphenolates and direct polymer sulfonation was carried out in heterogeneous media using chlorosulfonic acid as both solvent and sulfonating agent. In our PAEs which has high Tg values about 225¡ã250¢XC depends on the barriers to rotation along the main polymer chain. And weight losses above 500 ¢XC by thermogravimetric (TGA) analysis, indicative of their high thermal stability.
After FTIR analysis we preparation sulfonated polymer successfully by using chlorosulfonic acid as sulfonating agent. Thermogravimetric analysis (TGA) studies were carried out to investigate the thermal stability of sulfonated PAEs (Td≈ 500¢XC). The proton conductivity of polymer s(DFB+M3) sulfonated with chlorosulfonic acid about 10-6¡ã10-7S cm-1 .Compared with Nafion membrane measured in the same condition, the conductivity of our membrane is smaller than 3~4 order. In the future, it is possible to improve the conductivity of our membrane with optimization.
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Preparation and Study of Electro-Optical Properties of Novel Flexible Substrate MaterialsHuang, Kuan-lung 29 July 2008 (has links)
Monomer 4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦-bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦,5¡¦¡¦,6¡¦¡¦-triphenyl (M4) were converted to novel poly(arylene ether)s by nucleophilic displacement reaction with several bisphenols in this study, then we called them : P-A1, P-A2, P-B1, P-B2. These polymers exhibit weightaverage molecular weight (Mw) between 2.2¡Ñ10^4 to 2.2¡Ñ10^5 g/mol. The molecular weight were investigated and confirmed by Mass and GPC. The molecular structures were investigated and confirmed by NMR and FT-IR.Thermal analysis physics studies with these polymers confirmed by Thermogravimetric analyzer (TGA) and differential scanning calorimetry (DSC). It is indicated that Td 5% of these polymers were 450¢XC ~ 548¢XC in TGA and Tg of these polymers were 303¢XC ~ 324¢XC in DSC.Besides, these polymers not were observed apparent crystallizing point, so we consider that they are not easy crystallized. Therefore, they could make manufacture in higher temperature and have higher thermal stability.In photophysical property of polymeric thin films, we obtained absorption wavelength that was 232nm ~ 300nm in UV-Vis absorption spectra and excitation wavelength that was 362nm ~ 368nm in PL spectra. Furthermore, the transmission spectra of polymeric thin films showed that visible light transparency were up to 83%. Besides, we used Ellipsometer to measure refractive index(n) that is 1.33 ~ 1.49.In drop shape analysis system, contact angles of the polymeric thin films are more than 109.8¢X. They show that the polymer thin films have low polarity and good hydrophobicity. By above material properties of these polymers, they have high thermal stabilities, high optical transparency, low polarity and good hydrophobicity. These good material properties are doing as a plastic substrate of devices or panel display.
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Physical and Electro-Optical Characterization and Application of Novel Poly(arylene ether)s with High Tg¡¦sTsao, Tzu-i 27 July 2007 (has links)
There are three novel 2-trifluoromethyl-activated bisfluoro monomers have been successfully synthesized in this study, and the nomenclatures are shown as follows:
4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦-bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦,5¡¦¡¦,6¡¦¡¦-triphenyl(M4),
4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦-bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦,5¡¦¡¦-triphenyl(M3),
4,4¡¦¡¦¡¦¡¦-Difluore-3,3¡¦¡¦¡¦¡¦-bis(trifluoromethyl)-2¡¦¡¦,3¡¦¡¦-triphenyl(M2). Through polymerization with 1,1-dihydroxydiphenyl cyclododecane the monomers M2, M3 and M4 were accordingly converted into poly(arylene ether)s P2-1,1C, P3-1,1C and P4-1,1C, respectively. These polymers exhibit weight-average molecular weight up to 2.25¡Ñ105g/mol. The molecular weight were investigated and confirmed by MASS and GPC. The molecular structures were investigated and confirmed by NMR and FTIR.
The UV-VIS absorption and photoluminescence spectra measurement of all the monomers and polymers in dilute solutions and in solid state were conducted. The results show that all monomers and polymers in dilute solutions have no absorption in the vision light region of spectrum. The absorption spectra of polymer thin films showed high optical transparency up to 90%. The photoluminescence spectra of all monomers and polymers in dilute solutions and thin film emits light with high intensity and wavelength in region of 350~380nm.
Thermal analysis studies were conducted with TGA, DSC, TMA and crystal property study was performed by XRD. The results show that these polymers did not show melting but showed ultrahigh Tg values ranging from 270~330¢XC in DSC and TMA measurements, so it indicated that three polymers were not crystalline materials. Outstanding thermal stability is over then 440~ 460¢XC for 5% weight loss in TGA under nitrogen atmosphere. So it could make manufacture in higher temperature and have higher thermal stability.
With optical properties of polymer thin films, we utilized Ellipsometer to measure refractive index and the results showed no birefringence for these polymers. The polymer thin films show low polarity and high hydrophobicity could be attested by the measured results of contact angle and surface energy.
The HOMO and LUMO energy level of monomers are both measured by Cyclic Voltammetry and theoretical calculation.
The absorption spectra of polymer thin films showed no absorption in the visible light region of the spectrum i.e., having a high optical transparency. All above stated material properties are good for doing as a plastic substrate of devices or panel display.
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Application of Organic Optoelectronic Materials and Flexible ElectronicsLee, Chun-Che 14 December 2010 (has links)
We proposed a flexible electronics with functional poly (arylene ether)s and discotic liquid crystal. Firstly, we provided a series of the PAE polymer with remarkable thermal stability and high optical transmittance. The PAEs were synthesized via nucleophilic displacement as polymerization on a 2-trifluoromethyl-activated bisfluoro monomer, which reacted with bisphenols. Thermal analysis indicated the PAEs possessed a high glass transition point of ~300¢J and the decomposition temperature Td=500¢J at a weight loss of 5%. Additionally, high transmittance of 85%, low dielectric constant of ~2.0, and well mechanical property of the PAE films were experimentally verified, as a high potential substrate for flexible electronics. Two kind of device structure has been prepared, were organic thin film solar cell and Dye sensitized solar cell. Furthermore, we provided the self-assembled triphenylene-based liquid crystal and its polymer derivative to apply for photovoltics. The 2, 3, 6, 7-tetra-6-octyloxydibenzo[a,c]phenazine-11-carboxylic group and the polymer of merging with disc-unit and polyacrylamide. Both show a highly isotropic phase transition point of ~270¢J and the decomposition temperature Td~450¢J at a weight loss of 5%. The specific absorption in visible light region was at 200 - 450 nm. A distinct self-arrangement of columnar array was investigated by optical textures. The self-arranged pathway enhanced carrier mobility due to £k-£k conjugation in hexagonal column stacking. Finally, the PAEs and DLC materials applied to thin film solar cell (ITO/PEDOT:PSS/DLC-PAM/P3HT:PCBM/Al) as hole transporting layer. The photo-conversion efficiency was strong depending on organic compounds, such as molecular structure, photo-physic and chemical properties. On the basis of integrated characteristics, it suggested a high potential as flexible electronics for photovoltics.
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Preparation and Characterization of Poly(aryl ether)s Containing Novel Bisphenol Monomers in Flexible SubstrateJuan, Fan-Shuan 07 July 2011 (has links)
In this research that we design in the polymer structure containing the core monomer into benzene ring structure for appied on the flexible substrate and the optoelectronic components .Three novel bisphenol monomers have been synthesised successfully and converted to a series of poly(arylene ether)s by nucleophilic displacement reaction with Bis(4-fluorophenyl) sulfone, then we called them:P1, P2 and P3.We can see from the material structure that the steric hindrance of the group connected to the side of the main chain (M2) is larger than the group in the main chain(M1,M3),and the steric hindrance of the longer length of main chain (M3) is smaller than the shorter one(M1) in the polymerization Thermal analysis physics studies with these polymers confirmed by Thermogravimetric analyzer(TGA) and differential scanning calorimetry (DSC).It is indicated that Td5% of these polymers were 476¢XC~577¢XC in TGA and Tg of these polymers were 264¢XC~290¢XC in DSC. Besides, these polymers were not observed apparent crystallizing point, so we consider that they are not crystallized easily. The transmission spectra of thin film in the visible light region were up to 87%~93%. In drop shape analysis system, the contact angles of them are 85¢X~87¢X, show that they have good hyrophobicity.By above material properties of these polymers, they have high thermal stabilities, high optical transparency and good hydrophobicity.
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Synthesis Of Novel Blue-emitting Poly(arylene ether)s with Application to Light Emitting DiodesChang, Ming-sian 19 July 2012 (has links)
In this thesis, a novel blue Poly (arylene ether) s polymer was prepared for the organic polymer light emitting diodes which was composed of the main material anthracene difluoro monomer derivatives, and object material of triphenylamine with the extension structure similar to the literature seen BD-1 asymmetric derivatives, as the hole transport material of carbazole of the diol derivatives. In general, Anthracene derivatives and BD-1, often seen in the literature as the host, guest blue polymer doping, the main use to Forster energy transfer to transfer energy to the guest, so it has good luminous efficiency. Anthracene, flat Good, easy to crystallization during evaporation, resulting in leakage generated; and the deposition of the multilayer structure will hinder charge injection to the emitting layer. From the angle of the molecular design of this study. (1) Use of the CF bond and Carbazole increase the steric hindrance of the polymer chain and change by fluoride compounds of the highest occupied molecular orbital - lowest unoccupied molecular orbital energy level. (2) The hole transport layer to import into the emitting layer. The two monomers Anthracene derivatives fluoride monomer the Carbazole of diol derivatives via nucleophilic polycondensation synthesis of a novel in proper proportion, Blue polymer.
Component parts, the Blue poly aromatic ether polymer doped with a small amount of blue light-emitting guest as a component layer of the component structure: ITO / PEDOT: PSS / emitting layer / LiF / Al light-emitting layer can make use of spin coating of solvent process, and its advantage is the convenience of the process and a large area. The undoped guest before the Blue polymer production the PLED starting voltage can be reduced to 4.5 V, and maximum brightness 7 466 cd/m2, efficiency as high as 4.2 cd / A. C.I.E. coordinates of (0.15,0.08), very close to the official regulations of the NTSC Blue coordinates (0.14,0.08). When doped with 3% of the guest, the starting voltage can be reduced to 4.5 V, maximum brightness of 12104 cd/m2 and efficiency as high as 5.79 cd/A.
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Locally and Densely Sulfonated Poly(arylene ether)s as Proton Exchange MembraneTang, Kai-Chun 20 July 2012 (has links)
The proton exchange membrane fuel cells should have three major advantages: 1. micro-phase separation, 2. mechanical properties and 3. thermal stability. According to the recent literature and the material of core benzene ring poly (arylene ether)s studied by our group, this paper synthesize a series of the locally and densely sulfonated polymer. We use core benzene ring as the diol monomer and the containing CF3 groups as the fluorine monomer to synthesis poly (arylene ether)s via nucleophilic displacement reactions, and then use the different concentrations synthesized sulfonated polymer by sulfonic acid reaction.
According to NMR¡¦s result we confirmed that the structure of synthetic materials is correct. By using GPC we get that the KP1, KP2, and KP3¡¦s molecular weight about 20000 (g/mol) ; The thermal stability up to 530OC for 5% loss in TGA under nithtrogen, to prove thisseries of polymer excellent thermal stability. After sulfonation, SKP1, SKP2 and SKP3¡¦s decomposition temperature decreased about 200OC ~ 250OC ranging with increasing degree of sulfonation. By DSC analysis, K1, K2 and K3 monomer's Tg followed up with the increase of the benzene ring number, however, the polymer does not have any apparent peak.
About the Proton conductive, SKP2C IEC 2.23mequiv / g, water uptake 94%, the highest proton conductivity can be as high as 68.2 mS / cm, has been similar to Nafion 117 of 70 mS / cm.
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Synthesis and Application of Poly(arylene ether)s for Proton Exchange MembraneChu, Meng-Han 21 July 2012 (has links)
Proton Exchange Membrane Fuel Cell has the potential to become an important energy conversion technigne. Lots of efforts oriented toward the electrochemical conversion of energy using proton exchange membrane (PEM) fuel cells have been enormously accelerated with the hope to promote as an alternative power source for transport and portable purposes. However, they still suffer from such disadvantages as limited operation temperature, high cost, insufficient durability and high methanol permeability.Good membranes should meet several strict requirements as follows; reasonable proton conductivity, high stability and durny the performance of a fuel cell environment,outstanding mechanical toughness, high heat endurance, and impermeability to fuel gas or liquid. Presently,a lot of references have mentioned some sulfonatied polymer sulfonated of poly(ether ether ketone) (SPEEK), sulfonatedpolysulfone (SPSF), sulfonated polysulfide sulfone(SPSS), and polybenzimidazole(PBI) and so on.To achieve high proton conductivity usually match with a high degree of sulfonation that means owning a large Ion Exchange Capacity, IEC.But which in turn leads to a decrease in the electrochemical¡Bdimensional stability¡Bwater uptake¡Boxidative stability.
Therefore they suffer from such disadvantages as limited operation range of temperature.Three aromatic poly(arylene ether)s P4b¡BP4c¡BP4d were synthesized from the polymer consists nine of polyaromatic groups with bisfluoride monomer at studying long time in our laboratory with S1¡BS2¡BS3 diol monomer.The molecular weight of the polymer (Mw:1.49¡Ñ105~5.3¡Ñ105 g/mol ,PDI: 1.82~2)This polymer has high strength,thermal stability and all of polymers own very high Td ,which are over than 500oC.We sulfonatied the polymer in order to apply as the proton exchange membrane of a fuel cell.The results showed after sulfonation of P4b¡BP4c¡BP4d.All IEC reaches 3.9~1(meq/g).According to above result, we propose the aromatic poly(arylene ether)s is good matenal can be used on all application as a proton exchange membrane.
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