Browsing by Author "Cheng, Chih-Chia"

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A "Plug and Play" polymer through biocomplementary hydrogen bonding
(2008-10-01)
Cheng, Chih-Chia
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Huang, Chih-Feng
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Yen, Ying-Chieh
;
Chang, Feng-Chih
;
應用化學系
This article describes a DNA-like polymer that exhibits the ability to self-assemble through hydrogen bonding. We synthesized poly[1-(4-vinylbenzyl)thymine] (PVBT) and 9-bexadecyladenine (A-C16) through an atom transfer radical polymerization (ATRP) and alkylation, respectively. Biocomplementary PVBT/A-C16 hierarchical supramolecular complexes formed in dilute DMSO solution through nucleobase recognition, that is, hydrogen bonding interactions between the thymine (T) groups of PVBT and the adenine (A) group of A-C16; evidence for this molecular recognition was also gained from dynamic light scattering studies. H-1 NMR titration studies in CDCl3 showed that T-A complexes formed rapidly on the NMR time scale with high association constants (up to 534 M-1). Moreover, FTIR spectroscopic, differential scanning calorimetry, wide-angle X-ray diffraction, and small-angle X-ray scattering analyses provided further details into the nature of the self-assembly of these systems. In the bulk state, these complexes self-assemble into well-ordered lamellar structures; the changing d-spacing distance (ranging from 4.98 to 2.32 nm) at different A-C16 loadings reveals that the molecular structures of the PVBT/A-C16 complexes are readily tailored. (C) 2008 Wiley Periodicals, Inc.
A new benzoxazine containing uracil, complementary functionality
(2011)
Yen, Ying-Chieh
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Cheng, Chih-Chia
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Chu, Yu-Lin
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Chang, Feng-Chih
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應用化學系
A new benzoxazine, uracil containing benzoxazine (UBz), has been successfully synthesized. The FTIR and DSC measurement of the poly(UBz)/poly(BA-a) blends indicated that hydrogen bonding interactions between uracil groups would result in a decrease in the exothermic peak temperature. In addition, the PL measurement confirmed that the poly(UBz)/poly(BA-a) blend possessed complementary behavior.
A new organic/inorganic electroluminescent material with a silsesquioxane core
(2009-04-01)
Cheng, Chih-Chia
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Chien, Chen-Han
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Yen, Ying-Chieh
;
Ye, Yun-Sheng
;
Ko, Fu-Hsiang
This paper describes a new polyhedral oligomeric silsesquioxane (POSS)-based blue-light electroluminescent nanoparticle, octakis[N-(9-ethyl-9-H-carbazol-3-yl)undecanamide-11-dimethylsiloxy]silsesquioxane (POSS-C11-Cz), which contains eight carbazole chromophore arms, synthesized through the hydrosilation reaction of octakis(dimethylsiloxy)silsesquioxane with the terminal olefin Cz-C11ene. POSS-C11-Cz exhibits good thermal and electrochemical stabilities and good film-forming properties. The optical and photoluminescence spectra of POSS-C11-Cz in solution and in the solid state indicate a reduction in the degrees of aggregation and excimer formation because inter-chain interactions were prohibited by the bulky POSS core. Moreover, photoluminescence spectra of a POSS-C11-Cz (3 wt.%,)/polyfluorene (97 blend revealed that the color was stable after heating the sample at 200 degrees C for 5 h; in contrast, the pure polyfluorene exhibited a significant green emission at 530 nm. A triple-layer device based on this blend exhibited higher maximum brightness and luminance efficiencies relative to those of the pure polyfluorene. Thus, the organic/inorganic POSS-C11-Cz/polyfluorene blend has potential for use in polymeric light-emitting diodes because of its improved thermal and optoelectronic characteristics. Published by Elsevier Ltd on behalf of Acta Materialia Inc.
A New Poly(amide urethane) Solid State Electrolyte Containing Supramolecular Structure
(2010-03-09)
Yen, Ying-Chieh
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Cheng, Chih-Chia
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Kuo, Shiao-Wei
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Chang, Feng-Chih
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應用化學系
A new supramolecular film formed from a silsesquioxane derivative for application in proton exchange membranes
(2012-01-14)
Cheng, Chih-Chia
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Yen, Ying-Chieh
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Ko, Fu-Hsiang
;
Chu, Chih-Wei
;
Fan, Shih-Kang
A new polyhedral oligomeric silsesquioxane ionomer (HO-doped PUSS-C11-Py) has been investigated. This new ionomer is able to self-assemble through macromers by quadruple hydrogen bonding interactions into a physically crosslinked polymer-like material that can be easily fabricated into films with micro-phase separation. This HCl-doped POSS-C11-Py membrane exhibits higher proton conductivity than a typical Nafion membrane at high temperature, which is extremely rare for a non-sulfonic acid system. This newly developed material may provide an alternative route toward design and fabrication of a new type of proton exchange membranes.
A New Supramolecular Hole Injection/Transport Material on Conducting Polymer for Application in Light-Emitting Diodes
(2012-04-10)
Chu, Yu-Lin
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Cheng, Chih-Chia
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Yen, Ying-Chieh
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Chang, Feng-Chih
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應用化學系
A new supramolecular POSS electroluminescent material
(2012)
Chu, Yu-Lin
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Cheng, Chih-Chia
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Chen, Ya-Ping
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Yen, Ying-Chieh
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Chang, Feng-Chih
A new polyhedral oligomeric silsesquioxane (POSS) core star-like supramolecular blue-light electroluminescent material, 4-uracilbutyl-1-methylpyrene ether (U-PY)/octakis[dimethyl(N-(6-acetamidopyridin- 2 yl))siloxy] silsesquioxane (ODAP-POSS) has been synthesized. This U-PY/ODAP-POSS contains eight pyrene chromophore arms formed through complementary uracil-diamidopyridine (U-DAP) pairs and exhibits high quantum efficiencies and good solution processing properties. The photoluminescence spectra of U-PY/ODAP-POSS (50/50) reveal that the color is stable after heating the sample at 150 degrees C for 1 h, in contrast, the pyrene/ODAP-POSS (50/50) shows significant thermal quenching. An electroluminescence (EL) device based on U-PY/ODAP-POSS exhibits higher maximum brightness and higher luminance efficiency relative to that of the U-PY. In addition, U-PY/ODAP-POSS also behaves as an effective dopant that enhances energy transfer from itself to MEH-PPV. The U-PY/ODAP-POSS-doped MEH-PPV blends exhibit high luminance efficiency, 1.45 times greater than MEH-PPV.
A new supramolecular sulfonated polyimide for use in proton exchange membranes for fuel cells
(2010)
Ye, Yun-Sheng
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Huang, Yao-Jheng
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Cheng, Chih-Chia
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Chang, Feng-Chih
;
應用化學系
Uracil-terminated telechelic sulfonated polyimides (SPI-U) were transformed into noncovalent network membranes through biocomplementary hydrogen bonding recognition in the presence of an adenine-based crosslinking agent. SPI-U membrane exhibited dramatically improved methanol permeability, oxidative stability, proton conductivity, and selectivity relative to those of the standard SPI.
A simple approach toward low-dielectric polyimide nanocomposites: Blending the polyimide precursor with a fluorinated polyhedral oligomeric silsesquioxane
(2008-09-15)
Ye, Yun-Sheng
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Yen, Ying-Chieh
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Chen, Wen-Yi
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Cheng, Chih-Chia
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Chang, Feng-Chih
This article describes a new and simple method for preparing polyimide nanocomposites that have very low dielectric constants and good thermal properties: simply through blending the polyimide precursor with a fluorinated polyhedral oligomeric silsesquioxane derivative, octakis(dimethylsiloxyhexafluoropropyl) silsesquioxane (OF). The low polarizability of OF is compatible with polyimide matrices, such that it can improve the dispersion and free volume of the resulting composites. Together, the higher free volume and lower polarizability of OF are responsible for the lower dielectric constants of the PI-OF nanocomposites. This simple method for enhancing the properties of polyimides might have potential applicability in the electronics industry. (C) 2008 Wiley Periodicals, Inc.
Association of poly(N-isopropylacrylamide) containing nucleobase multiple hydrogen bonding of adenine for DNA recognition
(2013-04-15)
Yang, Hsiu-Wen
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Chen, Jem-Kun
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Cheng, Chih-Chia
;
Kuo, Shiao-Wei
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應用化學系
In this study we used the poly(N-isopropylacrylamide) (PNIPAAm) as a medium to generate PNIPAAm-adenine supramolecular complexes. A nucleobase-like hydrogen bonding (NLHB) between PNIPAAm and adenine was found that changed the morphology, crystalline structure, and temperature responsiveness of PNIPAAm microgels relatively to the adenine concentrations. With increasing the adenine concentration, the PNIPAAm-adenine supramolecular complexes gradually altered their morphologies from microgel particles to thin film structures and suppressed the thermodynamical coil-to-globule transition of PNIPAAm because of the NLHB existed between the PNIPAAm amide and ester groups and the adenine amide groups (C=O center dot center dot center dot H-N and N-H center dot center dot center dot N-R), verified by FTIR spectral analysis. NLHB was also diverse and extensive upon increasing the temperature; therefore, the thermoresponsive behavior of the complexes was altered with the NLBH intensity, evaluated by the inter-association equilibrium constant (K-a) above and below their LCST. Therefore, PNIPAAm can be as a medium to recognize adenine in various concentrations, which could potentially be applied in DNA recognition. (C) 2013 Elsevier B.V. All rights reserved.
Bio-complementary supramolecular polymers with effective self-healing functionality
(2015-01-01)
Cheng, Chih-Chia
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Chang, Feng-Chih
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Dai, Shenghong A.
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Lin, Yu-Li
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Lee, Duu-Jong
Complementary nucleobase-functionalized polymers, a combination of base-pair interactions and a blend of two different polymers, can be used for efficient construction of supramolecular polymer networks; these materials exhibit tunable mechanical properties, rapid thermo-responsiveness and self-healing behavior making them highly attractive for a wide range of potential applications. Herein, a multi-uracil functionalized polyhedral oligomeric silsesquioxane (POSS-U) and adenine end-capped three-arm polycaprolactone oligomer (PCL-A) have been successfully developed and show high complementary ability in both solution and the solid state owing to reversible uracil-adenine (U-A)-induced physical cross-linking. The POSS-U/PCL-A blend system demonstrates that physically crosslinked films can be readily tailored to provide the desired mechanical properties and rapidly reprocessed after damage under mild temperature conditions. Importantly, these films can also spontaneously self-heal at room temperature as an autonomously repairing material, without the need for external intervention. Thus, this new system provides a potential route toward the design and fabrication of next-generation self-healing polymers.
Biocomplementary Interaction Behavior in DNA-Like and RNA-Like Polymers
(2009-12-01)
Cheng, Chih-Chia
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Yen, Ying-Chieh
;
Ye, Yun-Sheng
;
Chang, Feng-Chih
;
應用化學系
A series of nucleobased polymers and copolymers were synthesized through atom transfer radical polymerization (ATRP). Biocomplementary DNA-and RNA-like supramolecular complexes are formed in dilute DMSO solution through nucleobase recognition. (1)H NMR titration studies of these complexes in CDCl(3) indicated that thymine-adenine (T-A) and uracil-adenine (U-A) complexes form rapidly on the NMR time scale with high association constants (up to 534 and 671 M(-1), respectively) and result in significant T(g) increase. WAXD and differential scanning calorimetry analyzes in the bulk state indicate the presence of highly physical crosslinked structures and provide further details into the nature of the self-assembly of these systems. Furthermore, this study is of discussion on the difference in the hydrogen bond strength between T-A and U-A base pairs within polymer systems, indicating that the strength of hydrogen bonds in RNA U-A pairs is stronger than that in DNA T-A base pairs. (C) 2009 Wiley Periodicals, Inc. J Polym. Sci Part A: Polym Chem 47:6388-6395, 2009
Bioinspired assembly of functional block-copolymer nanotemplates
(2013)
Lin, I. -Hong
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Cheng, Chih-Chia
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Chuang, Wei-Tsung
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Chen, Jem-Kun
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Jeng, U. -Ser
A new concept on bioinspired assembly of functional diblock copolymers, capable of forming different microstructures through nucleobase-induced supramolecular interactions, has been explored. In this paper, a new series of uracil-functionalized poly(epsilon-caprolactone)-b-(4-vinylbenzyl uracil)s (PCL-b-PVBU) have been prepared which exhibit a high self-complementary ability in solution and solid states owing to the formation of uracil-uracil pairs by induced hierarchical self-assembly. The ordered morphologies of PCL-b-PVBU diblock copolymers changed from a lamellar, hexagonally packed cylinder to a sphere with respect to the content of the hydrogen bond segment. Moreover, we further show that the PCL segment could be easily extracted by enzymatic degradation, leading to a cylinder porous structure of long-range order, which gives a facile method for the fabrication of uracil-functionalized nanotemplates. In addition, bio-complementary PCL-b-PVBU/9-hexadecyladenine (AC16) hierarchical supramolecular complexes formed through strong cooperative hydrogen bonding between the uracil group of PVBU and the adenine group of A-C16. When the mixing ratios of PCL-b-PVBU/AC16 differ from the stoichiometric ratio, these complexes self-assemble into well-ordered lamellar and hexagonal structures; the changing morphology at different AC16 loadings reveals that the molecular structures of the PCL-b-PVBU/AC16 complexes are readily tailored.
Bioinspired hole-conducting polymers for application in organic light-emitting diodes
(2012)
Cheng, Chih-Chia
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Chu, Yu-Lin
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Huang, Pei-Hsiu
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Yen, Ying-Chieh
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Chu, Chih-Wei
A novel uracil-functionalized poly(3-thiophene) as a hole-injecting/transporting layer in an organic light-emitting device is able to form physical crosslinkages resulting in high thermal stability, non-corrosion, excellent hole injection/transport and electron-blocking capabilities in the solid state, and it achieves up to 10 times higher performance than that of conventional poly(3-thiophene)s under similar experimental conditions.
Bioinspired Photo-Cross-Linked Nanofibers from Uracil-Functionalized Polymers
(2012-01-01)
Wang, Yeh-Sheng
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Cheng, Chih-Chia
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Ye, Yun-Sheng
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Yen, Ying-Chieh
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Chang, Feng-Chih
In this study, we used electrospinning to fabricate nucleobase-functionalized and photo-cross-linkable poly[1-(4-vinylbenzyl uracil)] (PVBU) nanofibers. PVBU of high-molecular-weight (M-n > 250 550 g/mol) possessed a high thermal stability and sufficient chain entanglement to produce uniform fibers without forming beads. These uracil-functionalized nanofibers were further photo-cross-linked through exposure to UV light at a wavelength of 254 nm. After immersing in N,N-dimethylacetamide, the pristine PVBU fibers dissolved, while the cross-linked PVBU fibers maintained their shape; thus, the cross-linked PVBU nanofibers exhibited good dimensional stability and improved solvent resistance.
Bioinspired supramolecular fibers for mercury ion adsorption
(2013)
Wang, Yeh-Sheng
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Cheng, Chih-Chia
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Chen, Jem-Kun
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Ko, Fu-Hsiang
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Chang, Feng-Chih
Anovel photo-cross-linkable nanofiber based on a uracil-functionalized polymer, poly[ 1-(4-vinylbenzyl uracil)] (PVBU), was prepared using the electrospinning technique. This PVBU nanofiber can be converted into a covalent network nanofiber through exposure to UV light at a wavelength of 254 nm. This PVBU nanofiber is able to distinguish and selectively remove mercury ions (Hg2+) from other metal ions in aqueous solution. The maximum Hg2+ adsorption capacity of the PVBU nanofiber is 543.9 mg g(-1), which is significantly higher than that of cyclic imide derivatives. The improved adsorption of Hg2+ allows a detection limit of less than 1 ppm, which has rarely been achieved for Hg2+ sensing. Furthermore, the PVBU fiber can be reused for 10 consecutive cycles using 1.0 M HCl treatment. This new material has significant potential for the simultaneous detection and separation of Hg2+ in environmental and industrial fields.
Block-copolymer-like supramolecules confined in nanolamellae
(2012)
Wang, Jui-Hsu
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Cheng, Chih-Chia
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Yen, Ying-Chieh
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Miao, Chia-Chun
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Chang, Feng-Chih
This paper describes the development of a new concept in supra-molecular assembly of existing functional polypeptides to form diblock-like molecular clusters through complementary hydrogen-bonding interactions, providing a potential route toward design and fabrication of block copolymer-like supramolecular materials.
Dynamic supramolecular self-assembly: hydrogen bonding-induced contraction and extension of functional polymers
(2017-06-07)
Cheng, Chih-Chia
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Wang, Jui-Hsu
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Chuang, Wei-Tsung
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Liao, Zhi-Sheng
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Huang, Jyun-Jie
Simple construction and manipulation of low-molecular-weight supramolecular polymers, based on incorporation of self-complementary multiple hydrogen bonding interactions, with the desired dynamic response characteristics to achieve high-efficiency supramolecular assembly and control the morphological properties of the polymers remain highly challenging. Herein, we developed a new difunctional tele-chelic supramolecular polymer (UrCy-PPG) containing self-complementary quadruple hydrogen-bonded ureido-cytosine (UrCy) moieties, which spontaneously self-assembles to form long-range-ordered lamellar structures in the bulk state. Scattering and rheological studies confirmed that the dynamic behavior of UrCy units induces structural phase transitions from quadruple to dual hydrogen-bonded arrays, leading to well-controlled, self-organized supramolecular nanostructure morphologies. The microstructural features could be easily tuned by altering environmental conditions, making the self-assembly processes highly efficient. Importantly, temperature/shear stress-dependent microstructural analyses indicated that UrCy-PPG has the capacity to manipulate the transition between contractile and fully extended lamellar structures. Given its novelty, simple synthesis, high reliability, and efficient self-assembly processes, this newly developed supramolecular polymer represents a new concept and pathway for controlled arrangement of self-assembled polymeric nanostructures.
Effect of LiClO4 on the thermal and morphological properties of organic/inorganic polymer hybrids
(2008-08-11)
Yen, Ying-Chieh
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Ye, Yun-Sheng
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Cheng, Chih-Chia
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Chen, Hsiu-Mei
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Sheu, Hwo-Shuenn
This paper describes the thermal properties, morphologies, and interactions within the binary and ternary blends of poly(methyl methacrylate) (PMMA), octa(phenol)octasilsesquioxane (OP-POSS), and LiClO4. In the binary PMMA/OP-POSS blends, the OP-POSS molecules tend to aggregate and result in a decrease (19 degrees C) in the glass transition temperature. In the ternary PMMA/LiClO4/OP-POSS blends, however, the OP-POSS molecules form small sphere-like domains (20 nm) leading to the composite's glass transition temperature increasing by up to 30 degrees C. Based on these FF-IR spectra, the addition of LiClO4 influenced the probability of hydrogen bonds formed between PMMA and OP-POSS and these SEM micrographs, DSC, and XRD data indicated that the addition of LiClO4 is a convenient and simple approach toward dispersing the OP-POSS nanoparticles within PMMA, where the presence of LiClO4 changes the physical effect of OP-POSS from that of a diluent role to a cross-linker role. (c) 2008 Elsevier Ltd. All rights reserved.
Efficiently controllable hybrid micelle of poly(3-adeninehexylthiophene)/[6,6]-phenyl-C61-butyric acid methyl ester for a flexible metal-insulator-semiconductor device
(2016-03-13)
Lin, Yen-Ting
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Singh, Ranjodh
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Ko, Fu-Hsiang
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Cheng, Chih-Chia
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材料科學與工程學系