A Novel Photosensitive Polyimide: A Polyimide Containing the Hydroxytriphenylamine Structure with Diazonaphthoquinone

2000 ◽  
Vol 12 (1) ◽  
pp. 177-184 ◽  
Author(s):  
Satoshi Akimoto ◽  
Mitsutoshi Jikei ◽  
Masa-aki Kakimoto
Keyword(s):  
Aqueous Solution ◽  
Phthalic Anhydride ◽  
Ring Opening ◽  
Polyimide Film ◽  
Tetramethylammonium Hydroxide ◽  
Thermal Cyclization

A novel photosensitive polyimide based on a polyimide containing the hydroxytriphenylamine structure (HTA-PI) and 2, 3, 4-tris[1-oxo-2-diazonaphthoquinone-4-sulfonyloxy] benzophenone (D4SB) as a photoreactive compound has been developed. The HTAPI was prepared by the ring-opening polyaddition of 4, 4′-hexafluoroisopropylidenebis(phthalic anhydride) (6FDA) and 4,4′-diamino-4″-hydroxytriphenylamine (DHTA), followed by thermal cyclization in refluxing N-methyl-2-pyrrolidone (NMP). The resulting polyimide film showed excellent transparency to 436 nm light. Photosensitive polyimide containing 30 wt% of D4SB showed a sensitivity of 800 mJ cm−2 and a contrast of 0.8 when it was exposed to 436 nm light followed by development with 5% tetramethylammonium hydroxide (TMAH) aqueous solution at 45°C.

scholarly journals Ring-Opening Copolymerization of Cyclohexene Oxide and Cyclic Anhydrides Catalyzed by Bimetallic Scorpionate Zinc Catalysts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1651
Author(s):  
Felipe de la Cruz-Martínez ◽  
Marc Martínez de Sarasa Buchaca ◽  
Almudena del Campo-Balguerías ◽  
Juan Fernández-Baeza ◽  
Luis F. Sánchez-Barba ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reaction Mechanism ◽  
Catalytic System ◽  
Phthalic Anhydride ◽  
Ring Opening ◽  
High Selectivity ◽  
Zinc Complexes ◽  
Cyclohexene Oxide ◽  
Reaction Conditions ◽  
Cyclic Anhydrides

The catalytic activity and high selectivity reported by bimetallic heteroscorpionate acetate zinc complexes in ring-opening copolymerization (ROCOP) reactions involving CO2 as substrate encouraged us to expand their use as catalysts for ROCOP of cyclohexene oxide (CHO) and cyclic anhydrides. Among the catalysts tested for the ROCOP of CHO and phthalic anhydride at different reaction conditions, the most active catalytic system was the combination of complex 3 with bis(triphenylphosphine)iminium as cocatalyst in toluene at 80 °C. Once the optimal catalytic system was determined, the scope in terms of other cyclic anhydrides was broadened. The catalytic system was capable of copolymerizing selectively and efficiently CHO with phthalic, maleic, succinic and naphthalic anhydrides to afford the corresponding polyester materials. The polyesters obtained were characterized by spectroscopic, spectrometric, and calorimetric techniques. Finally, the reaction mechanism of the catalytic system was proposed based on stoichiometric reactions.

scholarly journals Solution structures of nisin A and its two major degradation products determined by n.m.r

1992 ◽  
Vol 283 (2) ◽  
pp. 413-420 ◽  
Author(s):  
L Y Lian ◽  
W C Chan ◽  
S D Morley ◽  
G C Roberts ◽  
B W Bycroft ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ring Opening ◽  
Polypeptide Chain ◽  
Degradation Products ◽  
Correlation Spectroscopy ◽  
Solution Structures ◽  
Stimulated Annealing ◽  
Nuclear Overhauser Enhancement ◽  
Stereospecific Assignments ◽  
Nuclear Overhauser

The conformations of nisin and two major degradation products, nisin-(1-32)-peptide (nisin1-32) and des-delta Ala5-nisin1-32 (where delta Ala is alpha beta-didehydroalanine), in aqueous solution have been determined from n.m.r. data. Sequential assignments of the peptides using correlation spectroscopy (‘COSY‘), homonuclear Hartmann-Hahn spectroscopy (‘HOHAHA’), nuclear Overhauser enhancement spectroscopy (NOESY), relayed NOESY and rotating-frame nuclear Overhauser spectroscopy (ROESY) experiments are presented, including stereospecific assignments of beta-methylene protons of the lanthionine residues. ROESY experiments are also used to detect flexible regions in the polypeptide chain. A dynamic-stimulated-annealing approach is used for structural determination. It can be concluded that all these peptides are flexible in aqueous solution, with no experimental evidence of preferred overall conformations; the only defined conformational features are imposed by the presence of the lanthionine residues. Low-temperature studies also reveal that des-delta Ala5-nisin1-32 adopts conformations similar to those when the ring is intact, suggesting that the loss of activity of this degradation product is due to the absence of the delta Ala5 residue rather than to the conformational consequences of ring-opening.

Synthesis and Characterization of Alkyd Resin Based on Soybean Oil Polyols

2011 ◽  
Vol 239-242 ◽  
pp. 1721-1724 ◽  
Author(s):  
Xiao Qing Zheng ◽  
Li Ting Yang ◽  
Kun Peng Wang
Keyword(s):  
Maleic Anhydride ◽  
Soybean Oil ◽  
Phthalic Anhydride ◽  
Alkyd Resin ◽  
Ring Opening ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Hydroxyl Value

Soybean oil-based alkyd resin was prepared using soy-based polyol, maleic anhydride and phthalic anhydride. The soy-based polyol was obtained through the epoxidization of soybean oil, followed by ring-opening with methanol and, the hydroxyl values of soybean oil-based polyols used in this reaction is 169.93 mgKOH/g. In the reactions of soy-based polyol, maleic anhydride and phthalic anhydride, the molar ratio of hydroxyl value is equal to carboxyl value and the molar ratio of maleic anhydride to phthalic anhydride is 2:1, 1:1 and 1:2, respectively. 1% hydroquinone based on total reactants was used as inhibitor of polymerization, 1% dibutyltin oxide was used as catalyst.

Acid-Catalyzed Ring Opening of Furan in Aqueous Solution

2017 ◽  
Vol 32 (4) ◽  
pp. 4139-4148 ◽  
Author(s):  
Xiao Liang ◽  
Brian S. Haynes ◽  
Alejandro Montoya
Keyword(s):  
Aqueous Solution ◽  
Ring Opening ◽  
Acid Catalyzed

The dependence of AlN molar fraction of AlGaN in wet etching by using tetramethylammonium hydroxide aqueous solution

2019 ◽  
Vol 58 (SC) ◽  
pp. SCCC30 ◽  
Author(s):  
Shinji Yasue ◽  
Kosuke Sato ◽  
Yuta Kawase ◽  
Junya Ikeda ◽  
Yusuke Sakuragi ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Molar Fraction ◽  
Wet Etching ◽  
Tetramethylammonium Hydroxide

1,8-Naphthyridine Modified Rhodamine B Derivatives: Turn-On Colorimetric Sensor for Cu2+

2014 ◽  
Vol 881-883 ◽  
pp. 1079-1082 ◽  
Author(s):  
Gao Zhang Gou ◽  
He Ping Yan ◽  
Shi Juan Xu ◽  
Na Wu ◽  
Bo Zhou ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Complex Formation ◽  
Metal Complex ◽  
Rhodamine B ◽  
Ring Opening ◽  
High Selectivity ◽  
Colour Change ◽  
Detection Mechanism ◽  
Biologically Relevant ◽  
Turn On

A 1,8-naphthyridine modified rhodamine B derivative, one Cu2+-selective chemosensors was designed, synthesized and characterized, which display a high selectivity for Cu2+among environmentally and biologically relevant metal ions. It can detect Cu2+in aqueous solution selectively with a dramatic colour change from colorless to magenta. The detection mechanism involves a ring-opening process as a consequence of metal complex formation. Jobs plots study indicated that the chemosensor chelated Cu2+with 2:1 stoichiometry.

Relationship between surface free energy and development process (swelling and dissolution kinetics) of poly(4-hydroxystyrene) film in water and 2.38 wt% tetramethylammonium hydroxide aqueous solution

2021 ◽  
Author(s):  
Yuko Tsutsui Ito ◽  
Takahiro KOZAWA
Keyword(s):  
Aqueous Solution ◽  
Free Energy ◽  
Surface Free Energy ◽  
Water Intake ◽  
Dissolution Kinetics ◽  
Exposure Dose ◽  
Tetramethylammonium Hydroxide ◽  
Polar Components ◽  
Dispersion Component ◽  
Chemically Amplified Resists

Abstract With the sharpening of optical images, the capability of resist materials has become a serious concern in lithography. The dissolution of a resist polymer is key to the realization of ultrafine patterning. However, the details of the dissolution of resist polymers remain unclarified. In this study, the relationships of surface free energy with swelling and dissolution kinetics were investigated using poly(4-hydroxystyrene) (PHS) film with triphenylsulfonium-nonaflate (TPS-nf). Developers were water and 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution. PHS and TPS-nf are a typical backbone polymer (a dissolution agent) and a typical acid generator of chemically amplified resists, respectively. The water intake and dissolution of PHS film with TPS-nf became fast with increasing UV exposure dose. It was found that the increase in the polar components (particularly, the hydrogen bonding component) and the decrease in the dispersion component of surface free energy underlie the fast water intake and dissolution.

Sign in / Sign up

Export Citation Format

Share Document