Synthesis and characterization of poly(phthalazinone ether ketone ketone) copolymers with 4,4′-dihydroxybiphenyls

2020 ◽  
pp. 095400832095804
Author(s):  
Dalin Dong ◽  
Yuezhen Bin ◽  
Xigao Jian
Keyword(s):  
Intrinsic Viscosity ◽  
Molar Ratio ◽  
Elongation Ratio ◽  
Average Molecular Mass ◽  
Good Solubility ◽  
Comprehensive Properties ◽  
Molecular Masses ◽  
Ether Ketone ◽  
Average Molecular Masses

Meta-poly(phthalazinone ether ketone ketone) copolymers with 4,4′-dihydroxybiphenyls (meta-PPBEKK) was synthesized with 4,4′-dihydroxybiphenyls (BP), 1,3-bis(4-fluorobenzoyl)benzene (meta-DFKK) and 4-(4-hydroxyphenyl)-2,3-diazaphthalene-1-one (DHPZ). The copolymers are high-temperature resistant and have good solubility in many solvents. With increasing molar ratio of BP to meta-DFKK from 0 to 0.2, the addition of BP improves number-average molecular masses, intrinsic viscosity, mechanical properties and fluidity of meta-PPBEKKs. When the molar ratio of BP to meta-DFKK is 0.2, the intrinsic viscosity reaches 1.14 dL g−1, the number-average molecular mass reaches 44700 g mol−1, the maximum thermal elongation ratio reaches 14 with strength of 127.1 MPa and Young’s modulus of 2.4 GPa. With increasing molar ratio of BP to meta-DFKK from 0 to 0.2, meta-PPBEKKs have improved comprehensive properties, and make sense in many fields.

Synthesis and Characterization of Poly(Aryl Ether Quinoxaline)s with Controlled Molecular Weight

2011 ◽  
Vol 391-392 ◽  
pp. 826-829
Author(s):  
Song Ya Zhang ◽  
Zhong Xiao Li ◽  
Jia Ling Pu
Keyword(s):  
Molecular Weight ◽  
Glass Transition ◽  
Strong Acid ◽  
Decomposition Temperature ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Aryl Ether ◽  
Good Solubility ◽  
Step Procedure

Novel poly(aryl ether quinoxaline)s (PEQs) were prepared via a two-step procedure. First, poly (ether benzil) (PEB) was synthesized by the polycondensation of 4,4’-difluorobenzil and 4,4’-isopropylidenediphenol.Then, PEB was reacted with 1,2-diaminobenzene and 4,4'-oxydibenzene-1,2-diamine to give the PEQs. The molecular weight of the PEQs could be adjusted easily by varying the molar ratio of 1,2-diaminobenzene to 4,4'-oxydibenzene-1,2-diamine. The PEQs exhibited good solubility in common organic solvents such as NMP, DMAc, DMF, cyclohexanone and chloroform. In addition, the PEQs also had high glass transition (Tg) temperatures and good thermal properties, with an initial thermal decomposition temperature above 475 oC and glass transition temperatures above 210 oC. They also exhibited excellent resistance to strong acid and alkali.

scholarly journals Enzymatic synthesis and characterization of novel terpolymers from renewable sources

2019 ◽  
Vol 91 (3) ◽  
pp. 397-408
Author(s):  
Diana Aparaschivei ◽  
Anamaria Todea ◽  
August E. Frissen ◽  
Valentin Badea ◽  
Gerlinde Rusu ◽  
...  
Keyword(s):  
Polymerization Reaction ◽  
Molar Ratio ◽  
Condensation Polymerization ◽  
Average Molecular Mass ◽  
New Class ◽  
Platform Chemicals ◽  
Starting Point ◽  
Reaction Cycles ◽  
Methylene Group

Abstract 2,5-Furandicarboxylic acid and itaconic acid are both important biobased platform chemicals and their terpolymer with 1,6-hexanediol (HDO) can be the starting point for a new class of reactive polyesters, with important applications. The green synthetic route developed in this study involves a biocatalytic condensation polymerization reaction of dimethyl furan-2,5-dicarboxylate (DMFDC) and dimethyl itaconate (DMI) with HDO in toluene at 80°C, using commercial immobilized lipases from Candida antarctica B. In the best conditions, the formed polymer product was isolated with more than 80% yield, containing about 85% terpolymer with average molecular mass of about 1200 (Mn, calculated from MALDI-TOF MS data) and 15% DMFDC_HDO copolymer. Considering the higher reactivity of DMFDC, the composition of the synthesized polymer can be directed by adjusting the molar ratio of DMFDC and DMI, as well as by extending the reaction time. Structural analysis by NMR demonstrated the regioselective preference for the carbonyl group from DMI adjacent to the methylene group. The biocatalyst was successfully reused in multiple reaction cycles.

Synthesis and Characterization of Novel Fluorene-Based Poly(Imino Ketone)s

2011 ◽  
Vol 335-336 ◽  
pp. 1086-1089
Author(s):  
Lin Zhang ◽  
Guan Jun Chang ◽  
Lu Bin Miao ◽  
Run Xiong Lin
Keyword(s):  
Optical Properties ◽  
Room Temperature ◽  
Main Chain ◽  
High Glass Transition Temperature ◽  
Good Solubility ◽  
Ether Ether Ketone ◽  
Poly Ether Ether Ketone ◽  
Ft Ir ◽  
Ether Ketone

Fluorene-based poly(imino ketone)s (PIKF) were designed and synthesized by reacting 1,4-Bis-(4-bromobenzoyl)-benzene and 9,9-bis(3-R-4-aminophenyl)fluorine (R: H, CH3 or F). The structures of the resulting polymers were characterized by FT-IR, 1H NMR spectroscopy and elemental analysis. The thermo and optical properties of PIKF were evaluated. Good solubility of PIKF in ordinary organic solvents such as THF and chloroform was confirmed. PIKF were amorphous at room temperature. No phase transition except for Tg was confirmed in the DSC analysis. PIKF displayed a high glass transition temperature (Tg > 215 °C) in comparison with commercially available poly(ether ether ketone) (PEEK Tg = 169 °C). The UV-vis absorption spectrum of polymers exhibited two absorption peaks around 271 nm and 369 nm; The fluorescence spectrum of the PIKF-1, 2 and PIKF-3 showed a maximum emission wavelength at 502 nm and 491 nm, respectively. These optical properties were probably related to the cardo structure of the fluorene moiety placed on the main chain.

Characterization of Black Liquors from Soda-AQ Pulping of Reed Canary Grass (Phalaris arundinacea L.)

Holzforschung ◽  
2002 ◽  
Vol 56 (3) ◽  
pp. 298-303 ◽  
Author(s):  
Z. Feng ◽  
R. Alén ◽  
H. Pakkanen
Keyword(s):  
Chemical Composition ◽  
Wide Distribution ◽  
Phalaris Arundinacea ◽  
Reed Canary Grass ◽  
Molecular Masses ◽  
Canary Grass ◽  
Black Liquors ◽  
Average Molecular Masses ◽  
Aliphatic Carboxylic Acids

Summary Reed canary grass (Phalaris arundinacea L.) was delignified in a laboratory-scale digester by conventional soda-AQ pulping under varying conditions. The chemical composition of the corresponding black liquors was analyzed with respect to their main organic constituents. The results showed that the dry solids of the black liquors contained 33–34% lignin, 14–19% aliphatic carboxylic acids and 12–16% polysaccharides. No significant differences were found in the average molecular masses (M̄w 4700–5600 Da and M̄n 650–750 Da) of the dissolved lignins in these black liquors, although the polydispersity (M̄w /M̄n ) values (6.6–7.9) indicated that the molecular masses had a wide distribution. Lignin clearly degraded in the black liquors as delignification proceeded. Of the monosaccharide moieties detected in the polysaccharides, xylose was predominant, suggesting that xylan was a major hemicellulose constituent in the black liquors.

Synthesis and Characterization of Copolymer of Dimethyldiallylammonium Chloride and Acrylamide

2006 ◽  
Vol 11-12 ◽  
pp. 753-756 ◽  
Author(s):  
Fu Mei Wu ◽  
Xing Ying Zhang
Keyword(s):  
Petroleum Ether ◽  
Emulsion Polymerization ◽  
Intrinsic Viscosity ◽  
Ir Spectrum ◽  
Tween 80 ◽  
Redox System ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Inverse Emulsion Polymerization

The inverse emulsion polymerization of dimethyldiallylammonium chloride (DMDAAC) with acrylamide (AM) was carried out using a redox system as initiator, petroleum ether as oil, and Span-85 and Tween-80 as emulsifiers. The cationic degree of the copolymer increased markedly when AM was fed into the system in batch. The effect of DMDAAC content on the intrinsic viscosity ([η]) and solubility of the copolymer, and the methods of feeding AM on the cationic degree and solubility of the copolymer was studied in this work. The cationic degree of 39.8% of the copolymer was achieved. When the molar ratio of AM to DMDAAC was 4.0, the copolymer with [η] of 10.02 dl/g and the dissolving time less than 15min was obtained. The structure of the copolymer was also characterized by IR spectrum.

Characterization of dissolved material during the initial phase of softwood kraft pulping

TAPPI Journal ◽  
2013 ◽  
Vol 12 (1) ◽  
pp. 37-43 ◽  
Author(s):  
HANNU PAKKANEN ◽  
TEEMU PALOHEIMO ◽  
RAIMO ALÉN
Keyword(s):  
Mass Transfer ◽  
Molecular Mass ◽  
Initial Phase ◽  
Degradation Products ◽  
Kraft Pulping ◽  
Reaction Products ◽  
Cooking Temperature ◽  
Molecular Masses ◽  
Aliphatic Carboxylic Acids

The influence of various cooking parameters, such as effective alkali, cooking temperature, and cooking time on the formation of high molecular mass lignin-derived and low molecular mass carbohydrates-derived (aliphatic carboxylic acids) degradation products, mainly during the initial phase of softwood kraft pulping was studied. In addition, the mass transfer of all of these degradation products was clarified based on their concentrations in the cooking liquor inside and outside of the chips. The results indicated that the degradation of the major hemicellulose component, galactoglucomannan, typically was dependent on temperature, and the maximum degradation amount was about 60%. In addition, about 60 min at 284°F (140°C) was needed for leveling off the concentrations of the characteristic reaction products (3,4-dideoxy-pentonic and glucoisosaccharinic acids) between these cooking liquors. Compared with low molecular mass aliphatic acids, the mass transfer of soluble lignin fragments with much higher molecular masses was clearly slower.

scholarly journals Synthesis and Characterization of Partially Renewable Oleic Acid-Based Ionomers for Proton Exchange Membranes

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 130
Author(s):  
Carlos Corona-García ◽  
Alejandro Onchi ◽  
Arlette A. Santiago ◽  
Araceli Martínez ◽  
Daniella Esperanza Pacheco-Catalán ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Proton Conductivity ◽  
Electrochemical Impedance ◽  
Proton Exchange Membranes ◽  
Proton Exchange ◽  
Molar Ratio ◽  
Aromatic Diamines ◽  
Chemical Structures ◽  
Long Chain

The future availability of synthetic polymers is compromised due to the continuous depletion of fossil reserves; thus, the quest for sustainable and eco-friendly specialty polymers is of the utmost importance to ensure our lifestyle. In this regard, this study reports on the use of oleic acid as a renewable source to develop new ionomers intended for proton exchange membranes. Firstly, the cross-metathesis of oleic acid was conducted to yield a renewable and unsaturated long-chain aliphatic dicarboxylic acid, which was further subjected to polycondensation reactions with two aromatic diamines, 4,4′-(hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline and 4,4′-diamino-2,2′-stilbenedisulfonic acid, as comonomers for the synthesis of a series of partially renewable aromatic-aliphatic polyamides with an increasing degree of sulfonation (DS). The polymer chemical structures were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 19F NMR) spectroscopy, which revealed that the DS was effectively tailored by adjusting the feed molar ratio of the diamines. Next, we performed a study involving the ion exchange capacity, the water uptake, and the proton conductivity in membranes prepared from these partially renewable long-chain polyamides, along with a thorough characterization of the thermomechanical and physical properties. The highest value of the proton conductivity determined by electrochemical impedance spectroscopy (EIS) was found to be 1.55 mS cm−1 at 30 °C after activation of the polymer membrane.

scholarly journals Nanomechanical Molecular Mass Sensing Using Suspended Microchannel Resonators

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3337
Author(s):  
Alberto Martín-Pérez ◽  
Daniel Ramos ◽  
Javier Tamayo ◽  
Montserrat Calleja
Keyword(s):  
Molecular Mass ◽  
Mass Density ◽  
Applied Pressure ◽  
Atomic Mass ◽  
Liquid Sample ◽  
Mass Sensing ◽  
Average Molecular Mass ◽  
Fluid Properties ◽  
Molecular Masses ◽  
Microchannel Resonators

In this work we study the different phenomena taking place when a hydrostatic pressure is applied in the inner fluid of a suspended microchannel resonator. Additionally to pressure-induced stiffness terms, we have theoretically predicted and experimentally demonstrated that the pressure also induces mass effects which depend on both the applied pressure and the fluid properties. We have used these phenomena to characterize the frequency response of the device as a function of the fluid compressibility and molecular masses of different fluids ranging from liquids to gases. The proposed device in this work can measure the mass density of an unknown liquid sample with a resolution of 0.7 µg/mL and perform gas mixtures characterization by measuring its average molecular mass with a resolution of 0.01 atomic mass units.

scholarly journals Unravelling the Skin Secretion Peptides of the Gliding Leaf Frog, Agalychnis spurrelli (Hylidae)

Biomolecules ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 667 ◽  
Author(s):  
Carolina Proaño-Bolaños ◽  
Ailín Blasco-Zúñiga ◽  
José Rafael Almeida ◽  
Lei Wang ◽  
Miguel Angel Llumiquinga ◽  
...  
Keyword(s):  
Inhibitory Concentration ◽  
Structural Diversity ◽  
Biologically Active ◽  
Biological Characterization ◽  
Skin Secretion ◽  
Peptide Profile ◽  
Active Chemical ◽  
Molecular Masses ◽  
Skin Secretions

Frog skin secretions contain medically-valuable molecules, which are useful for the discovery of new biopharmaceuticals. The peptide profile of the skin secretion of Agalychnis spurrelli has not been investigated; therefore, the structural and biological characterization of its compounds signify an inestimable opportunity to acquire new biologically-active chemical scaffolds. In this work, skin secretion from this amphibian was analysed by molecular cloning and tandem mass spectrometry. Although the extent of this work was not exhaustive, eleven skin secretion peptides belonging to five peptide families were identified. Among these, we report the occurrence of two phyllokinins, and one medusin-SP which were previously reported in other related species. In addition, eight novel peptides were identified, including four dermaseptins, DRS-SP2 to DRS-SP5, one phylloseptin-SP1, and three orphan peptides. Phylloseptin-SP1 and dermaseptins-SP2 were identified in HPLC fractions based on their molecular masses determined by MALDI-TOF MS. Among the antimicrobial peptides, dermaseptin-SP2 was the most potent, inhibiting Escherichia coli, Staphylococcus aureus, and ORSA with a minimum inhibitory concentration (MIC) of 2.68 μM, and Candida albicans with an MIC of 10.71 μM, without haemolytic effects. The peptides described in this study represent but a superficial glance at the considerable structural diversity of bioactive peptides produced in the skin secretion of A. spurrelli.

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