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Aliphatic Dicarboxylic Acid
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Keigo Aoi – One of the best experts on this subject based on the ideXlab platform.
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Biodegradable polymers based on renewable resources. V. Synthesis and biodegradation behavior of poly(ester amide)s composed of 1,4:3,6‐dianhydro‐D‐glucitol, α‐amino Acid, and Aliphatic Dicarboxylic Acid units
Journal of Applied Polymer Science, 2001Co-Authors: Masahiko Okada, Masashi Yamada, Makito Yokoe, Keigo AoiAbstract:A series of poly(ester amide)s were synthesized by solution polycondensations of various combinations of p-toluenesulfonic Acid salts of O,O′-bis(α-aminoacyl)-1,4:3,6-dianhydro-D-glucitol and bis(p-nitrophenyl) esters of Aliphatic Dicarboxylic Acids with the methylene chain lengths of 4–10. The p-toluenesulfonic Acid salts were obtained by the reactions of 1,4:3,6-dianhydro-D-glucitol with alanine, glycine, and glycylglycine, respectively, in the presence of p-toluenesulfonic Acid. The polycondensations were carried out in N-methylpyrrolidone at 40°C in the presence of triethylamine, giving poly(ester amide)s having number-average molecular weights up to 3.8 × 104. Their structures were confirmed by FTIR, 1H-NMR, and 13C-NMR spectroscopy. Most of these poly(ester amide)s are amorphous, except those containing sebacic Acid and glycine or glycylglycine units, which are semicrystalline. All these poly(ester amide)s are soluble in a variety of polar solvents such as dimethyl sulfsulfoxide, N,N-dimethylformamide, 2,2,2-trifluoroethanol, m-cresol, pyridine, and trifluoroacetic Acid. Soil burial degradation tests, BOD measurements in an activated sludge, and enzymatic degrdegradation tests using Porcine pancreas lipase and papain indicated that these poly(ester amide)s are biodegradable, and that their biodegradability markedly depends on the molecular structure. The poly(ester amide)s were, in general, degraded more slowly than the corresponding polyesters having the same Aliphatic Dicarboxylic Acid units, both in composted soil and in an activated sludge. In the enzymatic degrdegradation, some poly(ester amide)s containing Dicarboxylic Acid components with shorter methylene chain lengths were degraded more readily than the corresponding polyesters with Porcine pancreas lipase, whereas most of the poly(ester amide)s were degraded more rapidly than the corresponding polyesters with papain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2721–2734, 2001
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biodegradable polymers based on renewable resources v synthesis and biodegradation behavior of poly ester amide s composed of 1 4 3 6 dianhydro d glucitol α amino Acid and Aliphatic Dicarboxylic Acid units
Journal of Applied Polymer Science, 2001Co-Authors: Masahiko Okada, Masashi Yamada, Makito Yokoe, Keigo AoiAbstract:A series of poly(ester amide)s were synthesized by solution polycondensations of various combinations of p-toluenesulfonic Acid salts of O,O′-bis(α-aminoacyl)-1,4:3,6-dianhydro-D-glucitol and bis(p-nitrophenyl) esters of Aliphatic Dicarboxylic Acids with the methylene chain lengths of 4–10. The p-toluenesulfonic Acid salts were obtained by the reactions of 1,4:3,6-dianhydro-D-glucitol with alanine, glycine, and glycylglycine, respectively, in the presence of p-toluenesulfonic Acid. The polycondensations were carried out in N-methylpyrrolidone at 40°C in the presence of triethylamine, giving poly(ester amide)s having number-average molecular weights up to 3.8 × 104. Their structures were confirmed by FTIR, 1H-NMR, and 13C-NMR spectroscopy. Most of these poly(ester amide)s are amorphous, except those containing sebacic Acid and glycine or glycylglycine units, which are semicrystalline. All these poly(ester amide)s are soluble in a variety of polar solvents such as dimethyl sulfsulfoxide, N,N-dimethylformamide, 2,2,2-trifluoroethanol, m-cresol, pyridine, and trifluoroacetic Acid. Soil burial degradation tests, BOD measurements in an activated sludge, and enzymatic degrdegradation tests using Porcine pancreas lipase and papain indicated that these poly(ester amide)s are biodegradable, and that their biodegradability markedly depends on the molecular structure. The poly(ester amide)s were, in general, degraded more slowly than the corresponding polyesters having the same Aliphatic Dicarboxylic Acid units, both in composted soil and in an activated sludge. In the enzymatic degrdegradation, some poly(ester amide)s containing Dicarboxylic Acid components with shorter methylene chain lengths were degraded more readily than the corresponding polyesters with Porcine pancreas lipase, whereas most of the poly(ester amide)s were degraded more rapidly than the corresponding polyesters with papain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2721–2734, 2001
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Biodegradable polymers based on renewable resources. IV. Enzymatic degradation of polyesters composed of 1,4:3.6‐dianhydro‐D‐glucitol and Aliphatic Dicarboxylic Acid moieties
Journal of Applied Polymer Science, 2000Co-Authors: Masahiko Okada, Kenji Tsunoda, Kouji Tachikawa, Keigo AoiAbstract:Enzymatic degrdegradation of a series of polyesters prepared from 1,4:3.6-dianhydro-D-glucitol (1) and Aliphatic Dicarboxylic Acids of the methylene chain length ranging from 2 to 10 were examined using seven different enzymes. Enzymatic degradability of these polyesters as estimated by water-soluble total organic carbon (TOC) measurement is dependent on the methylene chain length (m) of the Dicarboxylic Acid component for most of the enzymes examined. The most remarkable substrate specificity was observed for Rhizopus delemar lipase, which degraded polyester derived from 1 and suberic Acid (m = 6) most readily. In contrast, degradation by Porcine liver esterase was nearly independent of the structure of the polyesters. Enzymatic degradability of the polyesters based on three isomeric 1,4:3.6-dianhydrohexitols and sebacic Acid was found to decrease in the order of 1, 1,4:3.6-dianhydro-D-mannitol (2), and 1,4:3.6-dianhydro-L-iditol (3). Structural analysis of water-soluble degradation products formed during the enzymatic hydrhydrolysis of polyester 5g derived from 1 and sebacic Acid has shown that the preferential ester cleavage occurs at the O(5) position of 1,4:3.6-dianhydro-D-glucitol moiety in the polymer chain by enzymes including Porcine pancreas lipase, Rhizopus delemar lipase, and Pseudomonas sp. lipase. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 338–346, 2000
Michael R. Kessler – One of the best experts on this subject based on the ideXlab platform.
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Liquid crystalline epoxy networks with exchangeable disulfide bonds.
Soft matter, 2017Co-Authors: Yuehong Zhang, Orlando Rios, Jong K. Keum, Michael R. KesslerAbstract:A liquid crystalline epoxy network (LCEN) with exchangeable disulfide bonds is synthesized by polymerizing a biphenyl-based epoxy monomer with an Aliphatic Dicarboxylic Acid curing agent containing a disulfide bond. The effect of disulfide bonds on curing behavior and liquid crystalline (LC) phase formation of the LCEN is investigated. The presence of the disulfide bonds results in an increase in the reaction rate, leading to a reduction in liquid crystallinity of the LCEN. In order to promote LC phase formation and stabilize the self-assembled LC domains, a similar Aliphatic Dicarboxylic Acid without the disulfide bond is used as a co-curing agent to reduce the amount of exchangeable disulfide bonds in the system. After optimizing the molar ratio of the two curing agents, the resulting LCEN exhibits improved reprocessability and recyclability because of the disulfide exchange reactions, while preserving LC properties, such as the reversible LC phase transition and macroscopic LC orientation, for shape memory applications.
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Photoresponsive Liquid Crystalline Epoxy Networks with Shape Memory Behavior and Dynamic Ester Bonds
, 2016Co-Authors: Orlando Rios, Jong K. Keum, Jihua Chen, Michael R. KesslerAbstract:Functional polymers are intelligent materials that can respond to a variety of external stimuli. However, these materials have not yet found widespread real world applications because of the difficulties in fabrication and the limited number of functional building blocks that can be incorporated into a material. Here, we demonstrate a simple route to incorporate three functional building blocks (azobenzene chromophores, liquid crystals, and dynamic covalent bonds) into an epoxy-based liquid crystalline network (LCN), in which an azobenzene-based epoxy monomer is polymerized with an Aliphatic Dicarboxylic Acid to create exchangeable ester bonds that can be thermally activated. All three functional building blocks exhibited good compatibility, and the resulting materials exhibits various photomechanical, shape memory, and self-healing properties because of the azobenzene molecules, liquid crystals, and dynamic ester bonds, respectively
Masahiko Okada – One of the best experts on this subject based on the ideXlab platform.
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Biodegradable polymers based on renewable resources. V. Synthesis and biodegradation behavior of poly(ester amide)s composed of 1,4:3,6‐dianhydro‐D‐glucitol, α‐amino Acid, and Aliphatic Dicarboxylic Acid units
Journal of Applied Polymer Science, 2001Co-Authors: Masahiko Okada, Masashi Yamada, Makito Yokoe, Keigo AoiAbstract:A series of poly(ester amide)s were synthesized by solution polycondensations of various combinations of p-toluenesulfonic Acid salts of O,O′-bis(α-aminoacyl)-1,4:3,6-dianhydro-D-glucitol and bis(p-nitrophenyl) esters of Aliphatic Dicarboxylic Acids with the methylene chain lengths of 4–10. The p-toluenesulfonic Acid salts were obtained by the reactions of 1,4:3,6-dianhydro-D-glucitol with alanine, glycine, and glycylglycine, respectively, in the presence of p-toluenesulfonic Acid. The polycondensations were carried out in N-methylpyrrolidone at 40°C in the presence of triethylamine, giving poly(ester amide)s having number-average molecular weights up to 3.8 × 104. Their structures were confirmed by FTIR, 1H-NMR, and 13C-NMR spectroscopy. Most of these poly(ester amide)s are amorphous, except those containing sebacic Acid and glycine or glycylglycine units, which are semicrystalline. All these poly(ester amide)s are soluble in a variety of polar solvents such as dimethyl sulfoxide, N,N-dimethylformamide, 2,2,2-trifluoroethanol, m-cresol, pyridine, and trifluoroacetic Acid. Soil burial degradation tests, BOD measurements in an activated sludge, and enzymatic degradation tests using Porcine pancreas lipase and papain indicated that these poly(ester amide)s are biodegradable, and that their biodegradability markedly depends on the molecular structure. The poly(ester amide)s were, in general, degraded more slowly than the corresponding polyesters having the same Aliphatic Dicarboxylic Acid units, both in composted soil and in an activated sludge. In the enzymatic degradation, some poly(ester amide)s containing Dicarboxylic Acid components with shorter methylene chain lengths were degraded more readily than the corresponding polyesters with Porcine pancreas lipase, whereas most of the poly(ester amide)s were degraded more rapidly than the corresponding polyesters with papain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2721–2734, 2001
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biodegradable polymers based on renewable resources v synthesis and biodegradation behavior of poly ester amide s composed of 1 4 3 6 dianhydro d glucitol α amino Acid and Aliphatic Dicarboxylic Acid units
Journal of Applied Polymer Science, 2001Co-Authors: Masahiko Okada, Masashi Yamada, Makito Yokoe, Keigo AoiAbstract:A series of poly(ester amide)s were synthesized by solution polycondensations of various combinations of p-toluenesulfonic Acid salts of O,O′-bis(α-aminoacyl)-1,4:3,6-dianhydro-D-glucitol and bis(p-nitrophenyl) esters of Aliphatic Dicarboxylic Acids with the methylene chain lengths of 4–10. The p-toluenesulfonic Acid salts were obtained by the reactions of 1,4:3,6-dianhydro-D-glucitol with alanine, glycine, and glycylglycine, respectively, in the presence of p-toluenesulfonic Acid. The polycondensations were carried out in N-methylpyrrolidone at 40°C in the presence of triethylamine, giving poly(ester amide)s having number-average molecular weights up to 3.8 × 104. Their structures were confirmed by FTIR, 1H-NMR, and 13C-NMR spectroscopy. Most of these poly(ester amide)s are amorphous, except those containing sebacic Acid and glycine or glycylglycine units, which are semicrystalline. All these poly(ester amide)s are soluble in a variety of polar solvents such as dimethyl sulfoxide, N,N-dimethylformamide, 2,2,2-trifluoroethanol, m-cresol, pyridine, and trifluoroacetic Acid. Soil burial degradation tests, BOD measurements in an activated sludge, and enzymatic degradation tests using Porcine pancreas lipase and papain indicated that these poly(ester amide)s are biodegradable, and that their biodegradability markedly depends on the molecular structure. The poly(ester amide)s were, in general, degraded more slowly than the corresponding polyesters having the same Aliphatic Dicarboxylic Acid units, both in composted soil and in an activated sludge. In the enzymatic degradation, some poly(ester amide)s containing Dicarboxylic Acid components with shorter methylene chain lengths were degraded more readily than the corresponding polyesters with Porcine pancreas lipase, whereas most of the poly(ester amide)s were degraded more rapidly than the corresponding polyesters with papain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2721–2734, 2001
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Biodegradable polymers based on renewable resources. IV. Enzymatic degradation of polyesters composed of 1,4:3.6‐dianhydro‐D‐glucitol and Aliphatic Dicarboxylic Acid moieties
Journal of Applied Polymer Science, 2000Co-Authors: Masahiko Okada, Kenji Tsunoda, Kouji Tachikawa, Keigo AoiAbstract:Enzymatic degradation of a series of polyesters prepared from 1,4:3.6-dianhydro-D-glucitol (1) and Aliphatic Dicarboxylic Acids of the methylene chain length ranging from 2 to 10 were examined using seven different enzymes. Enzymatic degradability of these polyesters as estimated by water-soluble total organic carbon (TOC) measurement is dependent on the methylene chain length (m) of the Dicarboxylic Acid component for most of the enzymes examined. The most remarkable substrate specificity was observed for Rhizopus delemar lipase, which degraded polyester derived from 1 and suberic Acid (m = 6) most readily. In contrast, degradation by Porcine liver esterase was nearly independent of the structure of the polyesters. Enzymatic degradability of the polyesters based on three isomeric 1,4:3.6-dianhydrohexitols and sebacic Acid was found to decrease in the order of 1, 1,4:3.6-dianhydro-D-mannitol (2), and 1,4:3.6-dianhydro-L-iditol (3). Structural analysis of water-soluble degradation products formed during the enzymatic hydrolysis of polyester 5g derived from 1 and sebacic Acid has shown that the preferential ester cleavage occurs at the O(5) position of 1,4:3.6-dianhydro-D-glucitol moiety in the polymer chain by enzymes including Porcine pancreas lipase, Rhizopus delemar lipase, and Pseudomonas sp. lipase. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 338–346, 2000
Hans R. Kricheldorf – One of the best experts on this subject based on the ideXlab platform.
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Macrocycles. 19. Cyclization in the nematic phase? Polyesters derived from hydroquinone 4-hydroxybenzoate and Aliphatic Dicarboxylic Acids
Macromolecules, 2002Co-Authors: Hans R. Kricheldorf, Martin Richter, Gert SchwarzAbstract:Silylated hydroquinone 4-hydroxybenzoate (HHB) was polycondensed with Aliphatic Dicarboxylic Acid dichlorides (ADADs) in bulk at temperature up to 240 °C. These polycondensations proceeded in the nematic phase, and both transesterification and backbiting degradation were avoided as evidenced by 1 H NMR spectroscopy. The nematic LC phases were characterized by optical microscopy and DSC measurements. The MALDI-TOF mass spectra revealed the formation ofeven-membered cycles (in addition to linear oligomers), whereas odd-membered cycles were almost absent. When the reaction mixture was slightly diluted with 1-chloronaphthalene, so that the polycondensation proceeded in the isotropic phase, odd-membered cycles with a predominance of the cyclic trimer were found. When free HHB was polycondensed with ADADs in 1-chloronaphthalene at 220 °C in 1,2-dichlorobenzene at 190 °C or in the presence of pyridine at 5-10 °C, again odd-membered cycles were found. Obviously, the nematic phase enforces a parallel alignment of polyester chains with strong electronic interaction of neighboring mesogens, so that cyclization can only occur in the case of even-membered chains via hairpin conformations of the Aliphatic spacers.
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New polymer syntheses. CIX. Biodegradable, alternating copolyesters of terephthalic Acid, Aliphatic Dicarboxylic Acids, and alkane diols
Journal of Polymer Science Part A: Polymer Chemistry, 2001Co-Authors: Abbas-ali Shaik, Hans R. Kricheldorf, Martin Richter, Ralph-p. KrügerAbstract:Copolyesters with an alternating sequence of terephthalic Acid and Aliphatic Dicarboxylic Acids were prepared with three different methods. First, Dicarboxylic Acid dichlorides were reacted with bis(2-hydroxyethyl)terephthalate (BHET) in refluxing 1,2-dichlorobenzene. Second, the same monomers were polycondensed at 0–20 °C in the presence of pyridine. Third, Dicarboxylic Acid dichlorides and silylated BHET were polycondensed in bulk. Only this third method gave satisfactory molecular weights. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry revealed that the copolyesters prepared by the pyridine and silyl methods might have contained considerable fractions of cyclic oligoesters and polyesters despite the absence of transesterification and backbiting processes. The alternating sequences and thermal properties were characterized with 1H NMR specspectroscopy and differential scanning calorimetry measurements, respectively. In agreement with the alternating sequence, all copolyesters proved to be crystalline, but the crystallization was extremely slow [slower than that of poly(ethylene terephthalate)]. A second series of alternating copolyesters was prepared by the polycondensation of silylated bis(4-hydroxybut- yl)terephthalate with various Aliphatic Dicarboxylic Acid dichlorides. The resulting copolyesters showed significantly higher rates of crystallization, and the melting temperatures were higher than those of the BHET-based copolyesters. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3371–3382, 2001
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Macrocycles. 15. The Role of Cyclization in Kinetically Controlled Polycondensations. 1. Polyester Syntheses
Macromolecules, 2001Co-Authors: Hans R. Kricheldorf, Michael Rabenstein, Michael Maskos, Manfred SchmidtAbstract:Various diols were polycondensed with Dicarboxylic dichlorides in the presence of pyridine or γ-picoline. Aliphatic Dicarboxylic Acid dichlorides were reacted with 1,4-butanediol, catechol resorcin…
Alice Mija – One of the best experts on this subject based on the ideXlab platform.
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Influence of the Presence of Disulphide Bonds in Aromatic or Aliphatic Dicarboxylic Acid Hardeners Used to Produce Reprocessable Epoxidized Thermosets
Polymers, 2021Co-Authors: Chiara Di Mauro, Alice MijaAbstract:The design of polymers from renewable resources with recycling potential comes from economic and environmental problems. This work focused on the impact of disulphide bonds in the Dicarboxylic Acids reactions with three epoxidized vegetable oils (EVOs). For the first time, the comparison between aromatic vs. Aliphatic Dicarboxylic Acids, containing or not S–S bonds with EVOs was discussed and evaluated by dynamic scanning calorimetry. The obtained thermosets showed reprocessability, by the dual dynamic exchange mechanism. The virgin and reprocessed materials were characterized and the thermomechanical properties were compared. The thermosets derived from EVOs with high epoxy content combined with aromatic diAcids containing disulphide bridges showed high glass transition values (~111 °C), high crosslink densities and good solvent stability.