Special Issue "Aromatic Polymers"

A special issue of Polymers (ISSN 2073-4360).

Deadline for manuscript submissions: closed (31 October 2018)

Special Issue Editor

Guest Editor
Prof. Dr. Tatsuo Kaneko

Japan Advanced Institute of Science and Technology, Nomi, Japan
Website | E-Mail
Interests: high-performance polymers; Bio-based polymers; Liquid crystals; Gels; Biomolecules; Synthetic chemistry

Special Issue Information

Dear Colleagues,

Aromatic polymers, which wholly or partially include benzene rings and/or pseudoaromatic heterocycles, have been used in a wide field of high-performance or functional materials for a long time. This Special Issue is motivated by the observed increasing interest of various researchers in this field, including new synthetic methods of aromatic monomers and their polymerization, polymer architecture design from backbones to 2D/3D architectures, structure–property relationships, functionalization for new materials, chemistry of derivation and modification, composites with organic/inorganics, and applications as high-performance materials. In fact, topics are not limited to these works, and include all research areas concerning aromatic polymers.

Considering your prominent contributions to this interesting research topic, I would like to cordially invite you to submit an article to this Special Issue. This Special Issue will publish full research papers, communications, and review articles. I would like to bring together a collection of comprehensive reviews from leading experts and up-to-date research from notable groups in the community.

The manuscript should be submitted online before 31 October 2018. I would very much appreciate if you would consider being one of our authors.

Prof. Dr. Tatsuo Kaneko
Guest Editor

Manuscript Submission Information

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Keywords

  • New synthetic methods
  • Polymer architecture design
  • Structure-property relationships
  • Functionalization
  • Derivation and modification
  • Composites
  • Applied science

Published Papers (14 papers)

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Research

Jump to: Review

Open AccessCommunication Morphological Transformation of Peptide Nanoassemblies through Conformational Transition of Core-forming Peptides
Polymers 2019, 11(1), 39; https://doi.org/10.3390/polym11010039
Received: 31 October 2018 / Revised: 13 December 2018 / Accepted: 19 December 2018 / Published: 28 December 2018
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Abstract
Morphological control of nanostructures that are composed of amphiphilic di- or tri-block molecules by external stimuli broadens their applications for molecular containers, nanoreactors, and controlled release materials. In this study, triblock amphiphiles comprising oligo(ethylene glycol), oligo(l-lysine), and tetra(l-phenylalanine) were [...] Read more.
Morphological control of nanostructures that are composed of amphiphilic di- or tri-block molecules by external stimuli broadens their applications for molecular containers, nanoreactors, and controlled release materials. In this study, triblock amphiphiles comprising oligo(ethylene glycol), oligo(l-lysine), and tetra(l-phenylalanine) were prepared for the construction of nanostructures that can transform accompanying α-to-β transition of core-forming peptides. Circular dichroic (CD) measurements showed that the triblock amphiphiles adopted different secondary structures depending on the solvent environment: they adopt β-sheet structures in aqueous solution, while α-helix structures in 25% 2,2,2-trifluoroethanol (TFE) solution under basic pH conditions. Transmission electron microscopic (TEM) observation revealed that the triblock amphiphiles formed vesicle structures in 25% TFE aq. Solvent exchange from 25% TFE to water induced morphological transformation from vesicles to arc-shaped nanostructures accompanying α-β conformational transition. The transformable nanostructures may be useful as novel smart nanomaterials for molecular containers and micro reactors. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Preparation of PVDF/PAR Composites with Piezoelectric Properties by Post-Treatment
Polymers 2018, 10(12), 1333; https://doi.org/10.3390/polym10121333
Received: 5 November 2018 / Revised: 26 November 2018 / Accepted: 30 November 2018 / Published: 3 December 2018
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Abstract
Thermoplastic composites were prepared using poly (vinylidene fluoride) (PVDF) as the matrix with piezoelectric properties and aromatic polyarylate (PAR) as the reinforcing component. The PVDF/PAR conjugate fibers were prepared by melt conjugate spinning. The PVDF/PAR composites were prepared by compression molding of the [...] Read more.
Thermoplastic composites were prepared using poly (vinylidene fluoride) (PVDF) as the matrix with piezoelectric properties and aromatic polyarylate (PAR) as the reinforcing component. The PVDF/PAR conjugate fibers were prepared by melt conjugate spinning. The PVDF/PAR composites were prepared by compression molding of the PVDF/PAR conjugate fiber laminates at various molding temperatures. Drawing and poling post-treatments of the PVDF/PAR composites were performed to increase the β crystalline phase content of the PVDF. The morphologies of the PVDF/PAR composites were observed by scanning electron microscopy, and the tensile properties were tested using an universal testing machine. The crystal structure of the PVDF/PAR composites was confirmed by Fourier transform infrared spectroscopy and X-ray diffraction. The piezoelectric properties were tested using voltmeters and multimeters. The post-treatments enhanced the content of the β crystalline phase of the PVDF matrix, thereby improving the piezoelectric properties of the composites. A molding temperature of 180 °C, drawing temperature of 90 °C, and poling voltage of 12 kV were identified as the optimal conditions for the preparation of the PVDF/PAR composite. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Fluorinated and Bio-Based Polyamides with High Transparencies and Low Yellowness Index
Polymers 2018, 10(12), 1311; https://doi.org/10.3390/polym10121311
Received: 31 October 2018 / Revised: 22 November 2018 / Accepted: 22 November 2018 / Published: 27 November 2018
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Abstract
Bio-based polyamides with high transparency and low yellowness were synthesized using 4,4′-bis(trifluoroacetamido)-α-truxillic acid (ATA-F1) and 4,4′-bis(pentafluoropropionamido)-α-truxillic acid (ATA-F2) as a fluoroalkylated aromatic dicarboxylic acid, and various aromatic diamines. The introduction of fluorine side chains improved the transparency of the [...] Read more.
Bio-based polyamides with high transparency and low yellowness were synthesized using 4,4′-bis(trifluoroacetamido)-α-truxillic acid (ATA-F1) and 4,4′-bis(pentafluoropropionamido)-α-truxillic acid (ATA-F2) as a fluoroalkylated aromatic dicarboxylic acid, and various aromatic diamines. The introduction of fluorine side chains improved the transparency of the polyamide film, and suppressed its yellowness. On the other hand, water repellency, which should be a general characteristic of the fluorinated polymers, was not observed. By using ATA-F1 and various aromatic diamines, aromatic and fluorinated polyamides were obtained. In addition, these also demonstrated a high transparency and a low yellowness index. The heat resistance properties of all the obtained polyamides was over 250 °C, and the characteristics of the bio-based polyamides from 4-aminocinnamic acid derivatives were retained. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Creation of Superhydrophobic Poly(L-phenylalanine) Nonwovens by Electrospinning
Polymers 2018, 10(11), 1212; https://doi.org/10.3390/polym10111212
Received: 25 September 2018 / Revised: 29 October 2018 / Accepted: 30 October 2018 / Published: 31 October 2018
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Abstract
From the viewpoint of green chemistry and environmental chemistry, an important challenge in the field of superhydrophobic materials is to create them with only bio-based molecules. We developed superhydrophobic and chemically stable poly(L-phenylalanine) (PolyPhe) nonwovens by electrospinning. PolyPhe was selected because, due to [...] Read more.
From the viewpoint of green chemistry and environmental chemistry, an important challenge in the field of superhydrophobic materials is to create them with only bio-based molecules. We developed superhydrophobic and chemically stable poly(L-phenylalanine) (PolyPhe) nonwovens by electrospinning. PolyPhe was selected because, due to its very rigid chemical structure, it is one of the toughest and most hydrophobic polymers among polymers composed only of amino acids. The water contact angle on the nonwovens is a maximum of 160°, and the droplets are stably adhered and remain still on the nonwoven surface even if it is turned over, thereby suggesting a petal-type superhydrophobicity. The nonwovens show a good chemical stability, and their weight remains unchanged after 5 days immersion in acidic (pH 2) and basic (pH 12) conditions. In addition, the superhydrophobic property is not lost even after the alkali treatment. Such tough superhydrophobic materials are intriguing for further biomedical and environmental applications. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Cationic Moieties in Polystyrene Gels Swollen with d-Limonene Improved Transdermal Delivery System
Polymers 2018, 10(11), 1200; https://doi.org/10.3390/polym10111200
Received: 5 October 2018 / Revised: 19 October 2018 / Accepted: 24 October 2018 / Published: 27 October 2018
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Abstract
d-limonene, a terpene and natural compound, has been found to be an excellent penetration enhancer for transdermal drug delivery (TDD). It hence has been incorporated within various transdermal formulations. Herein, we report the application of polystyrene gel swollen with d-limonene and its [...] Read more.
d-limonene, a terpene and natural compound, has been found to be an excellent penetration enhancer for transdermal drug delivery (TDD). It hence has been incorporated within various transdermal formulations. Herein, we report the application of polystyrene gel swollen with d-limonene and its derivatives for TDD. Poly(styrene-co-divinylbenzene) (PS gel), poly(styrene-co-divinylbenzene-co-4-vinylpyridine) (PS-4VP) gel and poly(styrene-co-divinylbenzene-co-(vinylbenzyl) trimethylammonium chloride) (PS-VBAC gel) were employed as chemical gels to improve the stability of the TDD substrates. The drug permeation properties from the PS gels swollen in limonene were examined, regarding the effect of its network density as well as their rheological properties. The lowest density of the network showed the highest steady flux of the permeation at 43.7 ± 0.3 μg/cm2. FT-IR spectra were confirmed for PS-4VP and PS-VBAC, bearing cationic moieties and they could control the release of ibuprofen by the electrostatic interaction at the interface of organogel and skin. The steady state flux of skin permeation got low values from 55.2 ± 0.8 to 11.6 ± 2.0 μg/cm2, when the cationic moieties were increased. Moreover, the chemical network of PS gel swollen in limonene showed high mechanical stability illustrated by elastic modulus (G’) of about 98 kPa for 10% cross-linked PS gel. The developed PS gels swollen in limonene show highly promising results, suggesting their possible application in TDD. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle An Oligoimide Particle as a Pickering Emulsion Stabilizer
Polymers 2018, 10(10), 1071; https://doi.org/10.3390/polym10101071
Received: 14 August 2018 / Revised: 17 September 2018 / Accepted: 25 September 2018 / Published: 27 September 2018
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Abstract
A pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA)-based oligoimide (PMDA-ODA) was synthesized by a one-step procedure using water as a solvent. The PMDA-ODA particles showed excellent partial wetting properties and were stably dispersed in both water and oil phases. A stable dispersion was not [...] Read more.
A pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA)-based oligoimide (PMDA-ODA) was synthesized by a one-step procedure using water as a solvent. The PMDA-ODA particles showed excellent partial wetting properties and were stably dispersed in both water and oil phases. A stable dispersion was not obtained with comparison PMDA-ODA particles that were synthesized by a conventional two-step method using an organic solvent. Both oil-in-water and water-in-oil Pickering emulsions were prepared using the oligoimide particles synthesized in water, and the size of the emulsion droplet was controlled based on the oligoimide particle concentration. The oligoimide particles were tested to prepare Pickering emulsions using various kinds of oils. The oil-in-water Pickering emulsions were successfully applied to prepare microcapsules of the emulsion droplets. Our new Pickering emulsion stabilizer has the advantages of easy synthesis, no need for surface modification, and the capability of stabilizing both oil-in-water and water-in-oil emulsions. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Effective Reduction of Volumetric Thermal Expansion of Aromatic Polyimide Films by Incorporating Interchain Crosslinking
Polymers 2018, 10(7), 761; https://doi.org/10.3390/polym10070761
Received: 26 June 2018 / Revised: 8 July 2018 / Accepted: 9 July 2018 / Published: 11 July 2018
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Abstract
To develop a facile method for reducing the coefficient of volumetric thermal expansion (CVE) of polymer films, the thermal expansion behaviors of thermally cross-linkable polyimide (PI) films with isomeric diamine structures were investigated via thermal mechanical analyses and optical interferometry measurements. The degree [...] Read more.
To develop a facile method for reducing the coefficient of volumetric thermal expansion (CVE) of polymer films, the thermal expansion behaviors of thermally cross-linkable polyimide (PI) films with isomeric diamine structures were investigated via thermal mechanical analyses and optical interferometry measurements. The degree of crosslinking of the PI films containing the diphenylethynylene (Ph–C≡C–Ph) structure in the main chain was characterized by far-infrared (far-IR) spectra and density functional theory (DFT) calculations, and variations in the CVE induced by thermal crosslinking were quantitatively estimated. The crosslinking reactions effectively reduced the CVEs of the PI films by suppressing intermolecular free volume expansion and local molecular motions promoted at elevated temperatures. The lowest CVE value observed for a crosslinked PI cured at 400 °C (+98 ppm/K at 80–280 °C) was one of the smallest values reported to date in polymers. Incorporating interchain crosslinking into the main chain is an effective method for reducing the CVE of aromatic polymers. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Modification of PSf/SPSf Blended Porous Support for Improving the Reverse Osmosis Performance of Aromatic Polyamide Thin Film Composite Membranes
Polymers 2018, 10(6), 686; https://doi.org/10.3390/polym10060686
Received: 16 May 2018 / Revised: 8 June 2018 / Accepted: 10 June 2018 / Published: 20 June 2018
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Abstract
In this study, modification of polysulfone (PSf)/sulfonated polysulfone (SPSf) blended porous ultrafiltration (UF) support membranes was proposed to improve the reverse osmosis (RO) performance of aromatic polyamide thin film composite (TFC) membranes. The synergistic effects of solvent, polymer concentration, and SPSf doping content [...] Read more.
In this study, modification of polysulfone (PSf)/sulfonated polysulfone (SPSf) blended porous ultrafiltration (UF) support membranes was proposed to improve the reverse osmosis (RO) performance of aromatic polyamide thin film composite (TFC) membranes. The synergistic effects of solvent, polymer concentration, and SPSf doping content in the casting solution were investigated systematically on the properties of both porous supports and RO membranes. SEM and AFM were combined to characterize the physical properties of the membranes, including surface pore natures (porosity, mean pore radius), surface morphology, and section structure. A contact angle meter was used to analyze the membrane surface hydrophilicity. Permeate experiments were carried out to evaluate the separation performances of the membranes. The results showed that the PSf/SPSf blended porous support modified with 6 wt % SPSf in the presence of DMF and 14 wt % PSf had higher porosity, bigger pore diameter, and a rougher and more hydrophilic surface, which was more beneficial for fabrication of a polyamide TFC membrane with favorable reverse osmosis performance. This modified PSf/SPSf support endowed the RO membrane with a more hydrophilic surface, higher water flux (about 1.2 times), as well as a slight increase in salt rejection than the nascent PSf support. In a word, this work provides a new facile method to improve the separation performance of polyamide TFC RO membranes via the modification of conventional PSf porous support with SPSf. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle Post Self-Crosslinking of Phthalonitrile-Terminated Polyarylene Ether Nitrile Crystals
Polymers 2018, 10(6), 640; https://doi.org/10.3390/polym10060640
Received: 7 May 2018 / Revised: 28 May 2018 / Accepted: 5 June 2018 / Published: 8 June 2018
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Abstract
A novel phthalonitrile-terminated polyaryl ether nitrile (PEN-Ph) was synthesized and characterized. The crystallization behavior coexisting with the crosslinking behavior in the PEN-Ph system was confirmed by rheological measurements. DSC was applied to study the crystallization kinetics and crosslinking reaction kinetics. Through the Avrami [...] Read more.
A novel phthalonitrile-terminated polyaryl ether nitrile (PEN-Ph) was synthesized and characterized. The crystallization behavior coexisting with the crosslinking behavior in the PEN-Ph system was confirmed by rheological measurements. DSC was applied to study the crystallization kinetics and crosslinking reaction kinetics. Through the Avrami equation modified by Jeziorny, the nonisothermal crystallization kinetics were analyzed, and the Avrami exponent of about 2.2 was obtained. The analysis results of more intuitive polaring optical microscopy (POM) and SEM indicated that the shape of the crystals is similar to spherical. Moreover, the activation energy of the crystallization behavior and crosslinking behavior were obtained by the Kissinger method, and the values were about 152.7 kJ·mol−1 and 174.8 kJ·mol−1, respectively. This suggests that the activation energy of the crystallization behavior is lower than that of the crosslinking behavior, indicating that the crystallization behavior is more likely to occur than the crosslinking behavior and the crystals of PEN-Ph can be self-crosslinked to form single-polymer composites. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessArticle High Performance Soluble Polyimides from Ladder-Type Fluorinated Dianhydride with Polymorphism
Polymers 2018, 10(5), 546; https://doi.org/10.3390/polym10050546
Received: 20 April 2018 / Revised: 15 May 2018 / Accepted: 16 May 2018 / Published: 18 May 2018
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Abstract
A novel rigid semi-alicyclic dianhydride 9,10-difluoro-9,10-bis(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetracarboxylic acid dianhydride (8FDA) was reported, and its single crystal X-ray diffraction result revealed the existence of the polymorphic structure in this compound. The detail geometric configuration transition during the synthesized process was investigated, exhibiting a transition of [...] Read more.
A novel rigid semi-alicyclic dianhydride 9,10-difluoro-9,10-bis(trifluoromethyl)-9,10-dihydroanthracene-2,3,6,7-tetracarboxylic acid dianhydride (8FDA) was reported, and its single crystal X-ray diffraction result revealed the existence of the polymorphic structure in this compound. The detail geometric configuration transition during the synthesized process was investigated, exhibiting a transition of from trans- to cis- when the hydroxyl groups were substituted by fluoride with diethylaminosulfur trifluoride (DAST). Compared with the dianhydride 4,4′-(Hexaflouroisopropylidene) diphthalic anhydride (6FDA) and 1S,2R,4S,5R-cyclohexanetetracarboxylic dianhydride (HPMDA), the resulting polyimide (PI) films based on 8FDA exhibited an obviously higher glass transition temperature (Tg, 401 °C) and a much lower coefficient of thermal expansion (CTE, 14 ppm K−1). This indicates that 8FDA is an ideal building block in high-performance soluble PIs with low CTE. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessCommunication Molecular Design of Soluble Biopolyimide with High Rigidity
Polymers 2018, 10(4), 368; https://doi.org/10.3390/polym10040368
Received: 28 February 2018 / Revised: 18 March 2018 / Accepted: 24 March 2018 / Published: 26 March 2018
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Abstract
New soluble biopolyimides were prepared from a diamine derived from an exotic amino acid (4-aminocinnamic acid) with several kinds of tetracarboxylic dianhydride. The biopolyimide molecular structural flexibility was tailored by modifying the tetracarboxylic dianhydride moiety. The obtained polyimides were soluble in various solvents [...] Read more.
New soluble biopolyimides were prepared from a diamine derived from an exotic amino acid (4-aminocinnamic acid) with several kinds of tetracarboxylic dianhydride. The biopolyimide molecular structural flexibility was tailored by modifying the tetracarboxylic dianhydride moiety. The obtained polyimides were soluble in various solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, and even tetrahydrofuran. It was observed that the biopolyimide solubility was greatly dependent upon the structural flexibility (torsion energy). Flexible structure facilitated greater solubility. The synthesized biopolyimides were largely amorphous and had number-average molecular weight (Mn) in the range (5–8) × 105. The glass transition temperatures (Tg) of the polymers ranged from 259–294 °C. These polymers exhibited good thermal stability without significant weight loss up to 410 °C. The temperatures at 10% weight loss (Td10) for synthesized biopolyimide ranged from 375–397 °C. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Review

Jump to: Research

Open AccessReview Recent Advance on Polyaniline or Polypyrrole-Derived Electrocatalysts for Oxygen Reduction Reaction
Polymers 2018, 10(12), 1397; https://doi.org/10.3390/polym10121397
Received: 15 October 2018 / Revised: 4 December 2018 / Accepted: 6 December 2018 / Published: 17 December 2018
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Abstract
The fuel cell, as one of the most promising electrochemical devices, is sustainable, clean, and environmentally benign. The sluggish oxygen reduction reaction (ORR) is an important fuel cell cathodic reaction that decides the efficiency of the overall energy conversion. In order to improve [...] Read more.
The fuel cell, as one of the most promising electrochemical devices, is sustainable, clean, and environmentally benign. The sluggish oxygen reduction reaction (ORR) is an important fuel cell cathodic reaction that decides the efficiency of the overall energy conversion. In order to improve ORR efficiency, many efficient catalysts have been developed, in which the N-doped material is most popular. Polyaniline and polypyrrole as common aromatic polymers containing nitrogen were widely applied in the N-doped material. The shape-controlled N-doped carbon material can be prepared from the pyrolysis of the polyaniline or polypyrrole, which is effective to catalyze the ORR. This review is focused on the recent advance of polyaniline or polypyrrole-based ORR electrocatalysts. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessReview Design and Synthesis of Hyperbranched Aromatic Polymers for Catalysis
Polymers 2018, 10(12), 1344; https://doi.org/10.3390/polym10121344
Received: 5 November 2018 / Revised: 30 November 2018 / Accepted: 30 November 2018 / Published: 5 December 2018
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Abstract
Aromatic polymers such as poly(ether sulfone), poly(ether ketone), and polyimide have been widely used in industry due to their thermal, mechanical, and chemical stabilities. Although their application to catalysis has been limited, the introduction of a hyperbranched architecture to such aromatic polymers is [...] Read more.
Aromatic polymers such as poly(ether sulfone), poly(ether ketone), and polyimide have been widely used in industry due to their thermal, mechanical, and chemical stabilities. Although their application to catalysis has been limited, the introduction of a hyperbranched architecture to such aromatic polymers is effective in developing catalytic materials that combine the advantages of homogenous and heterogeneous catalysts. This review article overviews the recent progress on the design and synthesis of hyperbranched aromatic polymers. Several acid catalyzed reactions and the aerobic oxidation of alcohols have been demonstrated using hyperbranched aromatic polymers as catalysts. The advantage of hyperbranched polymers against linear polymers is also discussed. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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Open AccessReview Biosynthesis and Characteristics of Aromatic Polyhydroxyalkanoates
Polymers 2018, 10(11), 1267; https://doi.org/10.3390/polym10111267
Received: 17 October 2018 / Revised: 5 November 2018 / Accepted: 9 November 2018 / Published: 14 November 2018
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Abstract
Polyhydroxyalkanoates (PHAs) are polyesters synthesized by bacteria as a carbon and energy storage material. PHAs are characterized by thermoplasticity, biodegradability, and biocompatibility, and thus have attracted considerable attention for use in medical, agricultural, and marine applications. The properties of PHAs depend on the [...] Read more.
Polyhydroxyalkanoates (PHAs) are polyesters synthesized by bacteria as a carbon and energy storage material. PHAs are characterized by thermoplasticity, biodegradability, and biocompatibility, and thus have attracted considerable attention for use in medical, agricultural, and marine applications. The properties of PHAs depend on the monomer composition and many types of PHA monomers have been reported. This review focuses on biosynthesized PHAs bearing aromatic groups as side chains. Aromatic PHAs show characteristics different from those of aliphatic PHAs. This review summarizes the types of aromatic PHAs and their characteristics, including their thermal and mechanical properties and degradation behavior. Furthermore, the effect of the introduction of an aromatic monomer on the glass transition temperature (Tg) of PHAs is discussed. The introduction of aromatic monomers into PHA chains is a promising method for improving the properties of PHAs, as the characteristics of aromatic PHAs differ from those of aliphatic PHAs. Full article
(This article belongs to the Special Issue Aromatic Polymers)
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