“…Zhang et al [120] tested a polymer specifically for AC applications with strong fields. EO polymers can exhibit very high EO coefficients of up to 300 pm V −1 [136][137][138] while the refraction index is in the order of magnitude of 2. Another example is discussed in [139], where an integrated waveguide Mach-Zehnder interferometer exploits an EO-polymer placed on a coupled micro-ring resonator.…”
Due to the necessary transition to renewable energy, the transport of electricity over long distances will become increasingly important, since the sites of sustainable electricity generation, such as wind or solar power parks, and the place of consumption can be very far apart. Currently, electricity is mainly transported via overhead AC lines. However, studies have shown that for long distances, transport via DC offers decisive advantages. To make optimal use of the existing route infrastructure, simultaneous AC and DC, or hybrid transmission, should be employed. The resulting electric field strengths must not exceed legally prescribed thresholds to avoid potentially harmful effects on humans and the environment. However, accurate quantification of the resulting electric fields is a major challenge in this context, as they can be easily distorted (e.g., by the measurement equipment itself). Nonetheless knowledge of the undisturbed field strengths from DC up to several multiples of the fundamental frequency of the power-grid (up to 1\,kHz) is required to ensure compliance with the thresholds. 
Both AC and DC electric fields can result in the generation of corona ions in the vicinity of the line. In the case of pure AC fields, the corona ions generated typically recombine in the immediate vicinity of the line and, therefore, have no influence on the field measurement further away. Unfortunately, this assumption does not hold for DC fields and hybrid fields, where corona ions can be transported far away from the line (e.g., by wind), and potentially interact with the measurement equipment yielding incorrect measurement results. This review will provide a comprehensive overview of the current state-of-the-art technologies and methods which have been developed to address the problems of measuring the electric field near hybrid power lines.
“…Zhang et al [120] tested a polymer specifically for AC applications with strong fields. EO polymers can exhibit very high EO coefficients of up to 300 pm V −1 [136][137][138] while the refraction index is in the order of magnitude of 2. Another example is discussed in [139], where an integrated waveguide Mach-Zehnder interferometer exploits an EO-polymer placed on a coupled micro-ring resonator.…”
Due to the necessary transition to renewable energy, the transport of electricity over long distances will become increasingly important, since the sites of sustainable electricity generation, such as wind or solar power parks, and the place of consumption can be very far apart. Currently, electricity is mainly transported via overhead AC lines. However, studies have shown that for long distances, transport via DC offers decisive advantages. To make optimal use of the existing route infrastructure, simultaneous AC and DC, or hybrid transmission, should be employed. The resulting electric field strengths must not exceed legally prescribed thresholds to avoid potentially harmful effects on humans and the environment. However, accurate quantification of the resulting electric fields is a major challenge in this context, as they can be easily distorted (e.g., by the measurement equipment itself). Nonetheless knowledge of the undisturbed field strengths from DC up to several multiples of the fundamental frequency of the power-grid (up to 1\,kHz) is required to ensure compliance with the thresholds. 
Both AC and DC electric fields can result in the generation of corona ions in the vicinity of the line. In the case of pure AC fields, the corona ions generated typically recombine in the immediate vicinity of the line and, therefore, have no influence on the field measurement further away. Unfortunately, this assumption does not hold for DC fields and hybrid fields, where corona ions can be transported far away from the line (e.g., by wind), and potentially interact with the measurement equipment yielding incorrect measurement results. This review will provide a comprehensive overview of the current state-of-the-art technologies and methods which have been developed to address the problems of measuring the electric field near hybrid power lines.
“…The detailed steps of the reaction are presented in Scheme S1. The polymerization conditions employed in this study have been utilized in the preparation of numerous previously reported perfluorinated organic polymers [1,3,10,23]. As stated in the literature, the preparation of polymers containing HFB or DFB linkers was conducted under mild conditions, with relatively low temperatures not exceeding 80 • C, along with a prolonged stirring time [25].…”
Section: Nucleophilic Aromatic Substitution (Nas) and The Cross-linki...mentioning
confidence: 99%
“…PFPs possess tunable properties such as thermal and oxidative stability, hydrophobicity, lipophobicity, dielectric properties, and adjustable polarity. This enables their utilization in a diverse array of fields [9,10].…”
This study reports on the synthesis and characterization of novel perfluorinated organic polymers with azo- and azomethine-based linkers using nucleophilic aromatic substitution. The polymers were synthesized via the incorporation of decafluorobiphenyl and hexafluorobenzene linkers with diphenols in the basic medium. The variation in the linkers allowed the synthesis of polymers with different fluorine and nitrogen contents. The rich fluorine polymers were slightly soluble in THF and have shown molecular weights ranging from 4886 to 11,948 g/mol. All polymers exhibit thermal stability in the range of 350–500 °C, which can be attributed to their structural geometry, elemental contents, branching, and cross-linking. For instance, the cross-linked polymers with high nitrogen content, DAB-Z-1h and DAB-Z-1O, are more stable than azomethine-based polymers. The cross-linking was characterized by porosity measurements. The azo-based polymer exhibited the highest surface area of 770 m2/g with a pore volume of 0.35 cm3/g, while the open-chain azomethine-based polymer revealed the lowest surface area of 285 m2/g with a pore volume of 0.0872 cm3/g. Porous structures with varied hydrophobicities were investigated as adsorbents for separating water-benzene and water-phenol mixtures and selectively binding methane/carbon dioxide gases from the air. The most hydrophobic polymers containing the decafluorbiphenyl linker were suitable for benzene separation, while the best methane uptake values were 6.14 and 3.46 mg/g for DAB-Z-1O and DAB-A-1O, respectively. On the other hand, DAB-Z-1h, with the highest surface area and being rich in nitrogen sites, has recorded the highest CO2 uptake at 298 K (17.25 mg/g).
“…Further steps of the reaction mechanism are enclosed in Scheme S1. This polymerization methodology has been applied to prepare several reported per uorinated organic polymers [1,4,10,21]. According to literature, the polymers that contain HFB or DFB linkers were prepared under mild conditions of relatively low temperatures that did not exceed 80 °C with long stirring time [22].…”
Section: Nucleophilic Aromatic Substitution (Nas) and Cross-linking F...mentioning
confidence: 99%
“…Their synthesis has also been exploited in the polymer industry, thus enhancing the formation of new materials that possess high-temperature stability, high glass transition temperature, an anti-ammable nature, resistance to solvents, and are applicable for gas separation [7,8]. In addition, the tunable properties of FOPs include: their thermal and oxidative stability, hydrophobicity, lipophobicity, dielectric properties, and tunable polarity, allowing their usage in a wide range of applications [9,10].…”
A new series of ether-linked, per-fluorinated organic polymers bearing azo- (-N = N-) and azomethane (-C = N-) organic linkers was reported. The synthetic methodology relied on applying the nucleophilic aromatic substitution reaction (NAS) to fluorinated linkers (e.g. decafluorobiphenyl and hexaflourobenzene) and diols of azo- and azomethane linkers. The successful formation of the new structures revealing ether-linkage substitution of selected fluorine sites was confirmed by 1H-, 13C-, 19F-NMR and FTIR. All polymers were thermally stable in the range of 350–500 °C due to the variation of fluorine and nitrogen contents. The extended conjugation of the polymers was confirmed by the changes in the UV-Vis spectra of the organic linkers and their corresponding polymers. A notable hypsochromic shift was observed in all cases, which was more pronounced with azo-based fluorinated chains due to the H-bonding on the nitrogen sites, chain conformations and planarity. The optical band gap (Eg) of the polymers was determined from the UV-Vis. The Eg values of azo-based fluorinated polymers were higher by 1eV compared to their corresponding linkers. The 19F-NMR analysis confirmed two types of NAS on both the ortho- and para- positions of the fluorinated linkers. These connections created the possibility of developing cross-linked frameworks beside the open-chain confirmation with tailored hydrophobic nature. The cross-linking formation was characterized by porosity measurements, including surface area (SA), pore size and pore volume. The highest measured values were recorded for the azo-based polymer (DAB-Z-1h), which reached 438 m2/g and a pore volume of 0.35 cm3/g. A surface area of 105 m2/g was the lowest for the open-chain azomethane-based polymer (DAB-A-1O) with a pore volume of 0.0872 cm3/g. The beneficial formation of porous structures with varied hydrophobic nature was investigated as adsorbents for separating water/benzene, water/phenol and the selective binding of methane/carbon dioxide gases from the air. The most hydrophobic polymers that contain the decafluorbiphenyl linker were suitable for benzene separation, and the superior methane uptake values were 6.14 and 3.46 mg/g, for DAB-Z-1O and DAB-A-1O, respectively. On the other hand, DAB-Z-1h, with the highest surface area (438 m2/g) and rich with nitrogen sites, has the highest CO2 uptake at 298 K (17.25 mg/g).
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