Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline
Objectives. Our aim was to study the dielectric properties of the 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4’-methylaniline system and reveal how different concentrations of N-(4-n-butyloxybenzylidene)-4’-methylaniline additives affect the dielectric properties of 4-n-pentyloxybenzoic...
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MIREA - Russian Technological University
2021-05-01
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| Series: | Тонкие химические технологии |
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| Online Access: | https://www.finechem-mirea.ru/jour/article/view/1697 |
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| author | S. A. Syrbu M. S. Fedorov E. A. Lapykina V. V. Novikov |
| author_facet | S. A. Syrbu M. S. Fedorov E. A. Lapykina V. V. Novikov |
| author_sort | S. A. Syrbu |
| collection | DOAJ |
| description | Objectives. Our aim was to study the dielectric properties of the 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4’-methylaniline system and reveal how different concentrations of N-(4-n-butyloxybenzylidene)-4’-methylaniline additives affect the dielectric properties of 4-n-pentyloxybenzoic acid.Methods. System properties were investigated using polarization thermomicroscopy and dielcometry.Results. We found that dielectric anisotropy changes its sign from positive to negative at the transition temperature of the high-temperature nematic subphase to the low-temperature one. The anisotropy of the dielectric constant of N-4-n-butoxybenzylidene-4’-methylaniline has a positive value and increases as to the system approaches the crystalline phase. The crystal structure of the 4-n-pentyloxybenzoic acid contains dimers formed by two independent molecules due to a pair of hydrogen bonds. The crystal structure of N-(4-n-butoxybenzylidene)-4’-methylaniline contains associates formed by orientational interactions of two independent molecules. 4-n-Pentyloxybenzoic acid dimers (270 nm) and associates of N-4-n-butoxybenzylidene-4’- methylaniline (250 nm) proved to have approximately the identical length. Considering the close length values of the structural units of both compounds and the dielectric anisotropy sign, we assume that the N-4-n-butoxybenzylidene-4’-methylaniline associates are incorporated into the supramolecular structure of the 4-n-pentyloxybenzoic acid. The specific electrical conductivity of the compounds under study lies between 10−7 and 10−12 S∙cm−1. The relationship between the specific electrical conductivity anisotropy and the system composition in the nematic phase at the identical reduced temperature, obtained between 100 and 1000 Hz is symbatic. However, the electrical conductivity anisotropy values of the system obtained at 1000 Hz are lower compared to those obtained at 100 Hz. At N-(4-n-butoxybenzylidene)-4’-methylaniline concentrations between 30 and 60 mol %, the electrical conductivity anisotropy values are higher than those of the individual component.Conclusions. A change in the sign of the dielectric constant anisotropy of the 4-n-pentyloxybenzoic acid during nematic subphase transitions was established. We showed that the system has the highest dielectric constant anisotropy value when components have an equal number of moles. Highest electrical conductivity anisotropy values are observed when the concentration of the N-4-n-butoxybenzylidene-4᾽-methylaniline system lies between 30 and 60 mol %. |
| format | Article |
| id | doaj-art-48d86d6c08824c54bdbdcae0617b4d44 |
| institution | Kabale University |
| issn | 2410-6593 2686-7575 |
| language | Russian |
| publishDate | 2021-05-01 |
| publisher | MIREA - Russian Technological University |
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| series | Тонкие химические технологии |
| spelling | doaj-art-48d86d6c08824c54bdbdcae0617b4d442025-08-20T03:42:45ZrusMIREA - Russian Technological UniversityТонкие химические технологии2410-65932686-75752021-05-0116213814710.32362/2410-6593-2021-16-2-138-1471630Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylanilineS. A. Syrbu0M. S. Fedorov1E. A. Lapykina2V. V. Novikov3Ivanovo Fire and Rescue Academy of State Firefighting Service of Ministry of Russian Federation for Civil Defense, Emergencies and Elimination of Consequences of Natural DisastersIvanovo State UniversityIvanovo State UniversityIvanovo State UniversityObjectives. Our aim was to study the dielectric properties of the 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4’-methylaniline system and reveal how different concentrations of N-(4-n-butyloxybenzylidene)-4’-methylaniline additives affect the dielectric properties of 4-n-pentyloxybenzoic acid.Methods. System properties were investigated using polarization thermomicroscopy and dielcometry.Results. We found that dielectric anisotropy changes its sign from positive to negative at the transition temperature of the high-temperature nematic subphase to the low-temperature one. The anisotropy of the dielectric constant of N-4-n-butoxybenzylidene-4’-methylaniline has a positive value and increases as to the system approaches the crystalline phase. The crystal structure of the 4-n-pentyloxybenzoic acid contains dimers formed by two independent molecules due to a pair of hydrogen bonds. The crystal structure of N-(4-n-butoxybenzylidene)-4’-methylaniline contains associates formed by orientational interactions of two independent molecules. 4-n-Pentyloxybenzoic acid dimers (270 nm) and associates of N-4-n-butoxybenzylidene-4’- methylaniline (250 nm) proved to have approximately the identical length. Considering the close length values of the structural units of both compounds and the dielectric anisotropy sign, we assume that the N-4-n-butoxybenzylidene-4’-methylaniline associates are incorporated into the supramolecular structure of the 4-n-pentyloxybenzoic acid. The specific electrical conductivity of the compounds under study lies between 10−7 and 10−12 S∙cm−1. The relationship between the specific electrical conductivity anisotropy and the system composition in the nematic phase at the identical reduced temperature, obtained between 100 and 1000 Hz is symbatic. However, the electrical conductivity anisotropy values of the system obtained at 1000 Hz are lower compared to those obtained at 100 Hz. At N-(4-n-butoxybenzylidene)-4’-methylaniline concentrations between 30 and 60 mol %, the electrical conductivity anisotropy values are higher than those of the individual component.Conclusions. A change in the sign of the dielectric constant anisotropy of the 4-n-pentyloxybenzoic acid during nematic subphase transitions was established. We showed that the system has the highest dielectric constant anisotropy value when components have an equal number of moles. Highest electrical conductivity anisotropy values are observed when the concentration of the N-4-n-butoxybenzylidene-4᾽-methylaniline system lies between 30 and 60 mol %.https://www.finechem-mirea.ru/jour/article/view/1697liquid crystalsmixtures of nematogensdielcometryanisotropy of dielectric constantanisotropy of electrical conductivity |
| spellingShingle | S. A. Syrbu M. S. Fedorov E. A. Lapykina V. V. Novikov Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline Тонкие химические технологии liquid crystals mixtures of nematogens dielcometry anisotropy of dielectric constant anisotropy of electrical conductivity |
| title | Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline |
| title_full | Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline |
| title_fullStr | Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline |
| title_full_unstemmed | Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline |
| title_short | Dielectric properties of the system: 4-n-pentyloxybenzoic acid– N-(4-n-butyloxybenzylidene)-4᾽-methylaniline |
| title_sort | dielectric properties of the system 4 n pentyloxybenzoic acid n 4 n butyloxybenzylidene 4᾽ methylaniline |
| topic | liquid crystals mixtures of nematogens dielcometry anisotropy of dielectric constant anisotropy of electrical conductivity |
| url | https://www.finechem-mirea.ru/jour/article/view/1697 |
| work_keys_str_mv | AT sasyrbu dielectricpropertiesofthesystem4npentyloxybenzoicacidn4nbutyloxybenzylidene4methylaniline AT msfedorov dielectricpropertiesofthesystem4npentyloxybenzoicacidn4nbutyloxybenzylidene4methylaniline AT ealapykina dielectricpropertiesofthesystem4npentyloxybenzoicacidn4nbutyloxybenzylidene4methylaniline AT vvnovikov dielectricpropertiesofthesystem4npentyloxybenzoicacidn4nbutyloxybenzylidene4methylaniline |