{"title":"分子链的柔韧性和高频介电损耗:聚酯酰亚胺中酯键排列的影响","authors":"Ya-Dong Li, Hong Li, Lu-Kun Feng, Feng Bao, Ming-Liang Wang, Cai-Zhen Zhu, Zhao-Hui Zheng, Xiao-Bin Ding, Jian Xu","doi":"10.1007/s10118-024-3140-6","DOIUrl":null,"url":null,"abstract":"<div><p>The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer media. Traditionally, it has been theorized that rigid molecular chains lead to lower dielectric loss. However, the validity of this proposition at high frequencies remains uncertain. To scrutinize the correlation between chain flexibility and dielectric properties, we synthesized six poly(ester imide)s (PEIs) with systematically varied molecular chain flexibilities by modifying the ester’s substitution on the aromatic ring. The introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor (<i>D</i><sub>f</sub>), ranging from 0.0021 to 0.0038 at 10 GHz in dry conditions. The dry <i>D</i><sub>f</sub> displayed a pattern consistent with volume polarizability (<i>P/V</i>). Unexpectedly, PI-mmm-T, featuring the most flexible molecular chain, exhibited the lowest dielectric loss under both dry (0.0021 @ 10 GHz) and hygroscopic (0.0029 @ 10 GHz) conditions. Furthermore, the observed increase in <i>D</i><sub>f</sub> after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic nature. Molecular simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains, after close stacking, impede the entry of water molecules. Despite sacrificing high-temperature resistance, the precursor exhibited enhanced solubility properties and could be processed into high-quality films. Our research unveils new insights into the relationship between flexibility and high-frequency dielectric loss, offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.</p></div>","PeriodicalId":517,"journal":{"name":"Chinese Journal of Polymer Science","volume":"42 8","pages":"1122 - 1133"},"PeriodicalIF":4.1000,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Molecular Chain Flexibility and Dielectric Loss at High-Frequency: Impact of Ester Bond Arrangement in Poly(ester imide)s\",\"authors\":\"Ya-Dong Li, Hong Li, Lu-Kun Feng, Feng Bao, Ming-Liang Wang, Cai-Zhen Zhu, Zhao-Hui Zheng, Xiao-Bin Ding, Jian Xu\",\"doi\":\"10.1007/s10118-024-3140-6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer media. Traditionally, it has been theorized that rigid molecular chains lead to lower dielectric loss. However, the validity of this proposition at high frequencies remains uncertain. To scrutinize the correlation between chain flexibility and dielectric properties, we synthesized six poly(ester imide)s (PEIs) with systematically varied molecular chain flexibilities by modifying the ester’s substitution on the aromatic ring. The introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor (<i>D</i><sub>f</sub>), ranging from 0.0021 to 0.0038 at 10 GHz in dry conditions. The dry <i>D</i><sub>f</sub> displayed a pattern consistent with volume polarizability (<i>P/V</i>). Unexpectedly, PI-mmm-T, featuring the most flexible molecular chain, exhibited the lowest dielectric loss under both dry (0.0021 @ 10 GHz) and hygroscopic (0.0029 @ 10 GHz) conditions. Furthermore, the observed increase in <i>D</i><sub>f</sub> after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic nature. Molecular simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains, after close stacking, impede the entry of water molecules. Despite sacrificing high-temperature resistance, the precursor exhibited enhanced solubility properties and could be processed into high-quality films. Our research unveils new insights into the relationship between flexibility and high-frequency dielectric loss, offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.</p></div>\",\"PeriodicalId\":517,\"journal\":{\"name\":\"Chinese Journal of Polymer Science\",\"volume\":\"42 8\",\"pages\":\"1122 - 1133\"},\"PeriodicalIF\":4.1000,\"publicationDate\":\"2024-06-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chinese Journal of Polymer Science\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10118-024-3140-6\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"POLYMER SCIENCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chinese Journal of Polymer Science","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s10118-024-3140-6","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
Molecular Chain Flexibility and Dielectric Loss at High-Frequency: Impact of Ester Bond Arrangement in Poly(ester imide)s
The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer media. Traditionally, it has been theorized that rigid molecular chains lead to lower dielectric loss. However, the validity of this proposition at high frequencies remains uncertain. To scrutinize the correlation between chain flexibility and dielectric properties, we synthesized six poly(ester imide)s (PEIs) with systematically varied molecular chain flexibilities by modifying the ester’s substitution on the aromatic ring. The introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor (Df), ranging from 0.0021 to 0.0038 at 10 GHz in dry conditions. The dry Df displayed a pattern consistent with volume polarizability (P/V). Unexpectedly, PI-mmm-T, featuring the most flexible molecular chain, exhibited the lowest dielectric loss under both dry (0.0021 @ 10 GHz) and hygroscopic (0.0029 @ 10 GHz) conditions. Furthermore, the observed increase in Df after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic nature. Molecular simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains, after close stacking, impede the entry of water molecules. Despite sacrificing high-temperature resistance, the precursor exhibited enhanced solubility properties and could be processed into high-quality films. Our research unveils new insights into the relationship between flexibility and high-frequency dielectric loss, offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.
期刊介绍:
Chinese Journal of Polymer Science (CJPS) is a monthly journal published in English and sponsored by the Chinese Chemical Society and the Institute of Chemistry, Chinese Academy of Sciences. CJPS is edited by a distinguished Editorial Board headed by Professor Qi-Feng Zhou and supported by an International Advisory Board in which many famous active polymer scientists all over the world are included. The journal was first published in 1983 under the title Polymer Communications and has the current name since 1985.
CJPS is a peer-reviewed journal dedicated to the timely publication of original research ideas and results in the field of polymer science. The issues may carry regular papers, rapid communications and notes as well as feature articles. As a leading polymer journal in China published in English, CJPS reflects the new achievements obtained in various laboratories of China, CJPS also includes papers submitted by scientists of different countries and regions outside of China, reflecting the international nature of the journal.