{"title":"大块非晶聚合物和相关玻璃形成系统的多重介电弛豫的多态势垒模型","authors":"Vittorio Rosato, Graham Williams","doi":"10.1016/0378-4487(81)80016-7","DOIUrl":null,"url":null,"abstract":"<div><p>The dynamics of a fluctuation model, broadly based on an earlier model of Bueche, is considered for the motion of a molecule in a glass-forming material. The molecule is assumed to occupy a number of local states in four equivalent manifolds and relaxes by motion between the local states and between manifolds. The dipole-moment correlation function, and hence the dielectric relaxation behaviour, is calculated for a range of relaxation parameters. Two general processes are found being (i) a family of ‘fast’ relaxation modes due to motion between the local states and (ii) a single ‘slow’ relaxation mode due to motion out of one manifold into adjacent manifolds. This pattern is qualitatively in accord with observations of and α processes in glass-forming systems but the observed α-processes are generally rather broader than a ‘slow’ single relaxation-time process which results from the present model.</p></div>","PeriodicalId":100049,"journal":{"name":"Advances in Molecular Relaxation and Interaction Processes","volume":"20 4","pages":"Pages 233-248"},"PeriodicalIF":0.0000,"publicationDate":"1981-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4487(81)80016-7","citationCount":"4","resultStr":"{\"title\":\"A multi-state barrier model for the multiple dielectric relaxations of bulk amorphous polymers and related glass-forming systems\",\"authors\":\"Vittorio Rosato, Graham Williams\",\"doi\":\"10.1016/0378-4487(81)80016-7\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The dynamics of a fluctuation model, broadly based on an earlier model of Bueche, is considered for the motion of a molecule in a glass-forming material. The molecule is assumed to occupy a number of local states in four equivalent manifolds and relaxes by motion between the local states and between manifolds. The dipole-moment correlation function, and hence the dielectric relaxation behaviour, is calculated for a range of relaxation parameters. Two general processes are found being (i) a family of ‘fast’ relaxation modes due to motion between the local states and (ii) a single ‘slow’ relaxation mode due to motion out of one manifold into adjacent manifolds. This pattern is qualitatively in accord with observations of and α processes in glass-forming systems but the observed α-processes are generally rather broader than a ‘slow’ single relaxation-time process which results from the present model.</p></div>\",\"PeriodicalId\":100049,\"journal\":{\"name\":\"Advances in Molecular Relaxation and Interaction Processes\",\"volume\":\"20 4\",\"pages\":\"Pages 233-248\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1981-08-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1016/0378-4487(81)80016-7\",\"citationCount\":\"4\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Advances in Molecular Relaxation and Interaction Processes\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/0378448781800167\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advances in Molecular Relaxation and Interaction Processes","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0378448781800167","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
A multi-state barrier model for the multiple dielectric relaxations of bulk amorphous polymers and related glass-forming systems
The dynamics of a fluctuation model, broadly based on an earlier model of Bueche, is considered for the motion of a molecule in a glass-forming material. The molecule is assumed to occupy a number of local states in four equivalent manifolds and relaxes by motion between the local states and between manifolds. The dipole-moment correlation function, and hence the dielectric relaxation behaviour, is calculated for a range of relaxation parameters. Two general processes are found being (i) a family of ‘fast’ relaxation modes due to motion between the local states and (ii) a single ‘slow’ relaxation mode due to motion out of one manifold into adjacent manifolds. This pattern is qualitatively in accord with observations of and α processes in glass-forming systems but the observed α-processes are generally rather broader than a ‘slow’ single relaxation-time process which results from the present model.