{"title":"Processing Properties and Thermal Stability of Poly(vinyl chloride-co-vinyl acetate) by Experiments and Molecular Dynamics Simulations","authors":"Runyue Li, Daolei Lin, Shiqin Xu, Xingzheng Chen, Guofeng Tian, Dezhen Wu","doi":"10.1002/mats.202200054","DOIUrl":null,"url":null,"abstract":"<p>The effects of copolymerized monomer vinyl acetate (VAc) on processing properties and thermal stability of poly(vinyl chloride-co-vinyl acetate) (PVCA) are investigated via experiment and molecular dynamics simulation. Experimental results showed that PVCA with higher VAc content has larger loss tangent (tan<i>δ</i>), lower complex viscosity (<i>η</i>*), and glass transition temperature (Tg), which improved the processing properties of PVCA. A series of PVCA models are constructed to study the microstructure on the processing properties of PVCA, and the results showed the PVCA with higher VAc content exhibits larger molecular chain mobility and free volume fraction (FFV), smaller intermolecular interactions, and the mean square end-to-end distance (<Ree<sup>2</sup>>). Furthermore, the IR spectra of gas products indicated that thermal degradation of PVCA mainly generated hydrogen chloride (HCl), carboxylic acid, and aliphatic hydrocarbons between 200 and 500 °C, and the removal of HCl and carboxylic acid is almost simultaneous. The degradation models of PVCA chains demonstrated the C<span></span>Cl bond in vinyl chloride (VC) and C<span></span>O bond in VAc have similar thermal stability, which corresponded to the experimental results. In a word, the work provides a promising technique to study the structure and property of PVCA at molecular dynamic level.</p>","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Macromolecular Theory and Simulations","FirstCategoryId":"5","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/mats.202200054","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
The effects of copolymerized monomer vinyl acetate (VAc) on processing properties and thermal stability of poly(vinyl chloride-co-vinyl acetate) (PVCA) are investigated via experiment and molecular dynamics simulation. Experimental results showed that PVCA with higher VAc content has larger loss tangent (tanδ), lower complex viscosity (η*), and glass transition temperature (Tg), which improved the processing properties of PVCA. A series of PVCA models are constructed to study the microstructure on the processing properties of PVCA, and the results showed the PVCA with higher VAc content exhibits larger molecular chain mobility and free volume fraction (FFV), smaller intermolecular interactions, and the mean square end-to-end distance (<Ree2>). Furthermore, the IR spectra of gas products indicated that thermal degradation of PVCA mainly generated hydrogen chloride (HCl), carboxylic acid, and aliphatic hydrocarbons between 200 and 500 °C, and the removal of HCl and carboxylic acid is almost simultaneous. The degradation models of PVCA chains demonstrated the CCl bond in vinyl chloride (VC) and CO bond in VAc have similar thermal stability, which corresponded to the experimental results. In a word, the work provides a promising technique to study the structure and property of PVCA at molecular dynamic level.
期刊介绍:
Macromolecular Theory and Simulations is the only high-quality polymer science journal dedicated exclusively to theory and simulations, covering all aspects from macromolecular theory to advanced computer simulation techniques.