{"title":"通过基质强度调节和氮气引入控制超临界CO2发泡TPU系统的协同收缩","authors":"Huazhen Jiang, Panfeng Shao, Xia Liao","doi":"10.1016/j.supflu.2025.106789","DOIUrl":null,"url":null,"abstract":"<div><div>Thermoplastic polyurethane (TPU) foam has been applied widely in footwear, medical treatment, automotive, packaging, transportation, aerospace, etc. due to excellent properties such as elasticity, high impact strength, low temperature resistance. However, the significant shrinkage of TPU foam prepared by supercritical carbon dioxide (CO<sub>2</sub>) imposes a limitation on its wider application. In this study, TPU with a low hardness which is favorable for high expansion ratio was used as the matrix and TPU foams prepared by two approaches was investigated: regulating hardness and crystallinity by incorporating high hardness TPU, as well as, foaming with mixture blowing agents or re-foaming with N<sub>2</sub>. The results showed that the shrinkage behavior of TPU foam could be inhibited by regulating its hardness and crystallinity behavior. Furthermore, the final expansion ratio was improved significantly by re-foaming with N<sub>2</sub> in comparison to foaming with mixture blowing agent. It was ascertained that TPU foams first foamed with CO<sub>2</sub> and re-foamed with N₂ not only is optimal for achieving a final expansion ratio of approximately 11 times but also achieving the best elasticity and high compressive strength.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"228 ","pages":"Article 106789"},"PeriodicalIF":4.4000,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Synergistic shrinkage control in supercritical CO2 foamed TPU systems via matrix strength modulation and nitrogen introduction\",\"authors\":\"Huazhen Jiang, Panfeng Shao, Xia Liao\",\"doi\":\"10.1016/j.supflu.2025.106789\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Thermoplastic polyurethane (TPU) foam has been applied widely in footwear, medical treatment, automotive, packaging, transportation, aerospace, etc. due to excellent properties such as elasticity, high impact strength, low temperature resistance. However, the significant shrinkage of TPU foam prepared by supercritical carbon dioxide (CO<sub>2</sub>) imposes a limitation on its wider application. In this study, TPU with a low hardness which is favorable for high expansion ratio was used as the matrix and TPU foams prepared by two approaches was investigated: regulating hardness and crystallinity by incorporating high hardness TPU, as well as, foaming with mixture blowing agents or re-foaming with N<sub>2</sub>. The results showed that the shrinkage behavior of TPU foam could be inhibited by regulating its hardness and crystallinity behavior. Furthermore, the final expansion ratio was improved significantly by re-foaming with N<sub>2</sub> in comparison to foaming with mixture blowing agent. It was ascertained that TPU foams first foamed with CO<sub>2</sub> and re-foamed with N₂ not only is optimal for achieving a final expansion ratio of approximately 11 times but also achieving the best elasticity and high compressive strength.</div></div>\",\"PeriodicalId\":17078,\"journal\":{\"name\":\"Journal of Supercritical Fluids\",\"volume\":\"228 \",\"pages\":\"Article 106789\"},\"PeriodicalIF\":4.4000,\"publicationDate\":\"2025-09-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Supercritical Fluids\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0896844625002761\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Supercritical Fluids","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0896844625002761","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Synergistic shrinkage control in supercritical CO2 foamed TPU systems via matrix strength modulation and nitrogen introduction
Thermoplastic polyurethane (TPU) foam has been applied widely in footwear, medical treatment, automotive, packaging, transportation, aerospace, etc. due to excellent properties such as elasticity, high impact strength, low temperature resistance. However, the significant shrinkage of TPU foam prepared by supercritical carbon dioxide (CO2) imposes a limitation on its wider application. In this study, TPU with a low hardness which is favorable for high expansion ratio was used as the matrix and TPU foams prepared by two approaches was investigated: regulating hardness and crystallinity by incorporating high hardness TPU, as well as, foaming with mixture blowing agents or re-foaming with N2. The results showed that the shrinkage behavior of TPU foam could be inhibited by regulating its hardness and crystallinity behavior. Furthermore, the final expansion ratio was improved significantly by re-foaming with N2 in comparison to foaming with mixture blowing agent. It was ascertained that TPU foams first foamed with CO2 and re-foamed with N₂ not only is optimal for achieving a final expansion ratio of approximately 11 times but also achieving the best elasticity and high compressive strength.
期刊介绍:
The Journal of Supercritical Fluids is an international journal devoted to the fundamental and applied aspects of supercritical fluids and processes. Its aim is to provide a focused platform for academic and industrial researchers to report their findings and to have ready access to the advances in this rapidly growing field. Its coverage is multidisciplinary and includes both basic and applied topics.
Thermodynamics and phase equilibria, reaction kinetics and rate processes, thermal and transport properties, and all topics related to processing such as separations (extraction, fractionation, purification, chromatography) nucleation and impregnation are within the scope. Accounts of specific engineering applications such as those encountered in food, fuel, natural products, minerals, pharmaceuticals and polymer industries are included. Topics related to high pressure equipment design, analytical techniques, sensors, and process control methodologies are also within the scope of the journal.