Yujiao Zhai , Jing Zhang , Jiale Chen , Fenghao Shi , Yucai Li , Xin Wu , Chunling Xin , Yadong He
{"title":"Efficient fabrication of thermoplastic polyester elastomer foams with high expansion ratio and superior dimensional stability","authors":"Yujiao Zhai , Jing Zhang , Jiale Chen , Fenghao Shi , Yucai Li , Xin Wu , Chunling Xin , Yadong He","doi":"10.1016/j.supflu.2025.106784","DOIUrl":null,"url":null,"abstract":"<div><div>Due to its linear molecular chain structure, thermoplastic polyester elastomer (TPEE) exhibits inherently poor melt viscoelasticity and inadequate matrix strength. These limitations impair its foaming behavior and pose challenges in fabricating high-performance TPEE foams. Therefore, this work employed an epoxy chain extender (KL-E4370B) to modify TPEE. Results demonstrate that modified TPEE achieved a substantially enhanced branching degree, accompanied by a three orders of magnitude improvement in melt viscoelasticity. Notably, foaming temperature window broadened by 30 °C, while expansion ratio increased from 1.80 to 25.01. Moreover, modified TPEE exhibited a 29.96 % reduction in crystallinity, which enhanced gas permeability. This improvement effectively mitigated foam shrinkage while simultaneously accelerating recovery process. At 1.0 wt% KL-E4370B content, micro-crosslinked networks formed between molecular chains, enhancing matrix elastic modulus endowing TPEE foam with excellent self-recovery capability. Building on these results, this work successfully developed TPEE foams with simultaneous high expansion ratio and superior dimensional stability by regulating KL-E4370B content, establishing a novel strategy for engineering high-performance thermoplastic elastomer foams. Kohlrausch-Williams-Watts (KWW) model analysis further demonstrated that enhanced expansion ratio induced greater cell wall strain, which reduced the relaxation time of TPEE’s soft segments while narrowing their relaxation time distribution. This mechanistic explains the accelerated foam shrinkage behavior observed experimentally.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"228 ","pages":"Article 106784"},"PeriodicalIF":4.4000,"publicationDate":"2025-09-16","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/S0896844625002712","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}
引用次数: 0
Abstract
Due to its linear molecular chain structure, thermoplastic polyester elastomer (TPEE) exhibits inherently poor melt viscoelasticity and inadequate matrix strength. These limitations impair its foaming behavior and pose challenges in fabricating high-performance TPEE foams. Therefore, this work employed an epoxy chain extender (KL-E4370B) to modify TPEE. Results demonstrate that modified TPEE achieved a substantially enhanced branching degree, accompanied by a three orders of magnitude improvement in melt viscoelasticity. Notably, foaming temperature window broadened by 30 °C, while expansion ratio increased from 1.80 to 25.01. Moreover, modified TPEE exhibited a 29.96 % reduction in crystallinity, which enhanced gas permeability. This improvement effectively mitigated foam shrinkage while simultaneously accelerating recovery process. At 1.0 wt% KL-E4370B content, micro-crosslinked networks formed between molecular chains, enhancing matrix elastic modulus endowing TPEE foam with excellent self-recovery capability. Building on these results, this work successfully developed TPEE foams with simultaneous high expansion ratio and superior dimensional stability by regulating KL-E4370B content, establishing a novel strategy for engineering high-performance thermoplastic elastomer foams. Kohlrausch-Williams-Watts (KWW) model analysis further demonstrated that enhanced expansion ratio induced greater cell wall strain, which reduced the relaxation time of TPEE’s soft segments while narrowing their relaxation time distribution. This mechanistic explains the accelerated foam shrinkage behavior observed experimentally.
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.