{"title":"基于SAXS和流变学的拓扑约束对对称环双嵌段共聚物熔体混相增强的研究","authors":"Yuya Doi , Naoto Sakabe , Yoshiaki Takahashi , Atsushi Takano , Yushu Matsushita","doi":"10.1016/j.polymer.2025.129092","DOIUrl":null,"url":null,"abstract":"<div><div>Miscibility between components for a compositionally symmetric ring diblock copolymer consisting of polystyrene (S) and polyisoprene (I) with a total molecular weight of <em>M</em><sub>n,total</sub> = 23 kg/mol (R-SI-23) in melt was investigated by small-angle X-ray scattering (SAXS) and rheological measurements under heating in comparison with the corresponding linear SI diblock (L-SI-22) and ISI triblock (tele-ISI-23). From SAXS measurements, L-SI-22 exhibits even-order sharp peaks, confirming a lamellar microphase-separated structure or it is in an ordered state at a relatively low temperature of 120 °C, while both R-SI-23 and tele-ISI-23 exhibit a broad correlation hole peak each, suggesting that they are in a disordered state. Dynamic viscoelasticity measurements also revealed that L-SI-22 exhibits an order-disorder transition (ODT) at around 260 °C, while R-SI-23 and tele-ISI-23 show disordered-state behavior even at low temperatures around 120 °C. SAXS profiles of R-SI-23 and tele-ISI-23 with a broad correlation hole peak are analyzed for scattering functions based on the random phase approximation (RPA) theory focusing on the chain connecting manners. The analytical results suggest that R-SI-23 has a lower effective Flory-Huggins interaction parameter, <em>χ</em><sub>eff</sub>, than tele-ISI-23. This result could be attributed to the topological constraints in ring polymer melts, which forces the segments of S and I components in a ring molecule to bring closer together, resulting in enhancing miscibility.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"338 ","pages":"Article 129092"},"PeriodicalIF":4.5000,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Miscibility enhancement in a symmetric ring diblock copolymer melt due to topological constraint studied by SAXS and rheology\",\"authors\":\"Yuya Doi , Naoto Sakabe , Yoshiaki Takahashi , Atsushi Takano , Yushu Matsushita\",\"doi\":\"10.1016/j.polymer.2025.129092\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Miscibility between components for a compositionally symmetric ring diblock copolymer consisting of polystyrene (S) and polyisoprene (I) with a total molecular weight of <em>M</em><sub>n,total</sub> = 23 kg/mol (R-SI-23) in melt was investigated by small-angle X-ray scattering (SAXS) and rheological measurements under heating in comparison with the corresponding linear SI diblock (L-SI-22) and ISI triblock (tele-ISI-23). From SAXS measurements, L-SI-22 exhibits even-order sharp peaks, confirming a lamellar microphase-separated structure or it is in an ordered state at a relatively low temperature of 120 °C, while both R-SI-23 and tele-ISI-23 exhibit a broad correlation hole peak each, suggesting that they are in a disordered state. Dynamic viscoelasticity measurements also revealed that L-SI-22 exhibits an order-disorder transition (ODT) at around 260 °C, while R-SI-23 and tele-ISI-23 show disordered-state behavior even at low temperatures around 120 °C. SAXS profiles of R-SI-23 and tele-ISI-23 with a broad correlation hole peak are analyzed for scattering functions based on the random phase approximation (RPA) theory focusing on the chain connecting manners. The analytical results suggest that R-SI-23 has a lower effective Flory-Huggins interaction parameter, <em>χ</em><sub>eff</sub>, than tele-ISI-23. This result could be attributed to the topological constraints in ring polymer melts, which forces the segments of S and I components in a ring molecule to bring closer together, resulting in enhancing miscibility.</div></div>\",\"PeriodicalId\":405,\"journal\":{\"name\":\"Polymer\",\"volume\":\"338 \",\"pages\":\"Article 129092\"},\"PeriodicalIF\":4.5000,\"publicationDate\":\"2025-09-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Polymer\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S003238612501078X\",\"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":"Polymer","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S003238612501078X","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
摘要
采用小角x射线散射(SAXS)和加热流变学测量方法,研究了总分子量为Mn,总分子量为23 kg/mol (R-SI-23)的聚苯乙烯(S)和聚异戊二烯(I)组成的对称环状二嵌段共聚物在熔体中的混溶性,并与相应的线性SI二嵌段(L-SI-22)和ISI三嵌段(tele- SI-23)进行了比较。从SAXS测量中,L-SI-22呈现出均匀有序的尖峰,证实了层状微相分离结构或在相对较低的120℃下处于有序状态,而R-SI-23和tele- si -23均呈现出宽相关空穴峰,表明它们处于无序状态。动态粘弹性测量还表明,L-SI-22在260℃左右表现出有序-无序转变(ODT),而R-SI-23和tele- si -23即使在120℃左右的低温下也表现出无序状态行为。基于随机相位近似(RPA)理论,以链连接方式为重点,分析了具有宽相关空穴峰的R-SI-23和tele- si -23的散射函数。分析结果表明,R-SI-23的有效Flory-Huggins相互作用参数(χeff)低于tele- si -23。这一结果可能归因于环状聚合物熔体中的拓扑约束,这迫使环状分子中的S和I组分片段靠得更近,从而增强了混相性。
Miscibility enhancement in a symmetric ring diblock copolymer melt due to topological constraint studied by SAXS and rheology
Miscibility between components for a compositionally symmetric ring diblock copolymer consisting of polystyrene (S) and polyisoprene (I) with a total molecular weight of Mn,total = 23 kg/mol (R-SI-23) in melt was investigated by small-angle X-ray scattering (SAXS) and rheological measurements under heating in comparison with the corresponding linear SI diblock (L-SI-22) and ISI triblock (tele-ISI-23). From SAXS measurements, L-SI-22 exhibits even-order sharp peaks, confirming a lamellar microphase-separated structure or it is in an ordered state at a relatively low temperature of 120 °C, while both R-SI-23 and tele-ISI-23 exhibit a broad correlation hole peak each, suggesting that they are in a disordered state. Dynamic viscoelasticity measurements also revealed that L-SI-22 exhibits an order-disorder transition (ODT) at around 260 °C, while R-SI-23 and tele-ISI-23 show disordered-state behavior even at low temperatures around 120 °C. SAXS profiles of R-SI-23 and tele-ISI-23 with a broad correlation hole peak are analyzed for scattering functions based on the random phase approximation (RPA) theory focusing on the chain connecting manners. The analytical results suggest that R-SI-23 has a lower effective Flory-Huggins interaction parameter, χeff, than tele-ISI-23. This result could be attributed to the topological constraints in ring polymer melts, which forces the segments of S and I components in a ring molecule to bring closer together, resulting in enhancing miscibility.
期刊介绍:
Polymer is an interdisciplinary journal dedicated to publishing innovative and significant advances in Polymer Physics, Chemistry and Technology. We welcome submissions on polymer hybrids, nanocomposites, characterisation and self-assembly. Polymer also publishes work on the technological application of polymers in energy and optoelectronics.
The main scope is covered but not limited to the following core areas:
Polymer Materials
Nanocomposites and hybrid nanomaterials
Polymer blends, films, fibres, networks and porous materials
Physical Characterization
Characterisation, modelling and simulation* of molecular and materials properties in bulk, solution, and thin films
Polymer Engineering
Advanced multiscale processing methods
Polymer Synthesis, Modification and Self-assembly
Including designer polymer architectures, mechanisms and kinetics, and supramolecular polymerization
Technological Applications
Polymers for energy generation and storage
Polymer membranes for separation technology
Polymers for opto- and microelectronics.