{"title":"三种具有代表性的 WAXD/SAXS 图样,用于建立同素异形聚丙烯球粒中叠层的双峰结构概念","authors":"Kohji Tashiro, Hiroko Yamamoto, Ken-ichi Funaki, Hiroyasu Masunaga, Yuichi Miyake","doi":"10.1038/s41428-024-00893-x","DOIUrl":null,"url":null,"abstract":"Two types of lamellar stacking model were proposed for the inner structure of the melt-grown spherulites of isotactic polypropylene (iPP): the edge-on structure (flat lamellar planes stand on the spherulite plane, and a*-axis // growth direction of spherulite, b-axis ┴ spherulite plane, and c-axis // spherulite plane) and the flat-on structure (flat lamellar planes lay on the spherulite plane, a*-axis // growth direction, b-axis // spherulite plane, and c-axis ┴ spherulite plane). After a literature review was performed, the observed X-ray scattering data were not high quality and could not be used to establish these bimodal structures; moreover, the X-ray data analyses were not performed satisfactorily. As a result, the derivations of actual structures were still debatable. We performed simultaneous time-resolved WAXD/SAXS measurements using a synchrotron X-ray microbeam technique. The collected data were classified into three sets of completely different WAXD/SAXS patterns. Detailed quantitative analysis enabled the determination of the spatial orientations of the stacked lamellae and related crystallographic axes. Although the bimodal structure of iPP spherulites was considered to be a well-known and already-established concept for long years, the bimodal structure was successfully confirmed for the first time in the present study, making the concrete discussions on the growth mechanism of the iPP spherulites possible. The in situ wide-angle (WAXD) and small-angle X-ray scattering (SAXS) measurements have been performed using a synchrotron microbeam technique for the melt-isothermally-growing iPP spherulites. The thus-collected data were found to be classified into three sets of totally different WAXD/SAXS patterns, from which the three different orientation modes of the stacked lamellae and related crystallographic axes were deduced. These structural information allowed us to discuss the growth mechanism of stacked lamellae in the iPP spherulites from the microscopic point of view.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 5","pages":"491-503"},"PeriodicalIF":2.3000,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Three representative types of WAXD/SAXS patterns to establish the bimodal structure concept of stacked lamellae in isotactic polypropylene spherulites\",\"authors\":\"Kohji Tashiro, Hiroko Yamamoto, Ken-ichi Funaki, Hiroyasu Masunaga, Yuichi Miyake\",\"doi\":\"10.1038/s41428-024-00893-x\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Two types of lamellar stacking model were proposed for the inner structure of the melt-grown spherulites of isotactic polypropylene (iPP): the edge-on structure (flat lamellar planes stand on the spherulite plane, and a*-axis // growth direction of spherulite, b-axis ┴ spherulite plane, and c-axis // spherulite plane) and the flat-on structure (flat lamellar planes lay on the spherulite plane, a*-axis // growth direction, b-axis // spherulite plane, and c-axis ┴ spherulite plane). After a literature review was performed, the observed X-ray scattering data were not high quality and could not be used to establish these bimodal structures; moreover, the X-ray data analyses were not performed satisfactorily. As a result, the derivations of actual structures were still debatable. We performed simultaneous time-resolved WAXD/SAXS measurements using a synchrotron X-ray microbeam technique. The collected data were classified into three sets of completely different WAXD/SAXS patterns. Detailed quantitative analysis enabled the determination of the spatial orientations of the stacked lamellae and related crystallographic axes. Although the bimodal structure of iPP spherulites was considered to be a well-known and already-established concept for long years, the bimodal structure was successfully confirmed for the first time in the present study, making the concrete discussions on the growth mechanism of the iPP spherulites possible. 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引用次数: 0
摘要
针对熔融生长的异方性聚丙烯(iPP)球粒的内部结构,提出了两种层状堆积模型:边缘结构(扁平片层平面位于球粒体平面上,球粒体的生长方向为 a*轴//球粒体平面、b 轴┴球粒体平面和 c 轴//球粒体平面)和平面结构(扁平片层平面位于球粒体平面上,生长方向为 a*轴//球粒体平面、b 轴//球粒体平面和 c 轴┴球粒体平面)。在查阅文献后发现,观测到的 X 射线散射数据质量不高,无法用于确定这些双模结构;此外,X 射线数据分析的效果也不理想。因此,实际结构的推导仍有争议。我们使用同步辐射 X 射线微束技术同时进行了时间分辨 WAXD/SAXS 测量。收集到的数据被分为三组完全不同的 WAXD/SAXS 模式。通过详细的定量分析,确定了叠层的空间取向和相关的晶体学轴线。尽管 iPP 球粒的双峰结构多年来一直被认为是一个众所周知且早已确立的概念,但本研究首次成功证实了其双峰结构,从而使对 iPP 球粒的生长机制进行具体讨论成为可能。
Three representative types of WAXD/SAXS patterns to establish the bimodal structure concept of stacked lamellae in isotactic polypropylene spherulites
Two types of lamellar stacking model were proposed for the inner structure of the melt-grown spherulites of isotactic polypropylene (iPP): the edge-on structure (flat lamellar planes stand on the spherulite plane, and a*-axis // growth direction of spherulite, b-axis ┴ spherulite plane, and c-axis // spherulite plane) and the flat-on structure (flat lamellar planes lay on the spherulite plane, a*-axis // growth direction, b-axis // spherulite plane, and c-axis ┴ spherulite plane). After a literature review was performed, the observed X-ray scattering data were not high quality and could not be used to establish these bimodal structures; moreover, the X-ray data analyses were not performed satisfactorily. As a result, the derivations of actual structures were still debatable. We performed simultaneous time-resolved WAXD/SAXS measurements using a synchrotron X-ray microbeam technique. The collected data were classified into three sets of completely different WAXD/SAXS patterns. Detailed quantitative analysis enabled the determination of the spatial orientations of the stacked lamellae and related crystallographic axes. Although the bimodal structure of iPP spherulites was considered to be a well-known and already-established concept for long years, the bimodal structure was successfully confirmed for the first time in the present study, making the concrete discussions on the growth mechanism of the iPP spherulites possible. The in situ wide-angle (WAXD) and small-angle X-ray scattering (SAXS) measurements have been performed using a synchrotron microbeam technique for the melt-isothermally-growing iPP spherulites. The thus-collected data were found to be classified into three sets of totally different WAXD/SAXS patterns, from which the three different orientation modes of the stacked lamellae and related crystallographic axes were deduced. These structural information allowed us to discuss the growth mechanism of stacked lamellae in the iPP spherulites from the microscopic point of view.
期刊介绍:
Polymer Journal promotes research from all aspects of polymer science from anywhere in the world and aims to provide an integrated platform for scientific communication that assists the advancement of polymer science and related fields. The journal publishes Original Articles, Notes, Short Communications and Reviews.
Subject areas and topics of particular interest within the journal''s scope include, but are not limited to, those listed below:
Polymer synthesis and reactions
Polymer structures
Physical properties of polymers
Polymer surface and interfaces
Functional polymers
Supramolecular polymers
Self-assembled materials
Biopolymers and bio-related polymer materials
Polymer engineering.