{"title":"具有预留什晶和不同缠结度的低缠结超高分子量聚乙烯凝胶薄膜在拉伸过程中的结构演变","authors":"","doi":"10.1016/j.polymer.2024.127592","DOIUrl":null,"url":null,"abstract":"<div><p>Shish-kebab crystal is a crucial crystalline morphology in polymers, and its formation and evolution are paramount for achieving high-performance materials. In this study, using UHMWPE as an example, we employed precise temperature control in the gel molding process to prepare low-entangled UHMWPE gel films containing reserved shish crystals, Distinguished from other molding systems, gel molding, due to the presence of small-molecule solvents, not only reduces the entanglement degree of the system but also provides a favorable environment for molecular chain disentanglement, and thus is considered as a low-entanglement system that is easily disentangled. We investigated the structural evolution of the films at different stretching temperatures by employing in-situ WAXD, SAXS, USAXS, along with ex-situ SEM and DSC methods. Furthermore, the impact of entanglement degree on the evolution of crystal structures was explored through the change of molecular weight. 2D-USAXS results reveal the longer stripe scattering signals than previous studies, indicating a more pronounced ordered arrangement of shish crystals. Simultaneously, we discovered that only when molecular chains with an appropriate degree of entanglement were induced to disentangle by stretching with the presence of small-molecule solvents can the high orientation of crystals be facilitated, thereby promoting the evolution of crystal structure. Reserved shish crystals can induce crystal orientation during stretching and facilitate structural evolution. Building upon earlier investigations, this study innovatively through the dual-factor (the molecular weight and stretching temperature) control of the suitable entanglement degree and disentanglement conditions, allowing for reasonable control of the growth and evolution of shish-kebab crystals in low-entangled systems.</p></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":null,"pages":null},"PeriodicalIF":4.1000,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Structural evolution of low-entangled UHMWPE gel films with reserved shish crystals and different entanglement degrees during stretching\",\"authors\":\"\",\"doi\":\"10.1016/j.polymer.2024.127592\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Shish-kebab crystal is a crucial crystalline morphology in polymers, and its formation and evolution are paramount for achieving high-performance materials. In this study, using UHMWPE as an example, we employed precise temperature control in the gel molding process to prepare low-entangled UHMWPE gel films containing reserved shish crystals, Distinguished from other molding systems, gel molding, due to the presence of small-molecule solvents, not only reduces the entanglement degree of the system but also provides a favorable environment for molecular chain disentanglement, and thus is considered as a low-entanglement system that is easily disentangled. We investigated the structural evolution of the films at different stretching temperatures by employing in-situ WAXD, SAXS, USAXS, along with ex-situ SEM and DSC methods. Furthermore, the impact of entanglement degree on the evolution of crystal structures was explored through the change of molecular weight. 2D-USAXS results reveal the longer stripe scattering signals than previous studies, indicating a more pronounced ordered arrangement of shish crystals. Simultaneously, we discovered that only when molecular chains with an appropriate degree of entanglement were induced to disentangle by stretching with the presence of small-molecule solvents can the high orientation of crystals be facilitated, thereby promoting the evolution of crystal structure. Reserved shish crystals can induce crystal orientation during stretching and facilitate structural evolution. Building upon earlier investigations, this study innovatively through the dual-factor (the molecular weight and stretching temperature) control of the suitable entanglement degree and disentanglement conditions, allowing for reasonable control of the growth and evolution of shish-kebab crystals in low-entangled systems.</p></div>\",\"PeriodicalId\":405,\"journal\":{\"name\":\"Polymer\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.1000,\"publicationDate\":\"2024-09-04\",\"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/S0032386124009285\",\"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/S0032386124009285","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
刹那晶体是聚合物中一种重要的结晶形态,它的形成和演化对实现高性能材料至关重要。有别于其他成型体系,凝胶成型由于小分子溶剂的存在,不仅降低了体系的缠结度,而且为分子链的解缠结提供了有利的环境,因此被认为是一种易于解缠结的低缠结体系。我们采用原位 WAXD、SAXS、USAXS 以及原位 SEM 和 DSC 方法研究了薄膜在不同拉伸温度下的结构演变。此外,还通过分子量的变化探讨了缠结度对晶体结构演变的影响。2D-USAXS 结果显示,与之前的研究相比,条纹散射信号更长,表明菱形晶体的有序排列更明显。同时,我们发现只有在小分子溶剂存在的情况下,通过拉伸诱导具有适当纠缠度的分子链解离,才能促进晶体的高取向,从而促进晶体结构的演化。保留的shish晶体可在拉伸过程中诱导晶体取向并促进结构演化。在早期研究的基础上,本研究创新性地通过双因素(分子量和拉伸温度)控制合适的纠缠度和解纠缠条件,从而合理控制了低纠缠体系中什-克巴晶体的生长和演化。
Structural evolution of low-entangled UHMWPE gel films with reserved shish crystals and different entanglement degrees during stretching
Shish-kebab crystal is a crucial crystalline morphology in polymers, and its formation and evolution are paramount for achieving high-performance materials. In this study, using UHMWPE as an example, we employed precise temperature control in the gel molding process to prepare low-entangled UHMWPE gel films containing reserved shish crystals, Distinguished from other molding systems, gel molding, due to the presence of small-molecule solvents, not only reduces the entanglement degree of the system but also provides a favorable environment for molecular chain disentanglement, and thus is considered as a low-entanglement system that is easily disentangled. We investigated the structural evolution of the films at different stretching temperatures by employing in-situ WAXD, SAXS, USAXS, along with ex-situ SEM and DSC methods. Furthermore, the impact of entanglement degree on the evolution of crystal structures was explored through the change of molecular weight. 2D-USAXS results reveal the longer stripe scattering signals than previous studies, indicating a more pronounced ordered arrangement of shish crystals. Simultaneously, we discovered that only when molecular chains with an appropriate degree of entanglement were induced to disentangle by stretching with the presence of small-molecule solvents can the high orientation of crystals be facilitated, thereby promoting the evolution of crystal structure. Reserved shish crystals can induce crystal orientation during stretching and facilitate structural evolution. Building upon earlier investigations, this study innovatively through the dual-factor (the molecular weight and stretching temperature) control of the suitable entanglement degree and disentanglement conditions, allowing for reasonable control of the growth and evolution of shish-kebab crystals in low-entangled systems.
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.