Polymer最新文献_第9页

Highly insulating LDPE compounds at high temperature: The effect of electron-withdrawing PCBM on DC dielectric properties

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-23 DOI: 10.1016/j.polymer.2025.128052

Minhui Zhu, Daomin Min, Shihang Wang, Yihang Jiang

Low-density polyethylene (LDPE) is an excellent insulating material that ensures the safe and reliable operation of high-voltage direct current (HVDC) cables. The insulation properties of LDPE can be improved by doping with voltage stabilizers. Due to its electron-withdrawing property, [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) has the potential to be used as a voltage stabilizer to improve the DC insulation performance of LDPE, especially the high temperature insulation performance of cable insulation. Therefore, the impact of PCBM on carrier trap characteristics and micro charge transport at high temperatures and high fields requires further study. LDPE is used as the matrix material to prepare composites with concentrations of 0.5 and 1 wt%. The experimental results show that the Weibull characteristic breakdown strength can be increased by 10.5 % and the DC electrical conductivity can be reduced by 73.6 % at 90 °C, when the PCBM doping concentration is 0.5 wt%. These results can be explained by trap characteristics and molecular chain displacement. It reveals that the introduction of PCBM can effectively increase the trap density, which can capture more charge carriers, resulting in a decrease in carrier mobility and electrical conductivity. Quantum chemical calculations indicate that owing to the high electron affinity and low ionization potential of PCBM, it is more prone to attracting and capturing electrons, thereby efficiently absorbing high-energy electron energy. Moreover, PCBM makes the amorphous region more tightly ordered, which manifests as an improvement in crystallinity. It also enhances the friction coefficient of the molecular chain and suppresses the molecular chain displacement in LDPE, which is verified by charge transport and molecular displacement modulated model simulations. This study provides a new method for improving the properties of cable insulation materials.

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引用次数: 0

Preparation of high elastic bimodal cells biodegradable foam 高弹性双峰细胞可生物降解泡沫的制备

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127987

Hanlin Tian , Zepeng Wang , Jinshuo Yu , Yan Zhao , Hongwei Pan , Junjia Bian , Huili Yang , Zhibing Wang , Huiliang Zhang

Poly(butylene adipate-co-terephthalate) (PBAT) and polybutylene succinate (PBS) are advanced biodegradable thermoplastic elastomer with excellent application prospects. There is a growing interest in developing PBAT foam products as effective alternatives to traditional foams for sports, shock absorption, and safety protection. In this study, high compression strength and high elasticity PBAT/PBS foam materials was prepared by supercritical CO₂ foam, the effects of the crystallization nucleation agent TMC and the chain extender ADR on crystallization and melt strength of blends was investigated by varying temperature-pressure modes (VT-PM). The rheological results showed that with the increase of ADR, the storage modulus and viscosity of PBAT/PBS blends increased significantly, transitioning from a viscous liquid-like to an elastic state. TMC could promote polymer crystallization, crystal size reduced, and small size cell was obtained during the foaming. Finally, a high elastic foam T/S-0.2-1.5 with 12 times and the compressive strength about 0.59 MPa and energy loss of 14.3 % can be prepared due to synergistic effect of ADR and TMC. This provides a promising application prospect for biodegradable foams.

聚己二酸丁二酸酯（PBAT）和聚丁二酸丁二酸酯（PBS）是一种先进的可生物降解热塑性弹性体，具有良好的应用前景。人们对开发PBAT泡沫产品越来越感兴趣，它可以作为传统泡沫的有效替代品，用于运动、减震和安全保护。采用超临界CO2泡沫法制备了高抗压强度、高弹性的PBAT/PBS泡沫材料，通过变温-变压模式（VT-PM）研究了结晶成核剂TMC和扩链剂ADR对共混物结晶和熔融强度的影响。流变学结果表明，随着ADR的增加，PBAT/PBS共混物的存储模量和粘度显著增加，由粘性类液体状态过渡到弹性状态。TMC能促进聚合物的结晶，使聚合物的结晶尺寸减小，发泡时得到小尺寸的晶胞。最后，由于ADR和TMC的协同作用，可制得高弹性泡沫T/S-0.2-1.5，其抗压强度为TMC的12倍，抗压强度约为0.59 MPa，能量损失为14.3%。这为生物降解泡沫材料提供了广阔的应用前景。

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引用次数: 0

Transformation of ethylene vinyl alcohol copolymer from a glassy state to a rubber state through post ester-exchange modification 乙烯乙烯醇共聚物通过酯交换后改性从玻璃态转变为橡胶态

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127993

Zhenjing Zhou , Yihao Meng , Jiang Wu , Jieting Zhou , Xi Yu , Ningbo Yi , Qinghua Wu , Yancheng Wu , Jialin Zhang , Longfei Fan , Juxian Zhang , Feng Gan

Polyolefins and their derivatives can be modified in both phase-state and function through post-modification techniques. This study presented a novel ethylene-vinyl alcohol-acetoacetate ester copolymer (EVOH-A), synthesized via a simple post ester-exchange method. The incorporation of acetoacetic ester not only alters the polymer's phase state but also enhances its potential for further functionalization. Two-dimensional infrared spectroscopy and molecular dynamics simulations showed that the ester-exchange modification weakens hydrogen bonds in EVOH, leading to a more amorphous structure. Thermal analysis reveals that the glass transition temperature (T_g) of modified EVOH decreases from 30 °C (EVOH) to −3 °C (EVOH-A4), indicating a transformation from a glassy to a rubbery state of polymers. The tensile strength and Young's modulus of the modified EVOH-A films decrease, while tensile elongation significantly increases. Additionally, this work demonstrates the application of modified polymers in the Hantzsch reaction, endowing the photoluminescence and hydrophobicity of polymers. This study introduces a new EVOH modification method with significant potential for developing multifunctional polyolefin materials.

聚烯烃及其衍生物可通过后改性技术改变相态和功能。本研究介绍了一种新型乙烯-乙烯醇-乙酰乙酸酯共聚物（EVOH-A），它是通过一种简单的酯交换后方法合成的。乙酰乙酸酯的加入不仅改变了聚合物的相态，还增强了其进一步官能化的潜力。二维红外光谱和分子动力学模拟显示，酯交换改性削弱了 EVOH 中的氢键，使其结构更加无定形。热分析表明，改性 EVOH 的玻璃化转变温度 (Tg) 从 30 oC（EVOH）降至 -3 oC（EVOH-A4），表明聚合物从玻璃态转变为橡胶态。改性 EVOH-A 薄膜的拉伸强度和杨氏模量降低，而拉伸伸长率显著增加。此外，这项研究还证明了改性聚合物在 Hantzsch 反应中的应用，赋予了聚合物光致发光和疏水性。这项研究介绍了一种新的 EVOH 改性方法，它在开发多功能聚烯烃材料方面具有巨大潜力。

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引用次数: 0

A biodegradable gel polymer membrane derived from poly-gamma-glutamic acid for high-rate and long-lifespan sodium metal batteries 用于高倍率和长寿命钠金属电池的聚γ -谷氨酸可降解凝胶聚合物膜

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127977

Haichuan Cao, Kaixian Wang, Zheng Wu, Zhuoyuan Zheng, Yawen Li, Jie Zhou, Yusong Zhu

Sodium metal battery (SMB) technology is gaining increasing popularity due to its potential for cost-effective and sustainable energy storage solutions. However, a critical challenge hindering its commercialization is the development of safe, eco-friendly and high-performance electrolyte systems. In this study, poly-gamma-glutamic acid (γ-PGA)-based gel polymer membrane (GPM) for SMBs (denoted as γ-PP64) is obtained using a mixed solvent method. The resulting γ-PP64 membrane with the thickness of about 30 μm exhibits a porous structure that significantly enhances its electrolytes absorption to 144.4 % and excellent thermal stability to 150 °C. This structural innovation also facilitates the migration of Na ⁺ ions (up to 0.11 mS cm⁻¹) and high transference number of 0.536, which promotes reversible and uniform sodium deposition and dissolution. During cycling tests at 0.5 C, the corresponding Na/γ-PP64 GPM/Na₃V₂(PO₄)₃ full cell demonstrates an initial capacity of 103 mAh g⁻¹ and a 92.8 % capacity retention. Additionally, the γ-PP64 GPM cell records a capacity of 87.3 mAh g⁻¹ after 1100 cycles at a high rate of 5 C. The findings highlight the potential of biodegradable material-based GPM to enhance the performance and longevity of SMBs, thereby paving the way for their commercialization and contributing to environmental sustainability goals in energy storage applications.

钠金属电池（SMB）技术由于其具有成本效益和可持续能源存储解决方案的潜力而越来越受欢迎。然而，阻碍其商业化的一个关键挑战是开发安全、环保和高性能的电解质系统。本研究采用混合溶剂法制备了多γ-谷氨酸（γ-PGA）基中小企业凝胶聚合物膜（GPM）（记为γ-PP64）。所制得的γ-PP64膜厚度约为30 μm，具有多孔结构，电解质吸收率提高至144.4%，在150℃时具有良好的热稳定性。这种结构的创新也促进了Na+离子的迁移（迁移量可达0.11 mS cm-1）和0.536的高迁移数，促进了钠的可逆均匀沉积和溶解。在0.5℃循环测试中，相应的Na/γ-PP64 GPM/Na3V2(PO4)3全电池的初始容量为103 mAh g-1，容量保持率为92.8%。此外，γ-PP64 GPM电池在5℃的高倍率下，经过1100次循环后的容量为87.3 mAh g-1。研究结果突出了基于可生物降解材料的GPM在提高smb性能和寿命方面的潜力，从而为其商业化铺平了道路，并有助于实现储能应用中的环境可持续性目标。

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引用次数: 0

Healable and recyclable poly(urethane-urea) elastomers with high mechanical strength, extreme toughness, and excellent crack tolerance via a supramolecular self-assembly strategy for strain sensor application 可愈合和可回收的聚（聚氨酯-尿素）弹性体具有高机械强度，极端韧性和优异的抗裂性，通过超分子自组装策略应用于应变传感器

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127994

Xionghui Wu , Xinyi Xiong , Yichao Hu , Qihui Tang , Yaling Lin , Anqiang Zhang

Conductive materials with high strength, high toughness and excellent crack resistance are important components of high-performance wearable electronic devices. Wearable strain sensors require robust materials to ensure durability and stability, as well as a wide strain range, to expand their applications. In this work, inspired by the unique dense hydrogen bond arrays in spider silk, a multifunctional supramolecular poly(urethane-urea) (SiPUU-IPDA) elastomers integrating high mechanical strength, toughness and excellent crack resistance have been successfully synthesized. Relying on high-density hydrogen bond arrays, the SiPUU-IPDA elastomers exhibited a high mechanical strength of 71.2 MPa, a toughness of 734.3 MJ/m³ and a fracture energy of up to 124.1 kJ/m². Owing to the dynamic reversibility of the hydrogen bonds arrays, the SiPUU-IPDA elastomers exhibited excellent healability and recyclability. Moreover, a crack tolerance, recyclability and strain sensor composite (SiPUU-IPDA₂/TA/CNTs) is prepared using the SiPUU-IPDA₂ elastomer as the matrix. These SiPUU-IPDA elastomers offer great potential for the design and preparation of robust materials with healability and recyclability for various applications that require high strength and toughness.

具有高强度、高韧性和优异抗裂性能的导电材料是高性能可穿戴电子器件的重要组成部分。可穿戴应变传感器需要坚固的材料来确保耐用性和稳定性，以及广泛的应变范围，以扩大其应用范围。在这项工作中，受蜘蛛丝中独特的致密氢键阵列的启发，成功合成了一种集高机械强度、韧性和优异抗裂性于一体的多功能超分子聚氨酯-尿素（SiPUU-IPDA）弹性体。基于高密度氢键阵列，SiPUU-IPDA弹性体的机械强度为71.2 MPa，韧性为734.3 MJ/m3，断裂能高达124.1 kJ/m2。由于氢键阵列的动态可逆性，SiPUU-IPDA弹性体具有良好的可修复性和可回收性。以SiPUU-IPDA2弹性体为基体，制备了一种耐裂、可回收、应变传感器复合材料（SiPUU-IPDA2/TA/CNTs）。这些SiPUU-IPDA弹性体为设计和制备具有可治愈性和可回收性的坚固材料提供了巨大的潜力，适用于需要高强度和韧性的各种应用。

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引用次数: 0

Wood flour/-poly(methyl methacrylate)/capric acid polymer composites as form-stable phase change materials for thermal energy management 木粉/聚甲基丙烯酸甲酯/癸酸聚合物复合材料在热能管理中的形式稳定相变材料

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127989

Ahmet Can , Osman Gencel , Ahmet Sarı , Gökhan Hekimoğlu

This study focuses on the preparation and characterization of wood flour (WF)/polymethyl methacrylate (PMMA)/capric acid (CA) composite form-stable phase change materials (PCM) prepared by PMMA modification method, with WF selected as the support material. The surface morphology (scanning electron microscopy SEM), chemical structure (Fourier transform infrared spectrometer, FTIR), crystalline structure (X-ray diffraction, XRD), phase change properties (differential scanning calorimeter, DSC), thermal stability (thermogravimetric analysis, TGA) of the prepared WF/PMMA/CA composite form-stable PCMs were investigated. SEM analysis demonstrates that the wood surfaces were coated with CA and PMMA. As the PMMA ratio on the surfaces increased, the amount of leaching decreased. FTIR and XRD results suggested that the structure of the PMMA polymer is also seen in the prepared composite materials. There was no chemical reaction but only physical interactions between WF and CA. The generated WF/PMMA/CA composite PCMs exhibited high latent heats and an appropriate phase change temperature range; in particular, the WF/PMMA/CA (1/1/2)'s highest latent heats throughout the melting and freezing processes were 95.08 J/g and 91.29 J/g, respectively. Using higher proportions of CA provides more energy storage capacity; however, the contribution of PMMA further enhances this effect, strengthening the energy storage performance. Thermal conductivity increased by 63.9 % in WF/PMMA/CA (1/1/2).

本研究以木粉(WF)/聚甲基丙烯酸甲酯(PMMA)/癸酸（CA）为支撑材料，采用PMMA改性法制备了木粉(WF)/聚甲基丙烯酸甲酯(PMMA)/癸酸（CA）复合形式稳定相变材料（PCM），并对其进行了表征。研究了制备的WF/PMMA/CA复合稳形PCMs的表面形貌（扫描电镜SEM）、化学结构（傅里叶变换红外光谱仪FTIR）、晶体结构（x射线衍射仪XRD）、相变性能（差示扫描量热仪DSC）、热稳定性（热重分析TGA）。SEM分析表明，木材表面涂覆了CA和PMMA。随着表面PMMA比例的增加，浸出量减少。红外光谱（FTIR）和x射线衍射（XRD）结果表明，所制备的复合材料中也可以看到PMMA聚合物的结构。制备的WF/PMMA/CA复合相变材料具有较高的潜热和适宜的相变温度范围；其中WF/PMMA/CA（1/ 2 /2）在融化和冻结过程中的最高潜热分别为95.08 J/g和91.29 J/g。采用较高比例的CA可提供更大的储能容量；然而，PMMA的贡献进一步增强了这种效应，增强了储能性能。WF/PMMA/CA的导热系数提高了63.9%（1/1/2）。

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引用次数: 0

Effect of trimethylphenylammonium tribromide/carbonaceous nanosystems on mechanical and thermal properties of unsaturated polyester resin: Experimental and computational perspective 三甲基苯基三溴化铵/碳基纳米体系对不饱和聚酯树脂力学和热性能的影响：实验和计算视角

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127982

Smitha Roy , Bejoy Francis , Sajith Menon , Saithalavi Anas , Kollappillil S. Krishnakumar , Aravind Krishnan

A systematic study on the mechanical and thermal properties of unsaturated polyester resin (UPR) on adding Trimethylphenylammoniumtribromide (TMPTB), a relatively unexplored ionic system, as a modifier in combination with various carbonaceous nanosystems are described. Among the various systems [graphene (G), graphene oxide (GO) and carbon nanotube (CNT)] explored, an exceptional increase of 45 % in the tensile strength of unsaturated polyester resin (UPR) was observed with TMPTB in combination with graphene (G). A detailed computational analysis (DFT and QTAIM) revealed that a mutual bonding association between TMPTB, G and UPR was responsible for this promising result; further evidenced by TEM analysis. The increase in tensile strength was accompanied by an increase in thermal stability, Tg and storage modulus of the system, as observed in TGA and DMA studies. This work not only introduce a new class of modifier system for enhancing the mechanical strength of UPR; but also highlight the significance of computational analysis (seldom used in this area) in exploring the intramolecular forces (or factors) responsible for such observations, and thereby promoting new horizon in the upcoming research for design and development of novel modifiers for specific applications.

本文系统地研究了以三溴化三甲基苯基铵（TMPTB）离子体系为改性剂，与多种碳质纳米体系结合制备不饱和聚酯树脂（UPR）的力学性能和热性能。在研究的各种体系[石墨烯(G)、氧化石墨烯（GO）和碳纳米管（CNT）]中，TMPTB与石墨烯(G)结合后，不饱和聚酯树脂（UPR）的抗拉强度异常提高了45%。详细的计算分析（DFT和QTAIM）表明，TMPTB、G和UPR之间的相互键合关系是这一有希望的结果的原因；TEM分析进一步证明。拉伸强度的增加伴随着系统的热稳定性、Tg和储存模量的增加，这在TGA和DMA研究中观察到。本工作不仅为提高UPR的机械强度引入了一类新的改性剂体系；但也强调了计算分析（在这一领域很少使用）在探索导致这种观察的分子内力（或因素）方面的重要性，从而为即将到来的研究提供了新的视野，为特定应用设计和开发新的改性剂。

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引用次数: 0

In-depth understanding of the role of methanesulfonic acid in nitrile group conversion of PIM-1 深入了解甲基磺酸在PIM-1腈基转化中的作用

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127992

Min Zhao, Aidi Wang, Caili Zhang

Polymers of intrinsic microporosity (PIMs) exhibit unique structural properties, characterized by high surface area and rigid, twisted molecular configurations that hinder polymer chain stacking, resulting in micropores favorable for gas transport. PIM-1, a prominent member of this class, has been extensively explored for gas separation applications. However, its industrial use is limited by physical aging and low selectivity. To address these limitations, nitrile group functionalization in PIM-1, such as carboxyl group formation, has been investigated. In this study, we explore the hydrolysis of nitrile groups in PIM-1 under acidic conditions using pure methanesulfonic acid (MSA) and MSA/water mixtures. By systematically varying reaction parameters, we elucidate the transformation mechanism of nitriles to carboxylic acids. Results indicate that nitriles are effectively converted into the corresponding amides in pure MSA, while carboxylic acids (up to 80 %) in MSA/H₂O mixtures. Characterization techniques, including FTIR, ¹H NMR, UV–Vis spectroscopy, wide-angle X-ray diffraction (WAXD) and wide-angle X-ray scattering (WAXS), confirm the structural changes in the polymer and reveal contraction in interchain spacing due to hydrogen bonding. This study provides insights into optimizing the hydrolysis conditions for enhanced performance of PIM-based membranes in gas separation applications.

固有微孔聚合物（PIMs）具有独特的结构特性，其特点是高表面积和刚性，扭曲的分子构型阻碍聚合物链堆叠，从而形成有利于气体输送的微孔。PIM-1是该类中的一个突出成员，已被广泛地用于气体分离应用。然而，它的工业应用受到物理老化和低选择性的限制。为了解决这些限制，研究了PIM-1中的腈基功能化，例如羧基的形成。在这项研究中，我们探索了在酸性条件下，使用纯甲基磺酸（MSA）和MSA/水混合物水解PIM-1中的腈基。通过系统地改变反应参数，阐明了腈转化为羧酸的机理。结果表明，在纯MSA中，腈类化合物可以有效地转化为相应的酰胺类化合物，而在MSA/水混合物中，羧酸类化合物的转化率高达80%。表征技术，包括FTIR、1H NMR、UV-Vis光谱、广角x射线衍射（WAXD）和广角x射线散射（WAXS），证实了聚合物的结构变化，并揭示了氢键导致的链间间距收缩。该研究为优化水解条件以增强pim基膜在气体分离应用中的性能提供了见解。

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引用次数: 0

Preparation and application of high strength, high transparency, and high impact resistance polyurethane elastomers by controlled cross-linking 可控交联制备高强度、高透明度、高抗冲击聚氨酯弹性体及其应用

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.128002

Siqi Zhan, Hongyan Liu, Yanyan Bo, Ruize Yuan, Yuting Zhang, Dongxiu Zhang, Huimin Yang, Xin Tian, Shiwei Wang, Mingyao Zhang

In recent years, polyurethane elastomer has been widespread used in automotive, aerospace, and other fields depending on its wide range of adjustable properties, both high elasticity of rubber and plastic rigidity. Its high transparency and high strength have attracted increasing attention, especially in the application of laminated safety glass. In this work, an aliphatic polyurethane film with superior dynamic impact resistance, optical and mechanical properties were successfully obtained by controlling the cross-linking agent and cross-linking degree. The effects of different cross-linking point structures on the structure and properties of aliphatic polyurethane were revealed. The optimal bonding strength and tensile strength can reach 1.7 MPa and 43 MPa, which are 170 % and 301 % higher than those of polyurethane, respectively. The transmittance of the aliphatic polyurethane can reach 80 %. Extremely superior impact resistance of the laminated safety glass based on the aliphatic polyurethane have been verified. The ultimate bearing capacity was 14 times of unmodified polyurethane. It will have huge application potential in the fields of aerospace, construction and automotive.

近年来，聚氨酯弹性体凭借其广泛的可调性能，橡胶的高弹性和塑料的刚性，在汽车、航空航天等领域得到了广泛的应用。它的高透明度和高强度越来越受到人们的关注，特别是在夹层安全玻璃中的应用。通过控制交联剂和交联度，成功制备了具有优异动态抗冲击性能、光学性能和机械性能的脂肪族聚氨酯薄膜。揭示了不同交联点结构对脂肪族聚氨酯结构和性能的影响。最佳粘接强度和抗拉强度可达1.7 MPa和43 MPa，分别比聚氨酯提高170%和301%。脂族聚氨酯的透光率可达80%。经验证，脂肪族聚氨酯夹层安全玻璃具有极好的抗冲击性。极限承载力是未改性聚氨酯的14倍。在航空航天、建筑、汽车等领域具有巨大的应用潜力。

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引用次数: 0

Molecular orientation and solvent affinity in electrospun fibers of miscible blends 电纺丝混纺纤维的分子取向和溶剂亲和性

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-01-22 DOI: 10.1016/j.polymer.2024.127976

Arnaud W. Laramée, Jiayi Chen, Mélanie Le Faou, Christian Pellerin

The detailed structural characterization of electrospun fibers is crucial for understanding their processing-structure-properties relationships and optimizing their preparation. While many advanced applications of electrospun fibers incorporate multiple components, our current knowledge is predominantly based on one-component fibers, raising questions about its applicability to more complex materials. In this work, we investigate electrospun fibers composed of miscible blends of polystyrene (PS) with poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) to identify the key factors that impact their structure. Confocal Raman microscopy is employed to quantify the molecular orientation of PS and PPO at the single fiber level. The results reveal that PPO is much more oriented than PS at all compositions, with a widening gap as the PPO content increases. This unexpected behavior for a miscible blend coincides with a broadening of the glass transition, attributed to increased composition fluctuations at higher PPO content. The results suggest that a difference in solvent affinity between the two polymers, where PPO is less solvated than PS, reduces the relaxation of PPO and promotes that of PS, especially at high PPO content. This work demonstrates that electrospun fibers of miscible blends do not behave as a mere average of the properties of their constituents. Instead, the relative polymer-solvent affinity emerges as a central factor shaping their molecular organization.

电纺丝纤维的详细结构表征对于了解其加工-结构-性能关系和优化其制备至关重要。虽然电纺丝纤维的许多先进应用包括多种成分，但我们目前的知识主要是基于单组分纤维，这就提出了其对更复杂材料的适用性的问题。在这项工作中，我们研究了聚苯乙烯（PS）与聚（2,6-二甲基-1,4-苯乙烯氧化物）（PPO）共混物组成的电纺丝纤维，以确定影响其结构的关键因素。利用共聚焦拉曼显微镜在单纤维水平上定量了PS和PPO的分子取向。结果表明，在所有组分中，PPO的取向性都比PS强，且差距随着PPO含量的增加而扩大。混相混合物的这种意想不到的行为与玻璃化转变的扩大相一致，这是由于PPO含量较高时成分波动增加所致。结果表明，两种聚合物之间的溶剂亲和力差异，其中PPO比PS溶剂化程度低，减少了PPO的弛豫，促进了PS的弛豫，特别是在PPO含量高时。这项工作表明，混相共混物的电纺丝纤维的行为并不仅仅是其成分性能的平均。相反，相对的聚合物-溶剂亲和性成为塑造其分子组织的中心因素。

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引用次数: 0