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气体类型对正极性重复方波电压下PEEK沿面放电特性的影响

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高电压技术 2023年第12期49卷 5260-5269页

作者：裘朱钢李学宝李叶赵志斌华北电力大学新能源电力系统全国重点实验室北京102206

为研究不同气体对电力电子器件绝缘材料沿面放电特性的影响,分别测量了SF6、N_(2)和空气中正极性重复方波电压下聚醚醚酮(polyetheretherketone,PEEK)的沿面放电电流脉冲,详细分析了3种气体中PEEK的沿面放电起始电压(partial discharge ... 详细信息

为研究不同气体对电力电子器件绝缘材料沿面放电特性的影响,分别测量了SF6、N_(2)和空气中正极性重复方波电压下聚醚醚酮(polyetheretherketone,PEEK)的沿面放电电流脉冲,详细分析了3种气体中PEEK的沿面放电起始电压(partial discharge initial voltage,PDIV)、放电电流脉冲波形参数以及放电平均时间延迟。测量结果表明,在相同条件下,SF6中PEEK沿面放电起始电压最高,N_(2)中次之,空气中最低;SF6中放电电流脉冲的幅值远小于N_(2)和空气的值,且正向放电脉冲幅值略小于反向放电脉冲幅值,N_(2)和空气中正向放电脉冲幅值大于反向放电脉冲幅值,且N_(2)中两者的差值更大;SF6中放电平均时间延迟最大,N_(2)中次之,空气中最小,SF6中反向放电时间延迟大于正向放电时间延迟,反向放电的加速因子大于正向放电的加速因子;N_(2)和空气中反向放电时间延迟小于正向放电时间延迟,反向放电的加速因子小于正向放电的加速因子。在已有研究的基础上提出PEEK在SF6中的沿面放电模型,对比不同类型气体下的放电特性差异,解释SF6气体环境中PEEK的沿面放电机制。

关键词：正极性重复方波电压 PEEK 沿面放电 SF6 时间延迟

Tribological and mechanical behaviours of resin-based friction materials based on microcrack filling

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Biosurface and Biotribology 2023年第1期9卷 1-8页

作者： Lekai Li Guixiong Gao Jin Tong Jian Zhuang Wei Song Yunhai Ma Guoqin Liu Feipeng Cao Shengwang Yuan Qifeng Zhang Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchunChina

To enhance the friction performance of resin-based friction materials,five types of specimens with different polymer ether ketone(PEEK)contents were fabricated and their physiomechanical behaviours were tested and,their tribological properties were investigated using a JF150F-II constant-speed tester.It was found that the addition of PEEK had a positive influence on the properties of the friction materials,and sample FM-3(the shorthand of‘Friction Materials-3’,containing 2 wt%PEEK)exhibited improved friction performance with a fade ratio and recovery ratio of 8.6%and 101.1%respectively.Among all samples,FM-4(the shorthand of‘Friction Materials-4’,con-taining 3 wt%PEEK)had the lowest specific wear rate with a value of 0.622×10^(−7)cm^(3)(N⋅m)^(−1)at 350℃.The PEEK can fill the microcracks in the composite at a high tem-perature and can also cover the hard abrasive particles to prevent them from directly damaging the composite.The findings from this study afford a foundation for studies to further improve the properties of resin-based friction materials.

关键词： fade ratios friction materials PEEK recovery ratios specific wear rate

Robust and High-Wettability Pristine Poly(ether ether ketone) Nanofiber Separator for Heat-Resistant and Safe Lithium-Ion Battery

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Chinese Journal of Polymer Science 2023年第12期41卷 1937-1946,I0009页

作者： Xin-Ke Dai Feng-Shan Yu Jia-Wei Wen Chun-Xia Wang Xin-Long Ma Wang Yang Guo-Yong Huang Hai-Mu Ye College of New Energy and Materials China University of PetroleumBeijing 102249China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

Separator is a pivotal component of lithium-ion batteries(LIBs)and determines the electrochemical performance and safety.However,with the increase in energy density and application scenarios,commercial polyolefin separators are increasingly unable to undertake heavy responsibility of battery safety protection.Herein,a new kind of nanofiber separator based on poly(ether ether ketone)(PEEK)with excellent thermal stability,self-extinguishing,and superior electrochemical properties is reported.Effective inheritance of intrinsic properties from raw PEEK materials and optimized hot-pressing operation endows the separator with high robustness and wettability,showing tensile strength of 15.8 MPa and a contact angle of 17.2°.The high thermal stability of PEEK can ensure the separator to preserve the structural integrity and microstructure at temperatures beyond 300℃,and the excellent self-extinguishing peculiarity of PEEK capacitates the high safety of LIB.Notably,benefitting from high porosity and polar surface,the PEEK separator shows high electrolyte uptake of 245.5%and exhibits a wider electrochemical window and faster lithium-ion transport number than commercial polyolefin separators.Furthermore,cells assembled with PEEK separator display better performance than the ones with PE separator,and the PEEK LIB has been successfully used to light up a lamp at a high temperature of 150℃.

关键词： Separator Lithium-ion battery Heat-resistance PEEK

The influence of lubricant temperature on the wear of total knee replacements

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Biosurface and Biotribology 2023年第3期9卷 71-77页

作者： Raelene M.Cowie Adam Briscoe Louise M.Jennings Institute of Medical and Biological Engineering University of LeedsLeedsUK Invibio Ltd.Thornton Cleveleys LancashireUK

Experimental in vitro simulation can be used to predict the wear performance of total knee replacements.The in vitro simulation should aim to replicate the in vivo loading,motion and environment experienced by the joint,predicting wear and potential failure whilst minimising test artefacts.Experimental wear simulation can be sensitive to envi-ronmental conditions;the environment temperature is one variable which should be controlled and was the focus of this investigation.In this study,the wear of an all‐polymer(PEEK‐OPTIMA™polymer‐on‐UHMWPE)total knee replacement and a conventional cobalt chrome‐on‐UHMWPE implant of similar initial surface topography and geometry were investigated under elevated temperature conditions.The wear was compared to a previous study of the same implants under simulator running temperature(i.***.without heating the test environment).Under elevated temperature conditions,the wear rate of the UHMWPE tibial inserts was low against both femoral component materials(mean<2 mm3/million cycles)and significantly lower(p<0.05)than for investigations at simulator running temperature.Protein precipitation from the lubricant onto the component articulating surfaces is a possible explanation for the lower wear.This study highlights the need to understand the influence of different variables including envi-ronmental temperature to minimise the test artefacts during wear simulation which may affect the wear rates.

关键词： biotribology PEEK total knee replacement UHMWPE wear

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注塑发泡工艺对PEEK制品性能影响

塑料 2024年第3期53卷 93-98页

作者：马艺涛李景朱宁迪陆蕾键杨卫民谢鹏程北京化工大学机电工程学院北京100029 海天塑机集团有限公司浙江宁波315821 北京化工大学有机无机复合材料国家重点实验室北京100029 北京化工大学人工智能交叉研究中心北京100029

聚醚醚酮(PEEK)作为最具代表性的特种工程塑料,由于其具有较好的力学性能已被广泛应用于航天和军事领域。采用超临界流体注塑发泡的方式制备了发泡聚醚醚酮,发泡制品的质量降低了21%(比强度为59.8),最低介电常数为2.47。泡孔结构的介入... 详细信息

聚醚醚酮(PEEK)作为最具代表性的特种工程塑料,由于其具有较好的力学性能已被广泛应用于航天和军事领域。采用超临界流体注塑发泡的方式制备了发泡聚醚醚酮,发泡制品的质量降低了21%(比强度为59.8),最低介电常数为2.47。泡孔结构的介入降低了制品的力学性能,但是,较好的减重效果使发泡制品仍然具有较好的比强度。探究了泡孔结构对发泡PEEK制品的介电性能的影响规律,结果表明,更宽的发泡层使样品中的气体含量更高,可以有效降低制品的介电常数。由于分子链的极化作用,PEEK试样在X波段存在明显的介电常数波动现象。结晶可以抑制分子链的极化,因此,较高的结晶度可以降低制品的介电常数。研究表明,定向调控PEEK发泡制品的介电性能提供了指导方向。

关键词：注塑发泡 PEEK 介电性能轻量化力学性能

Solvent-resistant porous membranes using poly(ether−ether ketone): preparation and application

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Frontiers of Chemical Science and Engineering 2022年第11期16卷 1536-1559页

作者： Lixin Xing Jiaming Wang Xuehua Ruan Gaohong He State Key Laboratory of Fine Chemicals R&D Center of Membrane Science and TechnologySchool of Chemical EngineeringDalian University of TechnologyDalian 116023China School of Chemical Engineering at Panjin Campus Dalian University of TechnologyPanjin 124221China

Poly(ether−ether ketone)(PEEK)is a linear aromatic macromolecule,which can form semi-crystalline aggregative status,allowing PEEK materials to have strong environment tolerance and excellent physicochemical properties.PEEK materials have become a promising alternative to fabricate particular membranes used in extreme conditions.In the past few decades,many researches and evolutions have emerged in membrane fabrication with PEEK materials and its applications for treating organic solvents and their mixtures;however,there are little systematic and comprehensive literature to summarize fabrication approaches,compile applications,and elaborate PEEK property-structure relationship.In this review,the main approaches to fabricate PEEK-based membranes are illustrated concretely,including conventional thermal-induced and non-solvent-induced phase separation,and novel chemical-induced crystallization;the representative applications in ultrafiltration,nanofiltration and membrane contactor containing organic solvents are demonstrated systematically.Meanwhile,the mechanism to tune PEEK solubility in solvents,which can be achieved by altering monomers in synthesis processes or changing membrane preparation routes,is deeply analyzed.Moreover,the existing problems and the future prospects are also discussed.This review provides positive guidance for designing and fabricating membranes using PEEK and its derivative materials for task-specific applications in harsh conditions.

关键词： PEEK phase inversion solvent-resistant membrane nanofiltration membrane contactor

Small extracellular vesicles with nanomorphology memory promote osteogenesis

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Bioactive Materials 2022年第11期7卷 425-438页

作者： Liang Ma Wencan Ke Zhiwei Liao Xiaobo Feng Jie Lei Kun Wang Bingjin Wang Gaocai Li Rongjin Luo Yunsong Shi Weifeng Zhang Yu Song Weibin Sheng Cao Yang Department of Orthopaedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Department of Spine Surgery The First Affiliated Hospital of Xinjiang Medical UniversityUrumqi830054China

Nanotopographical cues endow biomaterials the ability to guide cell adhesion, proliferation, and differentiation. Cellular mechanical memory can maintain the cell status by retaining cellular information obtained from past mechanical microenvironments. Here, we propose a new concept “morphology memory of small extracellular vesicles (sEV)” for bone regeneration. We performed nanotopography on titanium plates through alkali and heat (Ti8) treatment to promote human mesenchymal stem cell (hMSC) differentiation. Next, we extracted the sEVs from the hMSC, which were cultured on the nanotopographical Ti plates for 21 days (Ti8-21-sEV). We demonstrated that Ti8-21-sEV had superior pro-osteogenesis ability in vitro and in vivo. RNA sequencing further confirmed that Ti8-21-sEV promote bone regeneration through osteogenic-related pathways, including the PI3K-AKT signaling pathway, MAPK signaling pathway, focal adhesion, and extracellular matrix-receptor interaction. Finally, we decorated the Ti8-21-sEV on a 3D printed porous polyetheretherketone scaffold. The femoral condyle defect model of rabbits was used to demonstrate that Ti8-21-sEV had the best bone ingrowth. In summary, our study demonstrated that the Ti8-21-sEV have memory function by copying the pro-osteogenesis information from the nanotopography. We expect that our study will encourage the discovery of other sEV with morphology memory for tissue regeneration.

关键词： Nanotopographic PEEK hMSCs Small extracellular vesicles Osteogenesis

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PEEK复合材料在滑动轴承中的应用

轴承 2023年

作者：禹程洪朱杰张亚宾黄帅冯凯湖南大学国家高效磨削工程技术研究中心湖南崇德科技股份有限公司湖南大学高端智能装备关键部件湖南省重点实验室

滑动轴承径向尺寸小、承载能力强，广泛应用于工程机械、海洋设备、航空航天等领域。PEEK耐磨性、化学稳定性及尺寸稳定性优良，是一种具有高强度的滑动轴承用自润滑材料。纯PEEK在应用中存在表面粘结性待加强、耐磨性难达到工程要求等... 详细信息

滑动轴承径向尺寸小、承载能力强，广泛应用于工程机械、海洋设备、航空航天等领域。PEEK耐磨性、化学稳定性及尺寸稳定性优良，是一种具有高强度的滑动轴承用自润滑材料。纯PEEK在应用中存在表面粘结性待加强、耐磨性难达到工程要求等不足，需改性处理获得性能更优异的PEEK复合材料，以满足滑动轴承在复杂工况下的综合性能要求。本文围绕PEEK复合材料在滑动轴承中的应用展开，对PEEK材料特性及常用改性方法、PEEK复合材料摩擦磨损特性、加工成型方法，复合材料与金属基底结合方式等进行了综述。结合PEEK复合材料在压缩机、水泵、磁力泵、高温机械等设备中的应用分析了PEEK滑动轴承的优势，并探讨了PEEK复合材料在滑动轴承中的应用前景，以期为新型PEEK复合材料滑动轴承的设计与研发提供参考。

关键词： PEEK 滑动轴承摩擦磨损加工成型结合方式

精密轴承用PEEK注塑保持架结构及加工工艺优化

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轴承 2023年

作者：董胤喆宁仲李建星孙小波席博伦河南省高性能轴承技术重点实验室洛阳轴承研究所有限公司

通过对精密轴承用PEEK注塑保持架结构设计、模具设计、注塑工艺等方面的研究，提出保持架精度的提升措施。对PEEK保持架的性能指标进行检测：保持架外径圆度在0.15 mm以内(含0.15 mm)占比86%；保持架环状拉伸强度平均值97.82 MPa；200... 详细信息

通过对精密轴承用PEEK注塑保持架结构设计、模具设计、注塑工艺等方面的研究，提出保持架精度的提升措施。对PEEK保持架的性能指标进行检测：保持架外径圆度在0.15 mm以内(含0.15 mm)占比86%；保持架环状拉伸强度平均值97.82 MPa；200℃高温摩擦系数平均值为0.195，磨痕宽度平均值为0.9625mm，磨损量平均值为0.1394mm3；保持架装配的轴承满足P4级精密轴承旋转精度的要求；轴承振动值≤37dB，达到Z4等级要求。

关键词： PEEK 保持架模具仿真分析注塑工艺