变频电机用聚酰亚胺薄膜电老化特性研究

为研究变频电机用耐电晕型聚酰亚胺材料耐局部放电老化机理,采用电导电流法分别测量了普通聚酰亚胺薄膜(100HN)和耐电晕型聚酰亚胺薄膜(100CR)电晕老化前、经10kV/mm、20kV/mm电晕强度8h老化后的电老化阈值。结果表明,2种薄膜的电老化阈值随电老化强度的增加而减小,且耐电晕型薄膜的电老化阈值始终高于普通膜的阈值;在2种薄膜的空间电荷限制电流区内,耐电晕型薄膜的电流增长率较大,说明其中含有更多的浅陷阱,测试结果与其170°C下退极化电流测试结果一致。这些浅陷阱有效调节了聚酰亚胺薄膜中电场的分布,改善其耐电晕性能。     

变频电机用纳米复合绝缘薄膜老化性能的评估

对聚酰亚胺/纳米TiO2薄膜进行了热老化和电晕老化性能评估。利用热重点斜法评估了纯PI薄膜的耐热老化性能,用TGA、DSC等手段研究了聚酰亚胺/纳米TiO2复合材料薄膜的相对耐热性能。基于IEC60343标准建立了一套耐电晕老化试验系统,对不同纳米填充量的聚酰亚胺/纳米TiO2复合薄膜进行了耐电晕老化试验。结果表明,纳米TiO2的引入,改善了聚酰亚胺薄膜的耐电晕性能,提高了聚酰亚胺薄膜在变频绝缘的运行寿命,但是随着纳米TiO2填充量的进一步增加,薄膜的耐电晕寿命以及热性能下降。     

耐电晕聚酰亚胺薄膜研究进展

聚酰亚胺因其耐电晕性能不足严重缩短了复杂工况下的使用寿命，纳米改性技术的应用为耐电晕聚酰亚胺薄膜的研发提供了新的发展方向。该文首先从耐电晕机理出发，综述了电晕下聚酰亚胺的老化进程；然后从材料的介电特性、电导特性、陷阱特性、界面效应及热导率等性能参数分析了提升复合聚酰亚胺耐电晕性能的策略；最后针对当前耐电晕聚酰亚胺薄膜研究存在的问题进行了总结，并对未来发展方向做出了展望，以期实现具有优异耐电晕性能聚酰亚胺薄膜的研发。     

风力发电机用云母带和复合材料高频电老化性能研究

本文对复合材料在不同影响因素下进行高频电老化试验研究,探讨不同影响因素对高频电老化寿命的影响;并对不同风电用云母带及复合材料在重复脉电压下进行电老化寿命评估。结果表明:高频电老化寿命受不同因素的影响较大;相同试验条件下,耐电晕聚酰亚胺薄膜少胶粉云母带、聚酰亚胺薄膜少胶粉云母带、聚酯薄膜少胶粉云母带的耐高频电老化寿命顺序降低,复合材料浸胶NHN、浸胶NMN、浸胶TFT、NHN、NMN、TFT的耐高频电老化寿命也顺序降低。     

YQ200牵引电机定子线圈绝缘结构的电性能分析

通过对YQ200牵引电机定子线圈常规电性能及其高频脉冲电老化性能的研究,结果表明:YQ200定子线圈的常规电性能远远优于相关标准值,采用杜邦耐电晕聚酰亚胺薄膜结构的电磁线高频脉冲的耐老化时间远高于普通薄膜烧结线.     

正电性纳米层状材料对聚酰亚胺电性能的影响

二维纳米层状材料是改善聚合物电性能的重要填料。以对氨基苯甲酸为插层剂,利用离子交换制备了有机插层水滑石。以插层水滑石为纳米填料,通过原位聚合制备了水滑石/聚酰亚胺复合薄膜材料,研究具有正电性的水滑石层状材料对聚酰亚胺薄膜耐电晕性能的影响。结果表明:层板间的对氨基苯甲酸与聚合物的键合作用以及层板间聚合物分子链的增长,促进了水滑石在聚合物基体中的剥离分散;剥离后形成具有正电性的层状纳米片对复合材料的不同性能呈现不同的影响规律;层状纳米片能够提高复合薄膜的电气强度(增加了11%)和耐电晕时间(增加了4.7倍),同时能够增强和增韧复合材料。     

氟化时间对聚酰亚胺薄膜空间电荷分布的影响

聚酰亚胺薄膜作为一种综合性能优异的绝缘材料,被广泛应用于超导电缆等电气电子设备。然而,薄膜积累的空间电荷会引发电场畸变,进而影响材料的老化、极化、击穿等特性。已有研究表明表面氟化能改变聚酰亚胺表层结构,从而影响电荷注入和积累。为探究氟化对聚酰亚胺薄膜空间电荷分布的影响,使用热脉冲法(TSM)研究了氟化时间为0、15、30、45和60 min且厚度为25μm的纯、耐电晕和双层纯聚酰亚胺薄膜试样的空间电荷分布现象。研究结果表明:对于纯聚酰亚胺薄膜试样,氟化时间为45 min时空间电荷积聚最少;对于耐电晕聚酰亚胺薄膜试样,空间电荷在纳米粒子与氟化层的双重作用下随着氟化时间的增长而逐渐减少;同样氟化时间的纯聚酰亚胺薄膜试样与耐电晕聚酰亚胺薄膜试样相比,耐电晕聚酰亚胺薄膜试样的空间电荷积累更少;对于双层纯聚酰亚胺薄膜试样,界面两侧薄膜的表面特性差别对空间电荷积聚有重要影响,且可有效屏蔽电子的注入。由此可得结论:空间电荷分布与积累情况随氟化时间不同而不同,适当的氟化程度能有效抑制空间电荷积累并提高超导电缆绝缘性能。     

聚酰亚胺基BN微纳米复合材料的电气绝缘性能研究

通过原位聚合法制备了不同BN掺杂含量的聚酰亚胺基微纳米复合材料,使用扫描电镜、偏光显微镜、电气强度测试仪、介损及介电常数测量系统、皮安表和耐电晕老化实验装置对不同掺杂含量的微纳米复合PI薄膜的结构和电性能及耐电晕老化性能进行了研究。结果表明:随着BN微纳米颗粒掺杂量的增加,复合PI薄膜的电气强度先增大后减小,当掺杂含量为1%时,交流电气强度达到最大值219.6 kV/mm。掺杂BN后,复合PI薄膜的介电常数和介质损耗都有所增加,在高温下的电导电流小于纯PI薄膜。随着BN掺杂量的增加,复合PI薄膜的耐电晕老化性能逐步提升,在掺杂含量为20%时,复合PI薄膜的耐电晕老化时间是纯PI薄膜的116.7倍。     

无机纳米杂化聚酰亚胺薄膜的研究进展

无机纳米杂化聚酰亚胺复合薄膜因无机填料在聚合物基体中纳米尺度的分散以及与基体间强的化学结合而具有较常规聚酰亚胺薄膜材料更优异的力学性能、热稳定性能、高绝缘性能及耐电晕性能等.依据国内外聚酰亚胺纳米杂化薄膜材料的最新研究情况,重点综述了SiO2/Al2O3、SiO2/Ti2O3、SiO2、TiO2、Al2O3、SiC、MMT等纳米杂化聚酰亚胺薄膜的研究进展,表明其是一种性能优异、具有广泛应用前途的有机一无机纳米复合材料,但尚存在许多需进一步深入研究的问题.     

几种绝缘结构和绝缘材料的高频耐电晕性能分析

研究了几种绝缘材料和绝缘结构的电性能,利用高频脉冲绝缘测试仪器分析比较了其耐电晕性能。结果表明:杜邦耐电晕聚酰亚胺薄膜的耐电晕性能优于国产聚酰亚胺薄膜,耐电晕聚酰亚胺薄膜绝缘结构具有较好的耐电晕性能。     

Application of aramid film to electrical and electronic uses inJapan

The p-aromatic polyamide (aramid) films have recently been developed in Japan and have attracted attention as a promising new material because of their combination of an outstandingly high Young's modulus and their excellent heat resistance. Because they are a new addition to the family of electrical insulating materials, their background, chemical structure, and film-forming method, along with their characteristics, including general, mechanical, electrical, thermal, and chemical properties, have been outlined. A new application as a cassette tape for a DAT has been described. The article has attempted to contrast the new aramid films with the older polyimide and PET films. In particular, the author's study of the hydrophilic nature of aramids in contrast with polyimide films has been reviewed. The success in miniaturizing cassette tape for the DAT indicates that these films may be applicable to other electrical/electronic uses. Surely other uses will be found for a material with such outstanding properties as aramid film     

纳米硅/铝氧化物杂化聚酰亚胺薄膜电性能研究

为了提高聚酰亚胺薄膜的电学性能,将纳米硅/铝氧化物掺杂到聚酰亚胺(PI)基体中,通过固定掺杂总量,调整纳米硅/铝氧化物的相对质量百分含量,制备出一系列的无机纳米杂化聚酰亚胺薄膜。采用SEM(扫描电镜)表征了薄膜的表面形貌,对薄膜电气强度和耐电晕寿命进行了测试。结果表明:无机纳米杂化聚酰亚胺薄膜与纯的聚酰亚胺薄膜相比其电性能大幅度提高。     

聚酰亚胺/氧化硅/氧化铝纳米杂化薄膜的制备及结构与性能研究

用溶胶-凝胶法制备了纳米氧化硅(SiO2)及纳米氧化铝(Al2O3)溶胶,并将二者掺入到聚酰胺酸基体中,亚胺化得到聚酰亚胺(PI)/SiO2/Al2O3杂化薄膜,采用红外光谱、原子力显微镜、热失重及阻抗分析仪对薄膜的结构及热性能、介电性能进行表征。结果表明,SiO2和Al2O3粒子呈纳米级均匀分散在薄膜基体中,并且与有机相存在键合;材料的热分解温度有所提高;介电常数随无机含量的增加而增加。     

Interfacial electrostatic phenomena and capacitance–voltage characteristics of ultrathin polyimide Langmuir–Blodgett films

Capacitance–voltage (C–V) characteristic of ultrathin polyimide (PI) Langmuir–Blodgett (LB) films is discussed theoretically and experimentally taking into account the interfacial electrostatic phenomena and interfacial electronic states at the metal/PI LB film interface. It was found that the apparent film thickness decreases due to the charge exchange phenomena at the metal/film interface. It was also found that electrical insulating properties of the Au/PI LB film/Al device depended on the polarity of external voltage, probably due to the formation of the electrostatic interfacial electric field of 10⁸ to 10⁹ V/m. © 2000 Scripta Technica, Electr Eng Jpn 134(3): 9–15, 2001     

聚酰亚胺／蒙脱土纳米复合薄膜的制备和性能研究

本文以均苯四甲酸二酐（PMDA）和4,4’－二氨基二苯醚（DAPE）作主要原料合成的聚酰亚胺（PI）为基体,以有机化蒙脱土（MMT）为无机相,制备了聚酰亚胺／MMT纳米复合薄膜,采用透射电镜（TEM）,X射线衍射（XRD）对薄膜微相形态结构进行了分析测试,考察了薄膜的拉伸强度,电气性能和热性能。     

聚酰亚胺/纳米氧化铝复合薄膜的研究

采用溶胶-凝胶法制备了聚酰亚胺／A1203,纳米复合薄膜,通过测定胶液在贮存过程中粘度的变化研究了纳米复合胶液的贮存稳定性,采用热失重分析、拉伸强度和体积电阻率等测试方法研究了纳米复合薄膜的性能。结果表明,当A1K）,含量不大于14％时,纳米Alz03前驱体的存在对纳米复合胶液的贮存稳定性影响不大或基本上没有影响;与纯PI薄膜相比,Ah03含量不大于5％时,纳米复合薄膜的表观分解温度、拉伸强度以及常态下的体积电阻率均有明显提高：纳米A120,的存在有利于改善高温电性能。     

A new polyimide film for VLSI and its electrical characterization

Multilevel structures consisting of alternating metal and dielectric layers are necessary to achieve interconnection in high density or VLSI (very large scale integration) circuits using either MOS or bipolar technology. Polyimide is one of the excellent high temperature heat-resistant polymers in organic materials and has good planarization capability and electrical insulating properties. In this work, following the synthesis of DAPDS (4,4'-bis (3-aminophenoxy)diphenyl sulfone), by nucleophilic aromatic substitution of 4,4'-dichlorodiphenyl sulfone with m-aminophenol, DAPDS/pyromellitic dianhydride based soluble and processable fully imidized polyimide was synthesized successfully by using solution imidization technique. Using this specific polyimide, a metal-polyimide-silicon MIS (metal polyimide silicon) structure was manufactured. Electrical properties of the MIS capacitance have been examined. The planarizing and patterning characteristics and electrical characteristics such as current vs. voltage, breakdown field strength, permittivity and capacitance vs. voltage for quasi-static and high frequency measurements are discussed. The results are compared with conventional dielectric films used in integrated circuit fabrication     

Effects of sputtering pressure and thickness on properties of ZnO:Al films deposited on polymer substrates

Highly conducting and transparent aluminum doped zinc oxide (ZnO:Al) thin films have been deposited on polyimide substrate by r.f. magnetron sputtering at room temperature. The influence of sputter pressure and thickness on the structural, electrical, and optical properties of ZnO:Al films deposited on polyimide substrate is reported. The crystallinity and degree of orientation was increased by decreasing the sputter pressure. For higher sputtering pressures an increase on the resistivity was observed due to a decrease on the mobility and the carrier concentration. As the film thickness was increased, the crystallite sizes were increased, but the average transmittance in the wavelength range of the visible spectrum was decreased. The electrical performances of the ZnO:Al films deposited on glass substrates are slightly worse than the ones of the films deposited on polyimide substrates with same thickness. The lowest resistivity of 8.6?×?10^?4 Ω cm can be obtained for films deposited on glass substrate with the thickness of 800 nm.     

3种聚合物薄膜拉伸状态下的绝缘强度研究

研究了聚四氟乙烯(PTFE)、聚酰亚胺薄膜(PI)、聚丙烯层压纸(PPLP)3种聚合物薄膜经液氮浸泡和冷热循环后在拉伸状态下的电气绝缘强度,并与未处理的样品进行对比。结果表明:未处理时,PI薄膜的工频绝缘强度最大;经液氮浸泡后,PTFE和PI薄膜的工频绝缘强度相当,而PPLP薄膜的工频绝缘强度相对稳定。     

电子束辐照对聚酰亚胺电气性能的影响

研究了高能电子束辐照对聚酰亚胺薄膜(PI)试样电气性能的影响。实验发现高能电子束辐照后PI的介电常数减小,电导率增大,电损耗增大。利用原位聚合法把70纳米Al2O3粒子引入到PI薄膜中,对材料进行改性,实验发现改性后PI薄膜抗高能电子束辐射能力得到加强。