共查询到19条相似文献,搜索用时 93 毫秒
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聚酰亚胺薄膜/玻璃布复合物的研究 总被引:2,自引:0,他引:2
聚酰亚胺薄膜是一种性能优良的绝缘材料,通常被用作电机槽绝缘,本文所报导的聚酰亚胺薄膜/玻璃布复合材料具有与聚酰亚胺薄膜相同的热稳定性,且拉伸强度优于聚酰亚胺薄膜,文中着重讨论了复合材料中玻璃布的影响。 相似文献
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以前曾指出(1~5),单轴定向显著地改善了聚酰亚胺薄膜的性能。但是已发表的数据仅是片断的并且是以实验室试验结果为基础的。研究聚酰亚胺薄膜的性能与定向工艺条件的关系以及研究定向薄膜的物理机械特性,引起了人们的注意。作为研究对象,采用了厚度40微米的ΠM型工业聚酰亚胺薄膜。在连续单向定向 相似文献
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聚酰亚胺以其优良的电气性能作为一种重要的绝缘介质在工业领域得到了广泛的应用。由于温度能够显著影响绝缘介质的老化程度,对不同温度条件下聚酰亚胺薄膜的空间电荷分布开展研究具有重要的意义。最近的研究表明,表面氟化技术能够在不破坏聚酰亚胺薄膜内部分子结构的前提下改变其表层分子结构从而进一步提高其电气性能。通过对聚酰亚胺进行不同条件下改性处理,制备了4组试验试样,每组样品为两层聚酰亚胺叠加以研究其界面空间电荷分布。所用试样表面氟化处理时间分别为15 min、45 min和75 min。搭建了基于激光热脉冲法的空间电荷测量装置,分别测量了40℃、80℃、120℃、160℃下试样的空间电荷分布。结果表明表面氟化处理技术能够调节聚酰亚胺薄膜间空间电荷分布,且随着温度的提高聚酰亚胺内部积聚的空间电荷变少。 相似文献
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大气压微等离子体射流对聚酰亚胺薄膜的表面改性 总被引:8,自引:8,他引:0
聚酰亚胺具有良好的机械性能、耐热性能和耐低温性能,因而具有广泛的应用。为提高聚酰亚胺薄膜材料的表面性能,利用自行设计的大气压Ar微等离子体射流对聚酰亚胺薄膜材料进行了表面改性实验。实验研究了Ar微等离子体射流对聚酰亚胺薄膜材料的亲水性和表面能随处理时间的变化规律。测量了处理后的聚酰亚胺薄膜材料在空气中放置时的处理效果的变化情况。研究结果表明,随着处理时间的增加,聚酰亚胺薄膜的水接触角逐渐降低,而表面能逐渐增加,并且处理后的材料在空气中放置时会出现老化效应。采用原子力显微镜观察了改性前后的表面形貌,发现处理后的聚酰亚胺薄膜的表面更加粗糙,同时质量也有所减少。 相似文献
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聚酰亚胺薄膜是一种性能优异的绝缘材料,通常被用作电机槽绝缘。本文所报导的聚酰亚胺薄膜/玻璃布复合材料具有与聚酰亚胺薄膜相同的热稳定性,且拉伸强度优于聚酸亚胺薄膜。文中着重讨论了复合材料中玻璃布的影响。 相似文献
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测量了聚酰亚胺薄膜在冷热循环过程中各温度点的热膨胀系数。结果表明:聚酰亚胺薄膜的热膨胀系数具有不稳定性,当经四次冷热循环后才趋于稳定 相似文献
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The development of polyimide films in Japan is discussed. The chemical structure of the films and their polymerization mechanisms are described. Types of polyimide films are identified, and their characteristics are examined. Special attention is given to their thermal and chemical properties and their radiation resistance. Applications of polyimide films to rotating machines, integrated circuits, tape-automated bonding, flexible printed-circuit boards, electric wires, aerospace and nuclear equipment, and recording devices are discussed 相似文献
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本文为探究在方波脉冲下聚酰亚胺(polyimide,PI)/纳米复合薄膜的耐电晕特性,采用原位聚合法制备了纯膜和掺杂纳米氧化铝的复合薄膜,通过傅里叶红外光谱(FTIR)技术分析了薄膜的化学结构,测量了纯膜和纳米膜的表面电阻率,并在重复方波脉冲下进行耐电晕实验,最后运用扫描电子显微镜(SEM)分析电晕击穿前后薄膜的微观形态。实验结果表明:纯膜和纳米膜的耐电晕时间都会随着电压的升高而降低,并且在同一电压下,纳米膜的耐电晕特性优于纯膜。通过测试分析,从纳米粒子和聚合物基体间形成的界面、薄膜表面电荷分布、薄膜试样击穿过程3个方面对纳米薄膜优异的耐电晕特性给出了解释。 相似文献
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Jae-Hyeong Lee 《Journal of Electroceramics》2009,23(2-4):512-518
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. 相似文献
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连续方波脉冲电压下温度对聚酰亚胺薄膜局部放电特性的影响 总被引:1,自引:0,他引:1
为了评估温度对局部放电(partial discharge,PD)特性的影响,对连续方波脉冲电压条件下的局部放电测试系统进行了改进,并采用该系统测试变频电机用聚酰亚胺纳米复合薄膜在不同温度条件下的局部放电特性,分析了不同温度下的局部放电散点图、放电次数及绝缘寿命。试验结果表明:局部放电多集中在方波脉冲的上升沿及下降沿附近,且在电压负半周期平顶区内,出现了大量放电;同时,随着实验温度的增加,局部放电次数及放电幅值虽然降低,但聚酰亚胺的绝缘寿命也逐渐降低,这说明局部放电只是引起聚酰亚胺纳米复合薄膜绝缘失效的原因之一,高温条件下活性电子的入陷、脱陷过程及空间电荷造成的电场畸变可能是诱导绝缘失效的另一个因素。 相似文献
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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 相似文献
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A. V. Papkov N. I. Berezinets A. V. Kireev V. M. Pak 《Russian Electrical Engineering》2011,82(4):189-191
Class-H insulation systems (180°C) of traction electric motors based on polyimide and polyethylene naphthalate films are presented.
The methods and the key results of the longevity tests of different insulation systems are presented. 相似文献