聚苯硫醚（PPS）薄膜

本文介绍了新型F级聚苯硫醚(PPS)薄膜的发展,性能,制造和用途。PPS薄膜同聚对苯二甲酸乙二酯薄膜相比,具有耐热,难燃,耐潮和耐水解的优点,同聚酰亚胺薄膜相比,具有成本低,原料丰富易得的优点,并且可以利用现有设备加工薄膜。     

聚苯硫醚喷塑工艺的研究

前言 湘潭电机集团特电分公司公司承制的一项重要开关装备,上有一根主轴,为防止开关上的部件通过主轴产生短路现象,要求该轴表面必须绝缘,开关系统工作电压为1000V,为确保系统安全,表面绝缘必须能耐3000V的高压。该轴上     

一种新型聚苯硫醚树脂—Fortron^TMPPS

文章介绍了一类新型热塑性树脂,它是美国色兰尼斯工程树脂公司在聚苯硫醚的基础上开发出来并以Ｆｏｒｔｒｏｎ商标投放市场的新材料。文章对这类产品的几个关键特性,如低离子含量,良好的相对韧性等进行了阐述。     

聚苯硫醚低介电改性的研究进展

本文综述了聚苯硫醚低介电改性的研究进展,包括采用玻纤增强、无机粒子填充、聚合物共混、引入空气微孔等方式改性聚苯硫醚,旨在保持聚苯硫醚优良综合性能的同时降低其介电常数和介质损耗,以期为其他热塑性工程塑料的低介电改性研究提供参考。     

关于薄膜偏厚问题原因分析

1999年上半年 ,我公司的薄膜在部分用户使用过程中 ,发现有部分薄膜厚度偏厚的现象 ,导致部分卷绕的电容器芯子装不进外壳。我公司广大工程技术人员经几个月 ,多次走访用户并进行认真、细致、深入的调查 ,并抽取大量试样重新测试 ,薄膜厚度均在我公司内控厚度偏差范围 ,应属合格产品。后经研究分析 ,我们认为 1 999年上半年部分用户反映我公司薄膜偏厚主要有以下几个方面的原因。1　测试方法不统一GB/T1 2 80 2 - 1 996《电容器用聚丙烯薄膜》国家标准中第 5 .3条规定薄膜厚度试验方法按 GB/T1 35 41 - 1 992《电气用塑料薄膜试验方法》…     

双轴拉伸聚丙烯薄膜内皱的原因分析

本文从接触辊直径和工艺参数两个方面分析了ＢＯＰＰ薄膜分切重卷中产生内皱的原因，并以此为依据采取相应措施来解决膜卷内皱问题。     

等离子体聚合乙烯薄膜的制备及其电击穿的初步研究

利用射频放电的低温等离子体对乙烯气体进行气相聚合，得到了均匀无针孔的等离子体聚乙烯薄膜，对化学结构进行了对比研究，对其电击穿特性进行了初步讨论。     

小波分析方法在磁光记录薄膜基本特性分析中的应用

利用小波分析方法取代传统的傅立叶方法对微弱的磁光记录薄膜信号进行分解、滤波和局部信号处理,大大提高了测量的灵敏度,更好地分析了磁光记录薄膜的基本特性。     

Dielectric properties of poly(phenylene sulfide) as a function of temperature and frequency

Dielectric properties of poly(phenylene sulfide) (PPS), a kind of super engineering plastic, were investigated over a wide temperature range by measuring its frequency spectra of complex permittivity and thermally stimulated polarization and depolarization currents (TSPC and TSDC). Experimental results indicate that its permittivity and dielectric loss factor remain stable and maintain low values up to around 140 °C, despite the fact that its glass transition appears at a much lower temperature of 88 °C. As for TSPC and TSDC, a very small peak associated with the glass transition appears at about 110 °C. Furthermore, a much clearer TSPC peak due to orientation of dipole moments associated with the ether linkage induced by the cross‐linking reaction appears at about 150–170 °C. The corresponding TSDC peak due to randomization of these dipoles is very small compared to the TSPC peak, since PPS was cross‐linked during the high‐temperature process in the TSPC measurement, which made rotation of the dipoles difficult. At temperatures higher than 150 °C, both the real and imaginary parts of the complex permittivity show significant increases with increase in temperature and decrease in frequency. This is attributable to the transport of the charge carriers. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

VRB用季铵化聚醚砜阴离子交换膜

对聚醚砜(PES)进行氯甲基化、季铵化改性,制备了季铵化PES(QAPES)阴离子交换膜,考察了不同离子交换容量(IEC)膜的含水率、面电阻(R)、化学稳定性及单体全钒氧化还原液流电池(VRB)的性能。IEC为1.47 mmol/g的QAPES膜的R为0.66Ω.cm2,在1.5 mol/L VO2+溶液中浸泡30 d,质量损失为4.5%,单体VRB的能量效率可达84.4%。     

磺化聚醚醚酮膜的制备及性能

采用浓硫酸(95%～98%)作为磺化剂,制备了具有不同磺化度(DS)的磺化聚醚醚酮(SPEEK)膜,用FT-IR和1H NMR对SPEEK的结构进行了表征,用1H NMR法对磺化度进行了测定,并对SPEEK膜的质子导电性能进行了研究.磺化度为0.78时,SPEEK膜的质子传导率在115℃时达到了5.8×10-2S/cm.温度对SPEEK膜的质子传导性能有着显著的影响,在25℃下,SPEEK膜的质子传导活化能都超过了25kJ/mol.     

改性含氮杂环聚醚砜酮绝缘漆的合成、表征及应用研究

以合成的含二氮杂萘酮结构的聚醚砜酮(PPESK)为基础，然后对其进行羟基化改性，用FT-IR和^1H-NMR表征分子链结构，并和小分子量的聚氨脂发生交联反应制成了性能良好的绝缘漆。     

聚醚酰胺树脂的研究

在22篇文献的基础上对聚醚酰胺树脂最新研究进展进行了综述;比较了双噁唑啉的两种制备方法,介绍了双噁唑啉改性酚醛树脂或苯并噁嗪树脂的原理、固化物性能。     

胺化条件对季铵化PPEK膜性能的影响

以氯甲基化杂萘联苯聚醚酮(CMPPEK)为膜材料,通过溶液法制备了CMPPEK基膜,然后将其浸泡在三甲胺水溶液中进行季铵化反应得到季铵化杂萘联苯聚醚酮(QAPPEK)阴离子交换膜。比较了CMPPEK和QAPPEK的热失重性能,CMPPEK的5%热失重温度为330℃,QAPPEK的5%热失重温度为260℃,QAPPEK的5%热失重温度与CMPPEK的相比降低了70℃。考察了三甲胺浓度、胺化时间、胺化温度等反应条件对QAPPEK膜性能的影响。结果表明:三甲胺的质量分数为33%、胺化时间为12h、胺化温度为40℃时,得到的QAPPEK膜表现出了较优异的性能,其IEC值达1.64mmol/g,在2mol/LVOSO4+3mol/LH2SO4的混合溶液中测得的面电阻为0.73Ω·cm2,应用于全钒液流电池(VRB)中,电池的能量效率高达85.9%,电流效率为98.4%,电压效率为87.3%。     

Finite element analysis of temperature distribution of polycrystalline silicon thin film transistors under self-heating stress

The temperature distribution of typical n-type polycrystalline silicon thin film transistors under self-heating (SH) stress is studied by finite element analysis. From both steady-state and transient thermal simulation, the influence of device power density, substrate material, and channel width on device temperature distribution is analyzed. This study is helpful to understand the mechanism of SH degradation, and to effectively alleviate the SH effect in device operation. __________ Translated from Journal of Semiconductors, 2008, 29(5): 954–959 [译自: 半导体学报]     

PEMFC用Ce-MCM-41/SPEES复合膜的研究

室温下,通过非水热合成法制备了Ce-MCM-41淬灭剂,通过XRF、FT-IR、XRD等表征显示了Ce4+很好地插入到MCM-41骨架中,TEM表征了Ce-MCM-41的多孔结构,利用二甲基亚砜(DMSO)作为捕获剂通过UV-VIS光谱方法表征了Ce-MCM-41淬灭剂捕获自由基的能力.为了降低燃料电池条件下自由基(HO·)对膜的降解制备了Ce-MCM-41/SPEES复合膜,通过离线Fenton实验和在线加速开路降解实验观察了膜的稳定性,结果显示了Ce-MCM-41/SPEES复合膜的稳定性得到了提高.     

纳米SiO2增强脲醛树脂机械性能的分子模拟研究

介电材料广泛应用于现代电网,但容易出现开裂现象,引起局部放电、电树枝等危害。将芯材为双环戊二烯,壁材为脲醛树脂(PUF)的自修复微胶囊掺杂进介电材料,可实现材料的自修复。但PUF微胶囊硬度不足,其机械性能需要增强。文中采用分子模拟方法建立3组模型,每组分别包括一个纯PUF模型和一个掺杂纳米SiO2的PUF模型,经过计算后分析其密度、自由体积分数、机械性能,建立PUF/SiO2界面相互作用模型以挖掘其内部机理。结果发现,掺杂纳米SiO2有利于增大PUF材料的密度,减小自由体积分数、增强其机械性能。原因是PUF链上的极性原子和纳米SiO2表面的羟基、O原子之间存在氢键相互作用。文中采用分子模拟技术揭示了纳米SiO2增强PUF机械性能的内部机理。     

Fabrication and structural characterization of interdigitated thin film La1 − x Sr x CoO 3 (LSCO) electrodes

For the prospective use as micro-Solid Oxide Fuel Cell (μ-SOFC) cathodes and for the investigation of reaction kinetics, La_{1 − x}Sr_xCoO₃ (LSCO) mixed ionic electronic conducting thin films were deposited by DC and RF sputtering onto a number of different substrate materials and characterized. Standard photolithographic and wet chemical etching methods were utilized to microstructure the LSCO films and XRD, SEM, AFM, WDS, and RBS were used to characterize their structure, topography, and chemistry. Sputtering resulted in very homogeneous and smooth thin crystalline films with Sr deficiency and submicron sized grains. Hydrochloric acid was found to readily etch LSCO with the etching quality strongly dependent on substrate material. LSCO films were most easily etched when deposited directly on silicon substrates, etched at intermediate rates when deposited on Gd:CeO₂ films, and most resistant to etching after deposition onto single crystal yttria stabilized zirconia (YSZ) substrates. Imperfect etching was attributed to interface formation and the presence of impurities.