使用2种硅烷偶联剂(KH550和KH792)对介孔分子筛MCM-41进行表面改性,采取氮气吸附-脱附、FTIR和TGA等进行表征,并采用原位聚合法制备了MCM-41/环氧树脂复合材料,研究了偶联剂种类和MCM-41用量等对复合材料固化过程及性能的影响.结果表明:硅烷偶联剂可与MCM-41表面的硅羟基反应,在分子筛内外表面接枝上功能化基团.经表面修饰的MCM-41比表面积下降为原来的1/5,KH550在MCM-41表面接枝率仅为KH792的一半.KH550与MCM-41外表面反应得更充分,KH792对MCM-41孔道内壁的修饰效果更强.固化动力学结果表明:KH792的功能化基团有伯胺和仲胺,与环氧树脂具有更高的反应活性,但不利于环氧大分子进入孔道,仅以球形粒子的形式添加在环氧树脂中;KH550表面修饰的MCM-41可使环氧大分子进入孔道内形成互穿结构.KH550表面修饰体系更多体现出MCM-41多孔的特征,形成了有机-无机互穿结构的复合体系,大幅度提高了储能模量和玻璃化转变温度.KH792表面修饰体系则呈常规球形纳米粒子的特征,其储能模量和玻璃化转变温度较纯环氧树脂有所提高但幅度不大.

The primary current of power system may increase several or even multiple times while power system faults occur.In this condition,the iron core of protective current transformer will become saturated,which causes the distortion of secondary current and affects the operation of protection relay and other secondary equipments.In this paper,the saturated characteristics of protection current transformer are analyzed,the methods of plotting error curve and checking secondary load are introduced,and the measure of reducing error for protection current transformer is presented.

For improving the arc ablation resistance of nozzle materials of high-voltage circuit breaker,it is needed to fill Al 2 O 3 and TiO 2 in PTFE to reduce the ablation of arc energy and improve the arc ablation resistance of nozzle.The regularity of dielectric property of PTFE has been achieved by experimental study.According to the study,the arc ablation was improved by filling the inorganic materials in PTFE,and the important influence factors of the arc ablation seem to be filler content and particle size.Dielectric constant and loss factor of PTFE composites increase with increasing filler content.Dielectric constant of PTFE composites decrease when temperature increases,but loss factor of PTFE composites increase with temperature increment.The results provide guidance for the application to production.

Using ultrasonic wave process,the nano-silica powder was dispersed in epoxy resin efficiently,then the diversion scene was observed through TEM.the relation of frequency with dielectric constant(e r )and dielectric loss factor(tanδ)were researched.The results indicate that thee r of nano-silica/epoxy composites decrease with the increase of frequency;tanδincrease with the content increase of nano-silica in nano-silica/epoxy composites,but become flat in the high-frequency region.

According to technique requests of anticorrosion of pipeline tie-in and characteristic of polyole-fine,kinds of comonomers were added to graft with SBS,new hot melt pressure sensitive adhesives were developed.After analyzing the constitution of the adhesive and relationships of them.And effects of resin content and time on reaction were studied with trials.Experimental results indicate that bond strength of the adhesive is the best when resin content is sixty to eighty percent and time on reaction is one and half an hour on condition that the ratio of comonomers are fixed.

为提高综合性能,用少量有机硅树脂对环氧树脂进行改性,然后利用多功能电子能谱研究复合体系中有机硅树脂的迁移特性,研究有机硅与环氧树脂复合体系的介电温谱和动态力学性能.结果表明,在环氧树脂复合体系中,有机硅树脂具有表面富集趋势;随着硅树脂浓度的增加,相对介电常数减小,介质损耗因数在低温区无明显改变,而在高温区则有较明显的增大;贮能模量随硅树脂浓度的增加而降低,损耗模量峰值随之而升高.

The theory and structure of the optical voltage transducer is introduced in this paper, which focuses on the electric field calculation and analysis of the sensors with different shapes of crystals under flat electrodes and arcual ones respectively. According to the calculated results, the uniformity of electric field distribution can be improved and the centralization effect can be reduced by means of the combination of different crystal shapes with different shapes of electrodes. So the withstand voltage and the stability and the accuracy of the measurement could be increased effectively.

A theoretical model of nozzle ablation is proposed based on the analysis of nozzle materials and arc energy conversion. According to the simulation results, adding 1-5 percent filler into the main material can increase the arc energy absorbed by the nozzle, and the nozzle characteristics against the ablation can be improved efficiently. When the filler grain is larger than 10 micron, the starting ablation time can be prolonged. The research provides a theoretical basis for increasing the nozzle behavior against the arc ablation and prolonging the lifetime of SF6 circuit breaker.

研究电介质与半导体之间的接触带电、带电规律和带电控制,可有效地控制电力电子器件表面绝缘保护材料与半导体表面相互作用而形成的不同界面态和界面电荷,优化台面型电力电子器件表面空间电荷区宽度、表面电场分布,提高表面耐压.对加入不同填料的聚酯改性硅漆(SP),测量其与表面氧化和表面钝化的n型和p型硅片接触后表面带电极性和带电量,得出一个接触带电序列.接触带电序列表明,绝缘保护材料与各种硅片的接触,实质上是保护材料与硅片表面物质的接触,与硅片的类型和内部结构无关.

在分析高压SF6断路器开断大电流时,电弧对喷口烧蚀机理的基础上,进行了喷口材料改性试验研究.得出聚四氟乙烯中加入MoS2,BN,光致蓄光材料(PL),复合聚四氟乙烯的介电性能、光学性能、耐电弧烧蚀性能和线膨胀系数的变化规律.研究结果为提高喷口的耐电弧烧蚀性能、改善喷口材料的介电性能和工艺性提供了理论依据.