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1.
以端羟基聚环氧氯丙烷(PECH)为原料,用直接合成法通过季铵化反应一步合成了聚醚N甲基咪唑氯盐([PECH-NMIM]Cl)、聚醚喹啉氯盐([PECH-QL]Cl)、聚醚吡啶氯盐([PECH-PY]Cl)、聚醚N甲基吗啉氯盐([PECH-NMM]Cl)等4种阴离子为氯离子的聚醚季铵盐。再以聚醚季铵盐和四氟硼酸钠为原料,用离子交换法通过置换反应一步合成了聚醚N甲基咪唑四氟硼酸盐([PECH-NMIM]BF4)、聚醚喹啉四氟硼酸盐([PECH-QL]BF4)、聚醚吡啶四氟硼酸盐([PECH-PY]BF4)、聚醚N甲基吗啉四氟硼酸盐([PECH-NMM]BF4)。考察了反应温度、反应配比、反应时间、PECH的数均分子量对季铵化反应取代度的影响;用红外光谱和核磁共振氢谱对聚醚离子液体进行了结构表征。  相似文献   

2.
聚醚类表面活性剂的物化性质   总被引:6,自引:0,他引:6  
通过对聚醚的物化性质(临界胶束浓度、乳化力、渗透性、热分解性及粘温特性)的测试,得出了聚醚链段结构上环氧乙守和环氧丙烷排列不同时对其物化性质的影响规律,发现嵌段聚醚和无规聚醚在其物化性质上存在“质”的区别,嵌段聚醚的乳化性、渗透性与热分解性质都好于无规聚醚,而临界胶束浓度、浊点明显低于规聚醚,两者的粘温曲线相似,但嵌段聚醚的粘度值大于相应的无规聚醚。  相似文献   

3.
用酸碱中和法和离子交换法由磺化聚醚酮酮制得了一价型聚醚酮酮磺酸盐和二价型聚醚酮酮磺酸盐。IR分析表明,两种方法制备的价数相同的聚醚酮酮磺酸盐有相似结构;TG分析表明,一价型聚醚酮酮磺酸盐的热分解发生在520℃;而二价型聚醚酮酮磺酸盐在370℃有一失去磺酸基的小热分解峰,520℃发生主链的热分解。  相似文献   

4.
把聚醚多元醇加入电解质中,会对电解电容器的漏电流(Ic)、损耗(D)和电容量(C)产生影响。聚醚对漏电流的影响与它在电解质中的含量有关,聚醚GE对电容器的漏电流的减小作用比聚醚JE大。聚醚还可以提高电解液的闪火电压(Us),延长阳极氧化铝膜的耐压时间,延长电容器的寿命。  相似文献   

5.
通过静态试验,研究了两种截留分子量的聚醚砜、聚醚酮、磺化聚砜/聚醚砜、磺化聚砜/聚醚酮等超滤膜处理碱法草浆黑液的超滤特性,结果表明:静态接触条件下,聚醚砜及磺化类膜受黑液组份的污染程度较轻,聚醚酮膜的污染程度最重;荷负电性较高的磺化类膜具有较好的黑液超滤特性;截留分子量2万的超滤膜特性要优于5万的膜。  相似文献   

6.
EO/PO无规共聚醚的浊点研究   总被引:1,自引:0,他引:1  
研究了无规共聚醚水溶液的浓度、无规共聚醚结构度无机电解质、酸、醇、表面活性剂对浊点的影响。结果表明所选择的电解质均能降低聚醚的浊点;酸能轻微提高聚醚的浊点;水溶性醇和非水溶性醇的影响效果不同,前者能提高聚醚的浊点,后者则使之降低;表面活性荆能提高聚醚的浊点;随着聚醚中聚氧乙烯基含量的增加,其浊点升高;相对分子质量增加,使浊点降低。这些规律对无规聚醚的研究和应用有一定的指导意义。  相似文献   

7.
以苯乙烯和丙烯腈在聚醚多元醇介质中分散聚合制备了聚合物聚醚多元醇.测定了聚合物聚醚多元醇中粒子大小和体系的流变曲线.聚合物聚醚多元醇的流变曲线呈现“剪切增稠→剪切变稀”的非牛顿特性.用Gillespie公式对流变曲线进行了数据分析,由此计算出各聚合物聚醚多元醇的η^*,Ф表观和3种聚合物聚醚多元醇中粒子间相对“键合”能.  相似文献   

8.
综述了硅烷改性聚醚化合物的结构、制备方法、交联固化机理及硅烷改性聚醚密封胶研究进展及其在装配式建筑、土木工程及工业领域中的应用,并对硅烷改性聚醚基础聚合物制备路线及硅烷改性聚醚密封胶未来的发展方向进行了展望.  相似文献   

9.
用改性聚硅氧烷和低分子量的聚醚形成的嵌段共聚物制备聚醚消泡剂 ,以水系乳胶漆进行消泡试验 ,并进行了性能测试分析 ,结果显示 ,聚醚改性有机硅消泡剂具有良好的消泡性能 .  相似文献   

10.
运用XUD-9法来探究聚烯胺清净单剂、聚醚胺清净单剂以及聚烯胺与聚醚胺复合清净剂的清净效果,并探究聚烯胺与聚醚胺的最佳复合比例.试验结果表明,聚烯胺清净剂的清净效果相比于聚醚胺清净剂的清净效果更好一些,复合清净剂的清净效果要明显优于清净单剂的清净效果,聚烯胺:聚醚胺比例为3:1的复合型柴油清净剂的喷嘴空气流量损失最小,...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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