BA—St—MMA三元共聚压敏胶正交试验研究

介绍了用偶氮二异丁腈为引发剂，甲苯为溶剂，丙烯酸丁酯（BA），甲基丙烯酸甲酯（MMA）及苯乙烯（St)三元共聚合成丙烯酸酯压敏胶粘剂的方法；应用正交试验对合成工艺参数进行了优化；结果表明：在共聚温度65℃，St用量35ml,MMA用量30ml,AIBN用量为2.5g的条件下，可获得剥离强度16.4N/25mm的压敏胶粘剂，在共聚温度70℃，St用量30ml,MMA用量30ml,AIBN用量为2.5g条件下，可获得固含量66%的压敏胶粘剂。     

SIS/甲基丙烯酸酯接枝改性胶粘剂的研制

以甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA)为单体,或以其混合物为接枝单体,对聚苯乙烯-聚异戊二烯-聚苯乙烯(SIS)进行接枝共聚制备溶剂型胶粘剂.研究了引发剂用量、单体配比、反应温度及反应时间对胶粘剂性能的影响.结果表明:单体MMA的适宜用量为SIS总质量的15%左右,BMA的用量为SIS质量的20%,MMA与BMA适宜配比为2∶1,引发剂用量为SIS总质量的1.0%,反应温度为85℃,反应时间为4 h左右.     

SBS-g-MMA悬浮接枝共聚物的合成研究

以过氧化二苯甲酰(BPO)为引发剂,水为分散相,用即可作溶剂又可作共聚单体的甲基丙烯酸甲酯(MMA)与SBS在开放体系下进行悬浮接枝共聚反应．并用红外光谱对接技物进行了表征,同时通、过正交实验探讨了最佳合成工-g：MMA／SBS为11．6：1(质量比),BPO用量为SBS的0．5％,在温度为75℃条件下反应4．0h,可得到接枝率为86．3％的SBS-g-MMA接枝共聚物．     

乙烯基单体乳液接枝改性氯丁胶乳的制备及其机理

采用乳液聚合法,使用氧化还原引发剂,将乙烯基单体(甲基丙烯酸甲酯和苯乙烯,即MMA和St)接枝到氯丁胶乳上,研究了乳化体系、引发体系、单体/聚合物质量比及单体组成、反应温度对单体转化率、接枝效率等的影响,并进一步分析了乳液接枝机理.结果表明,MMA和St接枝改性氯丁胶乳的最佳工艺条件为:聚合温度50℃,反应时间5.5h,引发剂叔丁基过氧化氢-四乙烯五胺占氯丁胶乳干重的0.5%,单体/聚合物质量比为3:5,MMA与St质量比为3:2,单体以滴加方式加入,乳化剂十二烷基苯磺酸钠用量占单体总重1.5%.在此条件下,单体转化率可达99.6%,接枝效率为54.9%.红外光谱和凝胶含量分析证明MMA和St接枝到氯丁胶乳主链上.该条件下合成的接枝共聚物乳液配制成的胶粘剂对PVC人造革、SBS橡胶、海绵等具有良好的粘接性能.接枝反应活性点在氯丁胶乳胶粒的表面,接枝过程是一个表面控制过程.     

氯丁橡胶和MMA接枝共聚胶粘剂的研制

研制了氯丁橡胶(CR)与甲基丙烯酸甲酯(MMA)接枝共聚胶粘剂,探讨了聚合反应温度、引发剂用量、单体MMA用量及加入方式、有无氮气保护和CR/溶剂配比对单体接枝率和接枝共聚产物性能的影响,确定了适宜反应条件和配方组成.     

聚羧酸高效水泥减水剂的合成及性能

采用先酯化后共聚的方法合成聚羧酸系减水剂,考察以甲基丙烯酸(MMA)和甲氧基聚乙二醇(MPEG)为原料酯化合成大单体甲氧基聚乙二醇甲基丙烯酸酯(MPEGMA)过程中阻聚剂对苯二酚用量、酸醇摩尔比、反应温度等对酯化率的影响.以大单体MPEGMA与马来酸酐、MMA和2丙烯酰胺基2甲基丙烷磺酸共聚合成聚羧酸类减水剂,考察减水剂合成过程中MPEG相对分子质量和引发剂过硫酸铵用量以及减水剂掺量对减水剂性能的影响.结果表明:阻聚剂质量分数为0.4%、酸醇摩尔比为1.5:1、反应温度为120℃时,酯化率可达到92.3%.当MPEG相对分子质量为1000、引发剂的质量分数为5%,合成的减水剂掺量质量分数为0.3%时,水泥的净浆流动度可达281mm.     

乙烯基单体乳液接枝改性氯丁胶乳的制备及接枝机理研究

采用乳液聚合法,使用氧化还原引发剂,将乙烯基单体（甲基丙烯酸甲酯MMA、苯乙烯 St）接枝到氯丁胶乳上。研究了乳化体系、引发体系、单体/聚合物配比（M/P）及单体组成和反应温度对单体转化率、接枝效率等的影响,分析了乳液接枝机理。结果表明, MMA和St接枝改性氯丁胶乳的最佳工艺条件为：聚合温度为50℃,反应时间5.5h,引发剂叔丁基过氧化氢一四乙烯五胺（t-BHP/TEPA）用量占氯丁胶乳干重的0.5 %,M：P =3：5,WMMA：WSt=3:2,单体以滴加方式加入,乳化剂十二烷基苯磺酸钠 （SDBS）用量占单体总重1.5%,此时单体转化率可达99.6%,接枝效率为54.9%。红外光谱和凝胶含量分析证明MMA和St接枝到氯丁胶乳主链上。在最佳条件下合成的接枝共聚物乳液配制成的胶粘剂对PVC人造革、SBS橡胶、海绵等具有良好的粘接性能。接枝反应活性点在氯丁胶乳胶粒的表面,接枝过程是一个表面控制过程。     

三维多孔锂电池材料合成模板剂聚甲基丙烯酸甲酯(PMMA)微球的制备研究

采用单分散聚合法和种子溶胀法,在乙醇/甲醇体系中以甲基丙烯酸甲酯(MMA)为单体、偶氮二异丁腈(AIBN)为引发剂、聚乙烯吡咯烷酮(PVP)为分散剂制备聚甲基丙烯酸甲酯(PMMA)高分子微球,并以此作为后继制备三维(3D)多孔结构锂电池材料的合成模板剂.讨论两种合成方法获得微球的粒径均匀性和粒径分布,认为单分散聚合法能获得较为理想的模板剂,研究此方法中单体介质比和引发剂浓度对微球粒径和分散性的影响,得出最佳合成条件为:MMA/medium=13.8%(质量分数,全文同),AIBN=6g时,合成微球的粒径最均匀,平均为3.8μm,粒径分布为0.103 2.     

非均相合成PP-g-MMA共聚物研究

非均相合成了甲基丙烯酸甲酯 (MMA)和聚丙烯 (PP)的接枝物 (PP—g—MMA) .对合成产物进行了IR表征 ,考察了引发剂PBO、甲苯、反应时间和单体等对接枝率和接枝效率的影响 .结果表明 ,在BPO引发下 ,MMA能被接枝到PP链上 ;甲苯的加入对提高接枝率不利 ,单体用量的改变对接枝率的影响较大 ;反应最佳工艺条件为温度 :86℃ ,时间 :2 .5h ,配方 :PP/g∶MMA/mL∶BPO/g=2 0∶1 0∶0 .3.     

丙二腈存在下苯乙烯-甲基丙烯酸甲酯的活性无规共聚研究

研究了少量丙二腈对稳定自由基(TEMPO)存在下苯乙烯(St)和甲基丙烯酸甲酯(MMA)无规共聚的影响,发现丙二腈对于该共聚体系具有明显的加速效果.丙二腈与TEMPO的摩尔比在2.5:1时加速效果最好,在125℃下聚合30min转化率可达93%.共聚产物分子量随转化率增大而增大,分子量分布较窄(1.1～1.5).聚合速率随St在单体中的比例提高而减小.在MMA的单体比例较大时仍能得到分散性小的共聚物.     

Markedness and its Interpretation in Language Use

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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