乙酸乙烯酯嵌段共聚物的合成研究

以ＡＩＢＮ为引发剂，用ＣＣｌ４调节乙酸乙烯酯聚合制备了带三氯甲基端基的ＰＶＡｃ大分子引发剂（ＰＶＡｃ－ＣＣｌ３）。以ＣｕＣｌ－ｂｐｙ为催化剂，用ＰＶＡｃ－ＣＣｌ３引发Ｓｔ，ＭＭＡ和ＢＭＡ等单体的ＡＴＲＰ聚合，得到了一系列相对分子质量可控、相对分子质量分布较窄的ＰＶＡｃ嵌段共聚物。     

三元偏氯乙烯/丙烯腈/苯乙烯悬浮共聚树脂的合成

以偶氨二异丁腈（ＡＩＢＮ）作引发剂,合成了偏氯乙烯（ＶＤＣ）／丙烯腈（ＡＮ）／苯乙烯（Ｓｔ）三元悬浮共聚树脂。在聚合过程中,压力先逐步升高后下降。当悬浮聚合质量投料比为６０：１５：２５（ＶＣＤ／ＡＮ／Ｓｔ）时,其压力转变点的转化率约为５５％～６５％。聚合得到的三元ＶＤＣ－ＡＮ－Ｓｔ悬浮共聚树脂为球形半透明颗粒,重均粒径约为５０．５６μｍ。合成的悬浮液中存在数量较多的微小粒子,加入ＮａＮＯ２可减少其     

无皂乳液聚合制备阳离子功能性微示研究

苯乙烯（Ｓｔ）／丙烯酸丁酯（ＢＡ）体系在无乳化剂的条件下分别与少量的自制的Ｎ，Ｎ－二甲基，Ｎ－丁基，Ｎ－甲基丙烯酰氧乙基溴化铵（ＤＢＭＥＡ）、Ｎ，Ｎ－二甲基，Ｎ－丁基，Ｎ－（３－甲基丙烯酰胺基）丙基溴化铵（ＤＢＭＰＡ）进行共聚，难过离子交换－－电导滴定确定了两体系微球表面基团及粒子表面电荷密度，认为微球大小及表面电荷密度主要由引发剂浓度、共聚单体浓度、离子强度、Ｓｔ／ＢＡ主单体比及单体加料方式决定     

宽分子量分布聚氯乙烯的合成与特性

在氯乙烯（ＶＣ）气相聚合中，改变反应相对压力并以二段气相聚合法，合成了宽分子量分布的聚氯乙烯（ＢＭＤ－ＰＶＣ）并对所得聚氯乙烯的热稳定性及加工性（熔体粘度和塑化时间）进行了研究，分子量分散指数在聚合相对压力为０．５时达到最高，为４．２。该法聚合得的聚氯乙烯中叔碳氯和烯丙基氯的含量是随着分子量减少而增加，因此，脱氯化氢量也随分子量减小而增加。塑化流动性主要受ＢＭＤ－ＰＶＣ中所含有的低聚合度组分含量影     

PBA－g－AS共聚物的合成

本文以交联ＰＢＡ为主链，ｇｒ和ＡＮ为接技单体，通过乳液接枝共聚会成了ＰＢＡ－ｇ－ＡＳ井聚物．研究了乳化剂加入量、引发剂种类及用量、单体加入方式及单体浓度、反应时间以及ＰＢＡ胶乳性质等对接枝率、转化率及粒子形态的影响，同时也研究了ＴＤＭ用量对接枝链分子量及接枝率的影响．     

高单体进料浓度下丙烯腈连续水相沉淀共聚的研究

以ＫＰＳ－ＮａＨＳＯ３－Ｆｅ＾２＋为氧化还原引发体系,在５升ＣＳＴＲ中进行了高单体进料浓度的丙烯腈（ＡＮ）－丙烯酸甲酯（ＭＡ）＿苯乙磺酸钠（ＳＳＳ）三元水相沉淀共聚,系统考察了单体进料浓度、引发剂浓度及还氧比、ＰＨ值、聚合温度、平均停留时间和搅拌条件等工艺因素对聚全转化率和分子昨及其分布的影响。结果表明,在充分搅拌混合的前提下提高单体进料浓度可提高转化率,由此引起的分子量增加可通过提高引发剂相对用     

聚合物载体－稀土金属络合物的研究 Ⅻ．聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］载体－三氯化钕络合物－三异丁基铝体系催化丁二烯聚合的活性

研究了聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］（ＰＳＭ）载体－三氯化钕（ＮａＣ１３）络合物－Ａｌ（ｉ－Ｂｕ）３体系催化丁二烯聚合的活性与ＰＳＭ转化率和ＰＳＭ·ＮｄＣｌ３络合物组成的关系。实验结果表明，ＰＳＭ转化率为１８．１％～５３．４％，对ＰＳＭ·ＮｄＣｌ３－Ａｌ（ｉ－Ｂｕ）３体系的活性基本上无影响。低功能团含量的ＰＳＭ·ＮｄＣｌ３络合物的活性优于高功能团含量的ＰＳＭ·ＮｄＣｌ３。该络合物中Ｎｄ含量为４．５×１０（－４）ｍｏｌ／ｇ左右时，体系的催化活性最佳。体系的活性随引入的Ｌｅｗｉｓ酸的种类和用量的不同而改变。     

油溶性氧化还原引发剂引发苯乙烯乳液聚合反应动力学的研究 过氧化月桂酰胺N,N-二丁基苯胺引发行为的研究

本文详细地研究了过氧化月桂酰胺（ＬＰＯ）／Ｎ,Ｎ－ 二丁基苯胺（ＤＢＡＮ） 引发苯乙烯乳液聚合反应的动力学行为。检测了聚合反应速率,聚合物粒子数,以及聚合物的分子量随引发剂ＤＢＡＮ／ＬＰＯ比率的变化。分析这些实验结果,从中发现聚合反应的极限转化率取决于ＤＢＡＮ／ＬＰＯ 的比值,表观聚合反应速率是由发生在聚合物粒子中和在单体液滴中的聚合反应两部分组成。聚合反应总速率取决于ＤＢＡＮ／ＬＰＯ 的比值。聚合物粒子数随ＤＢＡＮ／ＬＰＯ 的比值的增加而增加。而且聚合物的分子量则随ＤＢＡＮ／ＬＰＯ 的浓度增加而减少。并且也讨论了在该反应系统中的聚合物分散指数ＰＤＩ的变化,和聚合物粒子的成核机理及影响粒子分散度的原因     

WCl_6－Al（i－Bu）_2Cl催化丁二烯－苯乙烯共聚合──丁苯共聚物的结构组成和竞聚率测定

对丁苯共聚物的~１Ｈ－ＮＭＲ谱图进行了归属，并建立了计算其４种结构单元含量的方程式。当Ａｌ（ｉ－Ｂｕ）_２Ｃｌ／ＷＣｌ_６＝６（摩尔比）时，苯乙烯（Ｓｔ）单元含量最低，丁二烯（Ｂｄ）单元含量最高；Ｂｄ单元含量随Ｂｄ／Ｓｔ值的增加而提高，总的Ｓｔ单元含量随Ｂｄ／Ｓｔ值的增加而降低；聚合时间对单元含量的影响与Ｂｄ／Ｓｔ值的影响相似；提高聚合温度，Ｓｔ单元含量降低。用微分法求得转化率低于１０时Ｓｔ的竞聚率为４．７０，Ｂｄ的竞聚率为０．２７。     

WCl6—Al（i—Bu）2Cl催化丁二烯—苯乙烯共聚合：丁苯共聚物的结构组…

对丁苯共聚物的＾１Ｈ－ＮＭＲ谱图进行了归属，并建立了计算其４种结构单元含量的方程式。当Ａｌ（ｉ－Ｂｕ）２Ｃｌ／ＷＣｌ６＝６（摩尔比）时，苯乙烯单元含量最低，丁二烯单元含量最高；Ｂｄ单元含量随Ｂｄ／Ｓｔ值的增加而提高，总的Ｓｔ单元含量随Ｂｄ／Ｓｔ值的增加而降低；聚合时间对单元含量的影响与Ｂｄ／Ｓｔ值的影响相似；提高聚合温度，Ｓｔ单元含量降低。用微分法求得转化率低于１０％时Ｓｔ的竞聚率为４．７０，Ｂｄ     

乙苯,苯乙烯的生产及合成乙苯,苯乙烯催化剂的研究进展

苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况，合成乙苯，苯乙烯所用的催化剂种类，并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。     

Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile

Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, ¹³C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc.     

生物质气化及生物质与煤共气化技术的研发与应用

总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。     

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu₃Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu₃Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.     

钾盐资源及钾肥供需情况分析及预测

阐述了国内外钾盐资源及钾肥生产现状,对国内外钾盐的供需形势进行了分析及预测,从资源、原材料、国际市场三方面提出了解决我国钾盐短缺的措施。     

Kinetics and Mechanism of Oxidation of Mono- and Polyacetals

Abstract

Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed.     

Comparison of the Adhesion and Cohesion of Triblock and Random Copolymers of Styrene and Butadiene

A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength.     

责任和责任心的涵义与结构

责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.     

二甲基二烯丙基氯化铵和丙烯酰胺的合成及应用

用复合引发体系(过硫酸盐-偶氮类引发剂)和脂肪胺类氧化还原体系引发,在实验室获得了单体转化率≥98%,特性粘数高于13.6 dL/g的阳离子共聚物PDA,探讨了控制聚合物分子量的影响因素.     

Wetting properties of homopolymers and copolymers of pentafluorostyrene and methylacrylate and homopolymer blends

Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method¹ was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity.