双组分共混体系中晶相结晶行为

含结晶组分的双组分共混体系，其中的结晶组分的结晶行为会受到另一组分的影响，进而影响到材料的结构与性能。本文总结了近年来含结晶相的聚合物共混物在改性过程中，共混与添加组分对晶相结晶速率、晶型比例、晶体尺寸等结晶行为的影响。     

分子量多分散性对AB二嵌段共聚物相行为的影响

采用Monte Carlo方法研究了分子量多分散性对AB型嵌段共聚物相行为的影响. 通过调整嵌段共聚物中组分含量, 考察了整体多分散性和单嵌段多分散性对嵌段共聚物共混物的有序-无序转变(Order-disorder transition, ODT)、 形貌及链尺寸的影响. 研究结果表明, 多分散度的增大使无序相向较大χN区域略微移动, 形成的片层结构厚度增加. 在形成微观有序形貌后, 较大分散度时各亚组分的链会得到更大的伸展, 表明分子链堆积受挫的程度减小, 因此, 涨落作用受到的抑制作用减小, 无序相区向更低温度区域移动.     

AB交联聚合物的形态

以低分子量的端乙烯基聚氨酯预聚物同乙烯类单体共聚制得的AB交联聚合物(ABCP)呈现出两相形态结构,聚氨酯相形成分散相,塑料组份形成连续相。形态结构最显著特点是分散相区呈现出多分散性;其次,分散相区的形状不规则。这些特征不同于线型AB、ABA嵌段共聚物及A_2B接枝共聚物,这是由于ABCP中,A和B两组份间存在着化学交联。交联密度,预聚物的分子量对两组份的相容性,形态结构有显著影响。     

高聚物的分子量和分子量分布

引言高聚物最明显的特点是它的分子量大,一般比小分子化合物的分子量大2到5个数量级。除某些天然聚合物以外,合成聚合物的分子量还有多分散性,这就是说,高聚物试样中的各个高分子之间的聚合度可以不相同,因而试样的分子量有一个分布。高聚物的分子量分布表征试样中不同分子量的分布情况。高聚物     

填料对聚合物共混物相分离行为的影响

近年来,由于粒子填充聚合物共混物的广泛运用,复合材料的结构研究具有重要意义.除了研究粒子在聚合物中的分散外,关于粒子对聚合物共混物的相分离影响也做了大量工作.研究结果表明粒子的尺寸,粒子的表面处理以及粒子含量对聚合物共混物相分离热力学以及动力学有重要影响.由于粒子对聚合物组分的选择吸附、聚合物分子对粒子的润湿作用、填料对聚合物相区生长的阻碍导致了聚合物共混物-填料体系相行为的复杂性.本文扼要地综述了聚合物共混物-填料体系相分离的理论基础以及实验结果,介绍了粒子对相分离的影响因素,并展望了该领域的研究趋势和前景.     

超高分子量聚乙烯／聚丙烯共混体系流变行为及形态的研究

超高分子量聚乙烯／聚丙烯共混体系流变行为及形态的研究汪晓东,励杭泉,金日光（北京化工大学高分子系,北京,１０００２９）关键词共混合金,线性互穿网络,双连续相,网络增韧机理通常聚合物的增韧机理是在树脂中引人柔性链段［１］形成复合物（如橡塑共混物）,这些...     

动态流变法在聚合物/聚合物界面分子链扩散研究中的应用

聚合物/聚合物界面的分子链扩散问题在塑料注塑、焊接、共混等领域普遍存在.动态流变法是研究聚合物/聚合物界面分子链扩散的一种有力手段,这种方法对于界面间分子链扩散的监测非常灵敏.本文简述了用动态流变法研究聚合物/聚合物界面扩散的原理、实验方法以及优点,着重讨论了采用该方法研究初始界面分子链末端分布对扩散机理的影响、对称聚合物/聚合物界面分子链扩散的量化,非对称聚合物/聚合物界面的相互扩散,分子量多分散性对聚合物/聚合物界面扩散的影响,聚合物/聚合物界面间的流动和扩散耦合以及近年来动态流变法在化学反应型聚合物/聚合物界面的应用进展.     

双亲三嵌段共聚物PEO-PPO-PEO在水溶液中相行为的理论研究

用自洽平均场理论的谱方法研究了双亲三嵌段共聚物PEO-PPO-PEO的分子量对其在水溶液相行为的影响. 理论预测了各种溶致液晶相的稳定区域. 通过系统地改变聚合物的分子量, 我们给出了各种PEO-PPO-PEO三嵌段共聚物在水溶液中的相图. 此外, 也研究了分子量对自组装结构各组分浓度分布的影响. 发现在给定的温度下, 聚合物的分子量是体系发生相分离的一个重要驱动力. 我们的理论结果与相关的实验很好地符合.     

值得商榷的聚合物分子量分布宽度指数表达式

认为张晓云在“有关聚合物平均分子量和分子量多分散性的教学点滴”一文中对聚合物分子量分布宽度指数的定义以及由此得出的结论是值得商榷的。本文介绍了具有统计意义的分子量分布宽度指数的定义，比较了四种常用平均分子量的相对大小。     

毛细管内高分子溶液的浓度分布

采用连续自洽场理论分析了毛细管中发生凝胶化之前的聚合物溶液浓度分布的影响因素及其规律. 结果表明, 体系尺寸有限时, 改变聚合物链段、溶剂与壁面的相互作用参数之差, 聚合物溶液浓度分布会发生贫化/吸附转变; 临界作用参数与聚合物链长的倒数呈线性关系, 且拟合常数与体系尺寸、聚合物溶液平均体积分数有关; 聚合物分子量分布为多分散时, 分子量较低的组分更容易接近容器壁面, 分子量较大的组分则相反. 总之, 增加聚合物溶液浓度、链长, 选择优良溶剂, 减小体系尺寸等都会使浓度分布更加均匀.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

解决能源问题的新途径——光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。