以聚丙二醇二苯甲酸酯为给电子体的丙烯聚合催化剂

 采用聚丙二醇二苯甲酸酯(PPGDB)为内给电子体制备了一种新的丙烯聚合催化剂MgCl2/PPGDB/TiCl4. 该催化剂用于丙烯聚合时,除了具有与以邻苯二甲酸二异丁酯为给电子体的催化剂相当的活性和立体定向性外,其特点在于所得产物的分子量分布较宽(Mw/Mn＞8.0). 采用红外光谱研究了催化剂中PPGDB与MgCl2的作用机制,结果表明PPGDB中的酯官能团和醚官能团可同时与MgCl2配位. 这种双官能团的配位作用是所得聚合物分子量分布较宽的主要原因.     

给电子体在丙烯聚合MgCl2载体催化剂体系中的作用

制备了3种含有不同内给电子体(邻苯二甲酸二异丁酯,9,9-二甲氧基甲基-芴和1,1-双甲氧基甲基-环丁烷)的MgCl2负载型丙烯聚合齐格勒-纳塔(Z-N)催化剂,研究了给电子体结构与聚合性能之间的关系,用红外光谱剖析了催化剂及其相关化合物的结构,结果发现催化剂中的内给电子体直接与MgCl2配位,而没有与TiCl4结合.内给电子体的加入,降低了Z-N催化剂中钛的含量,提高催化丙烯聚合的活性,使聚合物的分子量分布变窄.聚合物立构规整度的变化强烈依赖于内给电子体的结构.     

负载钛系催化剂催化合成高反式丁二烯-异戊二烯共聚物

采用负载钛系催化剂 [TiCl4 MgCl2 (i Bu) 3Al]催化丁二烯 (Bd) 异戊二烯 (Ip)共聚合 ,研究了单体配比、聚合温度、烷基铝浓度和催化剂浓度及单体浓度等对共聚合速率及共聚物特性粘数的影响 .结果表明 ,当单体配比中Bd (Bd +Ip)摩尔百分比≤ 2 0 % ,可制得高分子量的共聚物 .IR光谱分析及1 H NMR分析表明所得共聚物为高反式 1,4 结构 ,丁二烯单体单元的反式 1,4 含量大于 90 % ,异戊二烯单体单元的反式 1,4 含量大于 98% ,共聚物中丁二烯含量高于单体初始配比中的含量 .在一定的载钛量下 ,聚合条件对共聚物的微观结构影响不大     

3-叠氮甲基-3-硝酸酯甲基环氧丁烷的聚合反应研究

改进了单体3-叠氮甲基-3-硝酸酯甲基环氧丁烷的合成路线,以三氟化硼·乙醚为催化剂,1,4-丁二醇为引发剂,研究了该含能单体的开环聚合反应,得到了分子量可预计、分散度较小的聚合物.采用FTIR、¹HNMR和GPC对聚合物结构进行了表征.     

新型Ti-Co复合负载化催化剂制备支化聚乙烯

以反应法制备了TiCl4、乙酰丙酮改性的TiCl4和Co(acac) 2 为主催化剂 ,SiO2 MgCl2 为载体的复合负载型催化剂 (TiCl4 CH3COCH2 COCH3 Co(acac) 2 SiO2 MgCl2 ) ,以烷基铝作为助催化剂 ,以单一乙烯单体制备了支化聚乙烯 .研究了复合催化剂的组成、烷基铝种类和聚合反应温度等对聚合反应和产物结构性能的影响 .探讨了聚合反应机理 .聚合产物经IR、1 3 C NMR谱分析 ,结果表明Ti Co复合催化剂具有低聚原位共聚功能 ,可制得含有丁基、戊基、己基等各类支链结构的支化聚乙烯 .     

极少量1,5-己二烯改善聚丙烯树脂热稳定性研究

在Ziegler-Natta丙烯聚合反应中,引入少量1,5-己二烯,在不明显改变聚丙烯链结构的基础上,通过可能的主链环化,提高其热稳定性.聚合反应由9,9-二(甲氧基甲基)芴为内给电子体的Mg Cl2/Ti Cl4催化剂在本体条件下进行,1,5-己二烯浓度控制在1.0 mol%以下.结果显示,在所控制的1,5-己二烯浓度下,虽然催化剂活性和聚合物分子量有一定程度的降低,但聚合物的熔点(Tm)和熔融焓(ΔHf)只略有下降,而结晶温度(Tc)基本保持不变.GPC和流变测试结果表明聚合物的链结构无变化,聚合过程无支化或交联结构生成.热重分析(TGA)结果显示,聚丙烯热稳定性有较大幅度的提高,初始分解温度(Tonset)从纯聚丙烯的460.6℃提高到482.3℃,聚合物在反应釜中呈良好的颗粒形态.     

非茂钯催化剂催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合的研究

本文探索了乙烯/丙烯/极性单体三元共聚物的合成方法.乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚物由于分子中引入了ω-Cl-α-乙烯基极性单体,改变了乙烯丙烯共聚物的化学惰性.我们采用催化剂Cat.L-Pd配位催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合,合成了极性三元无规共聚物.探讨了催化剂结构、聚合条件对三元共聚合行为的影响,并优化了聚合条件.采用红外光谱(FTIR)、核磁共振碳谱(氢谱)(~(13)C(~1H)NMR)、示差扫描量热(DSC)和高温凝胶渗透色谱(GPC)等方法研究了共聚物的结构与性能.FTIR与~(13)C(~1H)NMR结果表明,催化剂Cat.L-Pd能够有效催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合,共聚物中ω-氯代极性单体的插入量达3.6 mol%.极性单体不发生均聚合反应,但能够有效参与乙烯和丙烯的共聚合反应,形成三元无规共聚物.丙烯能够发生均聚合反应,但是不能形成聚丙烯长链段,主要发生乙烯与丙烯共聚合反应.乙烯最易发生聚合反应,并能够形成较长链段的聚乙烯.共聚物的Mw高于2×10~5g/mol.分子量分布在1.6～3.0,说明该类催化剂催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合行为遵循单中心聚合机理.     

用无外给电子体Ziegler-Natta催化剂催化丙烯聚合的研究

采用 9,9 双 (甲氧基甲基 )芴 (BMMF)为内给电子体合成MgCl2 /TiCl4 /BMMF催化剂 ,以三乙基铝为助催化剂在无需外给电子体的情况下得到高等规度的聚丙烯 .该催化剂具有高活性和高立体定向性 ,并与以邻苯二甲酸二丁酯 (Phthalate)为内给电子体 ,二苯基二甲氧基硅 (DDS)为外给电子体合成的MgCl2 /TiCl4 /Phthalate AlEt3 /DDS催化剂的性能进行比较 ,结果表明无外给电子体催化剂具有较高的活性 ,且聚丙烯的等规度大于 95 % .研究了聚合温度 ,铝钛比等聚合条件对催化剂的活性 ,聚合物的分子量、等规度和熔点的影响 ,并用13 C NMR对聚合物的序列结构进行了分析     

α-二亚胺镍(Ⅱ)配合物-TiCl4复合催化剂催化乙烯原位聚合制备支化聚乙烯

制备了α-二亚胺镍()配合物[C6H5—NC(CH3)—C(CH3)N—C6H5]NiBr2(NiL)-TiCl4负载在MgCl2-SiO2载体上的复合催化剂(NiL-TiCl4/MgCl2-SiO2),以AlR3为助催化剂(不用MAO)催化乙烯聚合.研究了NiL和TiCl4负载方法、NiL/TiCl4摩尔比、助催化剂种类及聚合反应温度等对催化剂性能的影响.用IR和13CNMR表征聚合产物支化度及支链结构;用GC-MS监测聚合反应.实验结果表明,NiL-TiCl4复合催化剂具有齐聚原位共聚特性,可催化乙烯原位聚合,合成支化聚乙烯.     

有机/无机复合载体负载复合催化剂用于乙烯聚合时有机载体的作用

采用溶胶-凝胶法,将苯乙烯-丙烯酸(P(S-co-AA))共聚物包覆在以硅胶/MgCl2为载体的TiCl3催化剂(M-1催化剂)上,负载(n-BuCp)2ZrCl2后制得TiCl3/(n-BuCp)2ZrCl2复合催化剂,研究聚合物载体P(S-co-AA)在复合催化剂乙烯聚合中的作用.前期实验结果表明有机载体P(S-c...     

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.     

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.     

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^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

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。