SYNTHESIS OF A POLYETHYLENE-GRAFT-POLYSTYRENE COPOLYMER AND ITS COMPATIBILIZATION FOR LINEAR LOW-DENSITY POLYETHYLENE/POLY(PHENYLENE OXIDE) BLENDS

Based on unsteady diffusion kinetics, polyethylene(PE)-graft-polystyrene (PS) copolymers were designed and synthesized with a heterogeneous high yield titanium-based catalyst by copolymerization of ethylene with a PS-macromonomer using 1-hexene as a short chain agent to promote the incorporation of the PS-macromonomer. The presence of 1-hexene facilitated the diffusion of the PS-macromonomer, giving rise to the significantly increased incorporation of the PS-macromonomer. Compatibilization of blends of linear low density polyethylene (LLDPE)/poly(phenylene oxide) (PPO) with the PE-g-PS copolymer were investigated using scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA).

裂解色谱法测定环化顺1,4聚丁二烯的环化度

用裂解色谱法(PGC)研究了不同环化度的环化顺1,4聚丁二烯(CPBd)。建立了测定CPBd环化度的方法。分析了不同实验条件下生成的CPBd的环化度,结果与NMR测定值一致。

二价铕中性芳烃配合物［Eu（C_6Me_6）（AlCl_4）_2_4·Me_4

首次合成了二价铕中性芳烃配合物［Ｅｕ（Ｃ６Ｍｅ６（ＡｌＣｌ４）２］·Ｍｅ４Ｃ６Ｈ２，并经红外光谱，激发光谱和荧光光谱表征，测定了晶体结构。配合物属单斜晶系，Ｐ２／ｃ空间群，晶胞参数ａ＝１．７６５２（４）ｎｍ，ｂ＝１．５９１８（４）ｎｍ，ｃ＝１．８７５２（５）ｎｍ；β＝９７．６１（５）°，Ｚ＝２，Ｒ＝０．０４９６，Ｒｗ＝０．０４６２。

聚吡咯电化学掺杂过程的拉曼光谱研究

共轭导电聚合物经过掺杂,电导率可以提高十几个数量级,由绝缘体变为导体.但是,掺杂对聚合物链结构的影响方面,人们目前尚所知甚少.从实验的角度看,由于物性测量结果和材料的制备过程密切相关,往往不容易重复,有时还会出现一些令人困惑的假象.电化学现场物性测量技术可以针对同一样品,由电化学方法改变掺杂最,就可

等温熔体结晶尼龙1010的晶体结构

WAXD研究表明,在结晶温度T_c≤196℃时,尼龙1010等温熔体结晶样品的结晶度X_c和微晶尺寸L_(100)随T_c升高近乎线性增大,而氢键面上的相对衍射强度R却降低;T_c>196℃后三者与T_c关系发生相反变化。结晶速率快时有利于分子链在垂直于氢键平面方向上堆砌,反之有利于在平行于氢键平面方向上生长。

常规二脉冲叠加四阶跃微分伏安法研究——可逆电极过程的理论和验证

推导并验证了作者提出的新型阶跃伏安技术——常规二脉冲叠加四阶跃微分伏安法可逆电极过程的理论电流方程,同时研究了各项参数如扫描增量(E_s)、脉冲高度(ΔE)、脉冲周期(T)等对实验的影响,理论与实验结果一致。

SURFACE-MODIFIED HYDROPHILIC MEMBRANES IN MEMBRANE DISTILLATION

The porosity and the hydrophobicity of membranes are two essential requirements for membrane distillation (MD) of aqueous solutions. So far, the hydrophobic porous membranes used in MD studies have been prepared from hydrophobic materials. In this work, hydrophilic cellulose acetate and cellulose nitrate membranes were modified into hydrophobic membranes by radiation grafting polymerization and plasma polymerization, and used in MD studies successfully. The results indicated that modified membranes with good performance in MD can be obtained if the modifying conditions are controlled appropriately. Especially plasma polymerization, in which many particular kinds of monomer could be polymerized onto the surface of porous materials, has become an efficient method to prepare hydrophobic porous membrane with high performance from hydrophilic membranes. It will stimulate the development and practical application of MD.

THERMAL DECOMPOSITIONS OF SOME BIOINORGANIC COMPLEXES OF EUROPIUM

Thermogravimetric and derivative thermogravimetric investigations for three kinds of bioinorganic complexes of europium with N-acetyl-DL-alanine, N-acetyl-DL-valine and DL-alanyl-DL-alanine have been performed. It was found that the water molecules in these solid state complexes are not directly coordinated to the europium ion and that there may be three or four steps in the thermal decomposition process of these complexes after dehydration. The possible thermal decomposition reactions of these bioinorganic complexes have been suggested and discussed.

利用偏振紫外可见光谱研究酞菁铜衍生物在LB膜中的分子取向

制备了三—[4—(2,4—二特戊基苯氧基)]—4—对羧基苯氧基酞菁铜(简写为asyCuPc)LB膜,对比紫外可见光谱及LB膜的偏振紫外可见光谱探讨了该化合物的不同聚集态,结果表明该酞菁铜分子大环平面在LB膜中为倾斜取向.

尼龙1010骤冷退火样品的晶体结构

尼龙1010的晶体结构属三斜晶系.作者最近导出了X射线衍射法(WAXD)测定尼龙1010结晶度的公式,进而考查了等温结晶时结晶温度T_C对结晶度X_C、晶粒尺寸L_(100)和氢键面相对衍射强度R的影响.发现X_C和L_(100)均随T_C升高而增大,达196℃后又减小;而R与T_C的关系则相反,呈线性降低.结晶速率快有利于分子链在垂直于氢键面的(100)晶面生长,但R值却降低了.本文利用WAXD考查了尼龙1010不同骤冷退火条件样品的晶体结构.

稀土催化异戊二烯本体聚合动力学的研究

以Nd(naph)_3-Al(i-Bu)_3-Al_2Et_3Cl_3为催化剂,在-10～5℃下对异戊二烯(Ip)本体聚合的动力学进行了初步研究。发现单体转化率小于5％时,体系呈非稳态聚合;单体转化率大于50％时聚合受扩散控制;体系处于两者间则为稳态聚合。本体聚合的稳态聚合反应速率方程式为:R_p=K_p[Ln]~(196)M_0,计算出Ip本体聚合的表现活化能为69.9kJ/mol。

SYNTHESES OF BIS(TERT-BUTYLCYCLOPENTADIENYL)LANTHANOID CHLORIDE COMPLEXES AND CRYSTAL-STRUCTURES OF BIS(TERT-BUTYLCYCLOPENTADIENYL)CHLORO(BISTETRAHYDROFURAN)-PRASEODYMIUM AND BIS(TERT-BUTYLCYCLOPENTADIENYL)-CHLOROTETRAHYDROFURANYTTERBIUM

Reaction of lanthanoid trichloride with two equivalents of sodium t-butylcyclopentadienide in tetrahydrofuran affords bis(t-butylcyclopentadienyl)lanthanoid chloride complexes (t-BuCp)2LnCl. nTHF (Ln = Pr, Nd, n = 2; Ln = Gd, Yb, n = 1). The compound (t-BuCp)2PrCl.2THF (1) crystallizes from THF in monoclinic space group P2(1)/c with unit cell dimensions a = 15.080(3), b = 8.855(2), c = 21.196(5) angstrom, beta = 110.34(2)degrees, V = 2653.9 angstrom-3 and D(calcd) = 1.41 g/cm3 for Z = 4. The central metal Pr is coordinated to two t-BuCp ring centroids, one chlorine atom and two THF forming a distorted trigonal bipyramid. The crystal of (t-BuCp)2YbCl.THF (2) belongs to the monoclinic crystal system, space group P2(1)/n with a = 7.726(1), b = 12.554(2), c = 23.200(6) angstrom, beta = 97.77(2)degrees, V = 2229.56 angstrom-3, D(calcd) = 1.50 g/cm3 and Z = 4. The t-BuCp ring centroids, the chlorine atom and the oxygen atom of the THF describe a distorted tetrahedron around the central ion of ytterbium.

THE EFFECT OF FILM-FORMING CONDITIONS FOR TAPCUPC LANGMUIR-BLODGETT-FILMS ON MORPHOLOGY AND PROPERTIES

The dependence of morphology and properties on film-forming conditions is described for the symmetrically substituted copper tetra-4-(2, 4-di-t-amylphenoxy) phthalocyanine (tapCuPc) Langmuir-Blodgett (LB) films. The effects of LB film-forming conditions (such as the surface pressure, pH value and the concentrations of spreading solutions) on film quality were studied with the help of a UV-visible spectrophotometer and a transmission electron microscope. Transmission electron microscopy photographs of the surface morphology of tapCuPc LB films show that a smooth and homogeneous surface structure can be obtained under optimum film-forming conditions.

DETERMINATION OF PARAMETERS OF FAST CHEMICAL REACTION OF ALIZARIN RED S BY SPECTROELECTROCHEMICAL METHOD WITH LOPTLC

The rate constant of very fast chemical reaction generally can be measured by electrochemical methods, but can not by the thin layer electrochemical methods because of the influence of diffusion effect. Long optical path length thin layer cell (LOPTLC) with large ratio of electrode area to solution volume can be used to monitor the fist chemical reaction in situ with high sensitivity and accuracy. It enable the adsorption spectra to be measured without the influence of diffusion effect. In the present paper, a fast chemical reaction of Alizarin Red S (ARS) with its oxidative state has been studied. The reaction equilibrium constant (K) under different potentials can be determined by single step potential-absorption spectra in LOPTLC. An equilibrium constant of 7.94 x 10(5) l.mol(-1) for the chemical reaction has been obtained from the plot of lgK vs. (E - E-1(0)'). Rate constant (k) under different potentials can be measured by single step potential-chronoabsorptiometry. A rate constant of 426.6 l.mol(-1).s(-1) for the chemical reaction has been obtained from the plot of lgK vs. (E - E-1(0)') with (E - E-1(0)') = 0.

长光程薄层光谱电化学法测定茜素红S的快速化学反应参数

本文使用长光程薄层光谱电化学方法监测茜素红S的氧化产物与茜素红S形成分子间氢键的快速化学反应.求出该化学反应的热力学平衡常数为7.94×10~5 l.mol~(-1),动力学反应速率常数为426.6L.mol~(-1)·S~(-1),并从不同角度对实验结果进行讨论。