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1.
Kaminsky型催化剂化乙烯齐聚:二酚基二茂锆的催化作用   总被引:6,自引:0,他引:6  
王梅  沈玉梅 《分子催化》1999,13(4):282-286
通过改变Al/Zr比,反应温度及反应时间,分别考察了Cp2Zr(OAr)2/EAO(Ar=C6H5、p-C6H4Me、M-c6h4no2、P-c6h4no2)4种体系对乙烯齐聚的催化作用,发现用Cp2Zr(OAr)2代替Cp2ZrCl2作为主催化剂,对于Kaminsky型体系Cp2ZrL2/EAO催化乙烯齐聚,具有调变作用,在提高催化活性的同时,可使低碳烯烃的造反  相似文献   

2.
通过改变 Al/ Zr 比、反应温度及反应时间, 分别考察了 Cp2 Zr( O Ar)2/ E A O ( Ar= C6 H5、p  C6 H4 M e、m  C6 H4 N O2、p  C6 H4 N O2) 4 种体系对乙烯齐聚的催化作用. 发现用 Cp2 Zr( O Ar)2 代替 Cp2 Zr Cl2 作为主催化剂, 对于 Kam insky 型体系 Cp2 Zr L2/ E A O 催化乙烯齐聚, 具有调变作用,在提高催化活性的同时, 可使低碳烯烃的选择性明显改善. 在 Cp2 Zr( O Ar)2/ E A O 的4 种催化体系中, 当酚基对位带有强吸电子基团时( Ar= p  C6 H4 N O2), 对乙烯齐聚的催化性能最佳.  相似文献   

3.
钱明星  黄勇 《分子催化》2000,14(1):29-32
合成了Ind2Zr(OC6H3-3,5-Me)2(A)、Ind2ZrCl(OCyH3-3,5-Me2)(B)和Ind2ArCl2(C)3个化合物,并在不同反应温度、陈化温度、反应时间等条件下,分别考察了每个化合物与Et2AICl所组成的催化体系对乙烯剂聚活笥和选择性的影响。在相同条件下,催化剂活性顺序为A〉B〉C,在最佳反应条件下,Ind2Zr(OC6H3-3,5Me2)2的催化活必来1951g齐  相似文献   

4.
茂金属催化剂 ( Kaminsky催化剂 )是 80年代发展起来的烯烃聚合高效催化剂 [1] ,有关其催化烯烃聚合的研究很多 [2~ 4 ] .近年来 ,Kaminsky型催化剂催化乙烯齐聚合成低碳α烯烃的研究已有报道 [5] .由乙烯齐聚得到的直链低碳α烯烃是生产线性低密度聚乙烯 ( LL DPE)和高密度聚乙烯 ( HDPE)的共聚单体 .以茚基锆化合物与烷基铝组成的 Ziegler- Natta催化体系催化乙烯齐聚尚未见报道 .本文考察了Ind2 Zr( OC6H4 Me- p) 2 和各种乙基铝组成的二元催化体系对乙烯齐聚的催化性能 .1 实验部分  二茚基锆配合物 Ind2 Zr Cl2 和 Ind2 …  相似文献   

5.
锗桥连茚及取代茚配体相继与丁基锂及ZrCl4作用,生成锗桥连茚基及取代茚基锆化合物Me2Ge(2-R1-4-R2-Ind)2ZrCl2[R1=R2=H(1);R1=Me,R2=H(2);R1=Me,R2=Ph(3)].化合物1-3均为内消旋和外消旋异构体的混合物,通过多次重结晶得到化合物1和2的纯外消旋异构体及化合物3的内消旋异构体.由元素分析和1H NMR谱表征了化合物的分子结构.研究了在甲基铝氧烷(MAO)的助催化下,化合物1-3对乙烯和丙烯聚合的催化性能.由锗桥连茚基化合物1-3得到的聚乙烯的分子量分布比一般茂金属催化剂略宽.内消旋和外消旋异构体的混合物(3)由于两个催化活性中心不等同而使得到的聚乙烯的分子量分布相当宽.外消旋异构体1和2催化丙烯聚合得到高等规聚丙烯.  相似文献   

6.
茂金属催化剂(Kaminsky催化剂)是80年代发展起来的烯烃聚合高效催化剂,有关其催化烯烃聚合的研究很多,近年来,Kaminsky型催化剂催化乙烯齐聚合成低碳α烯烃的研究已有报道。由乙烯齐聚得到的直链低碳α烯烃是生产线性低密度聚乙烯(LLDPE)和高密度聚乙烯(HDPE)的共聚单体。以茚基锆化合物与烷基铝组成的Ziegler-Natta催化体系催化乙烯齐聚尚未见报道,本文考察了Ind2Zr(OC6H4Me-p)2和各种乙基铝组成的二元催化体系对乙烯齐聚的催化性能。  相似文献   

7.
rac-Et(Ind)_2ZrCl_2/MAO催化丙烯/1-辛烯共聚合的研究李勇,邴娟松,谢光华(中国科学院化学研究所北京100080)关键词锆茂均相催化体系,丙烯,共聚合乙烯与长链一。烯烃共聚合制备线型低密度聚乙烯(LLDPE)和极低密度聚乙烯(VL...  相似文献   

8.
rac-Et(Ind)_2ZrCl_2/MAO催化丙烯/1-辛烯共聚合的研究李勇,邴娟松,谢光华(中国科学院化学研究所北京100080)关键词锆茂均相催化体系,丙烯,共聚合乙烯与长链一。烯烃共聚合制备线型低密度聚乙烯(LLDPE)和极低密度聚乙烯(VL...  相似文献   

9.
应用XRD、XPS、Mossbauer谱、TPR、CO-TPD、CO+H2反应性能测量试等手段研究了CeO2对F-T合成制低碳烯烃Ce-Fe/ZrO2催化剂催化性能的影响。结果表明,与Fe/Zr催化剂相比,加铈助剂后的催化剂F-T反应催化活性明显上升。  相似文献   

10.
1,3-二(1-茚基)四甲基二硅氧烷相继与丁基锂及ZrCl4.2THF作用,生成硅氧桥联二(1-茚基)二氯化锆(Me2SiOSiMe2)(Ind)2ZrCl2(1)。对其进行催化氢化得到相应的四氢茚基化合物(Me2SiOSiMe2)IndH4)2ZrCl2(2).1和2均含有顺式和反式二种异构体(1和1以及2和2),通过重结晶得到纯的单一异构体,1,2和2,1和2的晶体结构经X射线衍射测定,二者均  相似文献   

11.
Two new hydrazinium lanthanide(III) oxalates, (N2H5)[Nd(C2O4)2(H2O)]·4H2O (1) and (N2H5)[Gd(C2O4)2(H2O)]·4.5H2O (2) have been prepared and their crystal structures determined by single-crystal X-ray diffraction. The crystal structures were solved by the direct methods and Fourier difference techniques, and refined by a least-squares method on the basis of F2 for all unique reflections. Crystallographic data: 1, triclinic, space group , , b=9.762(4), , α=62.378(5), β=76.681(5), γ=73.858(5), Z=2, R1=0.0335 for 172 parameters with 3430 reflections with I?2σ(I); 2, triclinic, space group , , b=9.51(3), , α=62.11(4), β=76.15(5), γ=73.73(5), Z=2, R1=0.0325 for 172 parameters with 1742 reflections with I?2σ(I). The two isotypic structures are built from a three-dimensional (3D) arrangement of lanthanide and oxalate ions. The lanthanide atom is coordinated by eight oxygen atoms from four tetradentate oxalate ions and one aqua oxygen. Alternating lanthanide and oxalate ions form six-membered rings that delimit tunnels running down three directions and occupied by hydrazinium and water molecules. Starting from these lanthanide(III) compounds two isotypic mixed Ln(III)/U(IV) oxalates, (N2H5)0.75[Nd0.75U0.25(C2O4)2(H2O)]·4.5H2O (3) and (N2H5)0.75[Gd0.75U0.25(C2O4)2(H2O)]·4H2O (4), are obtained by partial substitution of Ln(III) by U(IV) in the nine-coordinated site, the charge excess being compensated by removal of monovalent ions from the tunnels. Finally, using Na+ gel, two mixed Ln(III)/U(IV) sodium oxalates, Na0.5[Nd0.5U0.5(C2O4)2(H2O)]·3H2O (5) and Na0.65[Gd0.65U0.35(C2O4)2(H2O)]·4.5H2O (6) have been obtained without any change in the 3D framework.  相似文献   

12.
13.
A new ammonium uranium (IV) oxalate (NH4)2U2(C2O4)5·0.7H2O (1) and three mixed uranium (IV)-lanthanide (III) oxalates, (N2H5)2.6U1.4M0.6(C2O4)5·xH2O (M=Nd (2) and M=Sm (3)), Na2.56U1.44Nd0.56(C2O4)5·7.6H2O (4) and Na3UCe(C2O4)5·10.4H2O (5), have been prepared. The crystal structures of compounds 1, 4 and 5 have been determined by single-crystal X-ray diffraction. The crystal structures were solved by the direct methods and Fourier difference techniques, and refined by a least square method on the basis of F2 for all unique reflections. Compounds 2 and 3 are isotypic with 1. Crystallographic data: 1, hexagonal, space group P63/mmc, a=19.177(3), c=12.728(4) Å, Z=6, R1=0.0575 for 52 parameters with 1360 reflections with I?2σ(I); 2, hexagonal, space group P63/mmc, a=19.243(4), c=12.760(5) Å, Z=6; 3, hexagonal, space group P63/mmc, a=19.211(3), c=12.274(4) Å, Z=6; 4, orthorhombic, space group Pbcn, a=18.79(3), b=11.46(1), c=12.77(2) Å, Z=4, R1=0.0511 for 183 parameters with 3026 reflections with I?2σ(I); 5, monoclinic, space group C2/c, a=18.878(6), b=11.684(4), c=12.932(4) Å, β=95.97(1)°, Z=4, R1=0.0416 for 213 parameters with 4060 reflections with I?2σ(I). The honeycomb-like structure of the five compounds is built from the same three-dimensional arrangement of metallic and oxalate ions. Similar hexagonal rings of alternating metallic and oxalate ions form layers parallel to the (001) plane that are pillared by another oxalate ion. Indeed, some torsions or rotations of the bridging oxalate ligands led to modifications of the network symmetry. The monovalent cations and the water molecules occupy the hexagonal tunnels running down the [001] direction. Starting from the uranium (IV) compound A2U2(C2O4)5·0.7H2O with A=NH4+ (1), the mixed U(IV)/Ln(III) oxalates are obtained by partial substitution of U(IV) by Ln(III) in a ten-coordinated site, the charge deficit being compensated by intercalation of supplementary monovalent ions within the tunnels. The distortion of the arrangement in the [001] direction for the Na-containing compounds allows the accommodation of a greater number of water molecules that insure an octahedral coordination of the Na atoms.  相似文献   

14.
手性二噁唑啉吡啶铁和镍配合物的制备与表征   总被引:1,自引:0,他引:1  
Tridentate bis(oxazolinylpyridine)(1) reacted with nickel chloride or ferrous chloride in anhydrous ethanol to form bis(oxazolinylpyridine) Nickel(Ⅱ) and Iron(Ⅱ) complexes. The stable solid complexes were characterized with IR, UV, MS, XPS and elemental analysis. No stable complexes were formed with bidentate bis(oxazoline)(2) ins- tead of bis(oxazolinylpyridine).  相似文献   

15.
通过原子转移自由基聚合(ATRP)合成了一种带有活性—NH2基团的温度敏感性亲水型共聚物P(NiPAAm-co-DMAA), 并将其作为引发剂, 合成了P(NiPAAm-co-DMAA)-co-P(L-Ala), 其分子量分布(PDI)在1.3左右. 聚合物通过自组装形成纳米胶束. 透射电镜(TEM)结果表明, 胶束大小200~300 nm, 具有明显的核壳结构. 共聚物的最低临界溶解温度(LCST)为45.5 ℃. 温度低于LCST时, 聚合物溶解形成胶束; 高于LCST时, 胶束解离, 聚合物不溶. 聚合物对温度的响应是快速而可逆的.  相似文献   

16.
Abstract

The synthesis of (E)- and (Z)-1.2-bis(p-fluorophenylsulphenyl)stilbenes (2a and 2b) and 1,2-bis(p-fluorophenylsulphonyl)stilbenes (3a and 3b) was carried out and their configurations were consistent with their stereospecific synthesis. The isomeric 1,1-bis(p-fluorophenylsulphenyl)- and 1,1-bis(p-fluorophenylsulphonyl)-2,2-bis(phenyl)ethylenes (8 and 9) were also synthesised and configurations were established by degradative oxidation. Mass spectral rearrangements of all these compounds were examined. Mass spectra of 1,1-bis-sulphide and 1,1-bis-sulphone bears close relationship with those of (E)- and (Z)-isomeric counterparts. Smiles-type rearrangement observed in 1,2-bis-sulphides was absent in 1,2-bis-sulphones. McLafferty-type rearrangement involving hydrogen migration, from aryl group was noticed in both bis-sulphides and bis-sulphones. Vinyl migration to the sulphone oxygen predominates over aryl migration in three isomeric bis-sulphones.  相似文献   

17.
界面缩聚法合成双(烯基环戊二烯基)钛(锆)聚醚的研究   总被引:1,自引:0,他引:1  
本文通过界面缩聚法利用双(烯基环戊二烯基)钛(锆)二氯化物与二酚反应,制成了16个新的高分子化合物,对它们进行了IR、TGA和分子量的测定。文中还对反应条件与分子量的关系进行了讨论。  相似文献   

18.
Reaction of phosphorus trichloride with tert-butanol and fluoroalcohols gave bis(fluoroalkyl) phosphites (RFO)2P(O)H in 42-89% yield, where RF=HCF2CH2, H(CF2)2CH2, H(CF2)4CH2, CF3CH2, C2F5CH2, C3F7CH2, (CF3)2CH, (FCH2)2CH, CF3(CH3)2C, (CF3)2CH3C, CF3CH2CH2, C4F9CH2CH2 and C6F13CH2CH2. Treatment of these with chlorine in dichloromethane gave the bis(fluoroalkyl) phosphorochloridates (RFO)2P(O)Cl in 49-96% yield. The chloridate (CF3CH2O)2P(O)Cl was isolated in much lower yield from the interaction of thionyl chloride with bis(trifluoroethyl) phosphite. Heating the latter in dichloromethane with potassium fluoride and a catalytic amount of trifluoroacetic acid gave the corresponding fluoridate (CF3CH2O)2P(O)F in 84% yield. Treatment of bis(trifluoroethyl) phosphite with bromine or iodine gave the bromidate (CF3CH2O)2P(O)Br and iodidate (CF3CH2O)2P(O)I in 51 and 46% yield, respectively. The iodidate is the first dialkyl phosphoroiodidate to have been isolated and characterised properly—its discovery lags behind the first isolation of a dialkyl phosphorochloridate by over 130 years. The fluoroalkyl phosphoryl compounds are generally more stable than known unfluorinated counterparts.  相似文献   

19.
A simple and effective procedure for the enantioselective synthesis of (R)-and (S)-moprolol was described.The key step was the asymmetric synthesis of enantiopure (R)-and (S)-guaifenesin,which were synthesized from enantioenriched (R)-3-chloro-1,2-propanediol and (S)-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-CoIIII complex.The e.e.values of both the optical compounds were above 98%,and the chemical structures of the target compounds were confirmed by 1H NMR,13C NMR,IR,and MS.  相似文献   

20.
基于铁和锰的双核配合物在生物氧化还原过程中的重要作用及在化学的氧化还原过程中可能做为催化剂的应用前景,本文合成了两个新的以氯醌酸二价阴离子为桥联配体的Fe(Ⅲ)双核和Mn(Ⅱ)双核配合物:[Fe_2(phen)_4(μ-CA)](ClO_4)_4·2H_2O(1)和[Mn_2(phen)_4(μ-CA)](ClO_4)_2·3H_2O(2)(phen=1,10菲咯啉;CA=氯醌酸二价阴离子)。经元素分析、IR、电子光谱及磁性等测定,对两配合物进行了表征。  相似文献   

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