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1.
环烯烃加成聚合研究开发进展   总被引:7,自引:0,他引:7  
综述了环烯烃加成聚合的催化剂体系及其聚合物的研究和开发状况。主要介绍了催化剂种类,包括传统的齐格勒-纳塔(Ziegler-Natta)催化剂、茂金属催化剂、钯、镍等后过渡金属催化剂,及其催化环烯烃均聚合以及与α-烯烃共聚合的特性,也描述了用不同催化体系进行环烯烃聚合的机理以及环烯烃加成聚合物及其与α-烯烃共聚物的性能及应用前景。  相似文献   

2.
锆茂均相催化体系催化乙烯与降冰片烯共聚合的研究   总被引:3,自引:2,他引:3  
锆茂均相催化体系催化乙烯与降冰片烯共聚合的研究谢光华,王金梅,张盛庆(中国科学院化学研究所,北京,100080)关键词锆茂均相催化体系,乙烯,降冰片烯,共聚合金属二茂基化合物与甲基铝氧烷(MethylalununoxaneMAO)组成以甲苯为溶剂的均...  相似文献   

3.
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   

4.
采用双-(β-酮萘胺)镍(Ⅱ)/B(C6F5)3/AlEt3体系可在20~90 ℃范围内在甲苯溶剂中催化醋酸降冰片烯酯聚合,得到中等分子量(Mw=7.0×103~3.1×104 g/mol)和分子量分布较窄(Mw/Mn为1.8~2.0)的醋酸降冰片烯酯聚合物.采用1H NMR、13C NMR、FT-IR、DSC、TGA及广角X射线衍射(WAXD)等技术对所得聚合物进行了结构表征和性能测试.结果表明,所得的聚醋酸降冰片烯酯为加成型产物,证明此催化体系催化醋酸降冰片烯酯聚合是按乙烯基加成模式进行的;所得聚合产物为非晶态,具有短程有序长程无序的特征,分子链间的距离为1.24 nm;聚合产物具有较好的热稳定性(Td>330 ℃),并能够溶解在大部分普通有机溶剂中.  相似文献   

5.
3种邻-酚羟基取代的N-杂环卡宾[C,O]螯合双配体镍配合物在甲苯中以甲基铝氧烷(MAO)为助催化剂,催化降冰片烯(NBE)聚合.考察了反应温度、时间、n(Al)/n(Ni)以及n(NBE)/n(Ni)等因素对催化活性和所得聚降冰片烯相对分子质量及其分布的影响.结果表明,0℃时催化体系的聚合活性可达,1.34×107gPNBE/(molNi.h);所得聚降冰片烯(PNBE)重均相对分子质量(Mw)可达2.0×106,相对分子质量分布(Mw/Mn)为3.3~1.5,热分解温度在440℃附近,且在室温下可溶于环己烷和三氯苯.通过对聚合产物FTIR,13C-NMR和WAXD分析表明,该聚合反应以烯烃加成聚合方式进行,且聚合物是非晶态结构.  相似文献   

6.
后过渡金属烯烃聚合催化剂研究进展   总被引:5,自引:0,他引:5  
张道  刘长坤  金国新 《分子催化》2002,16(5):390-399
烯烃在催化剂的作用下形成聚合物 .改变催化剂的结构 ,可以得到特定分子结构和特定性能的聚烯烃产物 ,因而催化剂的研究开发是聚烯烃升级换代的核心 .烯烃聚合催化剂的发展大致经历了 3个阶段 :Ziegler- Natta催化剂 -茂金属催化剂 -后过渡金属催化剂 .Ziegler[1]和 Natta[2 ]发现了用于各种 α-烯烃聚合的催化剂 ,并已作为主导技术应用于工业化大生产 . 2 0世纪 80年代初 ,Kaminsky等 [3~ 5] 发现 ,二氯二茂锆与烷基铝氧烷组成的体系(茂金属催化剂 )是一种高催化活性、高立体选择性、长寿命的催化剂 .茂金属催化剂的设计、合成和应用 ,…  相似文献   

7.
双吡唑亚胺镍/甲基铝氧烷催化降冰片烯的聚合   总被引:1,自引:1,他引:0  
合成了两种双吡唑亚胺镍配合物: 双-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.1)和双-4-甲氧基-N-(苯基-1-3,5-二甲基吡唑基亚甲基)苯基亚胺二溴化镍(Cat.2). 研究了Cat.1/MAO和Cat.2/MAO催化体系对降冰片烯(NBE)单体聚合的催化性能, 考察了各种聚合条件, 如温度、Al/Ni摩尔比及催化剂浓度对降冰片烯的催化效率、单体转化率、聚合物分子量及分子量分布的影响. 研究结果表明, Cat.1/MAO和Cat.2/MAO催化体系对降冰片烯聚合具有较高的催化效率, 可达到105 g PNBE/(mol Ni)数量级, 所得聚降冰片烯(PNBE)的重均分子量在105以上, 分子量分布指数在2左右. 聚合产物的1H NMR和FTIR谱分析结果表明, 该聚合反应是以单体的乙烯基加成聚合机理进行的.  相似文献   

8.
双组分茂金属催化剂催化乙烯聚合的研究   总被引:1,自引:0,他引:1  
选择能形成支链的不对称桥联茂金属化合物Me2 C[(Cp) (Ind) ]ZrCl2 和非桥联的不同结构的茂金属化合物二氯二 (烯基取代环戊二烯 )锆如 ( Cp) 2 ZrCl2 ,(Cp) 2 ZrCl2 和 (Cp) 2 ZrCl2 ,以MAO为助催化剂 ,分别组成三组双组分茂金属催化剂的催化体系 ,催化乙烯聚合 .结果表明 ,两类催化剂组成的双组分茂金属催化体系催化乙烯聚合能得到支化的宽分子量分布的聚乙烯 ;聚合温度和改变两种茂金属催化剂的摩尔比对催化活性和分子量有很大影响 .因此可以利用改变双组分茂金属催化剂的摩尔比例和聚合温度来调控聚合物的分子量和分子量分布 .改变两种茂金属催化剂的摩尔比和聚合温度也能使聚合物的结晶度发生改变  相似文献   

9.
采用降冰片烯-5-甲醇和溴丁烷在氢化钠作用下合成了5-丁氧基亚甲基-2-降冰片烯,双-(β-酮萘胺)镍(Ⅱ)/B(C6F5)3催化体系使之聚合。 考察了聚合时间对其均聚合的影响以及5-丁氧基亚甲基-2-降冰片烯和降冰片烯不同摩尔投料比对其共聚行为的影响。 采用1H NMR、FTIR和TGA测试技术对所得的聚合物进行了结构表征和性能测试。 结果表明,双-(β-酮萘胺)镍(Ⅱ)/B(C6F5)3催化体系对5-丁氧基亚甲基-2-降冰片烯均聚和共聚具有较高的催化活性。 得到的均聚物和共聚物为加成型聚合物,料液中5-丁氧基亚甲基-2-降冰片烯的摩尔分数为10%~90%时,其在共聚物中的插入率为22.1%~76.9%,所得聚合物具有较好的热稳定性(Td>360 ℃),在THF和CHCl3等许多普通溶剂中有很好的溶解性能。  相似文献   

10.
β-二酮钛非茂催化剂催化降冰片烯聚合   总被引:1,自引:0,他引:1  
用 (dibenzoylmethanato) 2 Ti(OPh) 2 [(dbm) 2 Ti(OPh) 2 ]/甲基铝氧烷 (MAO)为代表的新型 β 二酮钛非茂催化剂实现了降冰片烯的聚合 ,得到加成聚合和开环易位聚合的混合物 ,研究了实现高聚合活性所需的特殊条件及所得的聚合物结构 ,主要应用傅立叶转变红外技术 (FTIR)对聚合物结构进行了表征和分析  相似文献   

11.
A new class of homogeneous chromium(III)-based catalysts of the type [Cp*CrMeCl]2/MAO with different kinds of Cp ligands has been synthesized. The influence of the electronic nature and the sterical demand of the catalysts were explored with regard to the vinylic polymerization of norbornene. The catalyst activity could be increased by intensifying the electron-donating character of the Cp ligand, whereas the sterical demand of the Cp ligand affects the crystallinity of the obtained polynorbornene. In order to improve their processability, copolymers of norbornene with ethene were made using the [Cp*CrMeCl]2/MAO catalyst, which led to copolymers with a high α-olefin content. Furthermore, highly linear, ultra-high molecular weight polyethylene was obtained using the new class of chromium(III)-based catalysts.  相似文献   

12.
The polymerization of vinyl chloride (VC) with half‐titanocene /methylaluminoxane (MAO) catalysts is investigated. The polymerization of VC with the Cp*Ti(OCH3)3/MAO catalyst (Cp* = η5‐pentamethylcyclopentadienyl) afforded high‐molecular‐weight poly(vinyl chloride) (PVC) in good yields, although the polymerization proceeded at a slow rate. With the Cp*TiCl3/MAO catalyst, the polymer was also obtained, but the polymer yield was lower than that with the Cp*Ti(OCH3)3/MAO catalyst. The polymerization of VC with the Cp*Ti(OCH3)3/MAO catalyst was influenced by the MAO/Ti mole ratio and reaction temperature, and the optimum was observed at the MAO/Ti mole ratio of about 10. The optimum reaction temperature of VC with the Cp*Ti(OCH3)3/MAO catalyst was around 20 °C. The stereoregularity of PVC obtained with the Cp*Ti(OCH3)3/MAO catalyst was different from that obtained with azobisisobutyronitrile, but highly stereoregular PVC could not be synthesized. From the elemental analyses, the 1H and 13C NMR spectra of the polymers, and the analysis of the reduction product from PVC to polyethylene, the polymer obtained with Cp*Ti(OCH3)3/MAO catalyst consisted of only regular head‐to‐tail units without any anomalous structure, whereas the Cp*TiCl3/MAO catalyst gave the PVC‐bearing anomalous units. The polymerization of VC with the Cp*Ti(OCH3)3/MAO catalyst did not inhibit even in the presence of radical inhibitors such as 2,2,6,6,‐tetrametylpiperidine‐1‐oxyl, indicating that the polymerization of VC did not proceed via a radical mechanism. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 248–256, 2003  相似文献   

13.
非MAO的茂钛均相催化体系催化苯乙烯间规聚合———[CpTiMe3]/[Ph3C]+[B(C6F5)4]-催化体系许光学林尚安(中山大学高分子研究所广州510275)关键词茂钛络合物,茂金属催化剂,苯乙烯,间规聚苯乙烯间规聚苯乙烯(sPS)由于具...  相似文献   

14.
对位卤代的苯酚与五甲基茂三氯化钛在三乙胺存在下进行酯化反应 ,制得五甲基茂基三 (对 卤代苯氧基 )钛的 4种新型化合物Cp Ti(O C6 H4 X) 3(X =F ,Cl,Br,I) .用作主催化剂经甲基铝氧烷 (MAO)和三异丁基铝 (TIBA)活化 ,对苯乙烯间规聚合显示出极高的催化活性 ,催化剂热稳定性好 ,制得的聚苯乙烯间规度、分子量和熔点均高 ,在MAO TIBA Ti =4 0 0 2 0 0 1(摩尔比 ) ,温度 6 0℃时 ,10min催化效率可达 3 4 7× 10 6gPS mol·Ti,MAO TIBA Ti=4 0 0 2 0 0 1时茂钛化合物的催化活性几乎是MAO Ti=6 0 0时的 10倍以上 ;4种茂钛催化剂的活性次序Cp Ti(O C6 H4 F) 3 >Cp Ti(O C6 H4 Cl) 3 >Cp Ti(O C6 H4 Br) 3 >Cp Ti(O C6 H4 I) 3 .  相似文献   

15.
By treating cyclodextrin(CD) with methylaluminoxane (MAO such as PMAO or MMAO) or trimethylaluminium (TMA) followed by Cp2ZrCl2, CD/PMAO/Cp2ZrCl2, CD/MMAO/Cp2ZrCl2 and CD/TMA/Cp2ZrCl2 catalysts were prepared. The catalysts were analyzed by 13C-CP/MAS NMR spectrometer and ICP to examine the structure of catalyst and content of Zr and Al. Ethylene polymerization was conducted with MAO or TMA as cocatalyst. Styrene polymerization was also carried out with α-CD/MMAO/Cp*TiCl3 and α-CD/TMA/Cp*TiCl3 catalysts. While the ordinary trialkylaluminium such as TMA as well as MAO can be used as cocatalyst for ethylene polymerization, only MAO could initiate the styrene polymerization with α-CD supported catalysts.  相似文献   

16.
Polymerization of vinyl chloride (VC) with titanium complexes containing Ti‐OPh bond in combination with methylaluminoxane (MAO) catalysts was investigated. Among the titanium complexes examined, Cp*Ti(OPh)3/MAO catalyst (Cp*; pentamethylcyclopentadienyl, Ph; C6H5) gave the highest activity for the polymerization of VC, but the polymerization rate was slow. From the kinetic study on the polymerization of VC with Cp*Ti(OPh)3/MAO catalyst, the relationship between the Mn of the polymer and the polymer yields gave a straight line, and the line passed through the origin. The Mw/Mn values of the polymer gradually decrease as a function of polymer yields, but the Mw/Mn values were somewhat broad. This may be explained by a slow initiation in the polymerization of VC with Cp*Ti(OPh)3/MAO catalyst. The results obtained in this study demonstrate that the molecular weight control of the polymers is possible in the polymerization of VC with the Cp*Ti(OPh)3/MAO catalyst. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3872–3876, 2007  相似文献   

17.
Metallocene catalysts entrapped inside the supercages of NaY zeolite were prepared by reacting NaY with methylaluminoxane (MAO) or trimethylaluminium (TMA) and then with Cp2ZrCl2 (Cp: cyclopentadienyl) or Cp2TiCl2. NaY/MAO/Cp2ZrCl2 and NaY/MAO/Cp2TiCl2 catalysts could polymerize ethylene. The amount of additional MAO for the polymerization was lowered to a mole ratio of Al/Zr of 186. Molecular weights and melting points of polyethylene polymerized with NaY-supported catalysts were higher than those of polyethylene obtained with homogeneous metallocene catalysts. It could be confirmed by extraction experiments that the metallocene catalyst was confined securely inside the supercage of the NaY zeolite.  相似文献   

18.
Titanate(1-) complexes Na[(THF)(kappa1-O-bdbpzp)TiCl4] (1) and Na[(THF)(kappa1-O-bdmpzp)TiCl4] (2) and titanate(2-) complexes [Na(THF)]2[(kappa1-O-bdbpzp)2TiCl4] (4) and [Na(THF)]2[(kappa1-O-bdmpzp)2TiCl4] (5) were obtained in good yield from reaction of Na[bdbpzp] or Na[bdmpzp] (sodium salt of 1,3-bis(3,5-di-tert-butylpyrazol-1yl)propan-2-ol or 1,3-bis(3,5-dimethylpyrazol-1yl)propan-2-ol) with TiCl4 (in the appropriate molar ratio) at 0-25 degrees C. Protonolysis of TiCl4 with 1 equiv of bdmpzpH furnished related zwitterionic titanate(1-) complex 3 that possessed a kappa2-N,O-coordinated pyrazolyl-alkoxide with pendant pyrazolium group. Methylalumoxane (MAO) activation of 1-5 under high-temperature solution polymerization conditions produced active single-site ethylene polymerization catalysts that exhibit considerably higher thermal stability (especially 2/MAO, 3/MAO, and 5/MAO) than previously reported for Cp2TiCl2/MAO or Ti catalysts supported by related heteroscorpionate or scorpionate ligation.  相似文献   

19.
Half-titanocene complexes bearing dibenzhydryl-substituted aryloxide ligands(2a-2d) were prepared. Among them, 2c adopted a three-legged distorted tetrahedral geometry evidenced by X-ray crystallography. The poly-1,3-butadiene with high molecular weight and narrow molecular weight distribution was obtained by using these complexes as the catalysts activated with methylaluminoxane(MAO). The catalytic activities of the complexes depended on their structures. The Ti―O―C bond in the complexes with large angle afforded them with higher activity, while Cp*-based complexes exhibited lower activities than the Cp-based analogues. The activity of complex increased with increasing the polymerization temperature while the selectivity remained no change, indicating the high thermal stability. Furthermore, the polymerization of 1,3-butadiene catalyzed by 2a/MAO at 0 °C has been found in a living fashion.  相似文献   

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