苯乙烯－乙烯共聚物的合成及其结构性能的研究

用负载型钛系催化剂ＭｇＣｌ_２／ＴｉＣｌ_４，ＮｄＣｌ_３／ＡｌＥｔ_３（ＳＮ－１催化剂）制备出组份比例变化的苯乙烯－乙烯共聚产物．共聚产物通过溶剂萃取分离、~１３Ｃ－ＮＭＲ、ＩＲ、动态粘弹谱进行表征，并初步进行了与聚苯乙烯（ａＰＳ）共混作用的研究．结果表明，ＳＮ－１催化剂能有效地催化苯乙烯与乙烯共聚合．共聚产物为含有均聚聚苯乙烯的共聚物复合物，其中的２５ｍｏｌ％的苯乙烯参加了共聚．共聚产物与ａＰＳ共混可明显提高ａＰＳ的冲击强度和断裂伸长率．     

苯乙烯－乙烯共聚物的合成及其结构性能的研究

用负载型钛系催化剂ＭｇＣｌ２／ＴｉＣｌ４，ＮｄＣｌ３／ＡｌＥｔ３（ＳＮ－１催化剂）制备出组份比例变化的苯乙烯－乙烯共聚产物，共聚产物通过溶剂萃取分离，＾１３Ｃ－ＮＭＲ，ＩＲ，动态粘弹谱进行表征，并初步进行了与聚苯乙烯共混作用的研究。结果表明，ＳＮ－１催化剂能有效地催化苯乙烯与乙烯共聚合，共聚产物为含有均聚聚苯乙烯的共聚复合物，其中约２５ｍｏｌ％的苯乙烯参加了共聚。共聚产物与ａＰＳ共混可明显提高ａＰ     

TiCl_4／SiO_2－MgCl_2载体催化剂下的乙烯／己烯－1共聚反应

ＴｉＣｌ_４／ＳｉＯ_２－ＭｇＣｌ_２载体催化剂下的乙烯／己烯－１共聚反应陈辉，张学全，黄葆同王展望，杨永然（中国科学院长春应用化学研究所长春１３００２２）（辽阳化纤公司化工三厂辽阳）关键词乙烯，己烯，共聚，Ｚｉｅｇｌｅｒ－Ｎａｔｔａ催化剂乙烯／α－烯?..     

茂金属催化乙烯与降冰片烯共聚合研究

研究了茂金属催化体系Ｍｅ２ＳｉＣｐ２ＭＣｌ２／ＭＡＯ（Ｍ＝Ｚｒ，ｔｉ）催化乙烯与降冰片烯共聚合，考察了不同聚合条件下的共聚及乙烯动力学行为，对共聚物的结构进行了ＤＳＣ，１３Ｃ ＮＭＲ表征．研究表明，在相同的聚合条件下，Ｚｒ较Ｔｉ有更佳的共聚合催化性能．在相近的投料比条件下，得到了降冰片烯含量和Ｔｇ均较文献高的乙烯与降冰片烯的共聚物．     

新型高活性催化剂乙烯气相聚合的研究（Ⅵ）：锌化合物对催化…

研究了新型高活性乙烯气相聚合催化剂ＴｉＣｌ４、Ｔｉ（ＯＢｕ）４／ＭｇＣｌ２、ＳｉＯ２和ＺｎＣｌ２／醇／ＡｌＲ３体系中ＺｎＣｌ２－ＡｌＥｔ３／ＳｉＯ２重量比和锌化合物含量对气相均聚合的影响，比较了２种不同催化剂Ｃａｔ＃Ａ和Ｃａｔ＃Ｂ的聚合反应力学及性能差异。ｄ ｆ ｃｌｔｉｐ     

新型高活性催化剂乙烯气相聚合的研究（I）：气相均聚和共聚…

研究了新型高活性乙烯气相聚合催化剂ＴｉＣｌ４／ＭｇＣｌ２／ＺｎＣｌ２／ＳｉＣｌ４／醇／Ａｌ（ｉ－Ｂｕ）３体系中钛和醇组分含量对聚合反应和产物颗粒形态的影响。测定了乙烯气相聚合反应动力学曲线，确定了聚合动力学方程。用ＳＥＭ，ＤＳＣ，ＷＡＸＤ，＾１＾３ＣＮＭＲ对催化剂及聚合物的形态，结构和性能进行了分析和表征。     

钛系Ziegler—Natta催化剂下的丙烯α—烯烃的共聚合

研究了ＴｉＣｌ４／ＭｇＣｌ２－三乙基铝高效载体催化体系下的丙烯／癸烯－１共聚及δ－ＴｉＣｌ３－氯二乙基铝催化体上的丙烯／辛烯－１共聚合的基本反应规律，考察了铝钛比、温度、共聚单浓度等对共聚合的影响，对比了两种催化体系的不同，利用非均相Ｚｉｅｇｌｅｒ－Ｎａｔｔｚ催化体系下共聚合的非稳态扩散动力学的观点，解释了观察到的共聚合催化效率增加，共聚物粒子增大等实验现象。     

新型五甲基茂基三苄氧基钛/甲基铝氧烷催化剂合成苯乙烯-乙烯共聚物及其表征

以五甲基茂基三苄氧基钛［Ｃｐ＊ Ｔｉ（ＯＢｚ）３］ 和甲基铝氧烷（ ＭＡＯ） 组成的催化体用本体法合成出苯乙烯 乙烯共聚物Ｐｏｌｙ（Ｓ ｃｏ Ｅ） ．考察了共聚温度,共聚时间,Ａｌ／Ｔｉ 摩尔比,主催化剂浓度［Ｔｉ］ 等条件对共聚反应的影响．共聚产物经沸丁酮,沸四氢呋喃（ＴＨＦ） 连续抽提分离,发现共聚物主要存在于ＴＨＦ 可溶级分中．可溶级分经ＤＳＣ,１３Ｃ ＮＭＲ,ＷＡＸＤ,ＤＭＡ 等手段分析,证明苯乙烯 乙烯共聚物为具有单一玻璃化转变温度（ Ｔｇ） 无熔融温度的无规共聚物,显示弹性体的粘弹性行为．     

新型高活性催化剂乙烯气相聚合的研究（Ⅱ）——改性剂,预聚…

研究了新型高活性乙烯气相聚合催化剂ＴｉＣｌ４／ＭｇＣｌ２／ＺｎＣｌ２／ＳｉＣｌ４醇／Ａｌ（ｉ－Ｂｕ）３体系中不同醇、不同Ｃ２Ｈ５ＯＨ／Ｔｉ摩尔比和正丁醚对聚合反庆及产物颗粒形态的影响，研究了预聚合反应及乙烯气相聚合反应规律，用扫描电镜和图象分析对催化剂、预聚物和聚合产物的形态和颗粒分布的研究表明：新型高活性催化剂和经预聚合制得的乙烯气相聚合物的颗粒形态类似球形，颗粒长短轴比值和大小粒径比值相近。     

钛系Ziegler－Natta催化剂下的丙烯／α－烯烃的共聚合

研究了ＴｉＣｌ＿４／ＭｇＣｌ＿２－三乙基铝（ＴＥＡ）高效载体催化体系下的丙烯／癸烯－１共聚及δ－ＴｉＣｌ＿３－－氯二乙基铝（ＤＥＡＣ）催化体系下的丙烯／辛烯－１共聚合的基本反应规律，考察了铝钛比、温度、共聚单体浓度等对共聚合的影响；对比了两种催化体系的不同，利用非均相Ｚｉｅｇｌｅｒ－Ｎａｔｔａ催化体系下共聚合的非稳态扩散动力学的观点，解释了观察到的共聚合催化效率增加，共聚物粒子增大等实验现象．     

新型高效催化剂乙烯/1-丁烯气相齐聚和共聚制备弹性体及其结构与性能关系

用新型催化体系TiCl₄,Ti(OBu)₄/MgCl₂,SiO₂和ZnCl₂/醇/AlR₃催化乙烯与1-丁烯气相均聚及共聚,制得两种共聚物弹性体,发现新型催化剂体系具有独特的齐聚和原位共聚性能.采用¹³CNMR测定了共聚物链序列分布结构,观察到共聚单体在聚合物链中分布不均匀,存在较长的乙烯链段和较多的1-丁烯嵌段.产物DSC谱图表现出复杂的结晶熔融行为,存在多种结晶形态,出现熔融肩峰及双峰,与通常制得的LLDPE的结晶熔融行为有很大差别;结晶度和密度较低,并具有弹性体性质.     

Structure and Mechanical Properties of Ethylene-butene Copolymers

IntroductionThe studies on synthesizing ethylene- butenecopolymershavebeen oneofthemostattracting sub-jects[1,2 ] .A novel ethylene- butene copolymer elas-tomer was synthesized from gas phase polymeriza-tion in ourlaboratory in thepresenceofa new highlyactive catalyst Ti Cl4 ,Ti(OBu) 4/ Mg Cl2 ,Si O2 or Zn-Cl2 / alcohol/ Al R3 ,which has the properties ofoligamerization and copolymerization in site to cat-alyze the gas phase polymerization of ethylene andbutene[3 ] .This kind of copolymer…     

Melting behavior of polyethylene/α‐olefin copolymers: Narrow composition distribution copolymers and fractions from Ziegler–Natta and single‐site catalyst products

The melting temperature and heat of fusion were measured for an extensive series of compositionally uniform copolymers of ethylene with butene‐1, hexene‐1, and octene‐1. Fractions and whole polymers that exhibited minimal interchain compositional heterogeneity were from commercial copolymers made with either Ziegler–Natta (ZN) or single‐site metallocene catalysts. The present results do not support recent claims that ZN and corresponding metallocene catalyst copolymers melt at significantly different temperatures, nor the implication that comonomer incorporation is “blocky” in ZN copolymers. In five of the six comonomer/catalyst systems the dependencies of the melting temperature on comonomer type and amount were scarcely distinguishable. This common behavior is the same as that for a model random copolymer, so we conclude that most ethylene/α‐olefin copolymers have random distributions of ethylene sequences. The exception in the present study is a metallocene ethylene/butene‐1 copolymer that melts at lower temperatures and apparently has perceptibly alternating sequence distributions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3416–3427, 2004     

The influence of comonomer on ethylene/α-olefin copolymers prepared using [bis(N-(3-tert butylsalicylidene)anilinato)] titanium (IV) dichloride complex

We describe the synthesis of [bis(N-(3-tert-butylsalicylidene)anilinato)] titanium (IV) dichloride (Ti-FI complex) and examine the effects of comonomer (feed concentration and type) on its catalytic performance and properties of the resulting polymers. Ethylene/1-hexene and ethylene/1-octene copolymers were prepared through copolymerization using Ti-FI catalyst, activated by MAO cocatalyst at 323 K and 50 psi ethylene pressure at various initial comonomer concentrations. The obtained copolymers were characterized by DSC, GPC and 13C-NMR. The results indicate that Ti-FI complex performs as a high potential catalyst, as evidenced by high activity and high molecular weight and uniform molecular weight distribution of its products. Nevertheless, the bulky structure of FI catalyst seems to hinder the insertion of α-olefin comonomer, contributing to the pretty low comonomer incorporation into the polymer chain. The catalytic activity was enhanced with the comonomer feed concentration, but the molecular weight and melting temperature decreased. By comparison both sets of catalytic systems, namely ethylene/1-hexene and ethylene/1-octene copolymerization, the first one afforded better activity by reason of easier insertion of short chain comonomer. Although 1-hexene copolymers also exhibited higher molecular weight than 1-octene, no significant difference in both melting temperature and crystallinity can be noticed between these comonomers.     

Preparation of ethylene/α-olefins copolymers using (2-RInd)2ZrCl2/MCM-41 (R:Ph,H) catalyst,microstructural study

(2-RInd)₂ZrCl₂ (R:Ph,H) catalyst was supported on MCM-41 and ethylene copolymerization behavior as well as microstructure of copolymers were studied. A steady rate–time profile behavior was observed for homo and copolymerization of ethylene using supported catalysts. It was noticed that increasing the comonomer content can result in lower physical properties. The obtained results indicated that (2-PhInd)₂ZrCl₂/MCM-41 had higher ability of comonomer incorporation than the non-substituted supported catalysts. The CCC, CCE, and ECC (C: comonomer, E: ethylene) triad sequence distribution in backbone of copolymers were negligible, that means no evidence could be detected for comonomer blocks. The polymer characterization revealed that utilizing 1-octene instead of 1-hexene as the comonomer leads to more heterogeneous distribution of chemical composition. The heterogeneity of the chemical composition distribution and the physical properties were influenced by the type of comonomer and catalyst. (2-PhInd)₂ZrCl₂/MCM-41 produced copolymers containing narrower distribution of lamellae (0.3–1 nm) than the copolymer produce using Ind₂ZrCl₂/MCM-41 (0.3–1.6 nm).     

Spatially inhomogeneous crystallinity in heterogeneous ethylene‐α‐olefin copolymers

The crystallinity development in heterogeneous ethylene‐1‐butene copolymers is compared with that in ethylene copolymers, with more bulky 1‐heptene as a comonomer. The thermal transitions of the 1‐heptene based copolymers persistently occur at higher temperatures than of the corresponding 1‐butene copolymers. The earlier crystallization onset is reflected in thicker primary crystals, which in turn are associated with the presence of longer ethylene sequences because of the inaccessibility of 1‐heptene to sterically shielded catalytic sites. In addition, the 1‐heptene based copolymers are characterized by a higher degree of primary crystallinity, whereas the 1‐butene copolymers exhibit more prominent secondary crystallization. The 1‐butene based copolymers thus have a less heterogeneous chemical composition distribution. At high comonomer contents, the highly heterogeneous nature of the 1‐heptene copolymers is emphasized by a more pronounced presence of low crystalline spherulite inclusions accomplished by the liquid–liquid phase separation of dissimilar polymeric chains before crystallization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3000–3018, 2005     

Copolymerization of 2‐butene and ethylene with catalysts based on titanium and zirconium complexes

The polymerization of 2‐butene and its copolymerization with ethylene have been investigated using four kinds of dichlorobis(β‐diketonato)titanium complexes, [ArN(CH₂)₃NAr]TiCl₂ (Ar = 2,6‐ⁱPr₂C₆H₃) and typical metallocene catalysts. The obtained copolymers display lower melting points than those produced of homopolyethylene under the same polymerization conditions. ¹³C NMR analysis indicates that 9.3 mol‐% of 2‐butene units were incorporated into the polymer chains with Ti(BFA)₂Cl₂‐MAO as the catalyst system. With the trans‐2‐butene a higher copolymerization rate was observed than with cis‐2‐butene. A highly regioselective catalyst system for propene polymerization, [ArN(CH₂)₃NAr]TiCl₂ complex using a mixture of triisobutylaluminium and Ph₃CB(C₆F₅)₄ as cocatalyst, was found to copolymerize a mixture of 1‐butene and trans‐2‐butene with ethylene up to 3.1 mol‐%. Monomer isomerization‐polymerization proceeds with typical metallocene catalysts to produce copolymers consisting of ethylene and 1‐butene.     

负载型钴二亚胺配合物-TiCl_4复合催化剂制备新型乙烯/1-丁烯共聚产物结构性能研究

合成了三种负载型二亚胺配体钴配合物 TiCl4复合催化剂 (CL1、CL2、CL3催化剂 ) .不用MAO ,以烷基铝为助催化剂 ,用它们催化乙烯 1 丁烯淤浆共聚合制备一系列塑性体和弹性体共聚物 .研究表明 ,复合催化剂性质受二亚胺配体性质影响 ,配体L1制备的复合催化剂具有低聚及原位共聚性能 ,可制得高支化度(36 0～ 6 1 5branchnumber 10 0 0C)低密度和极低密度 (0 885～ 0 910g cm3)塑性体和弹性体共聚物 .在 1 丁烯用量低于 5 %时 ,CL1催化剂制备的共聚产物中 1 丁烯含量超过投料比     

Microstructure characterization of short-chain branching polyethylene with differential scanning calorimetry and successive selfnucleation/annealing thermal fractionation

A series of the copolymers of ethylene with 1-hexene(M1–M9) synthesized by metallocene catalyst Et[Ind]2ZrCl2/MAO was studied by differential scanning calorimetry and successive self-nucleation and annealing(SSA) thermal fractionation. The distribution of methylene sequence length(MSL) in the different copolymers was determined using the SSA method. The comonomer contents of samples M4 and M5 are 2.04 mol% and 2.78 mol%, respectively. Both M4 and M5 have low comonomer content and their MSL distribution profiles exhibit a monotonous increase trend with their MSL. The longest MSL of M5 is 167, and its corresponding molar percent is 43.95%, which is higher than that of M4. Moreover, the melting temperature(Tm) of M5 is also higher than that of M4. The comonomer contents of samples M7, M8, and M9 are 8.73 mol%, 14.18 mol% and 15.05 mol%, respectively. M7, M8, and M9 have high comonomer contents, and their MSL distribution profiles display unimodality. M7 has a lower peak value of 33 and a narrow MSL distribution, resulting in a Tm lower than that of M8 and M9. The MSL and its distribution are also key points that influence the melting behavior of copolymers. Sometimes, MSL and its distribution of copolymers have a greater impact on it than the total comonomer contents, which is different from traditional views.     

Ethylene copolymerization with cyclic dienes using rac‐Et[Ind]2ZrCl2–Methylaluminoxane

The effect of the copolymerization temperature and amount of comonomer in the copolymerization of ethylene with 1,3‐cyclopentadiene, dicyclopentadiene, and 4‐vinyl‐1‐cyclohexene and the rac‐Et[Ind]₂ZrCl₂–methylaluminoxane metallocene system was studied. The amount of comonomer present in the reaction media influenced the catalytic activity. Dicyclopentadiene was the most reactive comonomer among the cyclic dienes studied. In general, copolymers synthesized at 60 °C showed higher catalytic activities. Ethylene–dicyclopentadiene copolymers with high comonomer contents (>9%) did not show melting temperatures. 1,3‐Cyclopentadiene dimerized into dicyclopentadiene during the copolymerization, giving a terpolymer of ethylene, cyclopentadiene, and dicyclopentadiene. A complete characterization of the products was carried out with ¹H NMR, ¹³C NMR, heteronuclear chemical shift correlation, differential scanning calorimetry, and gel permeation chromatography. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 471–485, 2002; DOI 10.1002/pola.10133