Copolymerization of ethylene/propylene elastomer using high-activity Ziegler-Natta catalyst system of MgCl2 (ethoxide type)/EB/PDMS/TiCl4/PMT

2002 ◽  
Vol 84 (4) ◽  
pp. 785-790 ◽  
Author(s):  
G. H. Zohuri ◽  
F. Sadegvandi ◽  
R. JamJah ◽  
S. Ahmadjo ◽  
M. Nekoomanesh ◽  
...  
Keyword(s):  
High Activity ◽  
Catalyst System ◽  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Comparative Polymerization Activity of EPM and EPDM Using VCI4 Homogenous Ziegler-Natta Catalyst and Characterization of EPDM Obtained

2005 ◽  
Vol 78 (4) ◽  
pp. 682-693 ◽  
Author(s):  
G. H. Zohuri ◽  
M. Vakili ◽  
R. Jamjah ◽  
S. Ahmadjo ◽  
M. Nekomanesh
Keyword(s):  
Catalyst System ◽  
Relative Pressure ◽  
Polymerization Time ◽  
Polymer Yield ◽  
Ethylene Propylene ◽  
Good Thermal Stability ◽  
Time Profiles ◽  
Polymerization Behavior ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Abstract Copolymerization of ethylene/propylene (EPM) and terpolymerization of ethylene/propylene/5-ethylidene-2-nor-bornene (ENB) were carried out using VCl4 based Ziegler-Natta catalyst. Triisobutylaluminum (TIBA) was used as a cocatalyst while CHCl3 and CCl4 were used as promoters. Effects of [Al]/[V] ratio, temperature, promoters and ENB concentration, relative pressure of P/E, H2 concentration and polymerization time on polymerization behavior were studied. The highest productivity of the catalyst was obtained at [Al]/[V] ratio of 8–10. Increasing the [Al]/[V] ratio increased Et% and Tg and decreased ENB% of the EPDM (ethylene / propylene / diene) obtained. Activity of the catalyst system was higher for EPM than EPDM. ENB concentration affected polymer yield. Increasing ENB from 5 ml/Lit solvent to 10 ml /Lit solvent increased productivity of the catalyst; however, higher concentration decreased the EPDM polymer yield. Addition of ENB increased Et% of the EPDM. Polymerization of EPDM was carried out at temperatures of 25 °C to 75 °C. The highest productivity was obtained at ∼ 50 °C. At reaction temperature of ∼ 55 °C, Et% and ENB% were 65.5% and 9%, respectively. Rp/time profiles were decay types for both EPM and EPDM production. Et% of EPDM increased with polymerization time, while an inverse result was obtained for ENB%. Addition of CHCl3 to 3 ml /lit solvent increased productivity of the catalyst. However, addition of CCl4 did not have such effect on the yield of the polymer obtained. Effect of relative pressure of P/E=1.25:1 to 0.89:1 on EPDM polymerization was studied. Addition of ethylene relative pressure increased Et% and increased Tg of the EPDM obtained. The lowest Tg of the EPDM obtained was −39 °C. A compound made with the EPDM showed good thermal stability.

scholarly journals EFFECT OF HYDROGEN ON THE CHAIN STRUCTURE OF ETHYLENE-PROPYLENE COPOLYMER SYNTHESIZED BY SUPPORTED HIGH-ACTIVITY ZIEGLER-NATTA CATALYST

2010 ◽  
Vol 006 (4) ◽  
pp. 632-635
Author(s):  
Na LI ◽  
Xiaofeng WANG ◽  
Qi DONG ◽  
Zhisheng FU ◽  
Zhiqiang FAN
Keyword(s):  
High Activity ◽  
Chain Structure ◽  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Influences of silane/ether composite external donors on propylene polymerization with MgCl2-supported Ziegler-Natta catalyst in the presence of hydrogen

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Song-tao Tu ◽  
Jun-qin Lou ◽  
Zhi-sheng Fu ◽  
Zhi-qiang Fan
Keyword(s):  
Molecular Weight ◽  
Catalytic Activity ◽  
High Activity ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Catalyst System ◽  
Propylene Polymerization ◽  
External Donor ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

AbstractIn this work, the effects of two silane type external donors, Ph2Si(OCH3)2 (DPDMS) and dicyclopentyldimethoxysilane (DCPDMS) on propylene slurry polymerization in the presence of hydrogen with a MgCl2/TiCl4/DIBP - Al(C2H5)3 catalyst system were investigated, and the tacticity distribution and molecular weight distribution (MWD) of polypropylene (PP) were further regulated by using silane/ether (ROCH3, R = n-Bu, i-C8H17) composite external donors. The tacticity distribution of PP, as revealed by successive self-nucleation and annealing (SSA) thermo analysis of the polymer, is markedly changed by the external donors. DCPDMS shows much stronger effects than DPDMS. Addition of the ether as an auxiliary external donor in MgCl2/TiCl4/DIBP-TEA/silane (DPDMS or DCPDMS) lead to further increase in catalytic activity and isotacticity of PP, and changes in tacticity distribution. By using the composite external donors, PP with both higher isotacticity index, lower molecular weight or narrower molecular weight distribution was prepared at high activity. Effects of the external donors on the active center distribution were discussed based on the results of deconvoluting the MWD curve with multiple Flory “most-probable” distributions, and possible mechanism of the external donor effects was proposed.

scholarly journals Investigation of a Ziegler–Natta catalyst system derived from a mixture of lithium tetraalkylaluminate, aluminum chloride, and titanium tetrachloride and its usefulness in polymerizations involving styrene

1981 ◽  
Vol 59 (10) ◽  
pp. 1425-1432 ◽  
Author(s):  
Anu Mishra
Keyword(s):  
Aluminum Chloride ◽  
Titanium Tetrachloride ◽  
Active Catalyst ◽  
Catalyst System ◽  
Active Components ◽  
Vinyl Ethers ◽  
Natta Catalyst ◽  
Stereospecific Polymerization ◽  
Derivatives Of ◽  
Ziegler Natta Catalyst

Vinyl ethers, 1-olefins, and styrene were homo- and copolymerized by the use of catalyst derived from a mixture of lithium tetraalkylaluminate (LiAlR4), aluminum chloride (AlCl3), and titanium tetrachloride (TiCl4), in order to determine the nature of the active components present.It is postulated that the active catalyst in the stereospecific polymerization of vinyl ethers is ether-coordinated TiCl3•LiCl, while in the polymerization of 1-olefins and styrene, it is the alkylated derivatives of TiCl3•LiCl.For homo- and copolymerization of styrene, AlR3 seems to be the preferred alkylating agent. About 3 to 4 equivalents of AlR3 are needed for complete alkylation of TiCl3•LiCl, probably due to heterogeneity of the system.Highly isotactic polystyrene and copolymers of styrene with 1-olefins can be prepared in good yields by the use of this catalyst.

Synthesizing UHMWPE Using Ziegler-Natta Catalyst System of MgCl2(ethoxide type)/ TiCl4/tri-isobutylaluminum

2008 ◽  
Vol 274 (1) ◽  
pp. 148-153 ◽  
Author(s):  
Roghieh Jamjah ◽  
Gholam Hossein Zohuri ◽  
Mohsen Javaheri ◽  
Mehdi Nekoomanesh ◽  
Saeid Ahmadjo ◽  
...  
Keyword(s):  
Catalyst System ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Polyethylene Nanocomposites Obtained fromin‐situPolymerization Using Supported Ziegler‐Natta Catalyst System

2007 ◽  
Vol 44 (1) ◽  
pp. 11-15 ◽  
Author(s):  
Fu‐An He ◽  
Li‐Ming Zhang ◽  
Fan Yang ◽  
Li‐Shan Chen ◽  
Qing Wu
Keyword(s):  
Catalyst System ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Ethylene-propylene copolymers by a supported Ziegler-Natta catalyst based on TiCl4/MgCl2

1997 ◽  
Vol 39 (2) ◽  
pp. 133-140 ◽  
Author(s):  
Fernanda M. B. Coutinho ◽  
José Luiz Luna Xavier
Keyword(s):  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst
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