Thermoreversible cross-linking of ethylene/propylene copolymer rubbers

2017 ◽  
Vol 8 (31) ◽  
pp. 4494-4502 ◽  
Author(s):  
Aihui Wang ◽  
Hui Niu ◽  
Zongke He ◽  
Yang Li
Keyword(s):  
Cross Linking ◽  
Ethylene Propylene ◽  
Synthetic Rubber ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

A functional olefin comonomer containing furan group was designed and implemented in ethylene/propylene copolymerization catalyzed by a traditional Ziegler–Natta catalyst; thus, controllable design of EP rubber with thermoreversible cross-linking capability was realized in a facile way, making the recycle of synthetic rubber more feasible.

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

Synthesis of ethylene-propylene-diene terpolymers with supported Ziegler-Natta catalyst

1993 ◽  
Vol 31 (3) ◽  
pp. 271-278 ◽  
Author(s):  
M. F. V. Marques ◽  
F. M. B. Coutinho
Keyword(s):  
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.

Responses of a Supported Ziegler–Natta Catalyst to Comonomer Feed Ratios in Ethylene–Propylene Copolymerization: Differentiation of Active Centers with Different Catalytic Features

2021 ◽  
Vol 60 (12) ◽  
pp. 4575-4588
Author(s):  
Biao Zhang ◽  
Qingyun Qian ◽  
Pengjia Yang ◽  
Baiyu Jiang ◽  
Zhisheng Fu ◽  
...  
Keyword(s):  
Active Centers ◽  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

Origin of Chemical Composition of Ethylene/Propylene Copolymer Produced with Ziegler-Natta Catalyst

2016 ◽  
Vol 11 (1) ◽  
pp. 1600038 ◽  
Author(s):  
Shougo Takahashi ◽  
Toru Wada ◽  
Patchanee Chammingkwan ◽  
Toshiaki Taniike ◽  
Minoru Terano
Keyword(s):  
Chemical Composition ◽  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

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

Properties of ethylene-propylene copolymers synthesized by a supported Ziegler-Natta catalyst based on TiCl4/MgCl2/PCl3

1997 ◽  
Vol 33 (6) ◽  
pp. 897-901 ◽  
Author(s):  
Fernanda M.B. Coutinho ◽  
JoséLuiz Luna Xavier
Keyword(s):  
Ethylene Propylene ◽  
Natta Catalyst ◽  
Ziegler Natta Catalyst

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

A New Class of Ethylene—Propylene—Diene Terpolymers Produced from Constrained Geometry Metallocene Catalysts

2001 ◽  
Vol 74 (4) ◽  
pp. 688-700 ◽  
Author(s):  
Kim L. Walton ◽  
Morgan M. Hughes ◽  
Deepak R. Parikh
Keyword(s):  
Catalyst Activity ◽  
Barrier Properties ◽  
Unique Combination ◽  
Process Technology ◽  
Ethylene Propylene ◽  
Green Strength ◽  
Constrained Geometry ◽  
Natta Catalyst ◽  
Catalyst Systems ◽  
Ziegler Natta Catalyst

Abstract Until recently, ethylene/propylene/diene (EPDM) terpolymers have been manufactured exclusively using vanadium based Ziegler—Natta catalyst systems. The vanadium based catalysts are known to have both product and process limitations. These limitations are due to a complex combination of factors including monomer reactivity, catalyst activity, reactor temperatures and pressures. Single-site metallocene constrained geometry catalyst (CGC) technology enables the manufacture of EPDM terpolymers at higher reactor temperature and catalyst efficiency than standard Ziegler—Natta catalyst systems. The unique combination of monomer, catalyst and process technology enables the manufacture of highly crystalline EPDMs having ethylene contents over 90 wt %. This study investigated these new highly crystalline EPDM terpolymers and their differentiation from commercially available EPDMs. The results indicated that these new EPDMs had very high green strength and barrier properties, yet could be cured by conventional vulcanization techniques. The cure response of these EPDMs to either peroxide or sulfur increased with increasing ethylene content. Sulfur cured vulcanizates had much higher tensile strength than peroxide cured vulcanizates. These new EPDMs demonstrated utility as additives to enhance the abrasion, hot tear, and tensile properties of natural rubber compounds. Sponge compounds, having the unique combination of polyethylene physical properties and the utility of sulfur vulcanization were developed from these new polymers.

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