Stereoregular Polymerization of Butadiene with Alkylaluminum Chlorides and Cobalt Octoate

1966 ◽  
Vol 39 (3) ◽  
pp. 508-520 ◽  
Author(s):  
Morris Gippin
Keyword(s):  
Catalyst System ◽  
Tertiary Alcohol ◽  
Lewis Acidity ◽  
Polar Solvents ◽  
Co Catalyst ◽  
Organic Hydroperoxide ◽  
Butadiene Polymerization ◽  
Chloride Water ◽  
Stereoregular Polymerization ◽  
A Minor

Abstract The requirement of water or oxygen to activate the diethylaluminum chloride co-catalyst used with a cobalt compound to produce 98 per cent cis-1,4 poly-butadiene was reported previously. Activation is considered to form two alkylaluminum compounds differing in Lewis acidity. Several reactions presumed to lead to the formation of the higher acid were carried out with a minor proportion of the diethylaluminum chloride by partial dealkylation with organic hydroperoxide, halogen, tertiary alcohol, organic halide or aluminum. Water is neither necessary nor desirable in the ethylaluminum sesquichloride-cobalt octoate catalyst system. Polar solvents do not appreciably alter the cis-1,4 catalysis with diethylaluminum chloride/water/cobalt octoate, but do decrease the rate or extent of polymerization with increasing dielectric constant of the solvent. A mechanism of cobalt catalysis of butadiene polymerization is proposed.

Development of chiral bisphosphoric acid/Boronic acid Co-catalyst system for enantioselective SN2’ reaction

Tetrahedron ◽  
2021 ◽  
pp. 132412
Author(s):  
Satavisha Kayal ◽  
Jun Kikuchi ◽  
Naoya Shinagawa ◽  
Shigenobu Umemiya ◽  
Masahiro Terada
Keyword(s):  
Boronic Acid ◽  
Catalyst System ◽  
Co Catalyst ◽  
Sn2 Reaction

Butadiene polymerization over a π-allylnickel-alumina-silica gel catalyst system

1980 ◽  
Vol 13 (4) ◽  
pp. 319-322 ◽  
Author(s):  
W. Skupiński ◽  
M. Zawartke ◽  
St. Malinowski
Keyword(s):  
Silica Gel ◽  
Catalyst System ◽  
Butadiene Polymerization

scholarly journals Synthesis of High cis-Polybutadiene in Styrene Solution with Neodymium-Based Catalysts: Towards the Preparation of HIPS and ABS via In Situ Bulk Polymerization

2016 ◽  
Vol 2016 ◽  
pp. 1-11
Author(s):  
Ramón Díaz de León ◽  
Florentino Soriano Corral ◽  
Francisco Javier Enríquez-Medrano ◽  
Gabriela Bosques Ibarra ◽  
Patricia de León Martínez ◽  
...  
Keyword(s):  
Catalyst System ◽  
Bulk Polymerization ◽  
Activation Process ◽  
Morphological Development ◽  
Molecular Weights ◽  
Molar Ratios ◽  
Butadiene Polymerization ◽  
Melting Endotherm ◽  
Synthesized Materials

In a first step, 1,3-butadiene was selectively polymerized at 60°C in styrene as solvent using NdV3/DIBAH/EASC as the catalyst system. The catalyst system activation process, the addition order of monomers and catalyst components, and the molar ratios [Al]/[Nd] and [Cl]/[Nd] were studied. The catalyst system allowed the selective 1,3-butadiene polymerization, reaching conversions between 57.5 and 88.1% with low polystyrene contents in the order of 6.3 to 15.4%. Molecular weights ranging from 39,000 to 150,000 g/mol were obtained, while cis-1,4 content was found in the interval of 94.4 to 96.4%. On the other hand, the glass transition temperatures of synthesized materials were established in the range of −101.9 to −107.4°C, explained by the presence of polystyrene segments in the polybutadiene chains; in the same sense, the polybutadienes did not show the typical melting endotherm of high cis-polybutadienes. In a second step, the resulting styrene/high cis-1,4 polybutadiene solutions were used to synthesize ABS (adding a fraction of acrylonitrile monomer) and HIPS via in situ bulk polymerizations and the results were discussed in terms of morphological development, molecular parameters, dynamical mechanical behavior, and mechanical properties.

Wet air oxidation of pretreatment of pharmaceutical wastewater by Cu2+ and [PxWmOy]q− co-catalyst system

2012 ◽  
Vol 217-218 ◽  
pp. 366-373 ◽  
Author(s):  
Guowen Wang ◽  
Dong Wang ◽  
Xiaochen Xu ◽  
Lifen Liu ◽  
Fenglin Yang
Keyword(s):  
Catalyst System ◽  
Air Oxidation ◽  
Wet Air Oxidation ◽  
Pharmaceutical Wastewater ◽  
Co Catalyst

scholarly journals CoSe2 Clusters as Efficient Co-Catalyst Modified CdS Nanorod for Enhance Visible Light Photocatalytic H2 Evolution

Catalysts ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 616 ◽  
Author(s):  
Ruizhou Gan ◽  
Xiaohua Ma ◽  
Guorong Wang ◽  
Zhiliang Jin
Keyword(s):  
Hydrogen Production ◽  
Noble Metals ◽  
Electron Transition ◽  
H2 Evolution ◽  
Electron Pairs ◽  
Co Catalyst ◽  
Physical Mixing ◽  
A Minor ◽  
Photocatalytic H2 Evolution ◽  
Visible Light Photocatalytic

CoSe2, as a kind of co-catalyst, would replace noble metals element to dope pure CdS. The CoSe2/CdS photocatalyst could be synthesized by simple physical mixing. With the introduction of CoSe2, especially 30% CoSe2/CdS, hydrogen production would be about 500 μmol within 5 h, five times that of pure CdS under the same conditions. The CoSe2/CdS photocatalyst could bear four cycles of hydrogen evolution and sustain the hydrogen production, with a minor decrease. In other words, the electron transition velocity would surge along with the introduction of CoSe2 particles. The CoSe2 could be deemed as the predator and exit of electrons to inspire the detachment of the hole-electron pairs and relieve the recombination of the hole-electron pairs.

Nano-layer based 1T-rich MoS2/g-C3N4 co-catalyst system for enhanced photocatalytic and photoelectrochemical activity

2020 ◽  
Vol 268 ◽  
pp. 118466 ◽  
Author(s):  
Xiaoyi Hu ◽  
Xiangkang Zeng ◽  
Yue Liu ◽  
Jun Lu ◽  
Shi Yuan ◽  
...  
Keyword(s):  
Catalyst System ◽  
Photoelectrochemical Activity ◽  
Co Catalyst

ChemInform Abstract: An Unexpected Bromolactamization of Olefinic Amides Using a Three-Component Co-Catalyst System.

ChemInform ◽  
2016 ◽  
Vol 47 (23) ◽  
Author(s):  
Yi An Cheng ◽  
Wesley Zongrong Yu ◽  
Ying-Yeung Yeung
Keyword(s):  
Catalyst System ◽  
Co Catalyst

Binary molybdenum-based catalyst for coordination polymerization of styrene

2016 ◽  
Vol 49 (5) ◽  
pp. 408-421 ◽  
Author(s):  
Jieting Geng ◽  
Youguo Shao ◽  
Feng Song ◽  
Feng Li ◽  
Jing Hua
Keyword(s):  
Molecular Weight ◽  
Catalyst Activity ◽  
Average Molecular Weight ◽  
Gel Permeation Chromatography ◽  
Catalyst System ◽  
Bulk Polymerization ◽  
Molar Ratio ◽  
Scanning Calorimetry ◽  
Coordination Polymerization ◽  
Co Catalyst

Coordination polymerization of styrene (St) using molybdenum pentachloride supported by phosphite ligand in the presence of metal organic compound was studied for the first time. The types of phosphite and co-catalysts significantly affected the catalytic activity of the molybdenum (V) (Mo(V)) active center and the number-average molecular weight ( Mn) of the resultant polymer. Among the examined catalysts, tri(nonylphenyl)phosphite (TNPP) ligand and AlOPhCH3( i-Bu)2 as co-catalyst provided the polymer with highest yield (up to 87.1%), metallocene as co-catalyst provided the polymer with highest Mn (up to 5.32 × 105). The effect of [P]/[Mo] molar ratio on catalyst activity of the polymerization was discussed and the structures of Mo·TNPP complexes were preliminarily studied by infrared (IR) and ultraviolet spectroscopies. Besides, the polystyrene (PS) samples synthesized through bulk polymerization and solution polymerization were characterized by gel permeation chromatography, IR, carbon 13 nuclear magnetic resonance, and differential scanning calorimetry, respectively, and the results indicated both of the PS had high molecular weight (approximately 105) and atactic structure. All these results demonstrated that Mo(V) catalyst system was very effective for St polymerization.

Sign in / Sign up

Export Citation Format

Share Document