New catalysts for the synthesis of highly reactive polyisobutylene: chloroaluminate imidazole-based ionic liquids in the presence of diisopropyl ether

2016 ◽  
Vol 7 (36) ◽  
pp. 5615-5619 ◽  
Author(s):  
Irina V. Vasilenko ◽  
Ivan A. Berezianko ◽  
Dmitriy I. Shiman ◽  
Sergei V. Kostjuk
Keyword(s):  
Ionic Liquids ◽  
Reaction Temperature ◽  
Monomer Concentration ◽  
Diisopropyl Ether ◽  
Group Content ◽  
High Reaction ◽  
Highly Reactive Polyisobutylene ◽  
End Group

The use of [emim]Cl–AlCl3 in combination with iPr2O allowed the synthesis of HR PIB with high exo-olefin end group content (≥90%) and a relatively narrow MWD (Mw/Mn ≤ 2.0) at a high reaction temperature (>0 °C) and monomer concentration (5.2 M–7.8 M).

scholarly journals Kinetics of radical telomerization of acrylic acid in the presence of 1-octadecanethiol

2018 ◽  
Vol 90 (11) ◽  
pp. 1743-1754 ◽  
Author(s):  
Yaroslav O. Mezhuev ◽  
Oksana Y. Sizova ◽  
Yuri V. Korshak ◽  
Anna L. Luss ◽  
Ivan V. Plyushchii ◽  
...  
Keyword(s):  
Critical Micelle Concentration ◽  
Acrylic Acid ◽  
Monomer Concentration ◽  
Atom Economy ◽  
Exponential Factor ◽  
H Nmr ◽  
Radical Telomerization ◽  
Kinetics Of ◽  
End Group ◽  
C Nmr

AbstractThe oligomer of acrylic acid with a thiooctadecyl end-group was obtained by using octadecyl mercaptan as the chain-transfer agent. The resulting oligomer was characterized by 1H NMR and 13C NMR spectroscopy and critical micelle concentration was determined in aqueous solution. The order with respect to the initiator concentration was 0.5 and 1.6 with respect to the monomer concentration. The abnormal reaction order with respect to the monomer concentration was explained by participation in the chain propagation of unassociated and associated forms of acrylic acid, which were stabilized by formation of hydrogen bonds. The kinetic parameters of telomerization were determined. Telomerization with acrylic acid in the non-associated form had lower activation energy and lower pre-exponential factor than in the case of associated forms. The synthesis of the acrylic acid oligomer with a thiooctadecyl end-group having a low critical micelle concentration in water was carried out in one stage and corresponds to the concept of atom economy.

scholarly journals Heterocyclic bismuth(iii) compounds with transannular N→Bi interactions as catalysts for the oxidation of thiophenol to diphenyldisulfide

2017 ◽  
Vol 7 (22) ◽  
pp. 5343-5353 ◽  
Author(s):  
Ana M. Toma ◽  
Ciprian I. Raţ ◽  
Octavian D. Pavel ◽  
Christopher Hardacre ◽  
Tobias Rüffer ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Reaction Rates ◽  
Total Conversion ◽  
High Reaction ◽  
Diphenyl Disulfide ◽  
Aerial Oxidation

Aerial oxidation of thiophenol to diphenyl disulfide proceeds with high reaction rates, total conversion and selectivity in ionic liquids by using diorganobismuth(iii) catalysts.

Preparation of A Spherical Cellulose Adsorbent as Amino Acid Sorbent

2011 ◽  
Vol 197-198 ◽  
pp. 899-905 ◽  
Author(s):  
Chun Xiang Lin ◽  
Ming Hua Liu ◽  
Huai Yu Zhan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Reaction Time ◽  
Acrylic Acid ◽  
Reaction Temperature ◽  
Monomer Concentration ◽  
Initiator Concentration ◽  
Basic Amino Acids ◽  
Cellulose Adsorbent

The spherical cellulose adsorbent was prepared by grafting acrylic acid onto the spherical cellulose beads prepared by NMMO method. The effecting factors, e.g., monomer concentration, initiator concentration, reaction temperature and reaction time were optimized by the orthogonal and signal-factor experiments and the structure of the adsorbent was characterized by FTIR and SEM. The graft mechanism was also discussed. Moreover, the spherical cellulose adsorbents were shown to behave as good sorbents for basic amino acids L-Arg, L-Lys and L-His.

The Effects of the Reaction Conditions on the Grafting Degree of SiO2-g-PMAA Particle

2012 ◽  
Vol 581-582 ◽  
pp. 301-304
Author(s):  
Ke Hong Zhang ◽  
Hui Xiao ◽  
Jun Juan Du
Keyword(s):  
Silica Gel ◽  
Reaction Temperature ◽  
Methacrylic Acid ◽  
Graft Polymerization ◽  
Monomer Concentration ◽  
Reaction Conditions ◽  
Grafted Polymer ◽  
Limiting Value ◽  
Methacryloxypropyl Trimethoxysilane ◽  
Grafting Degree

Modified MPS-SiO2 particle was obtained by the bonding of 3-methacryloxypropyl trimethoxysilane (KH-570) on the surface of silica gel particle. The methacrylic acid (MMA) monomers were grafted on the surface of MPS-SiO2 particle to prepare the grafting particles SiO2-g-PMAA. The effects of reaction conditions on the graft degree were explored. The results indicate that the MMA monomers can be easily grafted on the surface of silica gel particle by using the method of graft polymerization. During the graft polymerization, the grafted polymer layer is a hindrance to the subsequent graft polymerization. Then the grafting degree of the polymer under a certain condition has a limiting value. The reaction conditions, such as monomer concentration, the amount of initiator, reaction temperature, have remarkably influence on the graft polymerization of SiO2-g-PMAA.

Living free radical polymerization of styrene with 2-cyanoprop-2-yl dithionaphthalate as RAFT agent

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Zhu Jian ◽  
Zhu Xiulin ◽  
Zhou Di ◽  
Chen Jianying
Keyword(s):  
Molecular Weight ◽  
Reaction Temperature ◽  
Raft Polymerization ◽  
Monomer Concentration ◽  
Gel Permeation Chromatography ◽  
Monomer Conversion ◽  
Bulk Polymerization ◽  
Polymerization Rate ◽  
Chain Extension ◽  
Raft Agent

Abstract The reversible addition-fragmentation chain transfer (RAFT) bulk polymerization of styrene was studied using 2-cyanoprop-2-yl dithionaphthalate (CPDN) as RAFT agent in the presence or absence of 2,2’-azoisobutyronitrile (AIBN). The results of both thermally and AIBN-initiated styrene (St) polymerizations show that St can be polymerized in a controlled way using CPDN as RAFT agent; i.e., the polymerization rate is first order with respect to monomer concentration, and molecular weight increases linearly with monomer conversion. The molecular weights obtained from gel permeation chromatography are close to the theoretical values and molecular weight distributions are relatively narrow (Mw/Mn < 1.2). It is confirmed by chain extension reaction that the polymer prepared via RAFT polymerization can be used as a macroRAFT agent. The effects of reaction temperature and mole ratios [St]0/[CPDN]0/[AIBN]0 on the polymerization were investigated. The results indicate that the reaction temperature has a positive effect on the polymerization rate, but little effect on molecular weight and molecular weight distribution, and the optimum mole ratios were found to be [CPDN]0/[AIBN]0 > 4/3 and [St]0/[CPDN]0 < 800.

Catalytic Cracking of Coker Gas Oil at High Reaction Temperature and Catalyst to Oil Ratio

2013 ◽  
Vol 724-725 ◽  
pp. 1112-1115
Author(s):  
Jin Hong Zhang ◽  
Hong Hong Shan ◽  
Chao He Yang ◽  
Xiao Bo Chen ◽  
Chun Yi Li
Keyword(s):  
Nitrogen Content ◽  
Reaction Temperature ◽  
Pilot Scale ◽  
Gas Oil ◽  
Processing Scheme ◽  
Cracking Behavior ◽  
Basic Nitrogen ◽  
High Reaction ◽  
Coker Gas Oil ◽  
The Impact

Coker gas oil (CGO) is difficult to be cracked in the conventional FCC process, due to their high nitrogen content, especially the basic nitrogen compounds. To enhance the conversion of CGO, the high reaction temperature and catalyst to oil ratio processing scheme was performed in a pilot-scale riser FCC apparatus. To study the impact of (basic) nitrogen content, two kinds of CGO were tested. The results show that increasing the reaction temperature and CTO is an effective method for enhancing the conversion of CGO. The (basic) nitrogen content significantly influences the cracking behavior of CGO and the choose of optimal reaction conditions.

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