Limitations in the Synthesis of High Molecular Weight Polymers via Nitroxide-Mediated Controlled Radical Polymerization:  Modeling Studies

2003 ◽  
Vol 36 (20) ◽  
pp. 7812-7823 ◽  
Author(s):  
Todd M. Kruse ◽  
Razima Souleimonova ◽  
Andrew Cho ◽  
Maisha K. Gray ◽  
John M. Torkelson ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Radical Polymerization ◽  
Controlled Radical Polymerization ◽  
High Molecular Weight Polymers ◽  
Modeling Studies

scholarly journals Synthesis of super high molecular weight copolymer of AM/NaA/AMPS by oxidation–reduction and controlled radical polymerization

2019 ◽  
Vol 17 (1) ◽  
pp. 242-254
Author(s):  
Ji Yan-feng ◽  
Cao Xu-long ◽  
Zhu Yang-wen ◽  
Xu Hui ◽  
Sun Xiu-zhi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Radical Polymerization ◽  
Oil Recovery ◽  
Salt Resistance ◽  
Temperature Tolerance ◽  
Controlled Radical Polymerization ◽  
Force Microscopy ◽  
Oxidation Reduction ◽  
Hydrolyzed Polyacrylamide

AbstractSuper high molecular weight copolymers of AM/NaA/AMPS were prepared by oxidation–reduction [OR-P(AM/NaA/AMPS)] and controlled radical polymerization [CR-P(AM/NaA/AMPS)]. The resulting copolymers were fully characterized, and the reaction conditions for their preparation were optimized. OR-P(AM/NaA/AMPS), CR-P(AM/NaA/AMPS), and conventional partially hydrolyzed polyacrylamide (HPAM) in brine solution were comprehensively characterized by thermogravimetric analysis, scanning electron microscopy, atomic force microscopy, and dynamic light scattering. OR-P(AM/NaA/AMPS) and CR-P(AM/NaA/AMPS) containing AMPS monomer showed better salt resistance, temperature tolerance, and viscosification property than the conventional HPAM polymer, making them more promising for enhanced oil recovery. Through comprehensive comparison and analysis, it was found that OR-P(AM/NaA/AMPS) was more conducive for high-temperature condition due to the existence of xanthone in OR-P(AM/NaA/AMPS). On the other hand, CR-P(AM/NaA/AMPS) was more suitable for high-mineral atmosphere, which could be attributed to its higher intrinsic viscosity.

Tertiary amine catalyzed photo-induced controlled radical polymerization of methacrylates

2015 ◽  
Vol 6 (30) ◽  
pp. 5362-5368 ◽  
Author(s):  
Qiang Fu ◽  
Thomas G. McKenzie ◽  
Shereen Tan ◽  
Eunhyung Nam ◽  
Greg G. Qiao
Keyword(s):  
Molecular Weight ◽  
Radical Polymerization ◽  
Uv Irradiation ◽  
Tertiary Amine ◽  
Controlled Radical Polymerization ◽  
Low Molecular Weight ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
End Group

A novel tertiary amine catalyst and trithiocarbonate synergistic photo-induced controlled radical polymerization of methacrylates has been realized under mild UV irradiation, yielding polymethacrylates with low molecular weight distributions and excellent end-group fidelity.

Determination of Peroxides in Synthetic Rubbers

1945 ◽  
Vol 18 (4) ◽  
pp. 874-876
Author(s):  
Richard F. Robey ◽  
Herbert K. Wiese
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Quantitative Determination ◽  
High Molecular Weight ◽  
Active Oxygen ◽  
Lower Molecular Weight ◽  
Synthetic Rubber ◽  
High Molecular Weight Polymers ◽  
Methanol Solutions

Abstract Peroxides are found in synthetic rubbers either as the result of attack by oxygen, usually from the air, or as a residue from polymerization operations employing peroxide catalysts. Because of possible detrimental effects of active oxygen on the properties of the rubber, a method of quantitative determination is needed. The concentration of peroxides in substances of lower molecular weight may be determined with ferrous thiocyanate reagent, either titrimetrically as recommended by Yule and Wilson or colorimetrically as by Young, Vogt, and Nieuwland. Unfortunately, many highly polymeric substances are not soluble in the acetone and methanol solutions employed in these procedures. This is also the case with hydrocarbon monomers, such as butadiene, containing appreciable concentrations of soluble high molecular weight polymers. Bolland, Sundralingam, Sutton and Tristram recommended benzene as a solvent for natural rubber samples and the reagent made up in methanol. However, most synthetic rubbers are not readily soluble even in this combination. The following procedure employs the ferrous thiocyanate reagent in combination with a solvent capable of maintaining considerable concentrations of synthetic rubber in solution. The solvent comprises essentially 20 per cent ethanol in chloroform.

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