II. The Effect of Polymer Density Fluctuations on Dynamics of High-Molecular-Weight Polymers

1997 ◽  
pp. 77-86
Author(s):  
A. N. Semenov
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Density Fluctuations ◽  
High Molecular Weight Polymers ◽  
Polymer Density

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.

scholarly journals Aqueous Phase Separation Behavior of Highly Syndiotactic, High Molecular Weight Polymers with Densely Packed Hydroxy-Containing Side Groups

2018 ◽  
Vol 51 (18) ◽  
pp. 7248-7256 ◽  
Author(s):  
Dorette S. Tromp ◽  
Marianne Lankelma ◽  
Hannah de Valk ◽  
Emile de Josselin de Jong ◽  
Bas de Bruin
Keyword(s):  
Molecular Weight ◽  
Phase Separation ◽  
High Molecular Weight ◽  
Aqueous Phase ◽  
High Molecular Weight Polymers ◽  
Phase Separation Behavior ◽  
Separation Behavior

Polymerization of Higher α-Olefins with a Bis(Phenoxyimine)Ti Complex/i-Bu3Al/Ph3CB(C6F5)4:  Formation of Stereo- and Regioirregular High Molecular Weight Polymers with High Efficiency

2006 ◽  
Vol 39 (12) ◽  
pp. 4023-4031 ◽  
Author(s):  
Junji Saito ◽  
Yasuhiko Suzuki ◽  
Haruyuki Makio ◽  
Hidetsugu Tanaka ◽  
Mitsuhiko Onda ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Complex I ◽  
High Efficiency ◽  
High Molecular Weight Polymers

Synthesis of New Phosphazene High Molecular Weight Polymers Containing Functionalized and Optically Active Spirocyclic Groups

1998 ◽  
Vol 31 (10) ◽  
pp. 3189-3196 ◽  
Author(s):  
Gabino A. Carriedo ◽  
Francisco J. García Alonso ◽  
Pedro A. González ◽  
José L. García-Alvarez
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Optically Active ◽  
High Molecular Weight Polymers

A model of flocculation by very-high-molecular-weight polymers

1989 ◽  
Vol 267 (6) ◽  
pp. 506-510 ◽  
Author(s):  
A. Molski ◽  
W. Nowicki
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
High Molecular Weight Polymers ◽  
Very High
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