scholarly journals On the Role of Catabolic Enzymes in Biosynthetic Models of Glycogen Molecular Weight Distributions

ACS Omega ◽  
2017 ◽  
Vol 2 (8) ◽  
pp. 5221-5227 ◽  
Author(s):  
Sharif S. Nada ◽  
Robert G. Gilbert
Keyword(s):  
Molecular Weight ◽  
Catabolic Enzymes ◽  
Molecular Weight Distributions ◽  
Weight Distributions

Titanium pyridyl-phosphinimide complexes — Synthesis, structure, and ethylene polymerization catalysis

2006 ◽  
Vol 84 (5) ◽  
pp. 755-761 ◽  
Author(s):  
Chad Beddie ◽  
Pingrong Wei ◽  
Douglas W Stephan
Keyword(s):  
Molecular Weight ◽  
Key Words ◽  
Ethylene Polymerization ◽  
Olefin Polymerization ◽  
Polymerization Catalysts ◽  
Pyridyl Group ◽  
Molecular Weight Distributions ◽  
Polymerization Catalysis ◽  
Weight Distributions

A series of Ti–pyridyl-phosphinimide complexes of the form Cp′TiX2[NPR2(2-CH2Py)] (Cp′ = Cp, Cp*, R = i-Pr, t-Bu, X = Cl, Me) have been prepared and characterized. These complexes generate ethylene polymerization catalysts upon activation with MAO or B(C6F5)3. The resulting polymers exhibit broad molecular weight distributions. The role of the pyridyl group is discussed in light of stoichiometric reactions of CpTiCl2[NPR2(2-CH2Py)] with B(C6F5)3.Key words: phosphinimide complexes, pyridyl-phosphinimides, olefin polymerization.

Molecular Weight Dependence of Relaxation Spectra of Amorphous Polymers in the Rubbery Region. VIII. Comparisons of Experimental Relaxation Spectra of Commercial Synthetic Rubbers with those Estimated from Molecular Weight Distributions

1967 ◽  
Vol 40 (2) ◽  
pp. 484-492 ◽  
Author(s):  
Genichi Yasuda
Keyword(s):  
Molecular Weight ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Mechanical Relaxation ◽  
General Validity ◽  
Relaxation Spectra ◽  
Molecular Weight Distributions ◽  
Synthetic Rubber ◽  
Weight Distributions

Abstract Synthetic rubber of different species, types, and degrees of mastication were used to examine the general validity of the proposed relationship between mechanical relaxation spectra in the rubbery region and molecular weight distribution. Results show that the proposed relationship can be well used to discuss quantitatively the role of molecular weight distribution in the theoretical behavior of a raw rubber while being processed.

The Use of Novel F-RAFT Agents in High Temperature and High Pressure Ethene Polymerization: Can Control be Achieved?

2007 ◽  
Vol 60 (10) ◽  
pp. 788 ◽  
Author(s):  
Markus Busch ◽  
Marion Roth ◽  
Martina H. Stenzel ◽  
Thomas P. Davis ◽  
Christopher Barner-Kowollik
Keyword(s):  
Molecular Weight ◽  
High Pressure ◽  
High Temperature ◽  
Degree Of Polymerization ◽  
Molecular Weight Distributions ◽  
High Pressure High Temperature ◽  
Reversible Addition ◽  
Weight Distributions ◽  
Raft Agent ◽  
Initial Results

Simulations are employed to establish the feasibility of achieving controlled/living ethene polymerizations. Such simulations indicate that reversible addition–fragmentation chain transfer (RAFT) agents carrying a fluorine Z group may be suitable to establish control in high-pressure high-temperature ethene polymerizations. Based on these simulations, specific fluorine (F-RAFT) agents have been designed and tested. The initial results are promising and indicate that it may indeed be possible to achieve molecular weight distributions with a polydispersity being significantly lower than that observed in the conventional free radical process. In our initial trials presented here (using the F-RAFT agent isopropylfluorodithioformate), a correlation between the degree of polymerization and conversion can indeed be observed. Both the lowered polydispersity and the linear correlation between molecular weight and conversion indicate that control may in principle be possible.

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