Functionalized Polymers by Noncatalytic Addition−Fragmentation Chain Transfer:  Modeling and Simulation of End-Group Functionality and Molecular Weight Distribution for High-Conversion Reactions in a Batch Process

1998 ◽  
Vol 31 (10) ◽  
pp. 3239-3246 ◽  
Author(s):  
W. K. Busfield ◽  
Ilyas Dawood ◽  
A. F. Johnson
Keyword(s):  
Molecular Weight ◽  
Modeling And Simulation ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Chain Transfer ◽  
Batch Process ◽  
Functionalized Polymers ◽  
High Conversion ◽  
End Group

Effect of chain transfer with fracture on the molecular weight distribution of polymers and oligomers

1965 ◽  
Vol 7 (10) ◽  
pp. 2015-2020 ◽  
Author(s):  
V.V. Ivanov ◽  
A.A. Shaginyan ◽  
V.P. Volkov ◽  
N.S. Yenikolopyan
Keyword(s):  
Molecular Weight ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Chain Transfer

The polymerization of styrene by sulphuric acid - III. The molecular weight distribution

1961 ◽  
Vol 263 (1312) ◽  
pp. 75-81 ◽  
Keyword(s):  
Molecular Weight ◽  
Sulphuric Acid ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
High Conversion ◽  
Chain Growth ◽  
Characteristic Parameters ◽  
Relative Probability ◽  
Probable Distribution ◽  
Most Probable Distribution

The theory of the molecular weight distribution in polystyrenes initiated by sulphuric acid, described in part I, has been tested by preparation and fractionation of suitable low-yield polymer samples. The expected ‘most probable’ distribution is found in these samples, but not in a high-conversion polymer. The characteristic parameters of the distributions the relative probability of chain growth—agree with values calculated from the kinetic con­stants measured in part II.

Modelling the Complete Molecular Weight Distribution in Chain Growth Polymerizations

2016 ◽  
Vol 1819 ◽  
Author(s):  
Ramiro Infante-Martínez ◽  
Enrique Saldívar-Guerra ◽  
Odilia Pérez-Camacho ◽  
Maricela García-Zamora ◽  
Víctor Comparán-Padilla
Keyword(s):  
Molecular Weight ◽  
Free Radical ◽  
Radical Polymerization ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Chain Transfer ◽  
Free Radical Polymerization ◽  
Experimental Program ◽  
Chain Growth ◽  
Coordination Polymerization

ABSTRACTThis work shows the development of several models for chain-growth polymerizations that admit the direct calculation of the complete molecular weight distribution of the polymer. The direct and complete calculation implies that no statistical mean values are employed as in the moments method neither numerical approximations like in the minimum-squared based methods. The free radical polymerization of ethylene (LDPE) and the coordination via metallocenes polymerization of ethylene (HDPE) are taken as examples for analysis.In the free radical polymerization case, the conventional scheme for chain-growth polymerization is adopted, with steps for initiation, propagation, chain transfer to small species and the additional step of chain transfer to dead chains [1]. The kinetic parameter are obtained from the open literature. Two kind of reactors were modelled: batch and continuous stirred tank reactor. For this last case, a simulation strategy was considered in which the run started from an initial known population of dead chains. Results show that typical non-linear polymerization profiles for the molecular weight distribution are obtained. For the coordination polymerization of ethylene via metalocenes, the standard coordination model was employed [2]. A two-site catalyst was considered and kinetic parameters reported in the open literature were used. For this study an experimental program in a lab-scale reactor was undertaken in order to obtain modelling data [3]. Results show that the standard model adequately reproduces the experimental data in the kinetic and molecular attributes of the polymer.

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