Molecular-weight distribution of linear polycondensation polymers. Flory theory

Mizerovskii, L. N.; Padokhin, V. A.

doi:10.1007/s10692-013-9458-4

Cited by 5 publications

(24 citation statements)

References 19 publications

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“…Underlying the models of polycondensation products distribution is the theory by P. Flory and W. Carothers, the principal provisions of which are as follows [8][9][10][11][12]: а) the formation of a polymer occurs statistically. To obtain a polymer with n recurring links, all possible combinations of polymers-predecessors are used, which can interact thereby forming this product; b) similar terminal functional groups of polymers have the same reactivity that is independent of the length of the polymer chain.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

“…Recently, scientists have intensively studied the role in polycondensation of the processes of forming the macrocyclic products at the expense of competitive intramolecular interaction between different terminal groups. That relates to the observed anomalous increase in the degree of polydispersity (DPD) (a ratio of the weight average polymerization degree to average) above the limit value of 2, following from the Flory-Carothers theory [10,11]. The formation of macrocycles of different size in the processes of polyesterification has been recently proven for the first time experimentally using the methods of elution liquid chromatography and matrixactivated laser desorption/ionization (MALDI TOF) [9].…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

“…Some problems that emerge in polycondensation theory should be stated differently for the equilibrium condensation telomerization. Thus, from the standpoint of polycondensation theory, of great interest is the behavior of the system in the neighborhood of the hypothetical singular point, when the complete conversion of monomer has been achieved and a single giant polymer molecule has been formed [10,11,14]. It was suggested in [11,12] that the actual conversion during polycondensation does not reach 100 % with the process terminated at earlier stages.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

“…When constructing a model, we considered the distribution of equilibrium condensation telomerization products from the standpoint of general patterns in the theory of polycondensation processes [1,2,[8][9][10][11][12]. According to them, the equilibrium condensation telomerization occurs as a system of successive equilibria, resulting in a growth and disruption of the chain.…”

Section: Distribution Model Of the Equilibrium Condensation Telomerizmentioning

confidence: 99%

See 3 more Smart Citations

Construction and investigation of the computer model of distribution of the composition of products from equilibrium condensation telomomerization

Kondratov

Yevtushenko

Kravchenko

2019

EEJET

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Section: Literature Review and Problem Statementmentioning

confidence: 99%

Section: Literature Review and Problem Statementmentioning

confidence: 99%

Section: Literature Review and Problem Statementmentioning

confidence: 99%

Section: Distribution Model Of the Equilibrium Condensation Telomerizmentioning

confidence: 99%

See 2 more Smart Citations

Construction and investigation of the computer model of distribution of the composition of products from equilibrium condensation telomomerization

Kondratov

Yevtushenko

Kravchenko

2019

EEJET

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“…Accordingly, we should note that the molecular weight distribution of PA-6 linear macromolecules is governed by Flory theory [11], while the weight percent of any x-mer is calculated from the relation…”

mentioning

confidence: 99%

Composition of Water-Soluble Substances in Polyamide-6 Produced on a Cascade Polyamide Production Line

Bazarov

Khromova

Sadivskii³

2014

Fibre Chem

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Long-term observations of the composition of unextracted granulate and extraction water generated during the industrial process for producing PA-6 on a Polymer Engineering cascade polyamide production line have shown that despite fluctuations in the process parameters for synthesis of PA-6, on this line the amount of cyclic oligomers exceeds the equilibrium value by a factor of 1.6-1.7 and remains practically constant. The amount of residual caprolactam, on the other hand, depends considerably on fluctuation in these parameters, in a number of cases turning out to be less than the equilibrium values as a result of entrainment of its vapor from the polycondensation reactors by the stream of inert gas. From the data obtained, it follows that during the cyclic oligomer extraction process under commercial conditions, cyclic oligomers with n e" 5 are not completely removed. Concentrations of cyclic oligomers in the polymer granulate that are systematically higher than the equilibrium values should be considered as evidence that they are formed in excess in the "oligomer splitting" stage, preceding the actual hydrolytic polymerization of caprolactam, and that they slowly disappear during the latter stage.The results of studies conducted in the second half of the last century provide a basis for assuming that hydrolytic polymerization of caprolactam (CL) can be quantitatively described in terms of three equilibria:-hydrolysis of caprolactam NH K 1 (CH 2 ) 5 | + H 2 O H 2 N (CH 2 ) 5 COOH, C=O (I) -conversion of caprolactam to units of linear chains O NH K 2 n (CH 2 ) 5 | (-HN (CH 2 ) 5 C-) n , C=O (II)

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Reversible Stepwise Condensation Polymerization with Cyclization: Strictly Alternating Co-polymerization and Homopolymerization Based upon Two Orthogonal Reactions

Lang

Kumar

2021

Macromolecules

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In a preceding work [10.1021/acs.macromol.1c00718Macromolecules2021], we have introduced a simple recursive scheme that allows us to treat stepwise linear reversible polymerizations of any kind with cyclization. This approach is used to discuss the polymerization of linear Gaussian strands (LGS) with two different reactive groups A and B on either chain end that participate in two orthogonal reactions and the strictly alternating copolymerization of LGS that carry A reactive groups with LGS equipped with type B reactive groups. The former of these cases has not been discussed theoretically in literature, the latter only regarding some special cases. We provide either analytical expressions or exact numerical solutions for the general cases with and without cyclization. Weight distributions, averages, polydispersity, and the weight fractions of cyclic and linear species are computed. All numerical solutions were tested by Monte-Carlo simulations.

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Molecular-weight distribution of linear polycondensation polymers. Flory theory

Cited by 5 publications

References 19 publications

Construction and investigation of the computer model of distribution of the composition of products from equilibrium condensation telomomerization

Construction and investigation of the computer model of distribution of the composition of products from equilibrium condensation telomomerization

Composition of Water-Soluble Substances in Polyamide-6 Produced on a Cascade Polyamide Production Line

Reversible Stepwise Condensation Polymerization with Cyclization: Strictly Alternating Co-polymerization and Homopolymerization Based upon Two Orthogonal Reactions

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