Estimation of Reactivity Ratios from Multicomponent Copolymerizations

Rudin, Alfred; Ableson, W. R.; Chiang, S. S. M.; Bennett, G. W.

doi:10.1080/10601327308060494

Cited by 18 publications

(3 citation statements)

References 19 publications

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“…The correct approach for determining ternary reactivity ratios is to use the experimental data directly from terpolymerization experiments and estimate reactivity ratios. Such studies based on ternary experimental data are extremely limited and rather unclear with respect to experimental implementations, which has led to very little use of their estimation schemes . In a recent publication, we conducted a thorough study of this problem and presented a novel approach based on the error‐in‐variables‐model (EVM) parameter estimation method, which provided reliable reactivity ratios for terpolymerization systems clear of the approximation and restriction of using binary reactivity ratios …”

Section: Introductionmentioning

confidence: 99%

Design of Optimal Experiments for Terpolymerization Reactivity Ratio Estimation

Kazemi¹,

Duever²,

Penlidis³

2015

Macro Reaction Engineering

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A model-based design of experiments is implemented for the problem of reactivity ratio estimation in terpolymerizations for the first time in the literature. Optimal terpolymerization feed compositions are calculated using a design criterion, based on the Error-in-Variables-Model (EVM) approach. The results show that there are three optimal feed compositions with their locations naturally dependent on the values of the reactivity ratios. However, the interesting observation is that in almost all cases the optimal feed compositions are located close to the corners of the terpolymerization composition triangular plot. In addition, the impact of the reactivity ratio values on the location of the optimal feed compositions is explored and ''practical heuristics'' are presented.

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Section: Introductionmentioning

confidence: 99%

Design of Optimal Experiments for Terpolymerization Reactivity Ratio Estimation

Kazemi¹,

Duever²,

Penlidis³

2015

Macro Reaction Engineering

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“…The estimation methods have been shown to have a strong effect on the uncertainty bounds of the point estimates. Linear and nonlinear least squares methods have been used for estimation of ternary reactivity ratios. The error‐in‐variables model (EVM), which is a modified nonlinear method, is believed to be the most statistically correct method for reactivity ratio estimation in multicomponent polymerization systems, since it considers the error present in all dependent and independent variables .…”

Section: Introductionmentioning

confidence: 99%

“…This method is also ideal for use with nonlinear models such as the instantaneous terpolymer composition model of Alfrey and Goldfinger (AG) . Most previous studies on estimation of ternary reactivity ratios, which assume low composition drift at the early stages of polymerization, have performed low conversion polymerizations . Since errors are accentuated at low conversions, it may be more beneficial to estimate reactivity ratios using medium‐high conversion polymerization data …”

Section: Introductionmentioning

confidence: 99%

Terpolymerization of Triisopropylsilyl Acrylate, Methyl Methacrylate, and Butyl Acrylate: Reactivity Ratio Estimation

Yousefi

Jannesari

Pazokifard

et al. 2019

Macro Reaction Engineering

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Ternary monomer reactivity ratios of triisopropylsilyl acrylate (SiA), methyl methacrylate (MMA), and n‐butyl acrylate (BA), as common monomers in self‐polishing coatings (SPCs) binders are obtained using experimental data collected from free radical bulk polymerization at 70 °C. Different terpolymerizations at low and medium‐high conversions are performed at optimized feed compositions. Estimations are made using the error‐in‐variables model (EVM) framework, applying the recast form of the Alfrey–Goldfinger (AG) model and a direct numerical integration (DNI) approach to the collected data. Estimations from individual low and medium‐high conversion data are compared to those found with the combined data (full conversion range data). The highest certainty in point estimates are obtained with analysis of the full conversion range data. Furthermore, the reactivity ratios determined from the combined data fall between those found with analysis of individual low and medium‐high conversion data, another corroboration of reliable data collection. Reactivity ratios determined from analysis of the combined data (rSiA/MMA = 0.4185, rMMA/SiA = 1.3754, rSiA/BA = 0.8739, rBA/SiA = 0.5736, rBA/MMA = 0.3692, rMMA/BA = 1.7919) are used in the recast AG model to predict cumulative terpolymer composition as a function of conversion. The experimental data and model prediction show satisfactory agreement.

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Molecular weight distributions in terpolymerization of ?-methylstyrene/styrene/acrylic acid in continuous stirred tank reactor

Lee

Cheong

Lee

et al. 2000

J. Appl. Polym. Sci.

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Free‐radical terpolymerization of α‐methylstyrene/styrene/acrylic acid (AMS/ST/AA) in a continuous stirred tank reactor (CSTR) was studied theoretically and experimentally. A series of reactions were conducted to investigate the effect of the reaction temperature, residence time, solvent contents, initiator concentration, chain‐transfer agent level, and different monomer compositions on the molecular weight distribution (MWD). The mathematical model based on “the instantaneous property method (IPM)” and the pseudokinetic rate constant method was introduced and modified to predict the MWD of the bulk terpolymer produced in a CSTR. The effects of process variables were included in the mathematical model. Extensive comparisons were made between the theoretical results and experimental values. The rate of the free‐radical terpolymerization of AMS/ST/AA was comparatively slow and it was found that the concentration of α‐methylstyrene had a strong influence on the molecular weight and polydispersity of the MWD. This presumably reflected the existence of a normal bimolecular termination rate and a slow propagation rate due to steric hindrances at the doubly substituted vinyl carbon atom or transfer of the allylic hydrogen from the α‐methyl group. Good agreement was obtained between calculated MWD and the experimental one by assuming that the disproportionation termination of free radicals was the dominant chain‐stoppage mechanism. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 479–487, 2001

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Estimation of Reactivity Ratios from Multicomponent Copolymerizations

Cited by 18 publications

References 19 publications

Design of Optimal Experiments for Terpolymerization Reactivity Ratio Estimation

Design of Optimal Experiments for Terpolymerization Reactivity Ratio Estimation

Terpolymerization of Triisopropylsilyl Acrylate, Methyl Methacrylate, and Butyl Acrylate: Reactivity Ratio Estimation

Molecular weight distributions in terpolymerization of ?-methylstyrene/styrene/acrylic acid in continuous stirred tank reactor

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