Polymerization kinetics model

High-Conversion Polymerization Kinetic Modeling Utilizing Gel Permeation Chromatography... 

Gel Permeation Chromatography (CPC) is often the source of molecular wei t averages used in polymerization kinetic modelling Q.,2). Kinetic models also r uire measurement of molecular weight distribution, conversion to polymer, composition of monomers in a copolymerization rea tion mixture, copolymer composition distribution, and sequence length distribution. The GPC chromatogram often reflects these properties (3,. ... 

The purpose of this paper is to propose solutions to the GPC interpretation problems fitting the needs of high conversion polymerization kinetic modelling. 

BALKE AND PATEL High-Cofiversioft Polymerization Kinetic Modeling 151... 

BALKE AND PATEL High-CottVersion Polymerization Kinetic Modeling 155... 

BALKE AND PATEL High-Conversiott Polymerization Kinetic Modeling 159... 

BALKE AND PATEL High-Conversiofi Polymerization Kinetic Modeling 167... 

BALKE AND PATEL High-ConVersion Polymerization Kinetic Modeling 169... 

BALKE AND PATEL High-Converslofi Polymerization Kinetic Modeling 175... 

An illustration of a series-parallel network is provided by the step-change polymerization kinetics model of Section 7.3.2. The following example continues the application of this model to steady-state operation of a CSTR. 

This problem continues Example 18-7 for use of the step-change polymerization kinetics model of Chapter 7 in a CSTR at steady-state. 

Yet Chien demostrated that it would be possible to obtain polyethylene with a Q value near the theoretical 2, with the homogeneous (CjH5)2TiCl2—A1(CH3)2C1 catalytic system, only if carefully controlled pseudosteady-state conditions are employed. In fact he showed mathematically that the relatively high experimental polydispersiiy (<,) tfom 2 to 5 in function of reaction time), is a natural consequence of a polymerization kinetic model based on non stationary first order initiation, chain propagation and bimolecular chain termination by recombination. 

New Techniques for the Study of Electrodes and their Reactions Electron Tunneling in Chemistry. Chemical Reactions over Large Distances Mechanism and Kinetics of Addition Polymerizations Kinetic Models of Catalytic Reactions Catastrophe Theory... 

POLYMERIZATION KINETICS MODELED BY THE CHEMICAL STOCHASTIC EQUATION... 

Olefin polymerization reactors will now be modeled using a bottom-up approach, from microscale to macroscale. In this section polymerization kinetic models will be introduced to describe polymerization rates and polymer microstructures, ignoring any phenomena that may take place in the mesoscale and macroscale. These models depend on the concentration of reagents and temperatures at the active site. As explained in the previous... 

In the case of SEC/FTIR characterization, a method for recovering the full distribution from the average comonomer composition was proposed based on a polymerization kinetics model and the deconvolution of the MWD [43]. It was found, however, that both SEC/FTIR and P-Tref/light scattering techniques generally lose part of the information on the bivariate distribution of molecular weight and comonomer composition [44]. 

Eree Radical Polymerization Kinetics Modeling the Rate Coefficient... 

On-line estimation may also be accomplished using first-principles polymerization kinetic models implemented on-line in the form of an extended Kalman filter (EKF) (as illustrated for example in Refs. 8 and 40-42). It should be pointed out that the choice of techniques for on-line estimation of polymer properties is still an active area of research and is very much dependent on the specifics of the polymer chemistry and available on-line instrumentation. 

Emulsion polymerization studies reported in the scientific literature are usually based on experiments with batch or semibatch reactor systems. Since most workers in the field are familiar with such reactors, the thrust of this discussion will be to compare continuous reactors with batch and semi-batch operations. The particular areas to be reviewed include (i) inhibitor effects, (ii) particle age distributions, (iii) particle nucleation, (iv) copolymerization, (v) particle morphology, (vi) temperature control and heat removal and (vii) polymerization kinetic models. 

A well-known emulsion polymerization kinetic model can be developed based on the following assumptions ... 

This free radical distribution function, determined via a Monte Carlo technique, was then incorporated into the two-phase emulsion polymerization kinetics model developed by Nelson and Sundberg [44, 45] to predict the monomer conversion versus time data available in the literature. Thus, the only difference between the kinetic model characterized by the following major governing equations [47] and that of Nelson and Sundberg is the method used for calculation of the average free radical population in each polymer phase. 

Polymerization Kinetic Modeling and Macromolecular Reaction Engineering... 

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