Kinetic analysis, of polymerization

The calculated functional dependence for [Ac] is inserted into the rate equation. An agreement between calculation and experiment should not be overestimated. An exact kinetic analysis of polymerization requires proof of the partial steps, and is very difficult. 

The high-pressure CSTRs have been designed with special emphasis on ideal mixing. A technique for the characterization of residence-time behavior under high-pressure conditions and during ethene polymerization has been developed [30]. Effective mixing ensures isothermal conditions within the CSTR which largely facilitates the quantitative kinetic analysis of polymerization reactions carried out in such a reactor. 

The kinetics analysis of polymerization reactions provides important information on the polymerization rate as a function of influencing variables as well as the influence of side reactions for deviations from what is called ideal kinetics. The following assumptions are made ... 

Kinetic Analysis of Cyclic Ether Polymerization by Fourier Transform NMR ... 

Figure 12. Model graphs for a kinetic analysis of an equilibrium polymerization (definition of variables of Equation 11)...

A systematic kinetic analysis of the binding site of an enzyme with the subunits of a polymeric substrate, in-... 

Kinetic analysis of a step polymerization becomes complicated when all functional groups in a reactant do not have the same reactivity. Consider the polymerization of A—A with B—B where the reactivities of the two functional groups in the B—B reactant are initially of different reactivities and, further, the reactivities of B and B each change on reaction of the other group. Even if the reactivities of the two functional groups in the A—A reactant are the same and independent of whether either group has reacted, the polymerization still involves four different rate constants. Any specific-sized polymer species larger than dimer is formed by two simultaneous routes. For example, the trimer A—AB—B A—A is formed by... 

Information of this kind opens new exact access to the kinetic analysis of further polymerization steps. 

EXAMPLE KINETIC ANALYSIS OF VINYL CHLORIDE POLYMERIZATION... 

When living centres are slowly generated, the polymerization accelerates with time. Older centres have time to grow to larger dimensions than the fresh centres. Several authors [22-24] have paid attention to kinetic analysis of living polymerizations with slow initiation, the most recent of these studies being that of Pepper [25]. 

Kinetic analysis of isobutene polymerizations initiated by BCh was recently used to distinguish between haloboration and self-ionization of the Lewis acid [Eq. (38)]. 

When protonic acids are used as initiators, the resulting anions do not interact with nucleophiles. Therefore, kinetic analysis of these systems is simpler than for polymerizations carried out in the presence of Lewis acids. A typical example is the polymerization of vinyl ethers initiated by triflic acid in the presence of dialkyl sulfides [37,38],... 

In the polymerization of 1,3-dioxolane and tetrahydrofuran it has been shown additionally that concentration of active centers is constant throughout the polymerization (both by direct determination and from analysis of polymerization kinetics). In some other polymerizations, believed to proceed as living processes, only the moderate molecular weights regions (M < 105) were studied thus, for example, no very high molecular weight polymers were obtained in the polymerization of oxazolines. 

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