Molar mass distribution free radical addition polymerization

In free radical addition polymerization the distribution of molar mass depends upon the mechanism of termination. The simplest case to consider is when the mechanism is through disproportionation and is equal to the kinetic chain length v. In this case the chain grows and terminates at the length to which it had grown. At this point it is necessary to define a new... 

In copolymers, additional to the molar mass distribution, a distribution of chemical composition is present The term chemical heterogeneity refers to the differences in the relative percentage of monomers among copolymeric chains of different molar masses. A major source for chemical heterogeneity is the free radical polymerization of monomers with unequal reactivities resulting in different rates of incorpora-... 

Vicente et al. [30] used the heat of reaction and the open-loop observers developed in Section 7.2.5.3 to determine the concentration of monomer and CTA and hence to infer the instantaneous number-average molar masses during emulsion homo- and copolymerization reactions. In addition, the authors used the inferred values for online control of the molar mass distributions of copolymers with predefined distributions. They demonstrated that polymer latexes with unimodal MMD with the minimum achievable polydispersity index in free-radical polymerization (PI = 2) and bimodal distributions could be easily produced in linear polymer systems [15, 30]. 

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