the effect of *body evaporation and addition* pathway on the mixing and growth of differently dye-labeled but otherwise identical monomers at time $t=0$. Note the homogeneous insertion of black monomers along the green polymer backbone and *vice versa* via the free monomers in the solution.[]{data-label="fig1"}](Fig1.eps){width="6.5in"}

The remainder of this paper is organised as follows: In Section \[sec2\], we introduce the moment equations for the generalized molecular pathway and study the equilibrium properties of the two moments of the length distribution. In Section \[sec3\], the dynamical equations for the moments are solved in the absence of polymer recombination and in the limit of vanishing fragmentation and nucleation rate constants. The analytical solutions are then compared with numerical solutions, and used to calculate the half-time and the apparent growth rate for the polymerisation kinetics. Finally, in Section \[sec4\], we discuss the results and findings of our theoretical analysis.

Master Equations and Moment Equations {#sec2}
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The molecular pathways that we include in our study are i) *primary nucleation*, ii) *end evaporation and addition*, iii) *body evaporation and addition* and iv) *scission and recombination*. [@cates_all; @knowles_two_stage; @Tiwari_2016] Our moment equations, derived from the generalized rate equations, allow us to probe the quantitative role 