End-coupling kinetics for bidisperse (2151, 21101) and monodisperse (21, 61, and 91) macromonomers: the dependence of the interfacial copolymer coverage n on scaled time θ (p R = 0.025). Linear (I), saturation (II), autocatalytic (III), and terminal (IV) regimes are separated by the dashed lines. The interface becomes unstable at the saturation time t s.
Linear and saturation regimes for fully and partially functionalized melts at different probabilities of end-coupling. Linear fits according to Eq. (10) are shown by the dashed lines. The short vertical lines mark the beginning (θ = θln) of logarithmic kinetics for the 2051 and 20101 systems with only long chains functionalized.
Linear and saturation regimes for fully and partially functionalized melts at different probabilities of end-coupling. Linear fits according to Eq. (9) and (11) are shown by the dashed lines. The short vertical lines mark the end of the linear regime and the beginning (θ = θdiff) of diffusion controlled kinetics for the 2150 and 21100 systems with only short chains functionalized.
The total interfacial area S (divided by the xy face area of the simulation box) vs. the interfacial copolymer coverage n. Results for p R = 0.25, 0.025 coincide.
Late stages of end-coupling in the polydisperse melts at different reaction probabilities p R. The black dotted line describes the monodisperse initial system with N A = N B = N = 5. The dashed lines show linear trends (exponential kinetics) for the polydisperse systems.
Time dependence of the density of units ρ A belonging to long (a) and short (b) macromonomers A in the system 21101 along the z-axis. (c) replots the data of (a) on a bilogarithmic scale, where h = l z /2 − z. The red dashed line demonstrates the diffusion controlled trend in the thickness of a growing microstructured copolymer layer. (d) presents snapshots of the melt morphology at different moments of time. At the snapshots, active ends of the short macromonomers (A particles in orange, B ones in light blue) and copolymer chains (A particles in red, B ones in dark blue) are shown. a AB = 50, p R = 0.25.
Dependence of the number average polymerization degree of copolymer, 〈N〉, on the interfacial copolymer coverage n for the systems 2151 and 21101.
Parameters of the reacting polydisperse macromonomers (the same for A and B).
The saturation copolymer coverages at the initial interface, n s, asymptotic interfacial copolymer density during reaction, c*, and equilibrium interfacial copolymer density for a corresponding randomly coupled melt, c ∞ S 0 = 1.18 is the area of the initial interface.
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