Kinetics of Radical Chain Polymerization: 2. Linear Waves of Macroradical Growth

Resumo

The chain growth in radical chain polymerization is associated with the wave of transformation of primary radicals into macroradicals. The change in chain length n and molecular mass distribution R(t, n) with time t corresponds to the movement of a wave packet with velocity dn/dt and width ∆(n), both dependent on monomer concentration M(t). The formation of macroradicals in the absence of chain transfer when the rate constant of chain growth K(n) depends on n has been considered, and it has been shown that the packet is described by the Poisson distribution law with the event probability depending on K(n) and t. As K(n) decreases, R(t,n) narrows and its maximum shifts to the region of the minimum of K(n). Relations of K(n), M(t), and R(t, n) to dn/dt and ∆(n) have been found.