Page 410 - Elements of Chemical Reaction Engineering Ebook

Sec. 7.3 Polymerization 381
I Realizing that the j = 0 term in the summation is zero and after changing the index
of thie summation and some manipulation, we obtain
- 1 (E7-5.11)

(E7-5.12)

(E7-3.13)

I Plots of pn and pw along with the polydispersity, D, are shown in Figure E7-5.1.
I

PN Pw

1 .c 1.

0
(4
Figure E7-5.1 Moments of live polymer chain lengths: (a) number-average chain
length; (b) weight-average chain length; (c) polydispersity.

We note from Equation (7-69) that after a long time the,maximum value
of 0, will be reached:
@I,,

The distributions of live polymer species for an anionic polymerization canied
out in a CSTR are developed in Problem P7-19.