Polydispersity index linear condensation

A polymerization that provides a transition into a discussion of gelation is the condensation of an excess of A-B with a small amount of an /-functional monomer, R-A/, that contains / equivalent functional groups of Type A, but no functional groups of Type B.[3 Linear chains are obtained when / is 1 or 2, but multichain condensation polymers are produced when/>2. At high conversion the polydispersity index depends only on/. 

The weight-average molar mass for linear condensation polymers also diverges as the extent of reaction p—> 1 (see Fig. 1.19). The polydispersity index of the linear condensation polymers,... 

At what extent of reaction p is the polydispersity index of a linear condensation polymerization sample equal to M -jMn = 1.5 ... 

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