Polydispersity index is defined as ______ where Mw and Mn are the weight average and number average molecular masses respectively. a) Mw x Mn b) Mw/Mn c) Mn/Mw d) Mw – Mn

Polydispersity index is defined as ______ where Mw and Mn are the weight average and number average molecular masses respectively.

a) Mw x Mn

b) Mw/Mn

c) Mn/Mw

d) Mw – Mn

Expert Solution

Answer : b) Wm/Mn

Explanation :

Polydispersity index (PDI) is defines as the ratio of weight average molecular mass to the number average molecular mass. It gives an idea of the homogeneity of the polymer.

Polydispersity index for natural rubber is approximately 1 because there is identical chains and definite mass I.e Wm = Mn.

b) Mw/Mn

Rakesh answered 2 years ago

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