Polymers

 Number average, Weight average and viscosity average molecular weight (Comparison): • We know that the number average molecular weight, Weight average molecular weight and viscosity average molecular weight are given by Number average, Weight average and viscosity average molecular weight. • For monodisperse sample Number average molecular weight = Weight average molecular weight. Number average molecular weight = Weight average molecular weight. • When a is unity Weight average molecular weight = viscosity average molecular weight. Weight average molecular weight = viscosity average molecular weight. • For a polydispersed polymer  Relation between number average,weight average and viscosity average molecular weight. as shown in fig below Distribution of molecular weights in a typical polymer sample. • Let us compare the number average molecular weight and weight average molecular weight.  The number average molecular weight and weight average molecular weight.