Work out polymer degree of polymerisation instantly with clear inputs, formula shown and shareable results.
Degree of polymerisation is the number of repeat units per chain, so it is the number-average molar mass divided by the repeat unit's molar mass. Polystyrene at Mn = 250,000 with a 104.15 g/mol styrene unit averages about 2400 units. The Carothers equation gives an independent prediction from conversion alone, DP = 1/(1-p), which shows why step-growth polymers need conversions above 99% to reach useful chain lengths.
From molar mass
DP = Mn / M0
Carothers equation
DP = 1 / (1 - p)
Carothers applies to step-growth polymerisation at a given conversion; the mass route reflects what the chains actually are. A gap points to chain transfer or a chain-growth mechanism.
No - that needs the weight-average mass as well. PDI = Mw/Mn, and it is 1 for a perfectly uniform sample.