symbols: $\Delta S_{\rm{m}}$, $\Delta_{\rm{ab}} S_{\rm{m}}$; unit: $\pu{J mol-1 K-1}$
synonym: molar entropy of polymerization
https://doi.org/10.1351/goldbook.15400
Change of entropy, in a chain polymerization forming a homopolymer, associated with the conversion of one mole of monomer into polymer under isobaric and isothermal conditions.
Notes:
- Under defined standard conditions, the entropy of polymerization is designated \(\Delta S_{\rm{m}}^{\circ}\); thus, if the standard state refers to standard concentration, and the monomer behaves ideally, \(\Delta S_{\rm{m}} = \Delta S_{\rm{m}}^{\circ} + R\ln ([{\rm{M]}}_{0}/c^{\circ})\), where \([{\rm{M}}]_{0}\) denotes the starting monomer concentration and \(c^{\circ} = \pu{1 mol dm-3}\) is the standard concentration.
- The subscripts in \(\Delta_{\rm{ab}} S_{\rm{m}}\) denote the state of the monomer (a) and the state of polymer (b) (see enthalpy of polymerization (Note 2)).