In Figure ) we explore the effect of the monomer bulkiness on the phase diagram of PEC in equilibrium with a supernatant containing NaCl only. Because our excluced-volume potential is much steeper at small distances than the bonding potential, an increase in size of the particle representing the monomeric units, σ mon , implies a simultaneous increase in the mean bond length to ⟨b⟩ ≈ σ mon , thereby decreasing the effective charge density along the chain contour. Lowering the charge density on the polymer decreases the entropic gain from the release of counterions and suppresses the elecrostatic interactions between the chains, thereby destabilizing the PEC phase. This decrease acts in synergy with an increased range of steric repulsion. Consequently, an increase in σ mon shrinks the co-existence region. Notably, if we use σ mon = 1.30σ ≈ 0.46 nm on Figure ), the pressure-composition protocol does not indicate a stable PEC phase at c NaCl ≈ 532mM, whereas a stable PEC phase exists at the same c NaCl if we use σ mon = 1.20σ ≈ 0.43 nm. Eventually, if we use σ mon = 1.40σ ≈ 0.50 nm, there is no phase coexistence at all and the phase diagram contains only a single-phase region.