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We investigate a new series of precise ion-containing polyamide sulfonates (PAS x Li), where a short polar block precisely alternates with a non-polar block of aliphatic carbons ( x = 4, 5, 10, or 16) to form an alternating (AB) n multiblock architecture. The polar block includes a lithiated phenyl sulfonate in the polymer backbone. These PAS x Li polymers were synthesized via polycondensation of diaminobenzenesulfonic acid and alkyl diacids (or alkyl diacyl chlorides) with x -carbons, containing amide bonds at the block linkages. The para - and meta -substituted diaminobenzene monomers led to polymer analogs denoted p PAS x Li and m PAS x Li, respectively. When x ≤ 10, the para -substituted diamine monomer yields multiblock copolymers of a higher degree of polymerization than the meta -substituted isomer, due to the greater electron-withdrawing effect of the meta -substituted monomer. The PAS x Li polymers exhibit excellent thermal stability with less than 5% mass loss at 300 °C and the glass transition temperatures ( T g ) decrease with increasing hydrocarbon block length ( x ). Using the random phase approximation, the Flory–Huggins interaction parameter ( χ ) is determined for p PAS10Li, and χ (260 °C) ∼ 2.92 reveals high incompatibility between the polar ionic and non-polar hydrocarbon blocks. The polymer with the longest hydrocarbon block, p PAS16Li, is semicrystalline and forms well-defined nanoscale layers with a spacing of ∼2.7 nm. Relative to previously studied polyester multiblock copolymers, the amide groups and aromatic rings permit the nanoscale layers to persist up to 250 °C and thus increase the stability range for ordered morphologies in precise ion-containing multiblock copolymers.