The insertion of long hydrocarbon chains between ester groups in polyester allows for introduction and modulation of crystallinity, which can result in enhanced performance approaching high-density polyethylene. We report a convenient synthesis of building blocks for long-chain aliphatic polyesters via an aqueous C1 polymerization. The macromonomers include ω-hydroxyacid esters, α,ω-diols and α,ω-diacids. The length of hydrocarbon chain segment (C20–C60) can be controlled by the ratio of monomer/initiator in the C1 polymerization. The obtained polyesters from condensation of the long-chain ω-hydroxyacid esters have thermal and mechanical properties indistinguishable from related materials derived from biomass.