The synthesis and structural characterization of linear PolyC 3 polymers containing trimethylene-1,1-dicarboxylate structural repeat units, with C 6 F 13 and C 8 F 17 fluorinated side chains is described for the first time, and their properties compared with the traditional polyvinyl structures that display the fluorinated chain on every second rather than on every third carbon alongside the backbone. Homopolymers as well as statistical and block copolymers with npropyl and/or allyl trimethylene-1,1-dicarboxylate blocks have been obtained from PolyC 3 precursors containing diallyl trimethylene-1,1-dicarboxylate units, by reacting C 6 F 13 -C 2 H 4 -SH and C 8 F 17 -C 2 H 4 -SH thiols with the allyl groups using a thiol-ene post-polymerization modification reaction. Solid-state properties have been investigated by DSC for all the (co)polymers and by SAXS/WAXS for the C 8 F 17 homopolymer at several temperatures. The structure of the homopolymer consistently shows a coexistence of two smectic phases at room temperature, which can be identified as SmB and SmC. This coexistence is assumed to arise from the fact that the distances between carboxylic oxygens bonded to the same carbon are very close to the ones between the neighboring carboxylic oxygens alongside the backbone, resulting in two possible ways of packing the pendant fluoroalkyl chains arranged in an hexatic order.