In this article, 10-undecenoic acid, based on castor oil, was used a raw material for the synthesis of alternating copolymers. -Unsaturated fatty esters as alkyl 10-undecenoates were prepared by the esterification reaction of 10-undecenoic acid with alkyl alcohol. A series of comb-like copolymers were synthesized by free radical polymerization from maleic anhydride and alkyl 10-undecenoates copolymers with different length of alkyl side chains in a toluene solution. These copolymers were investigated by H-1 and C-13 nuclear magnetic resonance, Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry (DSC). The copolymers were obtained in a low molecular weight in a range 3370-12,240 g mol(-1) and their structural characterization indicated the formation of alternating copolymers. DSC characterization revealed that these comb-like copolymers showed amorphous to semicrystalline behavior by increasing the length of side chains. The bio-based comb-like copolymers allow for the development of new polymeric materials for several applications. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1039-1045