Isosorbide monoacrylate (IMA) is a fully bio-based monomer formed by the reaction between isosorbide and acrylic acid. From a fundamental point of view and as a potential substitute for the current petro-based and carcinogenic monomers, it is crucial to understand its behaviour during a conventional radical polymerization. To this end, the radical polymerizability of IMA has been investigated in depth under various conditions (i.e. different solvents or [IMA]/[Initiator(AIBN)] ratios). In all cases, plateaus are reached for Mn. The Mayo method of IMA free radical polymerization was carried out and the transfer to monomer (CtrM) constant was determined to be up to 1.4 × 10−3. Depending on the molecular weight, PIMA with a large range of Tg from room temperature to higher than 100 °C could be obtained. Furthermore, the treatment of high-Tg PIMA with succinic anhydride leads to a high-performance thermoset featuring thermomechanical properties close to those of commercial epoxy resins such as DGEBA-based resins (Tg = 116 °C and E′ = 4 GPa).