Vast quantities of the natural terpene (R)‐limonene can be collected from food waste. Epoxidation of its two double bonds provides limonene dioxide (LDO), a difunctional epoxy monomer. However, LDO is a mixture of four isomers, two of which (trans‐LDO) are actually difunctional while the others (cis‐LDO) have one epoxide group which is significantly less reactive, as revealed by Fourier transformed infrared spectroscopic analysis of formulations cross‐linked with polyethylene imine. These results are also confirmed when preparing epoxy formulations using respectively cis or trans isomers. From DFT calculations, the reactivity of each epoxide group of LDO has been assessed in model reactions with primary and secondary amines, in the presence of amine or alcohol hydrogen‐bond donors. The kinetics of cross‐linking has also been probed by differential scanning calorimetry. As measured by dynamic mechanical analysis, the resulting epoxy resins based on trans isomers have a storage modulus of ca 1GPa at room temperature and a glass transition temperature (Tg) of 70°C. These results demonstrate that trans LDO is a promising bio‐based epoxy monomer, which could be used as an alternative to petroleum‐based epoxy monomers.

Lanthanide dodecyl sulfates, LnDSx, are remarkably effective to catalyze the reaction of diepoxides with diamines in the liquid and solid states, the key reaction in the formation of epoxy thermosets....

Self-immolative polymers are a class of stimuli-responsive macromolecules that can unzip down to monomer level. Among those, aliphatic polyaldehydes are particularly attractive due to their ability to rapidly depolymerize at ambient temperatures. By virtue of their thermal fragility, their preparation is challenging, and no mechanistic details exist about their synthesis. This study aims at clarifying the mechanism of the anionic polymerization of aliphatic aldehydes. For this purpose, several aliphatic aldehydes were polymerized using a variety of initiators. It was found that irrespective of the nature of the initiating species, the enolate formed between the initiator and the monomer is actually triggering the polymerization. The formation of an enolate is also responsible for a chain-transfer reaction to monomer, which limits the molecular weight of the polymer (k tr /k p = 0.0036). The microstructure of the polymer was determined by solid-state 13 C nuclear magnetic resonance spectroscopy. It was found that all anionic polymers are linear, mostly isotactic (mm > 60%), and crystalline. These polymers are prone to depolymerize at room temperature in solution, making them interesting candidates as self-immolative polymers.

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