The quest for sustainable monomers and “green” synthetic pathways for the design, fabrication, and modification of various polymers is of great importance and attracts a great deal of attention. Here, a highly versatile and novel bio-based platform was developed by reacting castor oil with propiolic acid for performing amino-yne click reactions. Owing to the electron-deficient nature of the propiolic acid esters, amino-yne click reactions were conducted with ease at room temperature, in the absence of any catalyst and solvent (as long as the amines were low-viscosity liquids at room temperature), and within 5 min. Several primary and secondary amines were shown to react readily with the developed platform. Furthermore, thermosets were prepared by using the propiolated castor oil and multifunctional amines. The prepared thermosets displayed improved thermal properties and elastomer-like mechanical properties.

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An organocatalyst-mediated, extremely rapid, robust, and practical poly(disulfide) synthesis method is introduced to polymer chemistry. A variety of organocatalysts were initially screened using commercially available 1,6-hexanedithiol and diisopropyl azodicarboxylate (DIAD) to reveal the best catalyst for the process. Remarkably, although a very low amount of catalyst loading (5%), all the catalysts examined afforded poly(disulfide) in 1 min with low to high molecular weights. Among them, triphenylphosphine was selected as the suitable catalyst after the kinetic measurements and used to determine the optimum conditions for polymerization. Various poly(disulfide)s with molecular weights up to 85.6 kDa could be successfully prepared using optimum conditions. Poly(disulfide) synthesis was also attempted with a "catalyst-free" approach, it was found that a polymer can be prepared under this condition, and its molecular weight increases with increasing temperature. The obtained polymers were characterized using common spectroscopic measurements, and the results revealed that the hydrazine unit derived from DIAD was incorporated into polymer chains as an end-capping agent. Also, a depolymerization study was achieved on a model poly(disulfide) using dithiothreitol as a reducing agent. It is believed the straightforward poly(disulfide) synthesis method comprising mild conditions introduced in this study will be of great interest in synthetic polymer chemistry.