The Biginelli reaction was applied as a simple one-pot multicomponent polycondensation approach to efficiently synthesize a set of 15 new and fully renewable poly(3,4-dihydropyrimidin-2(1H)-one)s. One of six bis-acetoacetates or three bis-acetoacetamides, terephthalic aldehyde and (methyl-)urea were used as renewable starting materials in various combinations, hence significantly expanding the known set of monomers as well as polymer structures. The bis-acetoacetates and bis-acetoacetamides with different spacer lengths were synthesized in yields of up to 99% in a one-step process. Thermal analysis of the obtained set of polymers revealed high glass transition temperatures (T g ) ranging from 160 to 308°C. The T g was tunable in small steps of 10°C by simple variation of bis-acetoacetate or bis-acetoacetamide monomers as well as the choice of (methyl-)urea. The poly (3,4-dihydropyrimidin-2(1H)-one)s showed good thermal stability with T d5% values well above the respective high T g values.

Three acrylate monomers featuring different side-groups are synthesized in yields up to 94% in a one-pot procedure using the versatile Passerini-three-component reaction. The procedure for their miniemulsion polymerization into polymeric particles with tunable sizes is established. Ethylene glycol dimethacrylate is introduced as comonomer to induce crosslinking and enable the production of microgels. Besides the shelf life of the miniemulsions, the dependence of the particle size on the concentration of the surfactant (sodium dodecyl sulfate) and the crosslinker, as well as the sonication amplitude and time, is investigated. The particle size of the collapsed microgels range from 21 to 91 nm. The swelling of the microgels in organic solvents is studied.

The search for renewable monomers for radical polymerization techniques is of current interest due to the awareness of sustainability requirements in the chemical sciences. Herein, the synthesis and reversible addition-fragmentation chain-transfer (RAFT) polymerization of a renewable methacrylate monomer based on ricinoleic acid as sustainable starting material is presented. In addition, the hydroxy moiety of the ricinoleic acid is converted to an acetoacetate in order to allow for a post-polymerization modification (PPM) using the Biginelli-three-component reaction (B-3CR), rendering the presented monomer a renewable and highly flexible reactant for the synthesis of polymer materials. Consequently, RAFT polymerization yields macromolecules with a molecular weight of up to 15 000 g mol −1 and expectedly narrow molecular weight distributions with Ðs around 1.13. The feasibility of chain extension and block copolymer synthesis is demonstrated. Eventually, the PPM of the acetoacetate moiety of the polymer repeating units using the B-3CR is proven to be efficient with conversions of up to 95% of the acetoacetates, while the modification allows for a pronounced increase of the glass transition temperature to approximately room temperature compared to the unmodified polymers (T g = −50 °C).

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