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Nitroxide-mediated homopolymerization and statistical copolymerization of commercially available methacrylates derived from sustainable feedstocks (isobornyl methacrylate (IBOMA) and a mixture of methacrylic esters with an average alkyl side chain length of 13 units (termed C13MA)) was conducted in organic solvent (toluene) and in dispersed aqueous media using an oil-soluble unimolecular initiator (Dispolreg 007) without any controlling comonomers in a controlled manner. IBOMA homopolymerization in emulsion at 83−100 °C revealed the optimal polymerization temperature of 90 °C giving relatively narrow molecular weight distributions (1.46 < dispersities (Đ) < 1.58) and conversion up to 83% in a relatively short time (2 h). IBOMA/C13MA statistical copolymerizations yielded copolymers with tunable glass transition temperature (T g ) prepared in emulsion (−52 °C < T g < 123 °C) and in organic solvent (−40 °C < T g < 169 °C). Resins made in emulsion at 90 °C proceeded up to 92.7% conversion with monomodal molecular weight distributions (M̅ n up to 68,000 g mol −1 and Đ = 1.62−1.72) and were colloidally stable (24% solids and final average particle sizes of 270−481 nm). Furthermore, chain end fidelity was verified by chain extensions with IBOMA and C13MA monomers in both emulsion and organic solvent. These results constitute a readily scalable route to make polymers via nitroxide-mediated polymerization with controlled architecture using biobased feedstocks without the hazards of bulk or homogeneous organic solvent polymerization.

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Polymers with boronic ester dynamic covalent bonds were synthesized by nitroxide-mediated miniemulsion polymerization of isobornyl methacrylate (IBOMA), alkyl methacrylates (average aliphatic size of 13.0, C13MA), glycerol monomethacrylate (GMMA), and 4-vinylphenylboronic acid (VPBA). The miniemulsion polymerization of all monomers was enabled by the esterification reaction between GMMA and VPBA and the synthesis of (VPBA + GMMA) dimer prior to the polymerization. The formation of boronic ester dynamic covalent bonds was confirmed by rheological and mechanical measurements, indicating a higher stiffness by increasing the dimer content from 5% to 15% in the initial feed. Cross-linked polymers showed high reprocessing capability with a comparatively simple recycling process (at 80 °C for 45 min) and a high organic solvent absorbance of polymers (swelling ratio up to 153%). Furthermore, it was shown that the addition of VPBA and GMMA significantly improved the heat resistance of polymers up to 121 °C, compared to the IBOMA/C13MA copolymers (without GMMA and VPBA functional monomers).

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Nitroxide mediated polymerization (NMP) of methacryloisobutyl POSS (POSSMA) was conducted in a dispersed aqueous miniemulsion at 90 C, resulting in stable latexes with particle sizes = 225-260 nm at solids loading = 22%. POSSMA homopolymers with M n up to 35.9 kg mol −1 (Đ < 1.53) was prepared using Dispolreg 007 alkoxyamine without any controlling comonomers, as is traditionally required for NMP of methacrylates. Copolymers with different ratios of POSSMA and bio-based C13 methacrylic esters were also synthesized (monomer conversion [X] up to 96.5% and 1.42 < Đ < 1.68) to prepare polymer resins with a wide range of glass transition temperatures (T g) or melting points (T m) (−30 C < T g , T m < 96 C). The resulting homopolymers and copolymers exhibited semi-crystalline properties, with crystallite size of 20.3-44.4 Å.