Driven by environmental considerations, the scientific community has directed great effort towards the synthesis of new materials derived from renewable resources. However, for photocurable resins, most commercially available building blocks still rely on petroleum-based precursors. Herein, we present a simple synthesis route for bio-based acrylate-modified polyester resins, whose viscosity is sufficiently low for processing them with vat photopolymerization 3D printing. The established synthesis route enables the gradual substitution of fossil-based raw materials with bio-based alternatives. The acid number, color and viscosity of the bio-based acrylic resins are characterized and photocurable formulations are prepared by adding a radical photoinitiator. The photopolymerization kinetics, and thermomechanical and mechanical properties of the photopolymers are investigated as a function of the resin structure and benchmarked against a commercially available petroleum-based counterpart. Finally, the processability of the new bio-based resins via digital light processing 3D printing is demonstrated and test specimens are successfully 3D printed with a resolution in the millimeter range.

In recent years, many efforts are being devoted to the development of new materials that originate from renewable resources. Polyesters are one of the most important classes of such materials and several bio-based monomers are available for their synthesis. In this work, the development of fully bio-based and solvent-free polyester polyol used for two-component polyurethane coatings on industrial scale is presented. Fossil-based raw materials were substituted with bio-based alternatives that are commercially available on a large scale. Properties of polyols and coatings were determined and measured. Polyols were characterized by the determination of acid number, hydroxyl number, glass transition temperature and refractive index, and measurement of viscosity, color and molecular weight. Coatings were characterized by the determination of mechanical properties, such as hardness, elasticity and impact resistance, and the measurement of optical properties such as gloss, haze, distinctness of image (DOI) and reflected image quality (RIQ) and weathering resistance. Three variations of bio-based polyol were synthesized, then the most suitable version was validated in a clear coat. The results showed that the properties of the bio-based polyol and coating met the requirements and were comparable to the properties of the synthetic counterpart. Results indicate that this newly developed 100% bio-based and solvent-free polyol can be used as a drop-in replacement for synthetic polyol. Furthermore, this work implies that the supply chain is established which allows the green transition in the paint industry.

In this work, the development of FDCA-based polyester resins for coil coatings in industrial environment is presented. The goal of our research was to prepare industrial coatings made from renewable materials with the same performance as the standard coating. Resins with 1%–41% of FDCA on polymer were synthesized and then used in a formulation for primer. Resins were characterized by the determination of non-volatile matter, acid value, hydroxyl value, glass transition temperature, and measurement of viscosity, color and molecular weight. Coatings were characterized by the determination of viscosity, density, non-volatile matter, adhesion, T-test, MEK test, reverse impact, and pencil hardness, as well as the measurement of gloss. FTIR measurements confirmed successful incorporation of FDCA into the polymer. The results showed that resins with up to 31% of FDCA on polymer can be used to prepare coil coating where the properties of resins comply with the requirements and are comparable to the properties of standard resin. Resins had non-volatile matter between 59.0 and 60.1%, an acid value up to 4.6 mg KOH/g, a hydroxyl value of 22.0–24.9 mg KOH/g and viscosity at 23 °C between 6100 and 7500 mPa.s. Nevertheless, with the increase in FDCA in the formulation, discoloration of the resin occurred and incompatibility with the solvents was observed, while up to 10 °C lower glass transition temperatures and up to 28% lower molecular weights of the resins were determined. For coatings prepared from FDCA-based resins, the properties improved or were comparable to the properties of coating prepared from standard resin. Adhesion improved with higher content of FDCA in the resin from 2 Gt to 0 Gt, while all coatings had gloss at 60° of 39%–41%, a reverse impact of 10 J and a pencil hardness of H/2H. T-bend test results varied between 2 T and 0.5 T and the results of the MEK test showed resistance > 100 DR.

The homopolymerization of itaconates results in relatively short polymer chains and low monomer conversions. To study whether copolymerization provides a more favorable result, dibutyl itaconate was copolymerized with n-butyl acrylate, methyl methacrylate and styrene. In addition to representing the most commercially preferred monomer families, these co-monomers were also chosen due to the differences in the secondary reactions that occur during polymerization at elevated temperatures. Experiments were conducted under semi-batch operating conditions at 110 °C with equal molar ratios of the co-monomer to dibutyl itaconate to enable direct comparison of the results. The impact of varying monomer compositions on polymer molecular mass distributions and polymerization rates was studied, with samples analysed using size exclusion chromatography and high-performance liquid chromatography.