An eco-friendly approach towards furanic-aliphatic polyesters as sustainable alternatives to aromaticaliphatic polyesters is presented. In this approach, biobased dimethyl 2,5-furandicarboxylate (DMFDCA) is polymerized with various ( potentially) renewable aliphatic diols via Candida antarctica Lipase B (CALB)-catalyzed polymerization using a two-stage method in diphenyl ether. A series of furanic-aliphatic polyesters and oligoesters is successfully produced via enzymatic polymerization. Some products reach very high M w (weight average molecular weight) values of around 100 000 g mol −1 . Studies on the effect of the diol structure on the enzymatic polymerization indicate that CALB prefers long-chain alkane-α,ω-aliphatic linear diols containing more than 3 carbons. We also found that the molecular weights of the obtained furanic-aliphatic polyesters increase steadily with the increase of reaction temperature from 80 to 140°C. MALDI-ToF MS analysis reveals that five polyester species may be present in the final products.They were terminated with the ester/-OH, ester/ester, -OH/-OH, no end groups (cyclic), and ester/aldehyde groups, respectively. Furthermore, the structure-property relationships were studied by comparing the crystalline/thermal properties of a series of relevant furanic-aliphatic polyesters.

2,5-Bis(hydroxymethyl)furan is a highly valuable biobased rigid diol resembling aromatic monomers in polyester synthesis. In this work, it was enzymatically polymerized with various diacid ethyl esters by Candida antarctica Lipase B (CALB) via a three-stage method. A series of novel biobased furan polyesters with number-average molecular weights (M(n)) around 2000 g/mol were successfully obtained. The chemical structures and physical properties of 2,5-bis(hydroxymethyl)furan-based polyesters were fully characterized. Furthermore, we discussed the effects of the number of the methylene units in the dicarboxylic segments on the physical properties of the furan polyesters.

To facilitate the ongoing transition toward a circular economy, the availability of renewable materials for additive manufacturing becomes increasingly important. Here, we report the successful fabrication of complex shaped prototypes from biobased acrylate photopolymer resins, employing a commercial stereolithography apparatus (SLA) 3D printer. Four distinct resins with a biobased content ranging from 34 to 67% have been developed. All formulations demonstrated adequate viscosity and were readily polymerizable by the UV-laser-based SLA process. Increasing the double-bond concentration within the resin results in stiff and thermally resilient 3D printed products. High-viscosity resins lead to high-resolution prototypes with a complex microarchitecture and excellent surface finishing, comparable to commercial nonrenewable resins. These advances can facilitate the wide application of biobased resins for construction of new sustainable products via stereolithographic 3D printing methods.

Furan-2,5-dicarboxylic acid (FDCA)-based furanic-aliphatic polyamides can be used as promising sustainable alternatives to polyphthalamides (semiaromatic polyamides) and be applied as high performance materials with great commercial interest. In this study, poly(octamethylene furanamide) (PA8F), an analog to poly(octamethylene terephthalamide) (PA8T), is successfully produced via Novozym 435 (N435)-catalyzed polymerization, using a one-stage method in toluene and a temperature-varied two-stage method in diphenyl ether, respectively. The enzymatic polymerization results in PA8F with high weight-average molecular weight (M̅(w)) up to 54000 g/mol. Studies on the one-stage enzymatic polymerization in toluene indicate that the molecular weights of PA8F increase significantly with the concentration of N435; with an optimal reaction temperature of 90 °C. The temperature-varied, two-stage enzymatic polymerization in diphenyl ether yields PA8F with higher molecular weights, as compared to the one-stage procedure, at higher reaction temperatures. MALDI-ToF MS analysis suggests that eight end groups are present in the obtained PA8F: ester/amine, ester/ester, amine/amine, acid/amine, ester/acid, acid/acid, ester/amide, and no end groups (cyclic). Compared to PA8T, the obtained PA8F possesses a similar Tg and similar crystal structures, a comparable Td, but a lower Tm.

Bio-based commercially available succinate, itaconate and 1,4-butanediol are enzymatically co-polymerized in solution via a two-stage method, using Candida antarctica Lipase B (CALB, in immobilized form as Novozyme® 435) as the biocatalyst. The chemical structures of the obtained products, poly(butylene succinate) (PBS) and poly(butylene succinate-co-itaconate) (PBSI), are confirmed by 1H- and 13C-NMR. The effects of the reaction conditions on the CALB-catalyzed synthesis of PBSI are fully investigated, and the optimal polymerization conditions are obtained. With the established method, PBSI with tunable compositions and satisfying reaction yields is produced. The 1H-NMR results confirm that carbon-carbon double bonds are well preserved in PBSI. The differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) results indicate that the amount of itaconate in the co-polyesters has no obvious effects on the glass-transition temperature and the thermal stability of PBS and PBSI, but has significant effects on the melting temperature.

Enzymatic polymerization provides an excellent opportunity for the conversion of renewable resources into polymeric materials in an effective and sustainable manner. A series of furan‐based copolyesters was synthesized with normalMnormalw‾ up to 35 kg mol−1, by using Novozyme 435 as a biocatalyst and dimethyl 2,5‐furandicarboxylate (DMFDCA), 2,5‐bis(hydroxymethyl)furan (BHMF), aliphatic linear diols, and diacid ethyl esters as monomers. The synthetic mechanism was evaluated by the variation of aliphatic linear monomers and their feed compositions. Interestingly, there was a significant decrease in the molecular weight if the aliphatic monomers were changed from diols to diacid ethyl esters. The obtained copolyesters were thoroughly characterized and compared with their polyester analogs. These findings provide a closer insight into the application of enzymatic polymerization techniques in designing sustainable high‐performance polymers.

Sustainable FDCA-based semi-aromatic polyamides are produced via enzymatic polymerization. The enzymatic polymerization kinetics, effect of diamine chain length, and thermal properties of the resulting polyamides are investigated.

Biobased saturated aliphatic polyesters and photo-curable unsaturated aliphatic polyesters are enzymatically polymerized, and their structure–property relationships are systematically studied.