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Novel biobased multiblock polyesters poly­(2,5-furandimethylene succinate)-b-poly­(butylene succinate) (PFS-PBS) containing PFS and PBS blocks were synthesized in a full composition range via chain-extension reaction of dihydroxyl terminated poly­(2,5-furandimethylene succinate) (HO-PFS-OH) and poly­(butylene succinate) (HO-PBS-OH) prepolymers. High molecular weight polyesters were obtained, and the stability of double bonds in 2,5-bis­(hydroxymethyl)­furan was guaranteed via this preparation procedure. The obtained copolyesters were characterized with 1H NMR, gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, polarized optical microscopy, wide-angle X-ray diffraction, and the mechanical properties were also investigated. No transesterfication reaction happened during chain-extension reaction, and the expected multiblock chemical structure was obtained. The PBS block is crystallizable, while the PFS block is nearly amorphous. Crystallization temperature and degree of crystallinity gradually decreased with increasing PFS fraction, but the melting temperature of crystalline samples showed no sharp reduction (109.4–105.2 °C). The crystallization rate also decreased with incorporation of PFS during isothermal crystallization, but the crystallization mechanism remained unchanged at any composition. Finally, the PFS-PBS copolyesters exhibit widely tunable mechanical properties, ranging from semicrystalline thermoplastics to amorphous soft elastomer-like polymers.

Poly(butylene succinate) (PBS) and gelatin‐coated PBS electrospun membranes are evaluated for use as support materials to immobilize thrombin, an effective hemostat for topical injury, and three methods differing in whether and when gelatin is included are envisaged to prepare thrombin‐loaded PBS‐based electrospun membranes for use as rapid hemostatic materials. Both PBS and gelatin‐coated PBS membranes have high porosity, excellent wettability, rapid water penetration rate, and high water uptake, and thus are suitable support materials for thrombin. The thrombin immobilized onto gelatin‐coated PBS membrane has both high initial enzyme activity and high storage stability ascribed to the stabilizing effect of gelatin on thrombin activity. The hemostasis performance of thrombin‐immobilized membrane is evaluated in a rat liver model, showing shorter hemostasis time and less blood loss than clinically used gelatin sponge. The hemostasis mechanism is attributed to combined effects of thrombin and porous structure of electrospun membrane.

A novel biobased and biodegradable polyester, i.e., poly(butylene succinate-co-butylene 2-methylsuccinate) (P(BS-BMS)) was synthesized by succinic acid (SA), 2-methylsuccinic acid (MSA), and 1,4-butanediol (BDO) via a typically two-step esterification and polycondensation procedure. The chemical structure and macromolecular weight of obtained copolymers were characterized by 1H NMR, 13C NMR, and GPC. The melting temperature and degree of crystallinity were also studied by DSC, and it was found that the values were gradually decreased with increasing of MSA content, while the thermal stability remained almost unchanged which was tested by TGA. In addition, the biodegradation rate of the P(BS-BMS) copolymers could be controlled by adjusting the ratio of SA and MSA, and such biodegradability could make P(BS-BMS) copolymers avoid microplastic pollution which may be brought to the environment for applications in agricultural field. When we applied P(BS-BMS) copolymers as pesticide carriers which were prepared by premix membrane emulsification (PME) method for controlling Avermectin delivery, an improvement of dispersion and utilization of active ingredient was obviously witnessed. It showed a burst release process first followed by a sustained release of Avermectin for a long period, which had a great potential to be an effective and environmental friendly pesticide-release vehicle.