Nowadays the issues related to the end of life of traditional plastics are very urgent due to the important pollution problems that plastics have caused. Biodegradable plastics can help to try to mitigate these problems, but even bioplastics need much attention to carefully evaluate the different options for plastic waste disposal. In this Minireview, three different end-of-life scenarios (composting, recycling, and upcycling) were evaluated in terms of literature review. As a result, the ability of bioplastics to be biodegraded by composting has been related to physical variables and materials characteristics. Hence, it is possible to deduce that the process is mature enough to be a good way to minimize bioplastic waste and valorize it for the production of a fertilizer. Recycling and upcycling options, which could open up many interesting new scenarios for the production of high-value materials, are less studied. Research in this area can be strongly encouraged.

The proof of concept for a new copolymerization approach taking advantage of the thermally reversible aptitude of the furan/maleimide Diels–Alder (DA) adducts is reported here. A new monomer bearing two carboxylic acids as end‐groups and a Diels–Alder adduct within its structure is synthesized using benign and mild reaction conditions. Two polyesters are then fabricated from the DA‐diacid and 1,6‐hexanediol and 1,4‐benzenedimethanol, respectively, and characterized by 1H‐NMR, GPC, DSC, and TGA. Kinetic studies of these polyesters, performed by 1H‐NMR spectroscopy at variable temperatures, establish the appropriate conditions for their controlled depolymerization, through the retro Diels–Alder reaction (rDA), and their re‐construction through the DA reaction, showing moreover the reproducibility of this rDA/DA cycle. Finally, by exploiting this peculiar feature, a copolyester is successfully synthesized from the concomitant treatment of the two homopolymers, demonstrating the effectiveness of the method. The present approach provides a new method for the fabrication of multicomponent copolymers based on the DA/rDA strategy that is extendable to a variety of other polycondensation materials, such as polyesters, polyamides, polyurethanes, and epoxies, allowing the establishment of a library of novel architectures through this one‐pot approach.

The dynamic and equilibrium water vapor sorption properties of amorphous and highly crystalline poly(ethylene vanillate) (PEV) films were determined via gravimetric analysis, at 20 °C, over a wide range of relative humidity (0–95% RH). At low RH%, the dynamic of the sorption process obeys Fick’s law while at higher relative humidity it is characterized by a drift ascribable to non-Fickian relaxations. The non-Fickian relaxations, which are responsible for the incorporation of additional water, are correlated with the upturn of the sorption isotherms and simultaneously the hysteresis recorded between sorption and desorption cycles. The sorption isotherms of amorphous and highly crystalline PEV are arranged in the same concentration range of that of PET proving the similarity of the two polyesters. Water diffusion coefficients, whose determination from individual kinetic sorption/desorption curves required treatment with the Barens–Hopfenberg model, were demonstrated to be ≈ 10× higher for amorphous PEV compared to amorphous PET. Such a difference originates from the enhanced segmental flexibility of PEV chains.

A new building block, derived from dimethyl itaconate, has been synthesized through thia-Michael addition reaction and then exploited for the synthesis of a series of novel aliphatic polyesters. The new monomer, the dimethyl 2-((octylthio)methyl)succinate, demonstrated a remarkable stability toward common conditions of polycondensation (high temperatures and metal-based catalysts) and was suitable for polycondensation reactions with different diols. The resulting polyesters are characterized by high molecular weights and good stability; they are amorphous polymers with a tunable glass transition temperature depending on the rigidity of the diol. The synthetic approach presented here allows, for the first time, remarkably stable polymeric structures based on itaconic acid, circumventing its inherent thermal lability, to be achieved. Furthermore, by demonstration of the successful exploitation of thia-Michael adducts in polymer science, the bases have been set for the creation of a novel renewable platform based on dimethyl itaconate.

Poly(lactide)/poly(-caprolactone) blends (PLA/PCL) with composition 80/20 (w/w%) are immiscible but biodegradable and therefore often studied in the literature. We have prepared 80/20 PLA/PCL blends with and without poly(ε-caprolactone)-co-poly(carbonate) copolymers (block and random). The blends were prepared both by melt extrusion and by solution blending. The concentration of PCL-co-PC copolymers added to the blends was 2 wt%. Compression molded sheets and solvent cast films were evaluated by GPC (Gel Permeation Chromatography), TGA (Thermogravimetric Analysis), SEM (Scanning Electron Microscopy), PLOM (Polarized Light Optical Microscopy) and DSC (Differential Scanning Calorimetry). Copolymer addition causes a reduction of molecular weight in melt mixed blends. In particular, the random copolymer (PCL-ran-PC) causes the highest molecular weight reduction, since it has lower thermal stability, as shown by TGA. PLOM experiments show that these degraded PLA chains in melt-mixed blends can nucleate and grow faster than similar but undegraded PLA chains in solution-mixed blends. As a result, the PLA phase within melt mixed blends containing PCL-co-PC copolymers shows a higher tendency to crystallize during both isothermal and non-isothermal DSC experiments. Upon molecular weight reduction in melt mixed blends containing copolymers, PLA chains have a higher mobility resulting in faster diffusion towards the growing crystal front. Our results show crystallization kinetic measurements, performed by PLOM or DSC, are useful tools to qualitatively detect molecular weight changes produced by degradation of PLA chains, when the molecular weight reduction is not large enough to decrease Tm values.