The growing issue of non-degradable plastic waste has spurred the search for sustainable alternatives, with starch appearing as a promising bioplastic material due to its renewability, low cost, and biodegradability. This study focused on developing environmentally friendly films by combining starch−curcumin (SC) complexes with polyvinyl alcohols (PVA). The films were made by solvent casting and involved varying the amount of curcumin for the starch complexation, the mass ratio of the starch complexes and PVA, and the number of plasticizers. The resulting films were yellow-orangish. The films were characterized to assess their mechanical properties, hydrophilicity, swelling degrees, and surface topography. The films were further evaluated to study their properties upon storage at room temperature, exposure to solutions with different acidities, and soil burial test. The results showed that adding PVA increased the films’ crystallinities and mechanical properties. Higher curcumin and PVA contents produced films with less hydrophilicity and reduced swelling degree. The films changed color in response to pH, such as turning yellow at pH 4 and darker orange at pH 9. This indicated its potential as an innovative packaging related to pH change, such as detecting food spoilage. In addition, the soil burial test of the films revealed mass reduction (50-85% after 7 days), with a higher amount of SC complexes resulting in faster mass loss. This showed that the films had a high potential as sustainable and functional biodegradable plastics.

Mitigating climate change and promoting sustainability involves reducing energy consumption, especially in key sectors such as construction and transportation. Achieving this goal requires materials with enhanced performance, greater thermal efficiency, lower density, and improved mechanical properties.

Nanocellular polymers are biphasic materials consisting of a polymeric solid matrix and a gaseous phase at the nanometric scale. The presence of such small pores results in confinement effects in both phases. On the one hand, air molecules are restricted within the nanometric pores, while polymer chains are confined within the solid nanostructure. This confinement has been shown to enhance these materials' thermal conductivity, mechanical strength, and optical properties compared to conventional cellular polymers with larger pores, and even to the solid polymer itself.

This study highlights the real potential of nanocellular polymers based on polymers such as polyetherimide, polymethylmethacrylate, polystyrene, or polylactic acid, in promoting sustainability across key sectors such as construction and transportation. The thermal, mechanical, and optical properties of these advanced materials have been evaluated and compared with those currently available.

One of the major obstacles in plastic waste recycling is contamination by organic substances such as oils, acids, fats, and detergents. These contaminants cannot be completely removed from the bulk of the polymer by washing with water, often preventing recycled plastics from meeting the stringent requirements for high demanding applications, including food-contact materials, packaging, household devices, and toys.
Supercritical carbon dioxide (scCO₂) is a well-known green solvent for many organic compounds and does not interact in a detrimental way with most thermoplastic polymers. This makes it a promising extraction medium for decontaminating plastic waste. In this study, we demonstrate the application of supercritical CO₂ extraction using two case studies [1, 2]:
High-Density Polyethylene (HDPE) – a widely produced commodity polymer used in packaging.
Polyvinylidene Fluoride (PVDF) – a high-performance thermoplastic with broad applications in the oil and gas as well as chemical industry, and battery manufacturing.
We investigate the effects of process parameters on extraction kinetics and yield. For HDPE, decontamination efficacy is assessed by measuring polyaromatic hydrocarbon (PAHs) levels before and after extraction, as these carcinogenic substances pose a significant barrier to closed-loop recycling. Finally, we discuss the advantages and limitations of the method, highlighting its potential through these case studies.

Poly(lactic acid) and poly(hydroxyalkanoates) are promising sustainable biopolymers employed for packaging applications. Their production costs as well as the material performances are often not comparable to conventional polymers already in use[1]. To overcome these limitations, a possible solution is to design composite materials made of biopolymer loaded with natural fillers. Milled and stabilized pasta residues as well as orange peel powder were tested as sustainable fillers. Chemical, mechanical, and thermo-mechanical properties of the composite materials were assessed. Also, the processability of the materials was investigated, by developing protocols for different processes such as extrusion, injection molding, thermoforming, filament production, and 3D-printing. The use of natural compatibilizers and plasticizers to improve the mechanical properties and processability was also evaluated. To proceed with conventional twin-screw extrusion compounding, pasta residues and orange peel powder were sieved and stabilized with different thermal treatments, to reduce the moisture content. The use of up to 10 wt.% of filler did not affect the processability of the material. Also, Fourier Transformed Infrared Spectroscopy (FTIR) demonstrated that no variation of the typical molecular spectra of the polymers could be observed in the composite material.
The authors wish to acknowledge financial support of the Project funded under the National Recovery and Resilience Plan (NRRP), Mission 04 Component 2 Investment 1.5 - NextGenerationEU, Call for tender n. 3277 dated 30/12/2021, Award Number: 0001052 dated 23/06/2022.

Bio-based and biodegradable polymers, sustainable alternatives to traditional petroleum-based polymers, are interesting materials because able to positively contribute to the current environmental concerns in terms of the plastic pollution and greenhouse gas emissions. In this regard, poly (lactide) (PLA) has been and is widely used due to its biodegradability, biocompatibility and quite low cost.
To improve its mechanical and barrier properties, various modification techniques have been utilized, as for example incorporation of nano-sized fillers to produce nanocomposites. Owing to their nanoscale dimensions, the polymer/nanofiller interphase represents a significant volume fraction even at low filler concentrations [1].
In this regard, the major challenges to develop PLA-based nanocomposites for advanced technological applications is the capacity to understand the structure and properties of the interphase between the polymer and nanofiller. The present study contributes to a better knowledge and understanding of the role that the nano-sized interphases (at the amorphous/crystal and at the amorphous/filler boundaries) can have on the mechanical and barrier properties of PLA nanocomposites.
Various nanofillers have been used for the preparation of PLA nanocomposites by extrusion. Thermal, mechanical, viscoelastic, barrier properties have been evaluated. The aim of the study has been to identify how the various macroscopic properties are differently influenced by different nanofillers.


The work has been funded by European Union (NextGenerationEU) (PNRR - M4, C2, I1.1) through the PRIN 2022 project AMOR-BIO (2022S2Z9XP)