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Incorporating reprocessing, recycling, and sustainable processes and materials is essential for a circular economy. Reprocessing and recycling are related since both help minimize wastage and produce a sustainable regenerative economy. However, polymers might undergo degradation depending on the recycling process, reducing their lifespan. In this study, polybutylene adipate terephthalate (PBAT) undergoes repetitive reprocessing under varied temperatures, times, and shear rates to investigate the evolution of mechanical, chemical, and thermal properties. Furthermore, foaming experiments are conducted using supercritical carbon dioxide (scCO2) on reprocessed samples to examine changes in the properties and morphology of the foam. The significance of reprocessing PBAT is divided into environmental, temperature, and processing effects. Environmental conditions impact the results where no oxidation effects are noticed in the 2‐hour test, while 7 days of humidity exposure lead to a tenfold reduction in polymer viscosity. Different processing techniques reduce the molecular weight of PBAT and alter its polydispersity. Specifically, the number average molecular weight (Mn) decreases from an initial 53 to 37 kDa after processes like extrusion or mixing. However, elongation at break and ultimate strength of PBAT remain unchanged after high‐shear extrusion processing. Additionally, PBAT foam morphology evolves over 5 cycles, leading to smaller pores and reducing compressive modulus. [ABSTRACT FROM AUTHOR]

In the present work, we demonstrate that zero‐shear viscosity is a sensitive rheological function to detect phase inversion in immiscible binary polymer blends characterized by a viscosity ratio larger than one. The phase inversion of poly(propylene) (PP)/low‐density poly(ethylene) (LDPE) and poly(styrene) (PS)/LDPE, at various compositions, was assessed via our novel approach. For both blends, three distinctive regions could be determined through zero‐shear viscosity measurements; the LDPE matrix, the co‐continuous phase, and the PS or PP matrix. For PP/LDPE blends, the co‐continuous structure was between 50 and 75 wt.% PP, and for PS/LDPE blends the co‐continuous structure was between 45 and 75 wt.% PS, in agreement with scanning electron microscopy analysis, empirical model predictions, and literature data. Highlights: Phase inversion revealed via viscosity measurements.Limitations of linear viscoelastic models for immiscible blends assessed. [ABSTRACT FROM AUTHOR]

Plastic pollution poses a significant environmental challenge, necessitating the investigation of bioplastics with reduced end-of-life impact. This study systematically characterizes four promising bioplastics—polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and polylactic acid (PLA). Through a comprehensive analysis of their chemical, thermal, and mechanical properties, we elucidate their structural intricacies, processing behaviors, and potential morphologies. Employing an environmentally friendly process utilizing supercritical carbon dioxide, we successfully produced porous materials with microcellular structures. PBAT, PBS, and PLA exhibit closed-cell morphologies, while PHBV presents open cells, reflecting their distinct overall properties. Notably, PBAT foam demonstrated an average porous area of 1030.86 μm2, PBS showed an average porous area of 673 μm2, PHBV displayed open pores with an average area of 116.6 μm2, and PLA exhibited an average porous area of 620 μm2. Despite the intricacies involved in correlating morphology with material properties, the observed variations in pore area sizes align with the findings from chemical, thermal, and mechanical characterization. This alignment enhances our understanding of the morphological characteristics of each sample. Therefore, here, we report an advancement and comprehensive research in bioplastics, offering deeper insights into their properties and potential morphologies with an easy sustainable foaming process. The alignment of the process with sustainability principles, coupled with the unique features of each polymer, positions them as environmentally conscious and versatile materials for a range of applications. [ABSTRACT FROM AUTHOR]

A solvent-free route of initiated chemical vapor deposition (iCVD) was used to synthesize a bio-renewable poly(α-Methylene-γ-butyrolactone) (PMBL) polymer. α-MBL, also known as tulipalin A, is a bio-based monomer that can be a sustainable alternative to produce polymer coatings with interesting material properties. The produced polymers were deposited as thin films on three different types of substrates—polycarbonate (PC) sheets, microscopic glass, and silicon wafers—and characterized via an array of characterization techniques, including Fourier-transform infrared (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), ultraviolet visible spectroscopy (UV–vis), differential scanning calorimetry (DSC), size-exclusion chromatography (SEC), and thermogravimetric analysis (TGA). Optically transparent thin films and coatings of PMBL were found to have high thermal stability up to 310 °C. The resulting PMBL films also displayed good optical characteristics, and a high glass transition temperature (Tg~164 °C), higher than the Tg of its structurally resembling fossil-based linear analogue-poly(methyl methacrylate). The effect of monomer partial pressure to monomer saturation vapor pressure (Pm/Psat) on the deposition rate was investigated in this study. Both the deposition rate and molar masses increased linearly with Pm/Psat following the normal iCVD mechanism and kinetics that have been reported in literature. [ABSTRACT FROM AUTHOR]