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Food contact materials (FCM) polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) used extensively in food packaging may contain cyclic oligomers which may migrate into food and thus cause toxic effects on human health. A simple, fast, and sensitive ultra-high-performance liquid chromatography method quadrupole time-of-flight mass spectrometer was developed for the analysis of 7 cyclic oligomers in post-mortem blood samples. The targeted analytes were separated on a Waters BEH C18 (150 × 2.1 mm, 1.7 µm) analytical column by gradient elution. Calibration curves were constructed based on standard solutions and blood samples and Student’s t-test was applied to evaluate the matrix effect. The LODs ranged from 1.7 to 16.7 μg mL−1, while the method accuracy was assessed by recovery experiments and resulting within the range 84.2–114.6%. Such an analytical method for the determination of PET and PBT cyclic oligomers in biological samples is reported for the first time. The developed methodology allows the determination of these oligomers in blood providing a useful analytical tool to assess the exposure and thus the potential hazard and health risks associated with these non-intentionally added substances (NIAS) from PET and PBT FCM through food consumption. The method was validated and successfully applied to the analysis of 34 post-mortem whole blood samples. Polyethylene terephthalate trimer was detected in four of them, for the first time in literature.

Biodegradable polylactic acid (PLA) has been widely used in fused deposition modeling (FDM) 3D printing. In order to improve its comprehensive properties in 3D printing, in this study, 0-40% content of polybutylene adipate terephthalate(PBAT) was selected to be blended with PLA in a twin-screw extruder; the resulting pellets were drawn into a homogeneous filament; then, PBAT/PLA samples were prepared by FDM 3D printing, and the effects of the dosage of PBAT on the mechanical properties, thermal behavior, surface wettability and melt flowability of the samples were investigated. The results showed that all the samples could be printed smoothly, and the ductility was slightly improved by the increase in the PBAT dosage; the thermal stability of PLA was enhanced by blending with PBAT, and the crystallinity increased monotonically with the increase in PBAT. After blending with PBAT, the surfaces of the samples were more hydrophilic and flowable. The important conclusion achieved in this work was that the PBAT/PLA blends, especially those containing 30%PBAT, showed great potential to replace petroleum-based plastics and are suitable for use in FDM 3D printing technologies for different applications.

Polybutylene succinate (PBS) stands out as a promising biodegradable polymer, drawing attention for its potential as an eco-friendly alternative to traditional plastics due to its biodegradability and reduced environmental impact. In this study, we aimed to enhance PBS degradation by examining artificial consortia composed of bacterial strains. Specifically, Terribacillus sp. JY49, Bacillus sp. JY35, and Bacillus sp. NR4 were assessed for their capabilities and synergistic effects in PBS degradation. When only two types of strains, Bacillus sp. JY35 and Bacillus sp. NR4, were co-cultured as a consortium, a notable increase in degradation activity toward PBS was observed compared to their activities alone. The consortium of Bacillus sp. JY35 and Bacillus sp. NR4 demonstrated a remarkable degradation yield of 76.5% in PBS after 10 days. The degradation of PBS by the consortium was validated and our findings underscore the potential for enhancing PBS degradation and the possibility of fast degradation by forming artificial consortia, leveraging the synergy between strains with limited PBS degradation activity. Furthermore, this study demonstrated that utilizing only two types of strains in the consortium facilitates easy control and provides reproducible results. This approach mitigates the risk of losing activity and reproducibility issues often associated with natural consortia.

Biodegradable plastics applied to soil stimulate the production of greenhouse gases and inhibit plant growth under aerobic conditions. This study aimed to examine the effects of biodegradable plastics on paddy rice growth and greenhouse gas emission under flooding conditions in pot experiments and also on greenhouse gas production under flooding conditions in an incubation experiment. Two series of pot experiments were conducted with rice (Oryza sativa). First series as immediate flooded and 2nd series as 2 weeks nonflooding before flooded, and both kept flooded until harvest. The following four kinds of materials were added to the sandy paddy soil, (1) nonwoven fabric sheets made of polylactic acid and polybutylene-succinate, (2) laminate sheets made of polybutylene adipate terephthalate and pulp, (3) cellulose filter paper, and (4) rice straw. Only soil was used as control. Methane (CH4) emission, measured by chamber method followed by gas chromatography, was significantly larger only in the cellulose treatment than the laminate treatment in the immediate flooded series, indicating that biodegradable plastics had no significant impact on CH4 emission from paddy rice soil. Rice growth and yield did not show significant difference among treatments in both series. Incubation experiment showed the largest CH4 production in cellulose-amended soil, followed by straw-amended and laminate amended soils, and least in fabric-amended soil, while CO2 did not show significant differences among treatments. We need further examination with different biodegradable plastics for a longer period that test used in this study.

The need for utilization of environmentally friendly materials has emerged due to environmental pollution that is caused by non-biodegradable materials. The usage of non-biodegradable plastics has increased in the past decades in many industries, and, as a result, the generation of non-biodegradable plastic wastes has also increased. To solve the problem of non-biodegradable plastic wastes, there is need for fabrication of bio-based polymers to replace petroleum-based polymers and provide strategic plans to reduce the production cost of bioplastics. One of the emerging bioplastics in the market is poly (butylene succinate) (PBS) and it has been the biopolymer of choice due to its biodegradability and environmental friendliness. However, there are some disadvantages associated with PBS such as high cost, low gas barrier properties, and softness. To lower the cost of PBS and enhance its properties, natural lignocellulosic fibers are incorporated into the PBS matrix, to form environmentally friendly composites. Natural fiber-based biocomposites have emerged as materials of interest in important industries such as packaging, automobile, and construction. The bonding between the PBS and natural fibers is weak, which is a major problem for advanced applications of this system. As a result, this review paper discusses various methods that are employed for surface modification of the Fibers The paper provides an in-depth discussion on the preparation, modification, and morphology of the natural fiber-reinforced polybutylene succinate biocomposites. Furthermore, because the preparation as well as the modification of the fiber-reinforced biocomposites have an influence on the mechanical properties of the biocomposites, mechanical properties of the biocomposites are also discussed. The applications of the natural fiber/PBS biocomposites for different systems are also reported.

The widespread use of conventional plastics in various industries has resulted in increased oil consumption and environmental pollution. To address these issues, a combination of plastic recycling and the use of biodegradable plastics is essential. Among biodegradable polymers, poly butylene adipate-co-terephthalate (PBAT) has attracted significant attention due to its favorable mechanical properties and biodegradability. In this study, we investigated the potential of using PBAT for direct pellet printing, eliminating the need for filament conversion. To determine the optimal printing temperature, three sets of tensile specimens were 3D-printed at varying nozzle temperatures, and their mechanical properties and microstructure were analyzed. Additionally, dynamic mechanical thermal analysis (DMTA) was conducted to evaluate the thermal behavior of the printed PBAT. Furthermore, we designed and printed two structures with different infill percentages (40% and 60%) to assess their compressive strength and energy absorption properties. DMTA revealed that PBAT’s glass–rubber transition temperature is approximately −25 °C. Our findings demonstrate that increasing the nozzle temperature enhances the mechanical properties of PBAT. Notably, the highest nozzle temperature of 200 °C yielded remarkable results, with an elongation of 1379% and a tensile strength of 7.5 MPa. Moreover, specimens with a 60% infill density exhibited superior compressive strength (1338 KPa) and energy absorption compared with those with 40% infill density (1306 KPa). The SEM images showed that with an increase in the nozzle temperature, the quality of the print was greatly improved, and it was difficult to find microholes or even a layered structure for the sample printed at 200 °C.

The aim of this study is to clarify the deflection, splaying, and abrasion of single tufts of polybutylene terephthalate (PBT) toothbrushes after use. A single-center randomized controlled trial is performed. The changes in deflection, bristle splaying, and abrasion are investigated for the middle single tuft of the top line (top–middle tuft) and the middle single tuft of the bottom line (bottom–middle tuft) of PBT toothbrushes with medium stiffness after 1 month, 2 months, and 3 months of use by 34 participants. A soft-material bending-resistance tester is used to assess the deflection of the single tufts. The deflection value of the top–middle tuft significantly increased after 1 month of use compared with the baseline. In contrast, the deflection of the bottom–middle tuft significantly increased after 3 months of use compared with the baseline and after 1 month and 2 months of use. Importantly, the change in deflection was distinctly different between the top– and bottom–middle tufts. The bristle splaying of both tufts significantly increased after use, but a significant change in bristle abrasion was not found. The bending stiffness of the top tuft of a PBT toothbrush may decrease more rapidly than that of the bottom tuft with use.

Microplastic pollution has been widely studied in the marine environment, but is much less explored in terrestrial waters, notably in China. Therefore, we studied the degree of microplastic pollution in surface waters of Lake Ulansuhai, a major freshwater lake in the Yellow River basin of northern China. Results show microplastic concentrations ranging from 1760 ± 710 to 10,120 ± 4090 n/m3. The microplastic spatial distribution is heterogeneous, with higher levels near the drainage canal entrance of Lake Ulansuhai, and a downward trend from north to south in the lake. The main type of microplastics is colored particles, including fibers as the most abundant. More than 80% of microplastics were smaller than 2 mm. FTIR analysis results show that the main plastics were polyethylene, polystyrene and polybutylene terephthalate. There were also some metallic elements adsorbed on the surface of microplastics, such as Fe, Ca and Zn, detected by energy-dispersive spectrometry. The presence of metallic elements may worsen water pollution.

The current work is driven by applying circular principles, and it investigated the potential recyclability of polybutylene succinate (PBS) containing brewer’s spent grain filler (BSGF, 30 wt%) in comparison to the recyclability of pure PBS. PBS is much more stable than the PBS/BSGF composite during processing cycles. Typically, thermomechanical degradation induces radical formation and branching of the macromolecular chain in PBS. Furthermore, PBS becomes less hydrophilic (by 53%, reaching 84°, approaching the 90° threshold), and its surface roughness increases by about 38% after five processing cycles. BSGF increases the viscosity of the melt, especially at low frequencies, and stabilizes the melt in the PBS/BSGF, which has lower torque variations during processing compared to pure PBS. Furthermore, BSGF in r-PBS/BSGF increases both hydrophilicity (by about 15%, from 75° to 64°) and surface roughness (by about 17%) after five processing cycles of the solid bio-composite and limits the formation of carboxylic groups during thermomechanical degradation. PBS is recyclable five times because it maintains its properties unchanged during extrusion cycles. At least two reprocessing steps are required for PBS/BSGF to obtain an optimal dispersion of BSGF, which can be re-extruded approximately three times. PBS/BSGF after four and five extrusion steps shows increased rigidity (Et PBS/BSGF > Et PBS) and reduced ductility (εb PBS/BSGF < εbt PBS), which could limit the recyclability of the PBS-based composite.

This research aimed to prepare nonwovens from polylactic acid and polybutylene succinate using the melt-blown process while varying the melt-blown process parameters, including air pressure (0.2 and 0.4 MPa) and die-to-collector distance (15, 30, and 45 cm). Increasing the air pressure and die-to-collector distance resulted in the production of smaller fibers. Simultaneously, the tensile strength was dependent on the polymer, air pressure, and die-to-collector distance used, and the percentage elongation at the break tended to increase with an increasing die-to-collector distance. Regarding thermal properties, the PBS nonwovens exhibited an increased level of crystallinity when the die-to-collector distance was raised, consistent with the degree of crystallinity obtained from X-ray diffraction analysis. Polylactic acid could be successfully processed into nonwovens under all six investigated conditions, whereas nonwoven polybutylene succinate could not be formed at a die-to-collector distance of 15 cm. However, both polymers demonstrated the feasibility of being processed into nonwovens using the melt-blown technique, showing potential for applications in the textile industry.