Poly Butylene Adipate Co-terephthalate Research Articles

Near-Surface Reconfiguration of Biopolymer Blends by Mechanical Embossment: Creation of Friction-Reduced Foils

Biopolymer blends of polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT) are extruded into flexible monolayer films. These blends are excellent candidates for the realization of environmentally friendly packaging applications. A necessary pre-requisite for that are appropriate tribological properties under mechanical contact. Reasonable wear resistance allows good protection of packed goods, and low friction forces reduce difficulties in stacking. In this research, mechanical embossment under high loads at room temperature was used for the modification of polymer surfaces to exhibit a significant friction reduction under dry conditions. The results particularly show a systematic decrease in the coefficient of friction for biopolymer blends containing 30 wt% and 40 wt% PBAT. FTIR was used to analyze the change in surface composition after mechanical embossing. A sophisticated FTIR calibration method revealed that the blend with 30 wt% PBAT shows a modified distribution of PBAT and PLA at the surface due to mechanical embossment. This leads to a controlled and long-lasting modification of the surface properties without a substantial change in the chemical composition of the polymer in bulk. Without the use of additional coatings, biodegradable packaging foils with improved characteristics are accessible.

Effects of Microplastics on Soil N2O Emission and Nitrogen Transformations from Tropical Agricultural Soils

A widespread concern had been there regarding soil ecological and environmental problems caused by microplastic pollution in agricultural soils. A controlled laboratory incubation experiment was performed to examine the effects of different types of microplastics on soil properties, N2O emissions, and nitrogen （N） transformations in tropical arable soils from a pepper-corn cropping system in Hainan Province. Three treatments were done： soil without microplastics （CK） and soil amended with 5% of polyethylene （PE） or with 5% of polybutylene adipate co-terephthalate （PBAT）. The results showed that both types of microplastic addition increased soil pH, soil organic carbon （SOC）, and dissolved organic carbon （DOC） contents, with stronger treatment effects observed for PBAT than those for the PE treatment. In addition, the PE and PBAT treatments increased soil ammonium nitrogen （NH4+-N） contents by 66.07% and 119.65% and decreased nitrate nitrogen （NO3--N） contents by 8.56% and 29.68%, respectively. Compared to those in the CK treatment, the addition of PBAT significantly increased soil N2O emissions by 254.92% （P < 0.05）, whereas that of PE produced no significant effects. Furthermore, both the PE and PBAT treatments increased soil net nitrogen mineralization rate （NMR） and decreased soil net nitrification rate （NNR）, with more obvious treatment effects observed in PBAT than in the PE treatment. PBAT addition increased the abundance of ureC, while PE had no significant effects. Microplastic addition reduced the abundance of nitrifying gene abundances （AOA-amoA, AOB-amoA, and nxrA）, with more obvious treatment effects found in the PBAT treatment. Further, PBAT addition significantly increased the gene abundances of nirK, nirS, nosZ, and fungal nirK （P < 0.05）, whereas the addition of PE had no significant effect on those gene abundances. Soil N2O emissions had positive relationships with NH4+-N intensity, pH, DOC, SOC, and nirS abundance. In conclusion, biodegradable microplastics addition produced stronger influences on soil properties and N transformations than the non-biodegradable one in tropical arable soils and aggravated soil N2O emissions mainly by promoting denitrification.

Enhancing soil gross nitrogen transformation through regulation of microbial nitrogen-cycling genes by biodegradable microplastics

Microplastics (MPs) in agricultural plastic film mulching system changes microbial functions and nutrient dynamics in soils. However, how biodegradable MPs impact the soil gross nitrogen (N) transformations and crop N uptake remain significantly unknown. In this study, we conducted a paired labeling 15N tracer experiment and microbial N-cycling gene analysis to investigate the dynamics and mechanisms of soil gross N transformation processes in soils amended with conventional (polyethylene, PE) and biodegradable (polybutylene adipate co-terephthalate, PBAT) MPs at concentrations of 0 %, 0.5 %, and 2 % (w/w). The biodegradable MPs-amended soils showed higher gross N mineralization rates (0.5–16 times) and plant N uptake rates (16–32 %) than soils without MPs (CK) and with conventional MPs. The MPs (both PE and PBAT) with high concentration (2 %) increased gross N mineralization rates compared to low concentration (0.5 %). Compare to CK, MPs decreased the soil gross nitrification rates, except for PBAT with 2 % concentration; while PE with 0.5 % concentration and PBAT with 2 % concentration increased but PBAT with 0.5 % concentration decreased the gross N immobilization rates significantly. The results indicated that there were both a concentration effect and a material effect of MPs on soil gross N transformations. Biodegradable MPs increased N-cycling gene abundance by 60–103 %; while there was no difference in the abundance of total N-cycling genes between soils without MPs and with conventional MPs. In summary, biodegradable MPs increased N cycling gene abundance by providing enriched nutrient substrates and enhancing microbial biomass, thereby promoting gross N transformation processes and maize N uptake in short-term. These findings provide insights into the potential consequences associated with the exposure of biodegradable MPs, particularly their impact on soil N cycling processes.

Effects of biodegradable microplastics coexistence with biochars produced at low and high temperatures on bacterial community structure and phenanthrene degradation in soil

The increasing use of biodegradable plastics may result in more serious pollution of microplastics which often coexist with biochar in soil, this will affect how organic pollutants move and transform in the soil. This work investigated the effect of biodegradable polybutylene adipate-co-terephthalate (PBAT) coexistence with biochars produced at temperatures of 400 and 700 °C (W4 and W7) on soil bacterial communities and phenanthrene degradation. The results showed that coexistence of PBAT and biochar paticles greatly boosted the relative abundance of Nocardioides while decreased the relative abundance of Sphingomonas as compared to soils with a single addition of PBAT or biochar. Changes in soil Eh values were the most influential factor in bacterial communities (more than 40% contribution). The degradation ratio of phenanthrene when PBAT coexisted with W7 (39.6 ± 3.6%) was not significantly different from the treatment with a single W7 addition (35.0 ± 2.3%, P＞0.05), and was related to phenanthrene degradation in the adsorbed state of W7 in soil. In contrast, the degradation ratio of phenanthrene in PBAT coexisting with W4 (35.1 ± 3.5%) was intermediate between that of single PBAT (49.8 ± 0.9%) and W4 (13.7 ± 5.8%) treatments. This was primarily due to changes in the experiment's initial bioavailable phenanthrene content. Furthermore, after the introduction of earthworms, phenanthrene degradation ratio in coexistence treatments were very similar to that described above in the absence of earthworms. Except for two treatments that contain W7, phenanthrene degradation ratio in the other treatments was increased by the presence of earthworms (up to 23%), which is related to the enhanced relative abundance of polycyclic aromatic hydrocarbon-degraders. Our findings indicated that PBAT coexistence with high-temperature or low-temperature biochar had a completely different impact on bacterial communities and phenanthrene degradation in soil.

Technoeconomic Analysis for Biodegradable and Recyclable Paper Coated with Synthetic Ionic PBAT for Packaging Application.

This study presents a technoeconomic analysis (TEA) for a novel ionic polybutylene adipate-co-terephthalate (PBAT), CPBAT, as a paper coating material, showcasing excellent water and oil resistance. This TEA determined total capital investment, operating costs, and minimum selling prices for a production capacity of 1,000 kg of CPBAT per day. The minimum selling prices of CPBAT coated on Kraft paper (CPBAT-K) and CPABT coated on starch-coated Kraft paper (CPBAT-S) are estimated to be $1.327/m2 and $1.864/m2, respectively. Additionally, the results of a sensitivity analysis show that the production of CPBAT-K and CPBAT-S is highly sensitive to the production capacity, raw material costs, energy efficiency of the coating process, reaction energy, and reaction yield. Recovery of the ionization solvent only marginally increases the selling prices of CPBAT-K and CPBAT-S, and hence, it is highly favorable. By increasing production capacity, lowering raw material costs, using energy-efficient coating machines, and partially recovering energy from reactions, the prices of CPBAT-K and CPBAT-S can be reduced to $0.588/m2 and $0.914/m2, respectively. Given that commercial polyethylene-coated paper prices range from $0.94/m2 to $1.850/m2, CPBAT-based coated papers with comparable mechanical and barrier properties along with biodegradability and recyclability are positioned as highly competitive and sustainable alternatives in the market.

A Fully Biodegradable and Ultra‐Sensitive Crack‐Based Strain Sensor for Biomechanical Signal Monitoring

AbstractA fully biodegradable, ultra‐sensitive, and soft strain sensor is pivotal for temporary, real‐time monitoring of microdeformations, crucial in disease diagnosis, surgical precision, and prognosis of muscular, and vascular conditions. Nevertheless, the strain sensitivity of previous biodegradable sensors, denoted by gauge factor (GF) up to ≈100, falls short of requirements for complex biomedical monitoring scenarios, specifically monitoring cardio‐cerebrovascular diseases with microscale variations in vascular surface strain. Here, a fully biodegradable, ultra‐sensitive crack‐based flexible strain sensor is introduced achieving GF of 1355 at 1.5% strain through integration of molybdenum (Mo) film, molybdenum trioxide (MoO3) adhesion layer, and polycaprolactone (PCL) substrate. Analysis of crack morphology of biodegradable thin‐film metals, including Mo, tungsten (W), and magnesium (Mg), reveals material‐dependent sensitivity and repeatability of crack‐based strain sensors. The effect of the adhesion layer and polymer substrate is also investigated. Overall morphological studies on the sensor present a comprehensive understanding of metal film cracking behavior and corresponding performance characterization, showing significant potential for highly sensitive sensors. A hybrid membrane composed of candelilla wax (Cw), beeswax (Bw), and polybutylene adipate‐co‐terephthalate (PBAT) is introduced to provide hydrophobic, yet flexible encapsulation. In vivo, short‐term (≈3 days) monitoring of vascular pulsatility underscores the potential of the sensing tool for rapid, accurate, and temporal disease diagnosis and treatment.

PBAT microplastics exacerbates N2O emissions from tropical latosols mainly via stimulating denitrification

Biodegradable plastic mulching films are regarded as promising substitutes for their non-degradable counterparts to ameliorate serious plastic pollution in agriculture. Inevitably, biodegradable microplastics (BMs) can be formed and profoundly affect the function of soil ecosystems. However, little is known about the effects of BMs loading on soil nitrogen (N) dynamics and loss in tropical agricultural soils. Hereby, a 120-day soil incubation trial was performed to evaluate the effects of polybutylene adipate co-terephthalate (PBAT) microplastics on nitrous oxide (N2O) emissions, N transformation, and bacterial community structure in latosols. The results showed that PBAT addition raised soil ammonium nitrogen (NH4+–N) and dissolved organic carbon (DOC) contents, but lowered nitrate nitrogen (NO3––N) contents, accompanied with a smaller potential nitrification rate and a greater potential denitrification rate. The microbial biomass nitrogen and nrfA gene abundance were increased by PBAT, suggesting the processes of microbial N immobilization and dissimilatory nitrate reduction to ammonia were largely promoted. Positive correlations existed between N2O emissions and denitrification-related enzymatic activities and functional gene abundances (narG, nirK/S and Fungal nirK). PBAT amendment stimulated N2O emissions by 54.8 − 317.3 %, accompanied with increased values of those denitrification-related parameters, suggesting that stimulated denitrification was responsible for the exacerbated N2O emissions. Moreover, PBAT addition changed bacterial alpha diversity and bacterial community composition, where the relative abundances of Proteobacteria increased while those of Nitrospirae and Acidobacteria decreased. These findings are beneficial to understanding the fate of N in microplastics-polluted soil, which will provide a new insight into the impact of BMs on soil functions and environmental risks.

Poly(butylene adipate-co-terephthalate)/thermoplastic canna starch (Canna edulis ker.) (PBAT/TPS) blend film – A novel biodegradable material

The PBAT (poly (butylene adipate-co-terephthalate) is a promising biodegradable material. However, it is often blend with hydrophilic polymers since its degradation rate in the aquatic environment is still limited. In this study, the blend PBAT/TPS (thermoplastic starch) films, namely BFs, were prepared by a blow extrusion approach, and evaluated for hydrolysis in four studied mediums acid (HCl, 1 M, 2 M, and 3 M), alkaline (NaOH, pH = 9, 11, and 13), phosphate buffer (pH = 7.4), and artificial seawater. The hydrolyzed BFs were characterized by weight loss, mechanical properties, scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and differential scanning calorimetry (DSC). A larger starch content in the BFs caused hydrolysis more quickly. The highest hydrolytic rate was found in the alkaline solution, followed by the acid medium. The complete abiotic hydrolysis of the BFs was 3 M HCl for 14 days or NaOH (pH 13) for 35 days. After 180 days of incubation, the film containing 70.5 % PBAT/TPS granules has been associated with the highest biodegradation rate of 76.31 % in composting.

Continuous co-digestion of sewage sludge and highly concentrated waste bioplastic hydrolyzate without shortening hydraulic retention time

Bioplastics have garnered substantial interest as alternatives to conventional petroleum-based plastics. However, their management and conversion to biogas continues to be significantly challenging. In this study, we evaluated the suitability of various plastics for hydrolysis at 160 °C for 12 h using different solvents. The biogas yield (BGY) of the monomers constituting these plastics and the obtained plastic hydrolyzates was comprehensively evaluated. When water was used as a solvent, 100 % hydrolysis of polylactic acid (PLA) and polybutylene succinate (PBS) was observed. When polybutylene adipate co-terephthalate (PBAT) and polyhydroxybutyrate (PHB) were hydrolyzed with water, the degradation ratio was approximately 30 %; however, using an aqueous lactic acid solution as a solvent improved the degradation ratio to 78 % and 100 %, respectively. In the BGY test of the plastic hydrolyzates, the biogas volumes derived from the hydrolyzates were 563, 461, 337, and 573 mL/g COD-added for PLA, PBS, PBAT, and PHB, respectively. With 1,160 gCOD/L waste PLA hydrolyzate, continuous co-digestion of sewage sludge and the hydrolyzate was conducted. Organic loading rates of sewage sludge and the hydrolyzate were 2.3 and 2.4 gCOD/L/d, respectively. The operation was stable and the methane production volume from the PLA hydrolyzate was 414 L/kgCOD-added. Using highly concentrated PLA hydrolyzate, the hydraulic retention time was 19.3 days, which was only 0.7 days shorter than that of anaerobic digestion of sewage sludge only (20 days). Therefore, highly concentrated PLA hydrolyzate maintains the retention time of normal sewage sludge digestion. Conclusively, the present study has crucial practical implications for plastic waste management.

Bioactive materials‐coated polybutylene‐adipate‐co‐terephthalate 3D‐printed scaffolds for application in the bone tissues engineering

AbstractBone tissue engineering (BTE) is a biomedical area that develops scaffolds capable of mimicking and repairing damage on bone tissue. For this, a popular and nonexpensive 3D printing technique named fused deposition modeling (FDM) has been used. The potential use of 3D scaffolds of poly(butylene adipate‐co‐terephthalate (PBAT) has been investigated in BTE since this polymer presents good biocompatibility and degradability, as well as mechanical properties like those offered by the natural bone. A single material does not have the features to promote cell adhesion, proliferation, and differentiation; the incorporation of bioactive substances can overcome this issue. This work aimed to develop 3D printed PBAT scaffolds by FDM technique and coated them with hydroxyapatite (H), bioglass (B), and gelatin (G) by solution immersion technique to obtain a functional biomaterial to be applied on the BTE. Structural characteristics and morphological and mechanical properties of the 3D scaffolds were evaluated. The cell proliferation and mineralization of pre‐osteoblastic cells (MC3T3‐E1) were accessed by methylthiazolyldiphenyl‐tetrazolium bromide, sulphorodhamine B, and Alizarin red assay, respectively. 3D printed PBAT scaffolds were successfully obtained by FDM, and the surface modification of 3D PBAT was proven through the changes observed in structural and morphological characteristics. In addition, the mechanical properties were improved in the modified scaffolds. Also, the coated 3D PBAT scaffolds with any bioactive substance increased and promoted cell proliferation and pre‐osteoblastic differentiation. Therefore, the combination of 3D PBAT scaffolds and H, G, and/or B (doped with niobium) is an alternative to produce functional biomaterials for BTE.

Evaluating novel biodegradable polymer matrix fertilizers for nitrogen-efficient agriculture.

Enhanced efficiency fertilizers (EEFs) can reduce nitrogen (N) losses in temperate agriculture but are less effective in the tropics. We aimed to design a new EEF and evaluate their performance in simple-to-complex tests with tropical soils and crops. We melt-extruded urea at different loadings into biodegradable polymer matrix composites using biodegradable polyhydroxyalkanoate (PHA) or polybutylene adipate-co-terephthalate (PBAT) polymers with urea distributed throughout the pellet. These contrast with commercially coated EEF that have a polymer-coated urea core. We hypothesized that matrix fertilizers would have an intermediate N release rate compared to fast release from urea or slow release from coated EEF. Nitrogen release rates in water and sand-soil columns confirmed that the matrix fertilizer formulations had a more progressive N release than a coated EEF. A more complex picture emerged from testing sorghum [Sorghum bicolor (L.) Moench] grown to maturity in large soil pots, as the different formulations resulted in minor differences in plant N accumulation and grain production. This confirms the need to consider soil interactions, microbial processes, crop physiology, and phenology for evaluating fertilizer performance. Promisingly, crop δ15N signatures emerged as an integrated measure of efficacy, tracking likely N conversions and losses. The three complementary evaluations combine the advantages of standardized high-throughput screening and more resource-intensive and realistic testing in a plant-soil system. We conclude that melt-blended biodegradable polymer matrix fertilizers show promise as EEF because they can be designed toward more abiotically or more microbially driven N release by selecting biopolymer type and N loading rate.

The impact of arbuscular mycorrhizal fungi and endophytic bacteria on peanuts under the combined pollution of cadmium and microplastics

It remains unclear how symbiotic microbes impact the growth of peanuts when they are exposed to the pollutants cadmium (Cd) and microplastics (MPs) simultaneously. This study aimed to investigate the effects of endophytic bacteria Bacillus velezens SC60 and arbuscular mycorrhizal fungus Rhizophagus irregularis on peanut growth and rhizosphere microbial communities in the presence of Cd at 40 (Cd40) or 80 (Cd80) mg kg−1 combined without MP or the presence of low-density polyethylene (LDPE) and poly butyleneadipate-co-terephthalate (PBAT). This study assessed soil indicators, plant parameters, and Cd accumulation indicators. Results showed that the application of R. irregularis and B. velezens significantly enhanced soil organic carbon and increased Cd content under the conditions of Cd80 and MPs co-pollution. R. irregularis and B. velezens treatment increased peanut absorption and the enrichment coefficient for Cd, with predominate concentrations localized in the peanut roots, especially under combined pollution by Cd and MPs. Under treatments with Cd40 and Cd80 combined with PBAT pollution, soil microbes Proteobacteria exhibited a higher relative abundance, while Actinobacteria showed a higher relative abundance under treatments with Cd40 and Cd80 combined with LDPE pollution. In conclusion, under the combined pollution conditions of MPs and Cd, the co-treatment of R. irregularis and B. velezens effectively immobilized Cd in peanut roots, impeding its translocation to the shoot.

Testing the Biodegradability and Biodegradation Rate of Bio-based Film Products in Composting Environment

Bio-based film products have a considerable interest as a replacement for petroleum synthetic polymers of plastics. They are manufactured with a blend of corn starch such as Poly Lactic Acid (PLA) and Poly Butylene Adipate-co-Terephthalate (PBAT) based raw materials that have been specifically engineered to facilitate the process of biodegradation and compost ability. Hence, biodegradable polymers have been regarded as a promising solution to tackle the pollution caused by the wide use of conventional polymers. As the main responsible institute for integrating environmental considerations into the country‘s development process, the Central Environment Authority of Sri Lanka has taken an action to ban food wrappers (lunch sheets) made from conventional polymers in Sri Lanka. Thus, this study was to determine the biodegradability of bioplastic materials lunch sheets, available on the Sri Lankan market that are labeled as 100% biodegradable but not certified as compostable. The other specific objectives are to identify the biodegradability rate of each brand of lunch sheets, categorize those lunch sheets according to their biodegradability and finally get an idea to determine the optimum conditions for the biodegradation of a bio- based lunch sheet. In this study, the test was carried out in a controlled composting environment located in Gampaha–Dompe Green Park. Three different brands of biodegradable bio-based film products were tested together with cellulose paper as the positive control and nonbiodegradable lunch sheet (LDPE) as the negative control. The project length was 15 weeks. Samples were placed into frames which are made of wooden slats as width=280 mm, length=340 mm and height=50 mm and a 1x1 mm polyethylene mesh was fixed onto the frames. The methodology adopted was based on the study conducted in the Czech Republic in 2016. The emphasis was put on discovering whether bio-based film products are biodegradable or not. The biodegradability of each bio-based film product was tested using Visual inspection; the decomposed samples were inspected visually comparing with initial samples, Weight loss measurement; the initial weight and the weight after decomposition were measured using an analytical balance, FTIR and TGA analysis. Furthermore, the quality of the compost was analyzed using quality parameters such as pH, electrical conductivity, moisture, organic carbon%, nitrogen%, phosphorous%, potassium%, C/N ratio and S. The visual inspection of Sample C revealed large cracks and porous structure than Sample A and Sample B. Positive control was completely digested and the negative control stayed as it is. According to the weight loss measurement analysis, the positive control totally degraded and degradation order was Sample C&gt;Sample A&gt;Sample B. The TGA only suggested a partial degradation of samples. FTIR analysis indicated that the positive control was totally biodegradable, Sample B and sample C partially biodegradable and Sample A and negative control were not biodegradable. Based on the results it can be concluded that bio- based film products have not decomposed completely but their color, texture changed. Sample B exhibited the highest degradation rate and exhibited a high degree ofdecomposition. The degradation rate can be summarized as Positive control&gt;Sample B&gt;Sample C&gt;Sample A&gt; Negative Control respectively. The main conclusion from this study is that the biodegradation of bioplastics materials strongly depends on both the environment in which they are placed and the chemical nature of the material. &#x0D; Keywords: Biodegradation, Biobased film products, Composting environment

Effect of Starch Plasticization on Morphological, Mechanical, Crystalline, Thermal, and Optical Behavior of Poly(butylene adipate-co-terephthalate)/Thermoplastic Starch Composite Films.

Starches plasticized with glycerol/citric acid/stearic acid and tributyl 2-acetylcitrate (ATBC), respectively, were processed with poly (butylene adipate-Co-terephthalate (PBAT) via extrusion and a film-blown process. All the composite films were determined for morphology, mechanical, thermal stability, crystalline, and optical properties. Results show that the most improved morphology was in the 30% glycerol plasticized PBAT/thermoplastic starch (TPS) composite films, characterized by the smallest and narrowest distribution of TPS particle sizes and a more uniform dispersion of TPS particles. However, the water absorption of PBAT/TPS composite films plasticized with glycerol surpassed that observed with ATBC as a plasticizer. Mechanical properties indicated insufficient plasticization of the starch crystal structure when using 10% ATBC, 20% ATBC, and 20% glycerol as plasticizers, leading to poor compatibility between PBAT and TPS. This resulted in stress concentration points under external forces, adversely affecting the mechanical properties of the composites. All PBAT/TPS composite films exhibited a negative impact on the initial thermal decomposition temperature compared to PBAT. Additionally, the haze value of PBAT/TPS composite films exceeded 96%, while pure PBAT had a haze value of 47.42%. Films plasticized with 10% ATBC, 20% ATBC, and 20% glycerol displayed lower transmittance values in the visible light region. The increased transmittance of films plasticized with 30% glycerol further demonstrated their superior plasticizing effect compared to other PBAT/TPS composite films. This study provides a simple and feasible method for preparing low-cost PBAT composites, and their extensions are expected to further replace general-purpose plastics in daily applications.

Direct Pellet Three-Dimensional Printing of Polybutylene Adipate-co-Terephthalate for a Greener Future.

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 Effect of Electrospinning Parameters on the Electrospun Polybutylene Adipate Co-Terephthalate (PBAT) Biodegradable Scaffold

Electrospinning is a cost-effective and versatile technique to fabricate continuous fibers ranging from submicron diameter to nanometer diameter. Polybutylene adipate-co-terephthalate (PBAT) has been investigated as a fibrous scaffold because of its low crystallinity, rapid biodegradability, and excellent mechanical properties, particularly for its high toughness and flexibility. However, the potential of the PBAT fibrous scaffold for medical purposes is still limited. PBAT blends with biocompatible polymers have been developed and investigated for tissue engineering applications. Herein, the preliminary research examines the processability of neat PBAT as a fibrous scaffold by varying several electrospinning processing parameters, such as solution concentration, voltage, flow rate, and tip to collector distance. The aim is to obtain continuous, smooth, and bead-free fibers. The electrospun fibers were examined using a scanning electron microscope (SEM) to determine its diameters. The optimum parameters for obtaining a continuous, bead-free PBAT fibrous scaffold were 20% w/v concentration, 19 kV voltage, 2 mL/h flow rate, and a 15 cm distance.

Upcycling waste tempura flake-derived starch powder as an environment-friendly polymer matrix filler for thermoplastic starch compounds

Waste tempura flakes collected from local restaurants were upcycled to be utilized as a polymer filler material. The oil fraction in collected waste tempura flakes were extracted two times via centrifugal solid-liquid separation and organic solvent extraction. Then, oil-extracted residual starch was freeze-milled to produce fine powders. Waste tempura flake-derived starch powder was substituted with 1%, 3%, and 5% (wt%) of virgin starch powder to produce thermoplastic starch. Composition, X-ray diffraction, and Fourier transform infrared analyses showed that the mixture was successfully thermally plasticized. Substitution of waste tempura flake-derived starch decreased tensile strength while increasing elongation at break of some samples. Produced thermoplastic starch samples again were compounded with polylactic acid (PLA) and poly-butylene adipate-co-terephthalate (PBAT) following a mixing ratio of 3:5:2. The analyses indicated that thermoplastic starch, PLA, and PBAT were successfully compounded. The compound containing 1 wt% substituted thermoplastic starch showed the minimal mechanical strength decrease. This study revealed the possibility of upcycling waste fried food into a valuable bioplastic material. Waste tempura flakes can be utilized as both bio-jet fuel and bioplastic filler material.

Synthesis of ionic liquid modified 1‐D nanomaterial and its strategical distribution into the biodegradable binary polymer matrix to get reduced electrical percolation threshold and electromagnetic interference shielding effectiveness

AbstractIonic liquid is increasingly being used as a chemical modulator of multi‐walled carbon nanotubes (MWCNT). Here, we report the practical method for producing biodegradable electromagnetic interference (EMI) shield films made of thermoplastic polyurethane (TPU), polybutylene adipate‐co‐terephthalate (PBAT), and 1‐(2‐aminoethyl)‐3‐methyl‐1H‐imidazol‐3‐ium modified MWCNT (MIL). The field emission scanning electron microscopy study of cryo‐fractured 50:50 PBAT/TPU blend giving co‐continuous morphology and subsequent polymer EMI shield nanocomposite material had shown the co‐continuous nanofiller distribution. The nanoparticles were chosen to be distributed in the PBAT portion, according to subsequent research employing HRTEM and DMA. The electrical percolation threshold (EPT) is determined to be situated within 1–3 wt% of nanoparticles loading as the remarkable shift in total EMI shielding efficiency from −14.6 dB (for 1 wt%) to −28.6 dB (for 3 wt%) of nanoparticle‐loaded film at 10 GHz (in X‐band region) for a 0.8 mm thick film reveals that the EPT is approximately at 2 wt% of nanoparticle loading. The effective EMI shielding of −37.3 dB was achieved by 10 wt% of MIL loading.

Biochar from Digestate Pyrolysis as a Filler for Biopolymer Blends: Effect of Blend Composition

Abstract This study investigates the effect of biochar (BC) as a filler for biopolymer blends, with a focus on the effect of the biopolymer weight ratio on the final BC-added blends. The blends studied in this work were obtained by varying the weight ratio of poly-butylene adipate-co-terephthalate (PBAT) and polylactic acid (PLA) due to their great importance in packaging and agricultural fields. BC has been produced in our laboratories by the slow pyrolysis of the digestate obtained from the anaerobic digestion of the organic fraction of municipal solid waste (OFMSW). After pyrolysis, digestate-derived biochar has been milled and sieved to produce a powdery form with diameter of less than 45 μm. In order to better investigate the filler/polymer interactions, biochar particles were dimensionally, morphologically and chemically characterised. The inhomogeneity of the feedstock is responsible for content and high diversity of inorganics in biochar surface. The effect of BC on PBAT and PLA biopolymer matrices is different, and for the blend compositions the relative weight ratio between PBAT and PLA plays an important role. Furthermore, the biocomposite blend has been fully characterised: rheological, morphological, mechanical and dynamic-mechanical characterisations have been carried out, highlighting how the properties results strongly influenced by the presence of BC in the blend. In addition, a study of the viscous molar mass of the two polymer matrices when processed in the presence or absence of BC particless highlighting that a strong chemical interaction occurs between PLA and BC particles, unlike PBAT and BC. Graphical Abstract

Scale-up fabrication of a biodegradable PBAT/PLA composite film compatibilized with a chain extender for industrial agricultural mulch film application

Low-density polyethylene (LDPE) mulch films have become a prevalent practice in agriculture to increase crop yield. However, because of their high environmental impact after use, biodegradable plastic films are considered desirable alternatives in agroecosystems. Herein, a polybutylene adipate-co-terephthalate (PBAT) and polylactic acid (PLA) composite film compatibilized with a chain extender (CE) was prepared via a two-step extrusion process. First, PBAT and PLA were blended at different ratios in a laboratory-scale twin-screw extruder, and the PBAT/PLA blends (80/20 wt.%) compatibilized with 1 phr of CE exhibited the most comparable physicochemical properties. The CE integration into the PBAT/PLA binary blend significantly increased mechanical rigidity and strength (p ≤ 0.05). The enhanced compatibility between the immiscible polymers was verified through thermal and phase morphological analyses. The optimum composite was then produced using a pilot-scale extrusion system. The pilot-scale extruded optimal biodegradable mulch composite exhibited excellent water barrier properties, as evidenced by a water vapor permeability of 0.83 g mm/m2·day·kPa and a water contact angle of 93.77° These values surpassed those of commercially available biodegradable mulch films. Furthermore, it demonstrated a weight reduction of 2.9% during a 3-month period of soil burial, exhibiting durability compared to commercial biodegradable mulch films. These results suggest that the developed film has great potential for practical food and agricultural applications.