Poly Butylene Adipate Co-terephthalate Research Articles

Enhancing biodegradation of PBAT through bio-stimulation using Pseudozyma jejuensis for effective plastic waste reduction

Polybutylene adipate-co-terephthalate (PBAT) is a flexible and biodegradable material that finds applications in mulching film and the food packaging industry. In this study, we aimed to address the global plastic waste problem by developing an improved biodegradation system for PBAT. Our focus was on utilizing the biodegradation capabilities of Pseudozyma jejuensis, a microorganism known for its ability to decompose Polycaprolactam (PCL). Through bio-stimulation, we aimed to enhance the growth mechanism of P. jejuensis and optimize PBAT biodegradation. Our results demonstrated significant structural changes in the PBAT film, as revealed by FT-IR analysis. Moreover, FE-SEM imaging exhibited evident surface erosion and pitting, indicating physical alterations due to biodegradation. These findings provide strong evidence for the efficiency of our developed biodegradation system. To fully harness the potential of this system and enable its practical implementation, further research is warranted to optimize and scale up the process. Our work contributes to the ongoing efforts to combat the global plastic waste crisis, offering a valuable solution for the efficient biodegradation of PBAT.

Effect of Plasticizer and Compatibilizer on Properties of Polybutylene Adipate-Co-Terephthalate (PBAT) with Acetylated Starch

Effect of Plasticizer and Compatibilizer on Properties of Polybutylene Adipate-Co-Terephthalate (PBAT) with Acetylated Starch

Assessing labelled carbon assimilation from poly butylene adipate-co-terephthalate (PBAT) monomers during thermophilic anaerobic digestion

PBAT (poly butylene adipate-co-terephthalate) is a widely used biodegradable plastic, but the knowledge about its metabolization in anaerobic environments is very limited. In this study, the anaerobic digester sludge from a municipal wastewater treatment plant was used as inoculum to investigate the biodegradability of PBAT monomers in thermophilic conditions. The research employs a combination of 13C-labelled monomers and proteogenomics to track the labelled carbon and identify the microorganisms involved. A total of 122 labelled peptides of interest were identified for adipic acid (AA) and 1,4-butanedio (BD). Through the time-dependent isotopic enrichment and isotopic profile distributions, Bacteroides, Ichthyobacterium, and Methanosarcina were proven to be directly involved in the metabolization of at least one monomer. This study provides a first insight into the identity and genomic potential of microorganisms responsible for biodegradability of PBAT monomers during anaerobic digestion under thermophilic conditions.

Dynamics of macroplastics and microplastics formed by biodegradable mulch film in an agricultural field

Conventional plastic mulch brings agronomic and economic benefits to crop production, but a large amount of plastic waste amasses when the mulch is removed from the fields after harvest. Soil-biodegradable plastic mulch (BDM) has emerged as a promising alternative to conventional plastic mulch as it can be tilled into the soil after harvest, thereby alleviating disposal problems. However, direct evidence on complete degradation of biodegradable mulch under natural conditions is still lacking. We quantified the dynamics of macro- (>5 mm) and microplastics (0.1–5 mm in size) in four years after a one-time application of mulch in a field with monoculture maize. The BDM feedstock was polybutyleneadipate-co-terephthalate (PBAT) and polylactic acid (PLA)-based, and both a clear and black BDM were tested. The BDM plastic mulch films degraded into macro- and micoplastics. Macroplastics disappeared 2.5 years after mulch incorporation. We developed a new extraction method for biodegradable microplastics using a sequential density fractionation approach with a H2O and a ZnCl2 solution. Microplastic concentrations in the soil ranged from 350 to 525 particles/kg after 2.5 years, 175 to 250 particles/kg after 3 years, and 50 to 125 particles/kg after 3.5 year following mulch incorporation. This continuous decrease of detectable plastic particle concentrations in soil suggests that BDMs fragment degrade into smaller and smaller particles, which eventually may biodegrade completely. While we cannot ascertain whether persistent and undetectable nanoplastics may form, macro- and microplastics formed from BDM seem to disappear with time.

Preparation of ultrafine wheat straws with co-milling and its incorporation for biodegradable mulch film production with enhanced performance

Although polybutylene adipate-co-terephthalate (PBAT)-based biodegradable mulch films are potential in replacing the traditional polyethene ones with increased cultivation sustainability, some practical issues including the high price and low performance still need to be resolved. Here, ultrafine powder of zero-cost straws was doped into PBAT-based films due to its toughness and ultraviolet (UV)-resistance. The powder was prepared by co-milling with a few calcium carbonates, which act as not only a friction agent to greatly increase the milling efficiency, but also an anti-blocking agent during film blowing. Slight changes in rheological and thermal behaviors of the composite films were observed with the introduction of this ultrafine filler, thus have no crucial effect on film processing. However, the UV-blocking and aging-resistant properties of the films were both enhanced, which is quite essential to a mulch film for long-term cultivation. Meanwhile, the mechanical and the water vapor barrier properties were also slightly increased with the addition of < 10 wt% fillers. It is noted that the films can meet the standards of biodegradable mulch films even after 80.9-h UV irradiation. Besides, the cost is estimated to reduce over 8.14%, which makes it quite feasible for mulching in the future.

Biodegradable Electrohydraulic Soft Actuators

Biodegradable materials decompose and return to nature. This functionality can be applied to derive robotic systems that are environmentally friendly. This study presents a fully biodegradable soft actuator, which is one of the key elements in “green” soft robotics. The working of the actuator is based on an electrohydraulic principle, which is similar to that of hydraulically amplified self‐healing electrostatic actuators. The actuator developed in this study consists of a dielectric film made of polylactic acid (PLA) and polybutylene adipate‐co‐terephthalate (PBAT), with soybean oil as the dielectric liquid and electrodes made from a mixture of gelatin, glycerol, and sodium chloride (NaCl). The synthesized biodegradable electrode material exhibits a Young's modulus of 0.06 MPa and resistivity of 258 Ω·m when the mass fraction of NaCl relative to the amount of gelatin and glycerol is 10 wt%. The softness and resistivity of the electrode material results in actuation strain values of 3.2% (at 1 kV, corresponding to 1.2 kV mm−1) and 18.6% (at 10 kV, corresponding to 9.6 kV mm−1) for the linear‐type and circular‐type actuators, respectively. These values obtained for the biodegradable electrohydraulic soft actuators are comparable to those of nonbiodegradable actuators of the same type, representing the successful implementation of the concept.

Tannic acid as a crosslinking agent in poly(butylene adipate-co-terephthalate) composite films enhanced with carbon nanoparticles: Processing, characterization, and antimicrobial activities for food packaging

The disposal of plastics waste is currently a major environmental problem. Plastics are used frequently and in more variety in everyday life, which has an effect on the environment. As a result of the emissions of carbon dioxide caused by burning of non-biodegradable polymers like polyethylene, polypropylene, and polyvinyl chloride, there is a growing concern of a global warming. This article discusses the carbonization and activation of KOH to produce porous carbon nanoparticles (CNPs). The solution casting method was used to produced composites of poly(butylene adipate-co-terephthalate (PBAT) with CNPs and tannic acid (TA). PBAT composites employing CNPs as reinforcement and TA as a cross-linker. TA and CNPs have been taken into account in investigating the morphological and antimicrobial activities of PBAT-based composites. The mechanical strength of PBAT/TA/CNPs composites increased as a result to the strengthening characteristics of CNPs. The thermal characterization of PBAT/TA/CNPs composites was improved with TA and CNPs, based on thermogravimetric analysis (TGA). Contact angle measurements show that after reinforcement, PBAT/TA/CNPs composites became hydrophobic. In PBAT/TA/CNPs composites, the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) are reduced. The PBAT/TA/CNPs composites showed greater antimicrobial activity against the food-borne pathogenic microorganisms E. coli and S. aureus. Also, the results of food quality tests that PBAT/TA/CNPs composites used to have an improved shelf life for sliced carrot than control, commercial and PBAT film extending it from 1 to 12 days. The results indicated that PBAT/TA/CNPs composites would be suitable choices for materials to be used in food packaging.

Aging of biodegradable-mulch-derived microplastics reduces their sorption capacity of atrazine

Degradable plastics are gradually regarded as alternatives of conventional, synthetic organic polymers to reduce the plastics or microplastics (MPs) pollution; however, the reports upon environmental risk of degradable plastics are still limited. In order to evaluate the potential vector effect of biodegradable MPs on coexisting contaminants, sorption of atrazine onto pristine and ultraviolet-aged (UV) polybutylene adipate co-terephthalate (PBAT) MPs and polybutylene succinate co-terephthalate (PBST) MPs were investigated. The results showed that, UV aging led to more wrinkles and cracks on the surface, increased homogeneous chains proportion, enhanced hydrophobicity, and enlarged crystallinity of both MPs. The sorption kinetics of atrazine to MPs fitted well into pseudo-first-order (R2 = 0.809–0.996) and pseudo-second-order (R2 = 0.889–0.994) models. In the concentration range of 0.5–25 mg L−1, the sorption isotherm fitted into linear (R2 = 0.967–0.996) and Freundlich model (R2 = 0.972–0.997), indicating that the absorption partitioning was the dominant sorption mechanism. The partition coefficient (Kd) of atrazine to PBAT- MPs (40.11–66.01 L kg−1) was higher than that of PBST- MPs (34.34–57.96 L kg−1), and the Kd values of both MPs declined for aged MPs. The specific surface area, hydrophobicity, polarity and crystallinity of MPs jointly interpreted the changing sorption capacity of the MPs. In the present study, both aged PBAT- and aged PBST- MPs exhibited lower vector potential to atrazine than pristine MPs, suggesting reduced risk of being a pollutant carrier, which is of great significance for the development of biodegradable plastics.

Feasibility Study on the Application of Biodegradable Plastic Film in Farmland Soil in Southern Xinjiang, China-Planting Tomatoes as an Example.

In recent years, polybutylene adipate-co-terephthalate (PBAT) mulch film has become one of the most commonly used biodegradable mulch films in agriculture in an attempt to combat plastic film pollution. However, its degradation characteristics and impact on the soil environment and crop growth are affected by many factors such as its composition, soil and crop types, local climate characteristics, etc. In this study, PBAT mulch film and ordinary polyethylene (PE) film were used as test materials, with non-mulching treatment (CK) as a control, to study the applicability of PBAT film in Moyu County, Southern Xinjiang region, using tomato growth as an example. The results showed that PBAT film started its induction period after 60 days, and 60.98% of the PBAT film was degraded within 100 days. Generally, the soil temperature and humidity preservation functions of this film were comparable to that of PE film in the seedling and flowering-fruiting stages of tomato growth. In the mature stage, the soil humidity under PBAT film was significantly lower than that of PE film due to its substantial degradation rate. However, this did not have any significant negative effects on tomato growth, yield, and quality. The tomato yield of 667 m2 with BPAT was insignificantly lower than that of PE film by 3.14%, and both were significantly higher than that of the CK treatment by 63.38% and 68.68%, respectively, indicating that it is feasible to use PBAT film to cultivate crops such as tomato in the arid region of Southern Xinjiang, China.

Effect of Crystallization Temperature on the Mechanical and Physical Properties of Solution Cast Polybutylene adipate co-terephthalate/Thermoplastic Starch Films

Starch-based biodegradable films of polybutylene adipate co-terephthalate (PBAT) have been prepared by the solution casting method. The effect of heating at two different temperatures (80 and 110°C) on the mechanical, optical and morphological properties of these films has been evaluated. The two temperatures were selected based on the crystallization and melting temperatures of PBAT. The blend of PBAT with thermoplastic starch has been prepared by melt mixing technique using two roll mills and then the solution casting method has been followed to prepare the films. Apart from curing at room temperature, the films have been cured at 80°C and 110°C. The tensile strength of the films increased by 110% and 252% for films heated to 80°C and 110°C, respectively. As revealed from spectroscopic analysis, the heating of films has no significant effect on the absorption of light by the films in the UV-visible region. The bonding characteristics of the films have been evaluated using Fourier transform infrared (FTIR) spectroscopy. The lowest water absorption and vapour permeability have been obtained in films cured at 80°C.

Discovery of plastic-degrading microbial strains isolated from the alpine and Arctic terrestrial plastisphere.

Increasing plastic production and the release of some plastic in to the environment highlight the need for circular plastic economy. Microorganisms have a great potential to enable a more sustainable plastic economy by biodegradation and enzymatic recycling of polymers. Temperature is a crucial parameter affecting biodegradation rates, but so far microbial plastic degradation has mostly been studied at temperatures above 20°C. Here, we isolated 34 cold-adapted microbial strains from the plastisphere using plastics buried in alpine and Arctic soils during laboratory incubations as well as plastics collected directly from Arctic terrestrial environments. We tested their ability to degrade, at 15°C, conventional polyethylene (PE) and the biodegradable plastics polyester-polyurethane (PUR; Impranil®); ecovio® and BI-OPL, two commercial plastic films made of polybutylene adipate-co-terephthalate (PBAT) and polylactic acid (PLA); pure PBAT; and pure PLA. Agar clearing tests indicated that 19 strains had the ability to degrade the dispersed PUR. Weight-loss analysis showed degradation of the polyester plastic films ecovio® and BI-OPL by 12 and 5 strains, respectively, whereas no strain was able to break down PE. NMR analysis revealed significant mass reduction of the PBAT and PLA components in the biodegradable plastic films by 8 and 7 strains, respectively. Co-hydrolysis experiments with a polymer-embedded fluorogenic probe revealed the potential of many strains to depolymerize PBAT. Neodevriesia and Lachnellula strains were able to degrade all the tested biodegradable plastic materials, making these strains especially promising for future applications. Further, the composition of the culturing medium strongly affected the microbial plastic degradation, with different strains having different optimal conditions. In our study we discovered many novel microbial taxa with the ability to break down biodegradable plastic films, dispersed PUR, and PBAT, providing a strong foundation to underline the role of biodegradable polymers in a circular plastic economy.

Aggregation kinetics and stability of biodegradable nanoplastics in aquatic environments: Effects of UV-weathering and proteins

Plastic pollution caused by conventional plastics has promoted the development and use of biodegradable plastics. However, biodegradable plastics do not degrade readily in water; instead, they can generate micro- and nanoplastics. Compared to microplastics, nanoplastics are more likely to cause negative impacts to the aquatic environment due to their smaller size. The impacts of biodegradable nanoplastics highly depend on their aggregation behavior and colloidal stability, which still remain unknown. Here, we studied the aggregation kinetics of biodegradable nanoplastics made of polybutylene adipate co-terephthalate (PBAT) in NaCl and CaCl2 solutions as well as in natural waters before and after weathering. We further studied the effect of proteins on aggregation kinetics with both negative-charged bovine serum albumin (BSA) and positive-charged lysozyme (LSZ). For pristine PBAT nanoplastics (before weathering), Ca2＋ destabilized nanoplastic suspensions more aggressively than Na+, with the critical coagulation concentration being 20 mM in CaCl2 vs 325 mM in NaCl. Both BSA and LSZ promoted the aggregation of pristine PBAT nanoplastics, and LSZ showed a more pronounced effect. However, no aggregation was observed for weathered PBAT nanoplastics under most experimental conditions. Further stability tests demonstrated that pristine PBAT nanoplastics aggregated substantially in seawater, but not in freshwater, and only slightly in soil pore water; while weathered PBAT nanoplastics remained stable in all natural waters. These results suggest that biodegradable nanoplastics, especially weathered biodegradable nanoplastics, are highly stable in the aquatic environment, even in the marine environment.

Integration of ARTP Mutation and Adaptive Laboratory Evolution to Reveal 1,4-Butanediol Degradation in Pseudomonas putida KT2440.

Biotransformation of plastics or their depolymerization monomers as raw materials would offer a better end-of-life solutions to the plastic waste dilemma. 1,4-butanediol (BDO) is one of the major depolymerization monomers of many plastics polymers. BDO valorization presents great significance for waste plastic up-recycling and fermenting feedstock exploitation. In the present study, atmospheric pressure room temperature plasma (ARTP)-induced mutation combined with adaptive laboratory evolution (ALE) was used to improve the BDO utilization capability of Pseudomonas putida KT2440. The excellent mutant P. putida NB10 was isolated and stored in the China Typical Culture Preservation Center (CCTCC) with the deposit number M 2021482. Whole-genome resequencing and transcriptome analysis revealed that the BDO degradation process consists of β-oxidation, glyoxylate carboligase (GCL) pathway, glyoxylate cycle and gluconeogenesis pathway. The imbalance between the two key intermediates (acetyl-CoA and glycolyl-CoA) and the accumulation of cytotoxic aldehydes resulted in the weak metabolism performance of KT2440 in the utilization of BDO. The balance of the carbon flux and enhanced tolerance to cytotoxic intermediates endow NB10 with great BDO degradation capability. This study deeply revealed the metabolic mechanism behind BDO degradation and provided an excellent chassis cell for BDO further up-cycling to high-value chemicals. IMPORTANCE Plastic waste represents not only a global pollution problem but also a carbon-rich, low-cost, globally renewable feedstock for industrial biotechnology. BDO is the basic material for polybutylene terephthalate (PBT), poly butylene adipate-co-terephthalate (PBAT), poly (butylene succinate) (PBS), etc. Herein, the construction of BDO valorization cell factory presents great significance for waste plastic up-recycling and novel fermentation feedstock exploitation. However, BDO is hard to be metabolized and its metabolic pathway is unclear. This study presents a P. putida mutant NB10, obtained through the integration of ARTP and ALE, displaying significant growth improvement with BDO as the sole carbon source. Further genome resequencing, transcriptome analysis and genetic engineering deeply revealed the metabolic mechanism behind BDO degradation in P. putida, this study offers an excellent microbial chassis and modification strategy for plastic waste up-cycling.

Enhanced compatibility and functionality of thermoplastic cassava starch blended PBAT blown films with erythorbate and nitrite

Improved miscibility between thermoplastic starch (TPS) and polybutylene adipate-co-terephthalate (PBAT) enhances processability and properties of TPS-based biodegradable plastic packaging. This research investigated compatibility and functionality of TPS/PBAT (50/50) blends with sodium nitrite and sodium erythorbate (1–5%) via blown film extrusion. Film morphology and mechanical and barrier properties were investigated. Sodium nitrite and sodium erythorbate improved processing efficiency of TPS, modified film flexibility and enhanced physical and chemical compatibility between TPS and PBAT matrices via hydrolysis, confirmed by 1H NMR and ATR-FTIR analyses. These chemical reactions also affected thermal and phase transition behaviors. Increased starch granule dispersion caused smoother microstructure, resulting in higher oxygen barrier. Sodium nitrite and sodium erythorbate functionalized TPS/PBAT films reduced discoloration of packaged cured meat during storage at 4 °C for 9 days. These compounds provided extra functionality and improved compatibility between TPS and PBAT biodegradable plastic blends for novel and sustainable food packaging.

Long-term immersion of compostable plastics in marine aquarium: Microbial biofilm evolution and polymer degradation

The best-selling compostable plastics, polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT), can accidentally end up in the marine environment due to plastic waste mismanagement. Their degradation and colonization by microbial communities are poorly documented in marine conditions. To better understand their degradation, as well as the dynamics of bacterial colonization after a long immersion time (99, 160, and 260 days), PBAT, semicrystalline, and amorphous PLA films were immersed in a marine aquarium. Sequencing and chemical analyses were used in parallel to characterize these samples. Despite the variation in the chemical intrinsic parameters of these plastics, their degradation remains very slow. Microbial community structure varied according to the immersion time with a high proportion of Archaea. Moreover, the plastisphere structure of PBAT was specific. A better understanding of compostable plastic degradability is crucial to evaluate their impact on ecosystems and to eco-design new recyclable plastics with optimal degradation properties.

Identification of biodegradable plastics using differential scanning calorimetry and carbon composition with chemometrics

Biodegradable plastics have become an important commodity to replace non-degradable plastics and alleviate environment pollution. It is important to identify instances of counterfeit and mislabeled biodegradable plastics in the marketplace to avoid sustainability fraud and improve plastics waste recycling. In this study, differential scanning calorimetry (DSC) and elemental analyzer-isotope ratio mass spectrometry (EA-IRMS) were used to analyze biodegradable plastics (polylactic acid (PLA), poly butylene adipate-co-terephthalate (PBAT), PBAT/PLA blend (PBAT+PLA)) and non-degradable plastics (polyethylene terephthalate (PET), high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP)). A verification model was built using orthogonal partial least squares-discriminant analysis (OPLS-DA). Results showed that the melting point of biodegradable and non-degradable plastics ranged from 120 °C to 176 °C and 105 °C to 253 °C, respectively. The melting points of biodegradable PLA and non-degradable PP overlapped. The δ13C values of biodegradable and non-degradable plastics ranged from -25.8 ‰ to -11.6 ‰ and -32.3 ‰ to -25.4 ‰, respectively. The % C of biodegradable and non-degradable plastics ranged from 36.0% to 61.0% and 56.4% to 85.3%, respectively. Three OPLS-DA models were established by combining DSC variables, δ13C values and % C. The PLA discriminant accuracy of these models was 100%, suggesting this approach holds promise for the regulation and identification of biodegradable plastics in the marketplace.

Accelerated degradation of plastic products via yeast enzyme treatment

Biodegradable plastics can solve the problem of unwanted plastics accumulating in the environment if they can be given the contradictory properties of durability in use and rapid degradation after use. Commercially available agricultural biodegradable mulch films are made from formulations containing polybutylene adipate-co-terephthalate (PBAT) to provide mechanical and UV resistance during the growing season. Although used films are ploughed into the soil using a tiller to promote decomposition, it is difficult if they remain durable. We showed that an enzyme produced by the leaf surface yeast Pseudozyma antarctica (PaE) degrades PBAT-containing films. In laboratory studies, PaE randomly cleaved the PBAT polymer chain and induced erosion of the film surface. In the field, commercial biodegradable films containing PBAT placed on ridges were weakened in both the warm and cold seasons by spraying the culture filtrate of P. antarctica. After the field was ploughed the next day, the size and total weight of residual film fragments decreased significantly (p < 0.05). Durable biodegradable plastics used in the field are degraded using PaE treatment and are broken down into small fragments by the plough. The resultant degradation products can then be more readily assimilated by many soil microorganisms.

Development of natural fiber reinforced thermoplastic bonded hybrid wood veneer composite

This study aimed at preparing thermoplastic based hybrid wood veneer composite panels in which bamboo fiber reinforced thermoplastic (BPC) was used in granular form as one component and Melia dubia wood veneers as the second component. BPC was prepared using twin screw extruder and maleated polyethylene/ maleated polypropylene as a coupling agent. The effect of polymer type i.e., polypropylene (PP), high density polyethylene (HDPE) and poly butylene adipate-co-terephthalate (PBAT) and bamboo fiber content (10%, 30%, and 50%) on physical, mechanical and thermal properties of Melia dubia plywood has been investigated. Plywood prepared with BPC exhibited superior mechanical properties as compared to pure polymer irrespective of polymer type. The improvement in flexural strength at 30% bamboo content was 14.6%, 17.6% and 38% for PP, HDPE and PBAT based BPC, respectively. Volumetric swelling in panels on water absorption was not influenced by the presence of bamboo fibers in the polymer. The improvement in mechanical properties of BPC bonded plywood was due to manifestation of an improved interfacial adhesion between BPC and wood veneers via coupling agent. SEM images revealed pertinent bonding between BPC and wood veneers in the form of mechanical interlocking.

Improvement of Electrical and Mechanical Properties of PLA/PBAT Composites Using Coconut Shell Biochar for Antistatic Applications

Biochar-based environment-friendly polymer composites are suitable substitutes for conventional non-biodegradable polymer composites. In this work, we developed polylactic acid (PLA)/polybutylene adipate-co-terephthalate (PBAT)/biochar (BC) composites with improved mechanical and electrical properties for antistatic applications. Coconut shell biochar was obtained through the pyrolysis of coconut shell in an inert atmosphere, and characterised using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), to investigate the morphology and structural properties. The biochar was converted to powder form, sieved to reduce the particle size (≤30 μm diameters), and melt-mixed with PLA and PBAT to form composites. The composites were extruded to produce 3D printing filaments and, eventually, 3D-printed tensile specimens. The tensile strength and tensile modulus of the 3D-printed PLA/PBAT/BC (79/20/1) composite with 1 wt% of biochar improved by 45% and 18%, respectively, compared to those of PLA/PBAT (80/20). The interfacial interaction between the biochar and polymer matrix was strong, and the biochar particles improved the compatibility of the PLA and PBAT in the composites, improving the tensile strength. Additionally, the electrical resistivity of the composite did reduce with the addition of biochar, and PLA/PBAT/BC (70/20/10) showed the surface resistivity of ~1011 Ω/sq, making it a suitable material for antistatic applications.

Isolation and Degradation Characteristics of PBAT Film Degrading Bacteria.

In recent years, PBAT (polybutylene adipate-co-terephthalate) mulch has become one of the most commonly used biodegradable mulching films. In this paper, five potential strains of PBAT film degrading bacteria were screened from the soil sample using PBAT film as the sole carbon source. A highly efficient PBAT degrading strain JZ1 was isolated by comparing the degradation performance of PBAT mulching film identified as Peribacillus frigoritolerans S2313 by 16S rDNA sequence analysis. The capacity of the strain to degrade PBAT film was optimized by adjusting the cultivation conditions such as nitrogen source, pH, and inoculum volume. After 8 weeks of cultivation, the actual degradation rate of the strain to PBAT mulch film reached 12.45%. SEM (scanning electron microscopy) coupled with EDX (energy dispersive spectroscopy) analysis showed that microbial degradation is an oxidation process and is mainly due to the amorphous regions of the PBAT film. The biodegradation of PBAT film by Peribacillus frigoritolerans may provide a promising method for regulating the degradation progress of PBAT film in the farmlands.