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Lignin has many potential applications and is a biopolymer with a three-dimensional network structure. It is composed of three phenylpropane units, p-hydroxyphenyl, guaiacyl, and syringyl, connected by ether bonds and carbon–carbon bonds, and it contains a large number of phenol or aldehyde structural units, resulting in complex lignin structures. This limits the application of lignin. To expand the application range of lignin, we prepared lignin thermoplastic phenolic resins (LPRs) by using lignin instead of phenol; these LPRs had molecular weights of up to 1917 g/mol, a molecular weight distribution of 1.451, and an O/P value of up to 2.73. Due to the complex structure of the lignin, the synthetic lignin thermoplastic phenolic resins were not very tough, which greatly affected the performance of the material. If the lignin phenolic resins were toughened, their application range would be substantially expanded. Polybutylene succinate (PBS) has excellent processability and excellent mechanical properties. The toughening effects of different PBS contents in the LPRs were investigated. PBS was found to be compatible with the LPRs, and the flexible chain segments of the small PBS molecules were embedded in the molecular chain segments of the LPRs, thus reducing the crystallinities of the LPRs. The good compatibility between the two materials promoted hydrogen bond formation between the PBS and LPRs. Rheological data showed good interfacial bonding between the materials, and the modulus of the high-melting PBS made the LPRs more damage resistant. When PBS was added at 30%, the tensile strength of the LPRs was increased by 2.8 times to 1.65 MPa, and the elongation at break increased by 31 times to 93%. This work demonstrates the potential of lignin thermoplastic phenolic resins for industrial applications and provides novel concepts for toughening biobased aromatic resins with PBS.

To improve the performance of biodegradable materials and endow them with antimicrobial properties, herein, pyridine-3,5-dicarboxylic acid was introduced as a third monomer into the molecular chain of polybutylene succinate (PBS) via copolymerization, followed by introduction of pyridine quaternary ammonium into the PBS branched chain through nucleophilic substitution to afford antimicrobial PBS-BD, which was then comingled with polylactic acid (PLA) to prepare PBS-BD/PLA composites. X-ray diffraction analysis revealed that the introduction of pyridine-3,5-dicarboxylic acid caused a small shift in the diffraction peaks of PBS and a decrease in crystallinity, which was further decreased upon blending with PLA. PBS-BD and PLA were bound together by intermolecular forces. When the PBS-BD/PLA ratio was 8:2, the melting points of the two phases were the closest, the compatibility was the best, and the thermal and antimicrobial properties were optimal. The antimicrobial properties of the composites were gradually enhanced with increasing PBS-BD content, reaching optimal values for application as antimicrobial materials. The composites were degraded in soil supernatant for 6 months at a rate of 31.52%. After 42 d of enzymatic degradation, the degradation rate reached 23.24%. The PBS-BD/PLA composites promoted the growth of green vegetables to a certain extent and enhanced their nutritional value, reaching the highest chlorophyll content and vitamin C content after 45 d of growth in the presence of the composites.

Little is known about how the strength of biodegradable polymers changes during decomposition. This study investigated the changes in the tensile properties of polybutylene succinate (PBS) and basalt-fiber (BF)-reinforced PBS (PBS-BF) composite sheets during degradation in bacterial solutions. Seven days after the start of the experiment, the elongation at break of the PBS specimens decreased significantly, and the PBS-BF composite specimens were characterized by barely any change in ultimate tensile strength (UTS) after immersion in the bacteria-free medium for 7 and 56 days. Meanwhile, when immersed in the bacterial solution, the UTS of the PBS-BF composite specimens showed a tendency to decrease after 7 days. After 56 days, the UTS decreased to about half of its value immediately after fabrication. The degradation of the material was attributed to infiltration of the bacterial solution into structurally weak areas, causing decomposition throughout the material.

To improve the performance of biodegradable materials and endow them with functionality, luteolin (Lc) was modified by esterification with acetyl chloride (Ac), iso butyryl chloride (Ic), benzoyl chloride (Bc) to improve its hydrophilicity and hydrophobicity, and Ac-L, Ic-L and Bc-L esters were obtained. The three esterified compounds were characterized and blended with PBS to prepare PBS/Ac-L, PBS/Ic-L and PBS/Bc-L composites. Studied the interface interaction mechanism, crystallization performance, thermodynamic performance, hydrophilic properties, and antibacterial performance between composite materials. The results showed that the majority of Ac-L, Ic-L, and Bc-L were dispersed in the PBS matrix, with a tighter two-phase interface and higher dispersibility. There were electrostatic adsorption, hydrogen bond and other interactions in the composite system, and the Intermolecular force became stronger and the compatibility increased. The introduction of Ac-L, Ic-L, and Bc-L did not change the crystal structure of PBS, but the crystallization rate and crystallinity of the composite material increased. The thermal decomposition temperature of composite materials increased, and the thermal stability and mechanical properties were further enhanced. With the increase of the amount of Ac-L, Ic-L, and Bc-L added, the antibacterial and hydrophobic properties gradually enhanced, making it suitable for use as a preservation and antibacterial material.

Composite laminate recycling and waste disposal routes remain a burden to existing systems, requiring special treatment and separation. The inclusion of a plastic layer is important for several key properties that are required for food safety, which in turn has made these products exceptionally hard to substitute in food packaging. Yet, the continued use of non-degradable commodity plastics is unsustainable. In this research, we compare the four most promising biodegradable and bio-based plastics that could replace non-degradable plastics in laminates. Polyhydroxyalkanoate (PHA), polylactic acid (PLA), polybutylene succinate (PBS), and polybutylene succinate adipate (PBSA) were applied as a direct melt coating on porous cast hemp papers, and the final composite was compressed under three different loads: 0.5 MT, 1.5 MT, and 3.0 MT. To promote sustainable agriculture waste management, we opted to use cast paper made from ground hemp stalks. The formation of the composite structure was examined with scanning electron microscopy (SEM), while surface wetting on the paper side of the laminate was performed to understand structural changes induced by polymer impregnation into the paper layer. Mechanical performance properties were investigated with tensile and peel tests, and suitability for an extended range of temperatures was examined with dynamical mechanical analysis. An increase in compression pressure yielded up to a two-fold improvement in elastic modulus and tensile strength, while thermomechanical analysis revealed that the polymer’s transition into a viscoelastic state significantly affected the laminate’s storage modulus values. Biodegradation was performed in a controlled compost at 58 °C, resulting in full degradation within 40 to 80 days, with PLA and PHA laminates showing 40 and 50 days, respectively. Produced bioplastic laminates have a tremendous potential to replace polyolefin laminates in packaging applications.

A polybutylene succinate (PBS) composite reinforced with natural jute (Corchorus olitorius) fibers (50-80 μm) was investigated for its mechanical properties and biodegradability. This study aims to investigate the effects of fiber additions and size variations on composite performance and environmental sustainability. The PBS80/JF20 composite with 80 μm jute particles demonstrated the lowest MFI at 26 g.10 min-1, significantly lower than that of pure PBS (p<0.05), indicating reduced flowability. Tensile strength decreased with the addition of jute fiber, reaching 21.4 MPa with 50 μm particles. Density was also reduced, with the lowest recorded at 1.27 g.cm³- in PBS95/Jute5 (p<0.05). The composites with 80 μm fibers exhibited a slightly higher weight loss (9.5%) compared to those with 50 μm fibers (6.8%), likely due to insufficient interfacial adhesion in larger fibers, making them more susceptible to microbial degradation. Results indicate that adding natural jute fibers into the PBS matrix leads to significant decreases in melt flow index, tensile strength, and impact energy, while significantly enhancing density, water absorption, and biodegradability with respect to neat PBS. Further analysis of fiber sizes revealed that increasing fiber size (from 50 to 80 μm) results in a non-significant decrease in melt flow index, tensile strength, density, impact energy, water absorption, and biodegradation rates. These findings suggest that while the addition of natural fibers compromises mechanical properties, it significantly improves the environmental attributes of the composites, like water absorption and biodegradation (p<0.05). Fibers with a smaller diameter are preferable for maintaining mechanical integrity, while fibers with a larger diameter enhance biodegradability. The paper provides valuable insights into the development of a biocomposite material that balances mechanical performance with environmental sustainability.

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 demand for face masks is increasing exponentially due to the coronavirus pandemic and issues associated with airborne particulate matter (PM). However, both conventional electrostatic‐ and nanosieve‐based mask filters are single‐use and are not degradable or recyclable, which creates serious waste problems. In addition, the former loses function under humid conditions, while the latter operates with a significant air‐pressure drop and suffers from relatively fast pore blockage. Herein, a biodegradable, moisture‐resistant, highly breathable, and high‐performance fibrous mask filter is developed. Briefly, two biodegradable microfiber and nanofiber mats are integrated into a Janus membrane filter and then coated by cationically charged chitosan nanowhiskers. This filter is as efficient as the commercial N95 filter and removes 98.3% of 2.5 µm PM. The nanofiber physically sieves fine PM and the microfiber provides a low pressure differential of 59 Pa, which is comfortable for human breathing. In contrast to the dramatic performance decline of the commercial N95 filter when exposed to moisture, this filter exhibits negligible performance loss and is therefore multi‐usable because the permanent dipoles of the chitosan adsorb ultrafine PM (e.g., nitrogen and sulfur oxides). Importantly, this filter completely decomposes within 4 weeks in composting soil. An eco‐friendly face mask filter with high‐level functionality is developed. Made only of biodegradable materials, it completely decomposes in the soil, thereby providing a fundamental waste problem solution. Moreover, the filter is a practical alternative to conventional disposable filters by integrating the physical sieving role of a poly(butylene succinate) fiber mat and the permanent electrostatic adsorption roles of chitosan nanowhiskers.

Biopolymers, especially poly(lactic acid) (PLA), have been among major 3D-printing materials, particularly for fused deposition modelling (FDM) techniques. Blending of PLA with poly(butylene succinate) (PBS) can enhance toughness. The blend can be reinforced by the addition cellulose nanofibrils (CNF), which has been rarely studied. A 1% solution of CNF was added to PLA/PBS with ratio of 70:30 directly during melt-blending into 3D-printing filament, which was fed into a FDM 3D printer. Characterization by Fourier transform infrared spectroscopy revealed successful integration of CNF fillers with more hydroxyl group availability in the composite. The degree of crystallinity of PLA, however, was decreased by addition of CNF fillers. This was also evident by the X-ray diffraction analysis, probably due to reduced chain mobility by entanglement effect. Mechanical performance of the printed samples was studied at 23 °C and at slightly elevated temperature of 40 °C, which revealed improved modulus and elongation stability at 40 °C in PLA/PBS-CNF1% composite. Water absorption study also revealed 50% enhancement with addition of CNF fillers, indicating improved water penetration, which could be beneficial for biodegradability. With good mechanical stability at around 40 °C and good water penetration, PLA/PBS-CNF1% composite could be beneficial in 3D-printing for biomedical application and water treatment.

The production of bio-based composites with enhanced characteristics constitutes a strategic action to minimize the use of fossil fuel resources. The mechanical performances of these materials are related to the specific properties of their components, as well as to the quality of the interface between the matrix and the fibers. In a previous research study, it was shown that the polarity of the matrix played a key role in the mechanisms of fiber breakage during processing, as well as on the final properties of the composite. However, some key questions remained unanswered, and new investigations were necessary to improve the knowledge of the interactions between a lignocellulosic material and a polar matrix. In this work, for the first time, atomic force microscopy based on force spectroscopy measurements was carried out using functionalized tips to characterize the intermolecular interactions at the single molecule level, taking place between poly(butylene succinate) and four different plant fibers. The efficiency of the tip functionalization was checked out by scanning electron microscopy and energy-dispersive X-ray spectroscopy, whereas the fibers chemistry was characterized by Fourier-transform infrared spectroscopy. Larger interactions at the nanoscale level were found between the matrix and hypolignified fibers compared to lignified ones, as in control experiments on single lignocellulosic polymer films. These results could significantly aid in the design of the most appropriate composite composition depending on its final use.