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Highlights The objective of this study is to improve the properties of polylactic acid (PLA), a biopolymer produced from renewable resources, without compromising its environmentally friendly “natural composite” properties. The aim was to expand the application range of PLA by making it suitable for the production of high performance composites. With this in mind, it was decided to use inorganic and environmentally friendly materials such as basalt fiber (BF) and boric acid (BA) as reinforcements. Adhesive wear and tensile tests were used to investigate the tribological and mechanical performance of the composites. Differential scanning calorimetry (DSC) and dimensional stability analysis (DSA) methods were used to investigate the thermal properties. Scanning electron microscopy analysis was also used to investigate the morphological properties of the samples. In addition, a matrix modification process using Joncryl®, an epoxy‐based chain extender chemical, was applied to enhance the interfacial interaction between the composite components and improve the composite properties by improving the dispersion of reinforcing materials. As a result of the characterization tests, it was observed that a significant improvement in the properties of the material type containing 10 wt% BF, 0.25 wt% BA and 2 wt% Joncryl® was achieved. A 19% increase in tensile strength of this type of material was observed compared with unreinforced PLA, while the sharp peak increase in the coefficient of friction (COF) curve was shifted from 20 m to 60 m. As a result, it has been presented that environmentally friendly and inorganic materials such as BF and BA can be used to produce composite materials that will serve sectors where the need and use of high performance materials is intense, especially in the automotive, aerospace and aviation sectors. The properties of PLA matrix composites were improved by the simultaneous use of BF and BA and the addition of Joncryl®. The structural properties of PLA, an environmentally friendly polymer, have been improved without compromising this characteristic. PLA matrix natural composites with performance that can be used in the automotive, aerospace and aviation sectors have been developed. [ABSTRACT FROM AUTHOR]

The use of biodegradable polymers in the plastics industry has been increasing in recent years. The study of the chemical, physical, thermal, and mechanical properties of films based on biodegradable components is of interest to technologists because these properties determine their applicability for food packaging. In this work, films based on natural polymers such as linseed mucilage (LM) and chitosan (CH), as well as poly(acrylic acid) (PAA) were obtained through the casting method and using V‐50 as the initiator. The films were characterized through Fourier Transform Infrared spectroscopy, and thermogravimetric analysis, and their water absorption and swelling capacity, and thermal and mechanical properties were determined. Homogenous flexible, translucid, amber‐colored films, with low absorption and solubility in water were obtained. It was demonstrated through Fourier Transform Infrared analysis the chemical interaction between C–H, CO, and C–O chemical groups of LM, CH, and PAA. In addition, films showed high resistance to thermal decomposition between 125 and 425°C. The mechanical tests of tension allowed the composition of LM in the film, the behavior variates between a plastic and/or elastic material and with tensile strength (Rm) values between 10.8 and 16.4 MPa and elastic modulus (E) values between 56.2 and 169.2 GPa, we observed that at higher quantities of LM and thickness, both E and Rm tend to increase, while %EL decreases. This led us to conclude that the material transitioned from ductile and malleable to rigid and brittle. The films obtained with different ratios of LM/CH/PAA may exhibit a semi‐interpenetrating polymeric networking type morphology. Highlights: Thermal and mechanical properties are of interest in food packaging materials.Water absorption can impact the packaged food.Films can be processed on existing machines for conventional plastics.Some conventional plastics could be replaced by these biodegradable films.Biodegradable films are of great interest to the industry of food packaging. [ABSTRACT FROM AUTHOR]

Polymer biocompositions of poly(3-hydroxybutyrate) (P3HB) and linear polyurethanes (PU) with aromatic rings were produced by melt-blending at different P3HB/PU weight ratios (100/0, 95/5, 90/10, and 85/15). Polyurethanes have been prepared with 4,4′-diphenylmethane diisocyanate and polyethylene glycols with molar masses of 400 g/mol (PU400), 1000g/mol (PU1000), and 1500 g/mol (PU1500). The compatibility and morphology of the obtained polymer blends were determined by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). The effect of the polyurethane content in the biocompositions on their thermal stability and mechanical properties was investigated and compared with those of the native P3HB. It was shown that increasing the PU content in P3HB-PU compositions to 10 wt.% leads to an improvement in the mentioned properties. The obtained results demonstrated that the thermal stability and mechanical properties of P3HB were improved, particularly in terms of increasing the degradation temperature, reducing hardness, and increasing impact strength. The best thermal and mechanical properties were shown by the P3HB-PU polymer compositions containing 10 wt.% of polyurethane modifiers, especially PU1000, which was also confirmed by the morphology analysis of these biocompositions. The presence of polyurethanes in the resulting polymer biocomposites decreases their glass transition temperatures, i.e., makes the materials more flexible. The resulting polymer biocompositions have suitable mechanical properties and thermal properties within the processing conditions for the predicted application as biodegradable, short-lived products for agriculture. [ABSTRACT FROM AUTHOR]

Tamarind seed polysaccharides (TSPs), in conjunction with alkali nitrate, specifically lithium nitrate (LiNO3), were utilized at various concentrations. The aforementioned precursor was dispersed in an aqueous solvent medium using the solution casting route to synthesize thin film polymer electrolytes based on TSP:LiNO3. A comprehensive characterization, incorporating X-ray diffraction (XRD), Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), impedance analysis, and linear sweep voltammetry (LSV), was conducted to elucidate key properties, including crystallinity state (crystalline or amorphous), vibrational band shifts, endothermic point characteristics, ionic conductivity, mobility (both cationic and anionic), diffusion coefficients (both cation and anion), transference number, and electrochemical stability. The investigation revealed that the structural properties of the polymer electrolytes are notably influenced by the varying concentrations of LiNO3 in the polymer host. The maximum ionic conductivity was found to be 1.41 × 10−3 S cm−1 for the composition of 750 mg TSP:250 mg LiNO3. The electrochemical stability value and transference number of the prepared TSP:LiNO3 are 4 V and 0.68, respectively. Primary lithium-ion cell has been constructed for highest conducting sample which delivered an open circuit voltage of 1.5 V, and also, the discharge profile with 1 MΩ load has been studied. [ABSTRACT FROM AUTHOR]

Biopolymer blend composite films based on polyvinyl alcohol (PVA) and chitosan (CS) incorporated with varying amounts of chicory extract (CE) have been developed by the green solution casting technique. The impact of CE content on structural, thermal, mechanical and electrical properties was thoroughly examined. The existence of intermolecular interactions in the blend composite was confirmed by Fourier‐transform infrared and ultraviolet spectroscopy. The x‐ray diffraction pattern proved the successful preparation of PVA/CS/CE composite film. The scanning electron microscopy images of the composites showed shape and grain size for the different bio‐filler contents. The thermal transition temperature of the blend composites was significantly improved by the addition of CE extract deduced from differential scanning calorimetry. The dielectric study showed that the permittivity remarkably increases with decreasing frequency and maximum dielectric constant was observed for 15 wt% loading. The activation energy obtained from the AC conductivity decreased as the temperature increased. The addition of CE extract improved the hardness and tensile strength of the PVA/CS blend composite in comparison with a pristine pure blend. The controllable mechanical, thermal, optical, and electrical characteristics of the PVA/CS blend composite suggest that it might be an attractive optical material for the advancement of futuristic flexible‐type optoelectronic and energy storage systems. [ABSTRACT FROM AUTHOR]

Medicated jellies are widely used by a large part of patients, especially by people with swallowing difficulties. Preformulation studies play an essential role in the development of new pharmaceutical formulations. The present study aimed to formulate and evaluate medicated jellies containing perphenazine, an antipsychotic drug from the group of phenothiazine compounds used to treat schizophrenia and other mental disorders. Typical gelling agents such as sodium alginate (Alg), gelatine (Gel), and pectin (Pec) were used to develop the medicated jellies. In addition to the biopolymers, components such as benzoic acid (BenzAc), citric acid (CitAc), sodium citrate (NaCit), sorbitol (Sorb) and xylitol (Xyl) were also used. Before preparing the jellies, the moist binary mixture between each component of the jelly and the active substance was analysed to investigate the compatibility of the substances. The active substance, moist binary mixture, and medicated jellies were analysed by FTIR_UATR spectroscopy, UV-Vis spectroscopy and thermogravimetry. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of the ozone treatment of film-forming solutions (FFSs) containing whey protein concentrate (WPC) and gelatine on biopolymer films' physical, mechanical, and thermal properties. Film samples were produced from a FFS that was ozone-treated at 0 (control), 5, 10, and 30 min. Ozone treatment caused an increase in the pH values of the FFS, whereas the zeta potential remained negative. The films became lighter in colour, slightly greenish, and more opaque with longer ozonation times. The control sample showed the highest thermogravimetric weight loss (92.15%). The weight loss of the samples decreased with increasing ozone treatment time. The application of ozone treatment on the FFS enhanced the films' mechanical properties. Increased ozone treatment time improved the film samples' tensile strength, elongation at break, and toughness values. In conclusion, the results of this study demonstrate that the ozone treatment of FFS containing whey protein concentrate and gelatine can significantly enhance the physical, mechanical, and thermal properties of biopolymer films. These results highlight the potential of ozone treatment as a viable method for improving the performance and quality of biopolymer films used in food packaging, offering promising advantages for sustainable and environmentally friendly packaging solutions. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the morphological and thermo-mechanical properties of a bioplastc film obtained from orange peel. Design/methodology/approach: Pectin, a polysaccharide obtained from orange peel, has the potential to be used as a raw material in the bioplastics industry. The samples obtained were characterized by the Scanning Electron Microscopy (SEM) technique, mechanical tension and by thermogravimetric analysis (TGA). Results: The elastic modulus was in the range of 7.7 to 29.9 MPa, depending on the plasticizer content. The thermogravimetric analysis showed a thermal decomposition between 134.42 to 153.98 °C depending on the plasticizer content and up to five events were identified. Limitations of the study/implications: During the process, a pectin yield of 75% of orange peel was obtained. Findings/conclusions: In developing countries such as Mexico, waste from agricultural and agro-industrial activities represents an important source of natural carbohydrate polymers that can be used to produce bioplastics, intended to replace petroleum-derived materials. In the case of orange peel, it can become a potential raw material to obtain value-added products in sectors of the food industry. These results indicated that our pectin has suitable properties to be used as raw material for the manufacture of bioplastics. [ABSTRACT FROM AUTHOR]

• Tannic acid is neither a good flame retardant nor a highly swelling material. • TA combined with CLS reduces flammability of biocomposite by 30 % compared to PLA. • Mixing of TA with CLS in melt doesn't allow for PHRR reduction of more than 20 %. The purpose of this study was to determine the quantitative and qualitative effects of the form of natural phenolic compounds (NPCs) on the decomposition of polylactide (PLA) under different measurement conditions. For this purpose, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), and pyrolysis-combustion flow calorimetry (PCFC) analyses were carried out not only on individual raw materials like calcium lignosulfonate (BX), tannic acid (TA), BX chemically modified with TA (BMT), but also on PLA/BX, PLA/TA, and PLA/BMT composites with 3, 6, and 9 wt.% of filler. Moreover, the work checked whether to obtain satisfactory results it is necessary to carry out chemical modification lasting many hours, or whether simple physical mixing of ingredients (TABX) is enough, e.g. in proportions 1:2, 2:4, 3:6. The results of these analyses showed that TA is neither a good flame retardant nor a highly swelling material, but when combined with BX physically or chemically, it can produce an interesting synergistic effect. This work proves that chemically obtained BMT hybrid material allows to reduce flammability by 30 % compared to PLA which cannot be achieved by physically mixing these components in a polymer melt. On the other hand, the addition of TABX is sufficient to achieve a good thermal stabilization effect under processing conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to produce new nanocomposites with antimicrobial, antioxidant and anticancer properties that can be used in biomedical research based on carboxymethyl cellulose (NaCMC) biopolymer. First, poly(2-oxo-2-(pentafluorophenoxy)ethyl-2-methylprop-2-enoate) (PPFMA) was synthesized and characterized by FTIR and NMR techniques. It was then blended with NaCMC by in situ/hydrothermal method to produce a semi-synthetic functional material. Changes in the FTIR data of the blend and the single Tg value from DSC confirmed the compatibility of the blend. To enhance the thermal and biological properties of the NaCMC-PPFMA blend, biosynthesized Ag-ZnONPs were hydrothermally incorporated into the blend at different weight ratios. The prepared materials were characterized by SEM, EDX, TEM, XRD and FTIR. The thermal stability of the materials was determined by thermogravimetric analysis (TGA), and glass transition temperatures (Tg) was determined by differential scanning calorimeter (DSC). The oxidant, antioxidant, antimicrobial, and cytotoxic properties of PPFMA, Ag-ZnONPs, PPFMA-NaCMC blend, and nanocomposites were investigated in detail. The total oxidant state (TOS) value of the NaCMC-PPFMA blend, which was 0.72 μmol equivalent H 2 O 2 /L, increased to 7.2–10.4 μmol equivalent H 2 O 2 /L with the addition of Ag-ZnONPs. Ag-ZnONPs decreased total antioxidant state (TAS) levels of the nanocomposites while increasing their oxidant activity. Therefore, an increase in the antimicrobial activity of the nanocomposites was observed. Adding Ag-ZnONPs to the NaCMC-PPFMA blend increased the thermal stability by 22 °C and the Tg value by 9 °C. Finally, the potential of Ag-ZnONPs containing nanocomposites in wound healing therapies was examined. The findings suggest that nanocomposites prepared by incorporating Ag-ZnONPs into the semi-synthetic NaCMC-PPFMA blend can be a source of bio-safe raw materials and can be used as potential wound healers. [ABSTRACT FROM AUTHOR]