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1.
Heliyon ; 10(17): e37255, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39296210

RESUMEN

Renewable lignocellulosic biomass is a favorable energy resource since its co-pyrolysis with hydrogen-rich plastics can produce high-yield and high-quality biofuel. In contrast to earlier co-pyrolysis research that concentrated on increasing product yield, this study comprehends the synergistic effects of two distinct feedstocks that were not considered earlier. This work focuses on co-pyrolyzing wheat straw (WS) with non-reusable polyethylene terephthalate (PET) for the production of pyrolysis oil. WS and PET were blended in different ratios (100/0, 80/20, 60/40, 40/60, 20/80, and 0/100), and pyrolysis experiments were conducted in a fixed-bed reactor under different temperatures to assess their synergistic effect on oil yield. Synergy rates of up to 7.78 % were achieved on yield for the blends of plastic and biomass at a temperature of 500 °C. In comparison to individual biomass or plastics, co-pyrolyzing PET-biomass blends demonstrated good process interaction and promoted the yields of value-added products. The heating value of the pyrolysis oils was in the range of 16.45-28.64 MJ/kg, which depends on the amount of plastic present in the feedstock. The physical analysis of the oils shows that they can be used for heat production by direct combustion in boilers or furnaces. The correlation between WS and PET was validated with the aid of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) analysis. The GC-MS result demonstrated the presence of different compounds such as O-H compounds, esters, carbonyl group elements, acids, hydrocarbons, aromatics, and nitrogenated compounds in the pyrolysis oil, which differed based on the proportions of PET in the feedstock. The increased hydrocarbon and reduced oxygen percentages in the pyrolysis oil were implicitly caused by enhanced hydrocarbon pool mechanisms, in which the breakdown of PET may be supplied as a hydrogen donor. Overall, waste lignocellulosic biomass and plastics can be used to produce biofuels, which helps reduce the amount of solid waste that ends up in landfills. This study also revealed that future research should be focused on the reaction mechanisms of WS and PET co-pyrolysis in order to examine the synergistic interactions.

2.
Biomed Mater ; 19(6)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39255825

RESUMEN

Bioengineered vascular grafts (VGs) have emerged as a promising alternative to the treatment of damaged or occlusive vessels. It is thought that polyurethane (PU)-based scaffolds possess suitable hemocompatibility and biomechanics comparable to those of normal blood vessels. In this study, we investigated the properties of electrospun scaffolds comprising various blends of biostable polycarbonate-based PU (Carbothane™ 3575A) and gelatin. Scaffolds were characterized by scanning electron microscopy, infra-red spectroscopy, small-angle x-ray scattering, stress-loading tests, and interactions with primary human cells and blood. Data fromin vitroexperiments demonstrated that a scaffold produced from a blend of 5% Carbothane™ 3575A and 10% gelatin has proven to be a suitable material for fabricating a small-diameter VG. A comparativein vivostudy of such VGs and expanded polytetrafluoroethylene (ePTFE) grafts implanted in the abdominal aorta of Wistar rats was performed. The data of intravital study and histological examination indicated that Carbothane-based electrospun grafts outclass ePTFE grafts and represent a promising device for preclinical studies to satisfy vascular surgery needs.


Asunto(s)
Prótesis Vascular , Ensayo de Materiales , Poliuretanos , Ratas Wistar , Andamios del Tejido , Animales , Ratas , Poliuretanos/química , Humanos , Andamios del Tejido/química , Aorta Abdominal/cirugía , Materiales Biocompatibles/química , Politetrafluoroetileno/química , Gelatina/química , Masculino , Cemento de Policarboxilato/química , Microscopía Electrónica de Rastreo , Ingeniería de Tejidos/métodos
3.
Trop Anim Health Prod ; 56(7): 255, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240410

RESUMEN

This study aimed to evaluate the impact of supplementing sodium bicarbonate or a commercial blend of buffering agents (BBA) comprising calcareous calcitic, magnesium oxide, calcareous algae, and sodium bicarbonate on the productive, behavioral and metabolic parameters of Holstein cows fed starchy diets. Over a 60-day trial period, thirty-six multiparous cows with an average milk yield of 38.84 ± 9.24 kg/day and 63.74 ± 18.63 days in milk (DIM), were randomly divided into two groups. The control group (n = 18) received a supplementation of 1.1% dry matter (DM) of sodium bicarbonate (Raudi®, Totalmix, Brazil), while the BBA group (n = 18) was administered with 0.5% DM of a blend of buffering agents (Equalizer®, Nutron/Cargill, Brazil). The mean values of ruminal pH (control 6.80 ± 0.06 and BBA 6.77 ± 0.06; P > 0.05) and volatile fatty acid (VFA) production (control: acetate 62.63 ± 1.29%, propionate 22.99 ± 1.07%, butyrate 14.30 ± 0.52%; BBA: acetate 63.07 ± 1.32%, propionate 23.47 ± 1.10%, butyrate 13.70 ± 0.57%), were similar (P > 0,05) between the two groups. The value of faecal pH was higher (P < 0.05) in the BBA group (6.25 ± 0.02) than the control group (6.12 ± 0.02). Animals treated with BBA exhibited lower (P < 0,05) dry matter intake (DMI) (24.75 ± 0.64 kg/day), higher feed efficiency (FE) (1.64 ± 0.03), and reduced feeding frequency (52.89 ± 3.73 n°/day) than the control group (DMI, 26.75 ± 0.62 kg/day; FE, 1.50 ± 0.03; feeding frequency, 66.07 ± 3.64 n°/day). Milk production remained similar across both groups (control, 39.11 ± 0.92 kg/day and BBA, 39.87 ± 0.92 kg/day; P > 0.05). Notably, the control group displayed a higher (P < 0,05) concentration of milk protein (1.21 ± 0.05 kg/day) than the BBA (1.18 ± 0.05 kg/day) group. The study concluded that both treatments effectively buffered the rumen and mitigated the risk of ruminal acidosis. Moreover, the higher faecal pH in the BBA-treated group suggests potential intestinal action attributable to the synergistic effects of diverse additives with buffering properties. Despite a reduced DMI, BBA-treated animals exhibited improved FE.


Asunto(s)
Alimentación Animal , Dieta , Lactancia , Rumen , Animales , Bovinos/fisiología , Femenino , Lactancia/efectos de los fármacos , Dieta/veterinaria , Rumen/metabolismo , Rumen/efectos de los fármacos , Alimentación Animal/análisis , Suplementos Dietéticos/análisis , Leche/química , Tampones (Química) , Bicarbonato de Sodio/administración & dosificación , Bicarbonato de Sodio/farmacología , Ácidos Grasos Volátiles/metabolismo , Ácidos Grasos Volátiles/análisis , Distribución Aleatoria , Concentración de Iones de Hidrógeno , Conducta Animal/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Brasil
4.
Polymers (Basel) ; 16(17)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39274112

RESUMEN

Four non-fluorinated sulfonimide polyamides (s-PAs) were successfully synthesized and a series of membranes were prepared by blending s-PA with polyvinylidene fluoride (PVDF) to achieve high-methanol-permeation resistivity for direct methanol fuel cell (DMFC) applications. Four membranes were fabricated by blending 50 wt% PVDF with s-PA, named BPD-101, BPD-102, BPD-111 and BPD-211, respectively. The s-PA/PVDF membranes exhibit high methanol resistivity, especially for the BPD-111 membrane with methanol resistivity of 8.13 × 10-7 cm2/s, which is one order of magnitude smaller than that of the Nafion 117 membrane. The tensile strength of the BPD-111 membrane is 15 MPa, comparable to that of the Nafion 117 membrane. Moreover, the four membranes also show good thermal stability up to 230 °C. The BPD-x membrane exhibits good oxidative stability, and the measured residual weights of the BPD-111 membrane are 97% and 93% after treating in Fenton's reagent (80 °C) for 1 h and 24 h, respectively. By considering the mechanical, thermal and dimensional properties, the polyamide proton-exchange membrane exhibits promising application potential for direct methanol fuel cells.

5.
Int J Biol Macromol ; 279(Pt 3): 135345, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39244110

RESUMEN

Plasticized PLA plastic films are being increasingly used in, among others, packaging and agriculture sectors in an attempt to address the rapid growth of municipal waste. The present paper aims to review the recent progress and the state-of-the-art in the field of fully bio-renewable tough blends of PLA with green plasticizers aimed at developing flexible packaging films. The different classes of green substances, derived from completely bio-renewable resources, used as potential plasticizers for PLA resins are reviewed. The effectiveness of these additives for PLA plasticization is discussed by describing their effects on different properties of PLA. The performance of these blends is primarily determined by the solvent power, compatibility, efficiency, and permanence of plasticizer present in the PLA matrix of resulting films. The various chemical modification strategies employed to tailor the phase interactions, dispersion level and morphology, plasticization efficiency, and permanence, including functionalization, oligomerization, polymerization and self-crosslinking, grafting and copolymerization, and dynamic vulcanization are demonstrated. Sometimes a third component has also been added to the plasticized binary blends as compatibilizer to further promote dispersion and interfacial adhesion. The impact of chemical structure, size and molecular weight, chemical functionalities, polarity, concentration, topology as well as molecular architectures of the plasticizers on the plasticizer performance and the overall characteristics of resulting plasticized PLA materials is discussed. The morphological features and toughening mechanisms for PLA/plasticizer blends are also presented. The different green liquids employed show varying degree of plasticization. Some are more useful for semi-rigid applications, while some others can be used for very flexible products. There is an optimum level of plasticizer in PLA matrices above which the tensile ductility deteriorates. Esters-derivatives of bio-based plasticizers have been shown to be very promising additives for PLA modification. Some plasticizers impart additional functions such as antioxidation and antibacterial activity to the resulting PLA materials, or compatibilization in PLA-based blends. While the primary objective of plasticization is to boost the processability, flexibility, and toughness over wider practical conditions, the bio-degradability, permeability and long-term stability of microstructure (and thereby properties) of the plasticized films against light, weathering, thermal aging, and oxidation deserve further investigations.

6.
Food Sci Biotechnol ; 33(13): 3057-3065, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39220320

RESUMEN

This study investigated the suitability of a potato starch (NP)-Dodamssal rice starch (DD) mixture to replace acetylated potato starch (AP) in long-life noodles. Wheat flour (WF) was replaced with AP and NP in 20% of WF, and NP was replaced with DD in 10-50% of NP. The swelling power of the WF-AP mixture was similar to that of all the WF-NP-DD mixtures. The melting enthalpies of the WF-NP-DD mixtures were slightly higher than those of the WF-AP mixtures. The pasting viscosity decreased with increasing DD content of the mixtures. The G' of all the WF-NP-DD mixtures was higher than that of the WF-AP mixture over the temperature profile, and similar G' patterns over time were observed. The tensile strengths of noodles by the WF-NP-DD mixtures were similar to those obtained using the WF and WF-AP mixture. Overall, NP-DD mixtures have the potential to replace AP when mixed with WF. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-024-01628-7.

7.
Eur J Pharm Sci ; 202: 106890, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39214317

RESUMEN

The continuous feeding-mixing system ensures the composition uniformity down to the tableting continuous manufacturing line so that a quality end-product is consistently delivered. Near-infrared spectroscopy (NIRS) enables in-line assessment of the blend's critical quality attributes in real-time. In this study, the effect of total feed rate and impeller speed on the continuous blending process monitored in-line by NIRS was examined by principal component analysis (PCA), ANOVA simultaneous component analysis (ASCA) and partial least squares (PLS) regression. Process data were generated by a factorial experimental design with process parameters and a constant formulation comprised of: 30 % (wt/wt) ibuprofen, 67.5 % (wt/wt) microcrystalline cellulose, 2 % (wt/wt) of sodium starch glycolate and 0.5 % (wt/wt) of magnesium stearate. The PCA hinted at the prevalence of impeller speed effect on ibuprofen concentration due to path length variation of the NIR light caused by the fluidized behaviour in the powder blend as a result of high speed ranges (>300 rpm). The ASCA model indicated that while both impeller speed and total feed rate effects were statistically significant (p-value=0.004), the impeller speed was the factor that contributed the most to the spectral variance (55.5 %). The PLS regression model for the ibuprofen content resulted in a RMSECV of 1.3 % (wt/wt) and showed that impeller speed was yet again the factor that exerted the major influence on spectral variance, owing to its wavelength-dependent effect that prevents common pre-processing techniques from eliminating it across the entire NIR range. The best sample presentation to the NIR probe was achieved at low impeller speed ranges (<600 rpm) and low total feed rates (<15 kg/h), such that it enhanced the PLS model ability to predict the ibuprofen concentration in the blend.


Asunto(s)
Celulosa , Ibuprofeno , Análisis de Componente Principal , Espectroscopía Infrarroja Corta , Ácidos Esteáricos , Espectroscopía Infrarroja Corta/métodos , Ibuprofeno/química , Celulosa/química , Ácidos Esteáricos/química , Análisis de los Mínimos Cuadrados , Almidón/química , Almidón/análogos & derivados , Excipientes/química , Comprimidos , Composición de Medicamentos/métodos
8.
Int J Biol Macromol ; 278(Pt 3): 134769, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39151866

RESUMEN

Heavy metal pollution poses a significant environmental challenge to worldwide, especially in developing countries. This study focuses on eliminating the heavy metal chromium (VI) ion from wastewater, employing an eco-friendly and economical ternary blend composed of Chitosan (CS), Carboxymethyl cellulose (CMC), and bioactive glass (BAG). The innovative bioactive glass is crafted from biosilica extracted from biowaste of cow dung ash, calcium oxide from eggshell ash, and phosphorus pentoxide. The CS/CMC/BAG blend is prepared via sol-gel method and characterized using XRD, FT-IR, TGA, BET, TEM and SEM revealing a porous structural morphology during blending. Batch adsorption studies explore various parameters such as pH, adsorbent dose, contact time and initial metal ion concentrations. The results are then evaluated through adsorption kinetics and adsorption isotherms (Langmuir, Freundlich, D-R, and Temkin isotherm modeling). The investigation concludes that the optimal conditions for Cr (VI) removal are pH 3, contact time of 300 min, adsorbent dosage of 0.5 g, and an initial metal ion concentration of 50 ppm. The adsorption isotherm model indicates an excellent fit with the Freundlich isotherm (R2 = 0.9576) and pseudo-second-order kinetics (R2 = 0.981). In summary, the CS/CMC/BAG ternary blend exhibits a remarkable ability to effectively remove heavy metal Cr(VI) ions from industrial wastewater.


Asunto(s)
Carboximetilcelulosa de Sodio , Quitosano , Cromo , Vidrio , Contaminantes Químicos del Agua , Quitosano/química , Carboximetilcelulosa de Sodio/química , Cromo/química , Adsorción , Vidrio/química , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno , Purificación del Agua/métodos , Aguas Residuales/química , Metales Pesados/química
9.
Int J Biol Macromol ; 277(Pt 3): 134287, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39095274

RESUMEN

Concerned about water treatment, it is of great importance to present new approaches for improving photocatalytic activity. Since photocatalysis is ubiquitous in almost all chemical manufacturing processes, the development of photocatalytic systems carries significance for our environment. In this regard, three different amounts of covalent organic frameworks decorated with titanium(IV) oxide nanoparticles (TiO2/COF hybrids) in Alginate-Carboxymethyl cellulose (Alg-CMC) blend matrix were prepared under ultrasound irradiation, which Citric acid and Calcium chloride acted as two green cross-linkages. Based on the physio-chemical analyses of these bio-nanocomposite (bio-NC) beads, the Alg-CMC blend polymer appeared to be the best candidate for a disparity of TiO2/COF hybrids. Not only did COF aid to increase the distribution of TiO2 nanoparticles, but it declined the bandgap energies. The resultant Alg-CMC/TiO2/COF (TiO2/COF = 15:6) bio-NC beads demonstrated efficient photodegradation activity towards Methyl violet (MV) under Ultraviolet light. The obtained results of scavenger studies indicated that superoxide radicals and electron agents played a major role in MV degradation. Further investigation confirmed that single oxygen addition and N-de-methylation could be two important pathways for the decomposition of MV by these bio-NC beads.


Asunto(s)
Alginatos , Carboximetilcelulosa de Sodio , Violeta de Genciana , Nanocompuestos , Fotólisis , Titanio , Rayos Ultravioleta , Titanio/química , Alginatos/química , Nanocompuestos/química , Carboximetilcelulosa de Sodio/química , Violeta de Genciana/química , Estructuras Metalorgánicas/química , Catálisis , Microesferas
10.
Int J Biol Macromol ; 279(Pt 1): 135122, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39208891

RESUMEN

High-performance poly(lactic acid) (PLA) blend-based composites were fabricated with a poly(ether-block-amide) (PEBA) elastomer acting as the blend counterpart. It was confirmed that a compatibilizer (ADR) enhanced the interaction between PLA and PEBA. Carbon nanotubes (CNTs) and organoclay (30B) were added individually and simultaneously into the blend to produce bionanocomposites. Morphological results showed that CNTs were mainly dispersed in PEBA domains, whereas 30B was mainly localized at the interfacial region of PLA and PEBA phases. The selective localization of added CNTs and 30B led to significant modification of the properties of the compatibilized PLA/PEBA blend. The brittleness and flammability of PLA were evidently improved after forming the bionanocomposites. Differential scanning calorimetry results revealed that CNTs and 30B assisted the crystallization of both PLA and PEBA in the composites, with CNTs providing superior nucleation efficiency to 30B. Thermogravimetric analysis revealed the thermal stability enhancement of the blend after adding CNTs and/or 30B, with up to 16 °C increase at 20 wt% loss with inclusion of 2 phr 30B. Addition of CNTs and/or 30B improved the blend's anti-dripping performance during burning tests, and CNT exhibited better anti-dripping efficiency. Ductility of PLA was drastically improved after forming the compatibilized blend, and further improved with incorporation of CNTs and/or 30B (increased from 9 % for neat PLA to 252 % for the hybrid composite containing CNT/30B). The impact strength of 1 phr CNTs-added composite was about 3 times that of PLA. Rheological properties indicated the (pseudo)network formation of added filler(s), leading to a significant reduction in electrical resistivity, up to six orders of magnitude with addition of 3 phr CNTs.

11.
Molecules ; 29(16)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39202947

RESUMEN

A traditional phase transformation method is commonly used to prepare molecular imprinting membranes for selective separation. However, traditional molecularly imprinted polymers are mostly micron-sized particles, and the imprinting sites in their membrane are easily embedded, leading to a reduced adsorption capacity and decreased selectivity. In this study, an ultra-long nanowire with a diameter of about 15 nm was synthesized for the separation of artemisinin (ART), and its adsorption capacity was as high as 198.29 mg g-1 after imprinting polymerization. Molecular imprinting membranes were prepared, using polyvinylidene fluoride (PVDF), polyethersulfone (PES), and polysulfone (PSF) as the membrane matrix, for comparison. The average membrane pore size of PVDF-MIM was about 480 nm, and PVDF-MIM had the highest adsorption capacity (69 mg g-1) for ART. The optimal flow rate for PVDF-MIM's dynamic adsorption of ART was 7 mL min-1. Under this optimal flow rate, selectivity experiments were carried out to obtain the separation factor of PVDF-MIM (α = 8.37), which was much higher than the corresponding values of PES-MIM and PSF-MIM. In addition, the hydrophobicity and low flux of PES-MIM and PSF-MIM lead to higher non-specific adsorption. The hydrophobicity of PVDF-MIM is lower than that of PES-MIM and PSF-MIM, which greatly reduces the non-specific adsorption of the membrane, thus increasing the selectivity of the membranes. Therefore, the effective density of the imprinting sites in the pores and the membrane structure are the main factors determining the efficient separation of molecularly imprinted membranes.

12.
Polymers (Basel) ; 16(16)2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39204488

RESUMEN

Biodegradable polymers and their blends have been advised as an eco-sustainable solution; however, the generation of microplastics (MPs) from their degradation in aquatic environments is still not fully grasped. In this study, we investigated the formation of bio-microplastics (BMPs) and the changes in the physicochemical properties of blown packaging films based on polylactic acid (PLA), polybutylene succinate (PBS) and a PBS/PLA 70/30 wt% blend after degradation in different aquatic media. The tests were carried out in two temperature/light conditions to simulate degradation in either warm water, under sunlight exposure (named Warm and Light-W&L), and cold deep water (named Cold and Dark-C&D). The pH changes in the aqueous environments were evaluated, while the formed BMPs were analyzed for their size and shape alongside with variations in polymer crystallinity, surface and mechanical properties. In W&L conditions, for all the films, the hydrolytic degradation led to the reorganization of the polymer crystalline phases, strong embrittlement and an increase in hydrophilicity. The PBS/PLA 70/30 blend exhibited increased resistance to degradation with respect to the neat PLA and PBS films. In C&D conditions, no microparticles were observed up to 12 weeks of degradation.

13.
Polymers (Basel) ; 16(16)2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39204545

RESUMEN

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a very promising biodegradable copolyester of high interest in food packaging. Its inherent brittleness and narrow processing window make it necessary to blend it with flexible biopolyesters, such as poly(butylene succinate-co-adipate) (PBSA). However, the resultant biopolyester blends are thermodynamically immiscible, which impairs their performance and limits their applications. This study is the first to explore the use of poly(butylene succinate-co-adipate) grafted with maleic anhydride (PBS-g-MAH) as a novel reactive additive to compatibilize PHBV/PBSA blends. The compatibilizer was prepared by a reactive melt-mixing process of PBSA and maleic anhydride (MAH) using dicumyl peroxide (DCP) as an organic radical initiator, achieving a grafting degree (Gd) of 5.4%. Biopolyester blend films were thereafter prepared via cast extrusion and their morphological, thermal, mechanical, and barrier properties were characterized. Compatibilization by PBSA-g-MAH was confirmed by observing an improved phase interaction and lower dispersed domain sizes in the blends with 15 wt% PBSA. These compatibilized PHBV/PBSA blends were thermally stable up to 285 °C, showed enhanced ductility and toughness, as well as providing an improved barrier against water and limonene vapors and oxygen. These findings suggest that the use of MAH-grafted biopolyesters can represent an effective strategy to improve the properties of biopolyester blends and open up new opportunities for the application of PHBV-based formulations for food packaging.

14.
Polymers (Basel) ; 16(16)2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39204552

RESUMEN

In a miscible crystalline/crystalline blend of poly(trimethylene terephthalate) (PTT) and poly(ethylene terephthalate) (PET), the PET spherulites grew at 240 °C when the PTT content was 30 wt% or less. The growth rate of PET spherulites decreased with time due to the exclusion of PTT from the growth front of PET spherulites into the amorphous region, resulting in a three-stage crystallization process. Due to the exclusion, the spherulite growth stopped before the volume filling of the PET spherulites, causing the formation of an excluded PTT amorphous region. When the temperature was lowered from 240 °C to 210 °C, the PTT spherulites grew in the excluded PTT amorphous region. The spherulite growth rate of PTT in the excluded PTT amorphous region was equivalent to that of a blend of 60-70 wt% PTT in 30/70 PTT/PET. These results suggest a significant change in the PTT concentration in the amorphous region, from the initial PTT content of 30 wt% to 60-70 wt%, due to the exclusion of PTT during the melt crystallization of PET at 240 °C.

15.
Polymers (Basel) ; 16(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39204606

RESUMEN

Amid the current environmental crisis caused by plastic accumulation, one of the proposed solutions to manage this problem is using biodegradable polymers. However, the impact of adding biodegradable polymers to the well-established circular economy of recyclable polymers, such as HDPE, has not been fully considered. Therefore, there is a need to reconsider the way we consume, dispose of, and manage biodegradable polymers after use. This study evaluates the effect of varying the contents of a biodegradable polymer, taking poly(lactic acid) (PLA) as a model biodegradable polymer, on the thermal and mechanical properties of HDPE. The study highlights the importance of identifying and disposing of biodegradable polymers to avoid mixtures with HDPE, in order not to affect mechanical performance when considering reprocessing and a new life cycle of this conventional polymer.

16.
Natl Sci Rev ; 11(9): nwae258, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39206047

RESUMEN

This study reports the successful design and synthesis of two novel polymerized nonfused ring electron acceptors, P-2BTh and P-2BTh-F, derived from the high-performance nonfused ring electron acceptor, 2BTh-2F. Prepared via Stille polymerization, these polymers feature thiophene and fluorinated thiophene as π-bridge units. Notably, P-2BTh-F, with difluorothiophene as the π-bridge, exhibits a more planar backbone and red-shifted absorption spectrum compared with P-2BTh. When employed in organic solar cells (OSCs) with PBDB-T as the donor material, P-2BTh-F-based devices demonstrate an outstanding power conversion efficiency (PCE) of over 11%, exceeding the 8.7% achieved by P-2BTh-based devices. Furthermore, all-polymer solar cells utilizing PBDB-T:P-2BTh-F exhibit superior storage stability. Additionally, P-2BTh-F was explored as a functional additive in a high-performance binary system, enhancing stability while maintaining comparable PCE (19.45%). This strategy offers a cost-effective approach for fabricating highly efficient and stable binary and ternary organic solar cells, opening new horizons for cost-effective and durable solar cell development.

17.
Int J Biol Macromol ; 276(Pt 1): 133758, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992550

RESUMEN

In this study, a one-step extrusion method is proposed to prepare blended polylactic acid (PLA)/thermoplastic starch (TPS) using a novel plant-derived compatibilizer, pyrogallic acid (PGA), to enhance the PLA/TPS compatibility. The effects of PGA on the mechanical behavior, fractured cross-section morphology, thermal and dynamic mechanical performance, and water resistance of PLA/TPS blends were systematically studied. Results demonstrate that the addition of PGA effectively improves the compatibility between TPS and PLA, resulting in enhanced tensile strength, crystallinity, elongation at break, thermal stability, and hydrophobicity of the blends. Specifically, incorporating 1.5 phr of PGA into the blend system yields the highest values for tensile strength (23.38 MPa) and elongation at break (16.96 %), which are 24.7 % and 233.2 %, respectively, higher than those observed for pure PLA/TPS blends. Furthermore, other properties exhibit obvious improvements upon incorporation of PGA into the blends. This approach provides a promising strategy for enhancing the performance of PLA/TPS blends and expanding their applications in food packaging, agricultural film, etc.


Asunto(s)
Poliésteres , Almidón , Resistencia a la Tracción , Almidón/química , Poliésteres/química , Interacciones Hidrofóbicas e Hidrofílicas , Temperatura , Agua/química
18.
J Biomater Sci Polym Ed ; 35(13): 1963-1977, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38949409

RESUMEN

The interest in wound dressings increased ten years ago. Wound care practitioners can now use interactive/bioactive dressings and tissue-engineered skin substitutes. Several bandages can heal burns, but none can treat all chronic wounds. This study formulates a composite material from 70% polyvinyl alcohol (PVA) and 30% polyethylene glycol (PEG) with 0.2, 0.4, and 0.6 wt% magnesium oxide nanoparticles. This study aims to create a biodegradable wound dressing. A Fourier Transform Infrared (FTIR) study shows that PVA, PEG, and MgO create hydrogen bonding interactions. Hydrophilic characteristics are shown by the polymeric blend's 56.289° contact angle. MgO also lowers the contact angle, making the film more hydrophilic. Hydrophilicity improves film biocompatibility, live cell adhesion, wound healing, and wound dressing degradability. Differential Scanning Calorimeter (DSC) findings suggest the PVA/PEG combination melted at 53.16 °C. However, adding different weight fractions of MgO nanoparticles increased the nanocomposite's melting temperature (Tm). These nanoparticles improve the film's thermal stability, increasing Tm. In addition, MgO nanoparticles in the polymer blend increased tensile strength and elastic modulus. This is due to the blend's strong adherence to the reinforcing phase and MgO nanoparticles' ceramic material which has a great mechanical strength. The combination of 70% PVA + 30% PEG exhibited good antibacterial spatially at 0.2% MgO, according to antibacterial test results.


Asunto(s)
Óxido de Magnesio , Nanopartículas , Polietilenglicoles , Alcohol Polivinílico , Cicatrización de Heridas , Alcohol Polivinílico/química , Óxido de Magnesio/química , Óxido de Magnesio/farmacología , Polietilenglicoles/química , Cicatrización de Heridas/efectos de los fármacos , Nanopartículas/química , Membranas Artificiales , Resistencia a la Tracción , Antibacterianos/farmacología , Antibacterianos/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Animales , Vendajes , Adhesión Celular/efectos de los fármacos , Ensayo de Materiales , Ratones , Nanocompuestos/química
19.
Food Res Int ; 191: 114609, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059893

RESUMEN

Food waste is responsible for the loss of 1.3 billion tons of food, some of which are related to by-products with great nutritional and energy potential that are still underexplored, such as safflower cake derived from the oil extraction industry. Therefore, the aim of this study was to evaluate the effects of incorporating safflower cake (Carthamus tinctorius) and the mixing method used to produce composite wheat-based flour in order to develop a new ingredient. The results were analyzed using ANOVA, and the Tukey test was applied at a significance level of 5 %. The composite flours obtained by the conventional mixing method showed, when compared to wheat flour, a higher concentration of proteins (+5g 100 g-1), minerals (+86 mg kg-1 of Fe, +30 mg kg-1 of Zn), phenolic compounds (15 mg GAE g-1), flavonoids (0.3 mg QE g-1), and lower oil absorption (-0.5 g oil g sample-1), making them suitable for hot flour-based sauces, salad dressings, frozen desserts, cookies and fried products. While extruded composite flours presented better homogenization, reduction of moisture (1 g 100 g-1), lipids (3 g 100 g-1), and mycotoxin concentrations, increased antioxidant activity (DPPH -0.07 IC50 mg/L and ORAC +9 µmol Trolox Eq/g), water absorption and solubility indexes, and oil absorption index, making it suitable for bakery products, meat, and dairy sausages. The developed composite flour proved to be a good nutritional ingredient; thus, its consumption can represent an important nutritional strategy with low production costs, as well as a sustainable solution, reducing food waste and, therefore, toward the concepts of the circular economy.


Asunto(s)
Carthamus tinctorius , Harina , Manipulación de Alimentos , Harina/análisis , Carthamus tinctorius/química , Manipulación de Alimentos/métodos , Valor Nutritivo , Triticum/química , Ingredientes Alimentarios/análisis , Fenoles/análisis , Minerales/análisis , Minerales/química , Flavonoides/análisis
20.
Sci Rep ; 14(1): 16606, 2024 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025936

RESUMEN

The agronomic use of compost and biochar as soil amendments may exhibit contrasting results in terms of soil fertility and plant nutrition. The effects of the biennial application of biochar, compost and a blend of compost:biochar (90:10; % dw:dw) on the agronomical performance of an organically managed and well established 25-year-old olive orchard was assessed 5 years after the initial application. The agronomical evaluation was based on the assessment of the soil physical, chemical, and biological characteristics, and the assessment of the soil fertility by both crop production and nutritional status of the orchard, and the bioassay with olive plantlets. Biochar mainly benefited the physical properties (bulk density, total porosity, aeration, water retention capacity) of soil, especially in the top 0-5 cm. Compost and its blend with biochar improved microbial activity, soil nutritional status (increasing the content of soluble organic C, N, and P) and favoured the formation of aggregates in soil. The bioassay conducted with young plantlets confirmed the enhanced soil fertility status in the three amended treatments, particularly in the case of biochar and its blend with compost. However, this effect was not significantly observed in the adult plants after 5 years of application, reflecting the slow response of adult olive trees to changes in fertilization. Based on these results, alongside the desirable long-residence time of biochar in soil and the ready availability of compost, the blend of biochar with compost assayed in this study is defined as a valid strategy for preparing high quality soil organic amendments.


Asunto(s)
Carbón Orgánico , Compostaje , Olea , Suelo , Olea/crecimiento & desarrollo , Suelo/química , Compostaje/métodos , Fertilizantes/análisis , Agricultura Orgánica/métodos
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