Influence of agro-industrial wastes over the abiotic and composting degradation of polylactic acid biocomposites

2021 ◽  
pp. 002199832110476
Author(s):  
Alan S Martín del Campo ◽  
Jorge R Robledo-Ortíz ◽  
Martín Arellano ◽  
Aida A Perez-Fonseca
Keyword(s):  
Polylactic Acid ◽  
Natural Fibers ◽  
Hydrolytic Degradation ◽  
Industrial Wastes ◽  
Chemical Compositions ◽  
Accelerated Weathering ◽  
Mechanical And Thermal Properties ◽  
Remarkable Effect ◽  
Abiotic Degradation ◽  
Biotic Degradation

Combining polylactic acid (PLA) with waste fibers to produce reinforced biocomposites is of top interest to replace conventional polymers for environmentally friendlier materials. Natural fibers have a remarkable effect on the mechanical and thermal properties of the biocomposites. This reinforcing effect strongly depends on the chemical compositions of fibers, which will also influence the susceptibility of the biocomposites to abiotic and biotic degradation processes. This study evaluated the effect of agave and coir waste fibers over the abiotic and composting degradation of PLA-based biocomposites. Compression-molded PLA/agave and PLA/coir biocomposites using GMA-g-PLA as compatibilizer were subjected to accelerated weathering. Weathered and unweathered samples were further submitted to water absorption to analyze their hydrolytic degradation and composting for biotic degradation. Both fibers showed significant influence on biocomposites degradation. The role of the fibers in UV and hydrolytic degradation was positive for impact properties since the biocomposites were less affected than PLA. Water uptake was increased with fiber addition, while hydrolytic degradation was decreased. The weathering (abiotic degradation) accelerated the PLA biodegradation rate. In general, the results showed that adding both fibers to PLA could help its outdoor performance, maintaining the biodegradable characteristics of these materials.

Aprovechamiento de fibras tejidas de yute como material de refuerzo en biocompuestos de ácido poliláctico//Use of jute woven fibers as reinforcement material in polylactic acid biocomposites

Biotecnia ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 67-73
Author(s):  
Heidy Burrola-Núñez ◽  
Pedro Jesús Herrera-Franco ◽  
Herlinda Soto-Valdez ◽  
Dora Evelia Rodríguez-Félix ◽  
Rodrigo Meléndrez-Amavizca ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Maleic Anhydride ◽  
Polylactic Acid ◽  
Low Cost ◽  
Natural Fibers ◽  
Mechanical And Thermal Properties ◽  
Jute Fibers ◽  
Reinforcement Material ◽  
Reinforcing Material ◽  
And Storage

El aprovechamiento de residuos agroindustriales es una opción que beneficia al medio ambiente. Durante la elaboración de productos con fibras tejidas de yute (FTY) se generan fragmentos, los cuales no tienen un uso específico. En este trabajo, se propone la utilización de residuos de FTY como material de refuerzo en láminas de ácido poliláctico (PLA), como una alternativa ecológica y sustentable de obtener biocompuestos biodegradables a bajo costo que puedan sustituir a los plásticos provenientes del petróleo. Con el objetivo de mejorar la compatibilidad de las FTY y el PLA se utilizaron tratamientos fisicoquímicos en las fibras como la irradiación gamma (IG) y la funcionalización con anhídrido maleico (AM). Los resultados de los biocompuestos de PLA/ FTY (AM) revelaron mejoras en las propiedades mecánicas y térmicas comparadas con el PLA puro; con un incremento en los módulos elástico, de flexión y almacenamiento del 48%, 6% y 23 %, respectivamente. Esto entreabre la posible aplicación de los biocompuestos de PLA/FTY en envases rígidos, así como el camino para el aprovechamiento de otras fibras naturales usadas localmente.ABSTRACTThe use of agroindustry waste is an option that benefits the environment. During the production of products with woven jute fibers (WJF) fragments are generated which do not have a specific use. In this work, we propose the use of WJF residues as a reinforcing material in laminates of polylactic acid (PLA) as an ecological and sustainable alternative to obtain low cost biodegradable biocomposites that can replace petroleum plastics. In order to improve the WJF and PLA compatibility, physicochemical treatments were used in fibers such as gamma irradiation (GI) and functionalization with maleic anhydride (MA). The results of PLA/WJF (MA) biocomposites revealed improvements in the mechanical and thermal properties compared to neat PLA; with an increase in elastic, flexural and storage modules of 48%, 6%, and 23%, respectively. This opens up the possible application of PLA/ WJF biocomposites in rigid containers, as well as the way to take advantage of other natural fibers used locally.

scholarly journals Synthesis and Characterization of Natural Fibers Reinforced Fiber Epoxy Composites

2015 ◽  
Vol 51 ◽  
pp. 47-53
Author(s):  
U. Mahaboob Basha ◽  
D. Mohana Krishnudu ◽  
P. Hussain ◽  
K. Manohar Reddy ◽  
N. Karthikeyan ◽  
...  
Keyword(s):  
Room Temperature ◽  
Natural Fibers ◽  
Epoxy Composites ◽  
Synthesis And Characterization ◽  
Mechanical And Thermal Properties ◽  
Epoxy System ◽  
Pennisetum Typhoides ◽  
The Matrix ◽  
Reinforced Fiber

In the current work epoxy resin is chosen as matrix, treated Sacharum offinarum ( SugarCane) fiber, Pennisetum typhoides (Jowar)/ Fillet miller (Ragi) filler are chosen as reinforcement. Room temperature cured Epoxy System filled with Sacharum offinarum fiber and Pennisetum typhoides (Jowar)/ Fillet miller (Ragi) filler are synthesised by mechanical shear mixer, then kept in a Ultra sonic Sonicator for better dispersion of Pennisetum typhoides (Jowar)/ Fillet miller (Ragi) filler in the matrix. Different weights of modified Pennisetum typhoides (Jowar)/ Fillet miller (Ragi) filler (1,2,3,4,5 gm wt) has been incorporated into the Epoxy matrix in order to study the variation of Mechanical and Thermal properties.

Abiotic Degradation of Oil Asphaltens

2021 ◽  
Vol 627 (5) ◽  
pp. 53-56
Author(s):  
K. V. Shabalin ◽  
◽  
L. E. Foss ◽  
L. I. Musin ◽  
O. A. Nagornova ◽  
...  
Keyword(s):  
Radiation Resistance ◽  
Electron Beams ◽  
Reaction Products ◽  
High Radiation ◽  
Natural Conditions ◽  
Abiotic Degradation ◽  
Hydrophilic Lipophilic Balance ◽  
Intense Electron Beams ◽  
Biotic Degradation ◽  
Intense Electron

This review is devoted to the generalization and systematization of the available literature data on the processes of abiotic degradation of asphaltenes, which can occur in natural conditions. In particular, it was shown that exposure to sunlight, and especially UV radiation, triggers photolysis and photooxidation reactions in asphaltenes, leading to an increase in the oxygen content in them, thereby shifting the hydrophilic-lipophilic balance towards hydrophilicity. At the same time the availability of reaction products for subsequent biotic degradation by microorganisms is increased. Exposure to ionizing radiation does not lead to a significant change in the molecular composition of asphaltenes, due to their high radiation resistance. As exception there is the irradiation of asphaltenes with intense electron beams, which leads to their significant degradation.

scholarly journals Heterogeneity in the Chemical Composition of Biofertilizers, Potential Agronomic Use, and Heavy Metal Contents of Different Agro-Industrial Wastes

2019 ◽  
Vol 11 (7) ◽  
pp. 1995 ◽  
Author(s):  
Sabrina Cajamarca ◽  
Douglas Martins ◽  
Juscimar da Silva ◽  
Mariana Fontenelle ◽  
Ítalo Guedes ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Raw Materials ◽  
Chemical Characterization ◽  
Industrial Wastes ◽  
Chemical Compositions ◽  
Agronomic Efficiency ◽  
Waste Products ◽  
Metal Contents ◽  
Great Heterogeneity

Several agro-industrial, livestock, and food wastes can be recycled to create biofertilizers. This diversity of raw materials can result in nutritional imbalance and an increase in heavy metal content, which could make the final product unfeasible. Thus, the chemical characterization of the raw materials and their influence on the sustainable and safe production of biofertilizers need to be better understood. In this context, the objective of the present study was to evaluate the chemical characteristics of agro-industrial residues used in the manufacture of an aerobic liquid biofertilizer. We analyzed the macronutrient, micronutrient, and trace metal contents of seven waste products used as raw materials to create a biofertilizer. In addition, a survey of secondary biofertilizer data from different residues was carried out that showed great heterogeneity in the chemical compositions of these residues, which has a direct impact on the agronomic efficiency of these biofertilizers. The characterization revealed that some materials may be contaminants of the soil, due to high levels of trace metals, especially cadmium. We conclude that the generation of detailed inventories, such as those of the nutrient and heavy metal contents of the raw materials and biofertilizers produced, is indispensable for the correct recommendation of biologically-based inputs in agriculture.

Preparation and study on the optical, mechanical, and antibacterial properties of polylactic acid/ZnO/TiO2 shared nanocomposites

2020 ◽  
Vol 36 (3) ◽  
pp. 285-311
Author(s):  
Ali Tajdari ◽  
Amir Babaei ◽  
Alireza Goudarzi ◽  
Razie Partovi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Antibacterial Activity ◽  
Optical Properties ◽  
Polylactic Acid ◽  
Field Emission ◽  
Antibacterial Properties ◽  
Hydrolytic Degradation ◽  
Scanning Electron

In this research, first, ZnO nanorods were synthesized by hydrothermal method and characterized in terms of morphological and structural properties by means of field emission scanning electron microscopy, Fourier transform infrared, and X-ray diffraction techniques. Subsequently, polylactic acid/ZnO, polylactic acid/TiO2, and polylactic acid/ZnO/TiO2 nanocomposites with different percentages of nanoparticles and two different types of ZnO morphologies were prepared and their microstructural, optical, mechanical, hydrolytic degradation, and antibacterial properties were investigated. Field emission scanning electron microscopy results of polylactic acid/ZnO and polylactic acid/TiO2 samples showed a proper dispersion and nanoparticle distribution for low percentages (up to 5 wt%) and increased aggregation for the higher percentages. Besides, a large increase in the aggregation tendency was observed for combined nanoparticles (polylactic acid/ZnO/TiO2 nanocomposites). Results of the tensile test, the UV–Vis absorption tests, and the hydrolytic degradation tests of the samples showed an enhanced mechanical (approximately 55% increase in the presence of 3–5 wt% of nanoparticles) and light absorption and degradation (approximately 85% increase in the presence of 3–10 wt% of nanoparticles) for the polylactic acid by incorporating nanoparticles. It was also observed that, in addition to the quality of dispersion and distribution of nanoparticles in the polymeric matrix, the type of morphology of nanoparticles can contribute to the improvement of these properties. The cylindrical morphology of ZnO played a greater role on improving the polylactic acid mechanical properties compared to the spherical ZnO morphology (approximately 20%). On the contrary, the increased polylactic acid optical properties and degradation with ZnO spherical morphology were more pronounced (approximately 60%). Interestingly, when both ZnO and TiO2 were added, a synergistic effect in the case of UV-shielding and degradation rate and alternatively, a detrimental effect on the mechanical properties were detected. (The polylactic acid optical properties increased by about 17% and its degradation more than doubled.) Furthermore, the antibacterial activity of polylactic acid was investigated against the two Gram-positive Listeria monocytogenes and Gram-negative bacteria Escherichia coli by incorporating nanoparticles. The results indicated that as the nanoparticle percentage increases, the antibacterial activity steadily increases.

scholarly journals Performance of lightweight mortar reinforced with doum palm fiber

2020 ◽  
pp. 002199832097519
Author(s):  
Fatma Naiiri ◽  
Allègue Lamis ◽  
Salem Mehdi ◽  
Zitoune Redouane ◽  
Zidi Mondher
Keyword(s):  
Mechanical Properties ◽  
Thermal Properties ◽  
Natural Fiber ◽  
Cement Mortar ◽  
Low Cost ◽  
Natural Fibers ◽  
Construction Materials ◽  
Mechanical And Thermal Properties ◽  
Palm Fiber ◽  
And Control

Natural fibers are increasingly used in composites because of their low cost and good mechanical properties. Cement reinforced with natural fibersis contemplates as a new generation of construction materials with superior mechanical and thermal performance. This study of three sizes’effect of Doum palm fiber explores the mortar’s behavior reinforced with different fiber ratio. The aim is to determine the optimal addition to improve mechanical and thermal properties of natural fiber reinforced cements. Physical, mechanical and thermal properties of composite are examined. Tensile properties of Doum fibers are verified to determine their potential as reinforced material. Findings prove that the use of alkali-treated Doum fiber as reinforcement in cement mortar composite leads to the upgrading of the mechanical properties including thermo-physical properties against composites reinforced with raw fibers and control cement mortars. While, the compression and flexural strength of the cement mortar reinforced with alkali-treated Doum fiber with diameter 0.3 mm (CT3) are metered to be 11.11 MPa, 5.22 MPa, respectively for fiber content 0.5%. Additionally, based on thermo-physical tests, it is assessed that the thermal conductivity and diffusivity decrease for cement mortar reinforced with Doum fiber with diameter 0.2 mm (CT2).

scholarly journals Influence of Incorporation of Natural Fibers on the Physical, Mechanical, and Thermal Properties of Composites LDPE-Al Reinforced with Fique Fibers

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Miguel A. Hidalgo-Salazar ◽  
Mario F. Muñoz ◽  
José H. Mina
Keyword(s):  
Natural Fibers ◽  
Mechanical And Thermal Properties ◽  
Hot Press ◽  
Scanning Calorimetry ◽  
Aluminum Particles ◽  
Direct Function ◽  
Tetra Pak ◽  
Fique Fibers ◽  
The Impact ◽  
Properties Of Composites

This study shows the effect of the incorporation of natural fique fibers in a matrix formed by low-density polyethylene and aluminum (LDPE-Al) obtained in the recycling process of long-life Tetra Pak packaging. The reinforcement content was 10, 20, and 30% fibers, manufactured by hot-press compression molding of composite boards (LDPE-Al/fique). From the thermogravimetric analysis (TGA) it was determined that the proportions of the LDPE-Al were 75 : 25 w/w. Likewise, it was found that the aluminum particles increased the rigidity of the LDPE-Al, reducing the impact strength compared to LDPE recycled from Tetra Pak without aluminum; besides this, the crystallinity in the LDPE-Al increased with the presence of aluminum, which was observed by differential scanning calorimetry (DSC). The maximum strength and Young’s modulus to tensile and flexural properties increased with the incorporation of the fibers, this increase being a direct function of the amount of reinforcement contained in the material. Finally, a reduction in the density of the compound by the generation of voids at the interface between the LDPE-Al and fique fibers was identified, and there was also a greater water absorption due to weak interphase fiber-matrix and the hydrophilic fibers contained in the material.

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