Tensile Modulus Values Research Articles

The Epoxy-based composites with Size-Fractionated Waste Areca Sheath: An Experimental Investigation on the Macroscopic and Vibrational Properties

The use of Areca sheath in developing a newer composite material is proposed in this article. The Areca sheath particulates are extracted by pulverizing long sheaths into different sizes of particulates and are reinforced into the epoxy to process the composites. The study evaluated these composites' macroscopic and vibrational properties, revealing that those with coarse particulates demonstrated superior tensile and flexural strengths, impact strength, hardness, and natural frequency. Notably, the coarse epoxy composite with a 10% weight fraction of particulates exhibited tensile strength and modulus values of 24 MPa and 1050 MPa, respectively. These findings suggest that incorporating a 10% weight fraction of coarse Areca sheath particulates into epoxy resin significantly enhances the composite's macroscopic and vibrational properties, making it a promising material for various building applications like Partition panels, Ceiling Panels, and similar applications.

Prediction of Tensile Properties of Natural Fiber Reinforced PP Hybrid Composites by Facca-Kortschot-Yan (FKY) and Palsule Equations

Abstract Natural fiber reinforced polymer hybrid composites are advanced materials for commercial and engineering applications. Rule of hybrid mixtures has been applied to develop Facca-Kortschot-Yan (FKY) Equation and Palsule equation for predicting tensile strength and modulus of these hybrid polymer composites. This study predicts the values of tensile strength and modulus of a few natural fibers reinforced polypropylene hybrid composites by these two equations and compares them with the reported experimental values.

Development of hydroxyapatite/poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/gelatin composite nanofibers to improve bone‐forming cell proliferation and mineral deposition

AbstractCalcium phosphate hydroxyapatite (HA) was successfully incorporated into poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/gelatin (PHBV/GEL) nanofibers through an electrospinning process in a hexafluoroisopropanol solvent (HFIP). The PHBV/GEL was electrospun and collected using a rotating metallic network to develop highly ordered nonwoven mats. The effects of HA addition on the morphologies of the obtained fibers were investigated using SEM. The average diameter of the fibers ranged around 700–900 nm, depending on the HA content. From a mechanical perspective, the addition of HA nanoparticles showed variations in tensile strength and elastic modulus values. The lowest tensile strength measured for neat PHBV/GEL was 0.37 ± 0.08 MPa with an elastic modulus of 9.45 ± 0.65 MPa, whereas the highest tensile strength reported for 5% HA‐loaded PHBV/GEL mats was 1.1 ± 0.4 MPa with an elastic modulus of 16.9 ± 0.39 MPa. In addition, cell viability, and mineral deposition were also studied using MC3T3‐E1 pre‐osteoblasts. The in vitro experiment results showed that the HA loaded‐PHBV/GEL mats provide optimal conditions for cell growth and osteogenic differentiation of MC3T3‐E1 cells. This study reveals the potential of PHBV/GEL/HA matrices in the development of novel guided bone‐regeneration (GBR) membranes for orthopedic and craniomaxillofacial surgery, by providing favorable structural features for attachment, growth, and differentiation of osteoblast cells.Highlights Simple and cheap electrospinning strategy toward network‐like fibrous mats. Microstructure, mechanical, and biological features were evaluated. Electrospun PHBV/GEL/HA promoted calcium phosphate deposition by MC3T3‐E1 cells.

Mechanical Characterization of Curaua Fiber/Babool Wood Particle Reinforced Polyester Hybrid Composite

Background: The researchers are in the situation to satisfy the demand for engineering materials by developing novel eco-friendly materials. The natural fiber composites are the substitutes for the synthetic material. Introduction: The mechanical properties of curaua fiber-reinforced polyester (CFRP) composites were investigated, as well as the effects of curaua fibre infusion with Babool Wood particles (BWP). Methods: The composite specimens were fabricated using a hand lay-up approach using varying amounts of curaua fibres (CF) and babool wood particles in a 1:1 ratio in order to test the tensile strength and flexural strength. Results: The results demonstrated that before weakening, the tensile strength and flexural strength of the composite samples rose by up to 40% for hybrid reinforcements. Comparing samples made of pure resin to those made of the composite at 40 weight percent (CF20/BWP20), the tensile and bending strengths of the composite are improved by 93.42% and 86.4%, respectively. Conclusion: The tensile and flexural modulus values of the hybrid composites increased by up to 50% fiber, but less successfully (CF25 and BWP25). The fracture mechanism of the shattered composite samples was examined using scanning electron microscopy.

Biobased polymer nanocomposites prepared by in situ polymerization: comparison between carbon and mineral nanofillers

Two series based on poly(propylene 2,5-furandicarboxylate)-block-poly(tetramethylene oxide) (PPF-b-F-PTMO) containing carbon and mineral nanofillers that differ in shape (1D and 2D) were synthesized via in situ polymerization. The influence of the addition of the 1D-type nanoparticle, i.e., carbon nanofibers (CNFs) and halloysite nanotubes (HNTs), and the so-called 2D-type, i.e., graphene nanoplatelets (GNPs) and organoclay (C20A), on the properties of a biobased block copolymer was analyzed. The dispersion of nanoadditives in the nanocomposites was determined using a scanning electron microscope (SEM). The thermal properties were studied employing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The introduction of nanoparticles increased the crystallinity (Xc) and the mean values of tensile modulus (E) of the bionanocomposites. In turn, one observed that the decrease in the limited viscosity number (LVN) was visible along with incorporating nanoadditives. The synthesized polymer bionanocomposites reveal the mechanical properties of elastomers during mechanical testing. Moreover, the good processability of the obtained materials by injection molding combined with the comprehensive ability to change mechanical and thermal properties of PPF-b-F-PTMO by tailoring the type and content of the nanofillers can indicate their possible applications in packaging, automotive, sports, construction, and many other industries.

Mechanical and water absorption characterization of rice husk and coconut coir reinforced biochar composites

In this study, four distinct composite samples (Samples A, B, C, and D) were fabricated using varying compositions of biochar, rice bran, coconut coir, and epoxy matrix. Sample A, serving as the baseline with 90% epoxy and 10% biochar, exhibited moderate mechanical properties. Sample B, with 80% epoxy and 20% biochar, demonstrated significantly higher tensile and flexural modulus values, indicative of improved stiffness. Sample C, incorporating 10% rice bran alongside 80% epoxy and 10% biochar, displayed reduced mechanical properties compared to Sample B, potentially due to the lower strength of rice bran particles. Sample D, comprising 80% epoxy, 10% biochar, and 5% coconut coir, demonstrated weaker tensile properties but higher flexural modulus, suggesting enhanced resistance to bending forces. Mechanical testing, water absorption analysis, Fourier Transform Infrared (FTIR) spectroscopy, and SEM imaging provided comprehensive insights into the mechanical and chemical characteristics of the composites, underscoring their potential for diverse applications in sustainable materials development.

Carbon fibers from bitumen-derived asphaltenes: Strategies for optimizing melt spinnability and improving mechanical properties

The demand for low-cost carbon fibers with exceptional mechanical properties continues to grow across various industries. Bitumen-derived asphaltenes have emerged as a promising alternative to polyacrylonitrile (PAN), yet asphaltenes are a complex mixture of compounds, and the fundamental understanding of which asphaltenes are melt spinnable is not clearly understood. In this study, we utilized three distinct types of asphaltenes, each exhibiting notably distinct thermal softening temperatures (Ts) and aromaticity. The optimal melt processing conditions of asphaltenes were determined by dynamic rheology tests. Moreover, we introduced a novel strategy to facilitate the melt spinning of non-spinnable samples by preparing 100 % asphaltene blends with a low Ts asphaltene at different weight fractions. By this means, we achieved continuous melt spinning of precursor fibers. After careful selection of the stabilization and carbonization conditions, uniform carbon fibers were obtained from asphaltenes, which had the highest tensile strength (∼570 MPa) and modulus (∼60 GPa) values, comparable to isotropic pitch-based carbon fibers. Further post-processing of the as-spun fiber resulted in a significant increase in tensile properties, ∼1.1 GPa for strength and ∼91 GPa for modulus. Overall, this study identified spinnable asphaltene precursor characteristics and fiber post-processing methods for achieving low-cost, high-quality carbon fibers from asphaltenes.

Valorisation of Agricultural Residue Bio-Mass Date Palm Fibre in Dry-Blended Polycaprolactone (PCL) Bio-Composites for Sustainable Packaging Applications

Abstract Purpose This study experimentally developed and characterised dry-blended Polycaprolactone (PCL)/date palm fibre biodegradable composites for sustainable packaging applications. Date palm fibres are collected from date palm trees as by-products or waste materials. They will be valorised in bio-composite application to promote fibre-based sustainable packaging items over their non-biodegradable synthetic polymer based conventional packaging products. In the dry-blending process, fibre and polymer are mixed with a shear mixer, while, in a melt-blending process, an extruder is used to extrude fibre/polymer blends after applying heating and high shear pressure to melt and mix polymer with fibres. Dry-blending process offers many comparative advantages, such as less equipment, steps, cost, process degradation, energy consumption and hence, lower harmful environmental emissions; while, a proper fibre/polymer mixing is a challenge and it needs to be achieved properly in this process. Therefore, it is important to understand the effects of dry-blending process on manufacturing of PCL/date palm fibre bio-composites for packaging applications, before promoting the dry-blending as a suitable alternative to the melt-blending process. Methods Short chopped fibres were grinded as powders and dry-blended at a ratio of (0 − 10%) (w/w) with PCL polymer using hand and a shear mixer for 30 min, following a compression moulding process to produce bio-composite samples. Tensile, water contact angle, SEM, TGA, DSC and DMA tests and analysis were conducted. The dry-blended PCL/date palm fibre composites’ properties were compared with reported melt-blended samples’ results found in literature. Results Dry-blended samples showed an increase in tensile modulus values (up-to 20%) with fibre inclusion and these values were found close to the melt-blended samples in the literature. Tensile strength and strain values were reduced which could be related to the poor fibre/polymer interface. Fibre addition affected the thermal, thermo-mechanical and crystallisation processes in PCL polymer matrix. Conclusion Dry-blending is capable of producing bio-composites with a very comparable properties to melt-blended counterparts, although a more details study is needed to conduct in future. The results of this study, could be used carefully to design dry-blended PCL/date palm fibre bio-composites for possible packaging applications. The irregular fibre distribution in dry-blended samples could be improved in different ways which should be investigated in future. Graphical Abstract

Study of the effective fraction of areca nut husk fibre composites based on mechanical properties

Areca nut husk fibers have the potential to be used as reinforcement in polymer composites as a substitute for synthetic fibres. In the manufacture of fibre composites, one of the important factors in determining the strength is the matrix to fibre ratio. This study aims to determine the effective ratio or fraction between areca nut husk fibre and orthophthalic polyester resin. Before using areca nut husk fibre, it was chemically treated so that only cellulose remained in the fibre. The areca nut husk fibre was processed into sheets. The composite was manufactured using the hand lay-up technique. Tensile and flexural tests were carried out to determine the mechanical properties. Based on the results of the tests conducted, there are differences in the mechanical properties of the composites. The tensile test results show that the 40% fibre fraction has the highest tensile strength and modulus values. On the other hand, in the flexure tests, the highest tensile strength and modulus values are found in the 30% fibre fraction.

Mechanical and Rheological Evaluation of Polyester-Based Composites Containing Biochar.

The use of biodegradable polymers as matrices in composites gives a wide range of applications, especially in niche areas. The assessment of the effect of the filler content on the change of mechanical properties makes it possible to optimize the composition for specific needs. Biochar was used as a filler in the studied composites with two different biodegradable blends as a matrix. Poly(1,4-butylene adipate-co-1,4-butylene terephthalate)/polylactide/biochar (PBAT/PLA/BC) and polylactide/poly[(R)-3-hydroxybutyrate-co-4-hydroxybutyrate]/biochar (PLA/P(3HB-co-4HB)/BC) composites with 0, 10, 15, 20 and 30 wt% of biochar underwent mechanical tests. The test results revealed a change in the properties of the composites related to the filler content. The results of the tensile test showed that increasing the biochar content increased the tensile modulus values by up to 100% for composites with 30 wt% of biochar, compared to unfilled matrices, and decreased the elongation associated with the breaking of PBAT/PLA and PLA/P(3HB-co-4HB) matrix composites. The elongation values at break of PBAT/PLA and PLA/(3HB-co-4HB) composites with 30 wt% biochar were reduced by 50% and 65%, respectively, compared to the unfilled matrices. PLA/P(3HB-co-4HB) matrix composites, in contrast to PBAT/PLA/BC, showed a decrease in tensile strength with the increases in filler content from 35.6 MPa for unfilled matrix to 27.1 MPa for PLA/P(3HB-co-4HB)/BC30 composites. An increase in filler content increased the brittleness of the composites regardless of the matrix used, as determined under the Charpy impact-test. This phenomenon was observed for all tested PLA/P(3HB-co-4HB) composites, for which the impact strength decreased from 4.47 kJ/m2 for the matrix to 1.61 kJ/m2 for the composite containing 30 wt% biochar. PBAT/PLA-based composites with 10 wt% of biochar showed slightly lower impact strength compared to the unfilled matrix, but composites with 30 wt% biochar showed 30% lower impact strength than PBAT/PLA. The complex viscosity value increased with increased filler content. For all composites tested on both polyester matrices, the viscosity decreased with increasing angular frequency.

Experimental Studies for the Creation of Composite Materials with Increased Static Mechanical Characteristics

The aim of the study was to experimentally verify the enhancement of certain mechanical properties of a composite material consisting of unsaturated polyester matrix reinforced with fiberglass, by incorporating specific proportions of sodium aluminosilicate (SAS) powders and talc as fillers for the fabrication of large wind turbine blades. Samples composed of these materials, with varying combinations of the added components, underwent testing for tensile and bending strength, and experiments were conducted to determine their modulus of elasticity. The findings indicate that the inclusion of SAS in the matrix material resulted in increased values of tensile strength and modulus of elasticity up to certain proportions. Solely adding talc to the matrix material led to a rise in bending strength. Increasing the talc percentage in the matrix material reinforced with 20% fiberglass resulted in decreased tensile strength and elastic modulus of the samples, while incorporating a blend of SAS and talc into the matrix material reinforced with 20% fiberglass significantly boosted the elastic modulus and tensile strength of the samples under tensile conditions.

Fabrication and Analysis of Physico-Mechanical Characteristics of Chemically Treated Bhendi Fiber Reinforced Thermoplastic Composites: Effect of UV Radiation

Unidirectional polypropylene (PP) composites reinforced with bhendi fibers (BFs) were produced after BFs were subjected to UV light at different intensities. Mechanical parameters such as tensile strength, tensile modulus, and impact strength of irradiated BF/PP composites significantly improved compared to non-irradiated counterparts. To enhance their properties, different amounts of 2-hydroxyethyl methacrylate (HEMA) in methanol were applied to the surfaces of irradiated BFs, and UV light was subsequently used to cure them. Tensile strength, tensile modulus, and impact strength values rose by 32%, 20%, and 37%, respectively, after the optimized grafting and mechanical properties. Alkali solutions were applied to BFs for 30 minutes at varying temperatures and concentrations to alter their surfaces. Then, using the same UV light, BFs were photocured after being grafted with an optimal HEMA solution. Of all the composite samples treated with 10% HEMA, the alkali + 10% HEMA-treated composites exhibited superior mechanical performance. SEM studies exhibited that the optimized alkali with 10% HEMA treated composite had better dispersion than the 10% HEMA treated composite. Water absorption was significantly lower in the treated than in the untreated sample. According to weather studies, the treated specimens may have less loss tensile characteristics than the untreated specimens.

Enhancing damage resistance in tubular triaxial hybrid braided composites: Innovative production and tensile modulus prediction with damage analysis

AbstractBraided composite structures, characterized by their inherent brittleness, necessitate precise damage prediction and prevention to ensure structural integrity/reliability. This study introduces an innovative method for enhancing damage resistance in tubular triaxial hybrid braided composites. These composites employ Epoxy resin as the matrix, with polyester serving as the bias yarn, and glass and basalt as the axial yarns, woven at varying braiding angles. Tensile tests reveal a compelling trend: a reduction in the braiding angle correlates with an increase in the failure load, indicative of quasi‐ductile behavior. A model is also derived for predicting tensile elastic modulus, which demonstrates a strong correlation with experimental results. Furthermore, finite element simulations are utilized to analyze damage within the triaxial hybrid braided composite specimens, providing empirical confirmation of progressive damage occurrence. This research offers a promising avenue for designing/manufacturing advanced composite materials with superior damage‐resistance holding immense potential across a spectrum of engineering applications.Highlights The tubular triaxial hybrid braided composites were produced by Epoxy resin as the matrix, with polyester as the bias yarn, and glass and basalt as the axial yarns at different braiding angles. An innovative method was introduced for enhancing damage resistance in tubular triaxial hybrid braided composites. The effect of operating parameters (braiding angle, type of bias yarns, production method) was investigated. Was tried to predict tensile modulus values in tubular triaxial hybrid braided composites by finite element simulation and developed equations. Finite element simulation exhibited excellent performance in the prediction of tensile behavior of structures manufactured by the innovative method.

Static and dynamic mechanical behavior of intra‐hybrid jute/sisal‐reinforced polypropylene composites: Effect of stacking sequence

AbstractIn the current research investigation, jute and sisal intra‐hybrid woven fabric were specifically tailored to maintain jute and sisal in weft and warp directions, respectively. Jute sisal intra‐hybrid composites were prepared with four layers of intra‐hybrid woven fibers using a compression molding technique. Physical, mechanical (static and dynamic), and thermal stability behavior were investigated, and their structure–property relationship has been established. The obtained results showed that jute‐sisal cross‐interplay‐based hybrid composites recorded maximum tensile and flexural modulus values with minimum anisotropy. It can be concluded from the current experimental investigation that weft/warp orientation and stacking sequence play a significant role in defining the mechanical performance and anisotropic nature of woven fiber‐reinforced laminated composites. Also, the anisotropic properties can be minimized by investigating the effect of fiber orientation and hybridization of natural fibers‐based laminated composites.Highlights Woven mats were tailored to orient different fibers in warp and weft directions. The influence of the fiber's orientation and stacking sequence was analyzed. Fiber orientation and hybridization have influenced mechanical performance. The alternative stacking sequence has shown the highest mechanical properties.

Extraction of Lightweight Platanus orientalis L. Fruit's Stem Fiber and Determination of Its Mechanical and Physico-Chemical Properties and Potential of Its Use in Composites.

Natural fibers extracted from plants are preferred as an alternative to synthetic products. The main reasons for this preference are their affordable cost, light weight and good mechanical properties. However, finding new natural raw materials is challenging due to growth limitations in different geographical areas. Platanus orientalis L. (Eastern plane tree) is a tree with abundant fruits that can grow in many regions of the world. The aim of this study was to determine the mechanical (tensile strength, tensile modulus, elongation), physical (density, fiber diameter) and chemical (cellulose, hemicellulose and lignin) properties of Platanus orientalis L. fruit's stem by fiber extraction from the stems of the tree. It was determined that the extracted fiber had good mechanical properties and cellulose content of 42.03%. As a result of thermogravimetric analysis, it was determined that the plane tree fruit's stem fiber had thermal resistance of up to 299 °C. The tensile strength value was 157.76 MPa, the tensile modulus value was 1.39 GPa and the elongation value was 22.01%. It was determined that it is suitable for use in fiber reinforcement in thermoplastic-based composites at temperatures below 299 °C. According to the results obtained by the mechanical, chemical and physical analysis of Platanus orientalis L. fruit's stem fiber (PoLfs), it could be recommended as a suitable alternative as a reinforcing fiber in thermoplastic and thermoset composites.

Comparison of the usage of nut shell, walnut shell, and pistachio shell as a reinforcement particle on the mechanical and wear performance of polypropylene

AbstractIn this study, the usability of nutshell, pistachio, and walnut shell wastes as reinforcement materials in industrial applications and their comparisons with each other was examined. For this purpose, composite samples with a polypropylene (PP) matrix were produced and their mechanical and tribological characterizations were performed. As a result of the tensile tests, both the tensile strength and elastic modulus values of all composite specimens are higher than those of pure PP. On the other hand, the value of elongation at break is lower. The sliding wear resistance increases with increasing reinforcement with walnut and pistachio shell reinforcement, whereas the positive effect becomes negative when the nutshell reinforcement is over 3 wt%. All three types of reinforcement positively affected the scratch resistance. Pistachio shell reinforcement gives the best result. It has been determined that the relative cutting volume value of the samples increases with the reinforcement rate and the wear behavior changes from ductile to brittle. In light of these results, it has been seen that nut, pistachio, and walnut shells could be used as reinforcement materials in industrial applications instead of being waste or fuel.

Influence of flexible segment length on the phase structure and properties of poly(hexamethylene 2,5‐furandicarboxylate)‐block‐biopolytetrahydrofuran copolymers

AbstractTwo series of biobased poly(ether‐ester)s comprised of poly(hexamethylene 2,5‐furandicarboxylate) (PHF) as the rigid segments and biopolytetrahydrofuran (pTHF) with different molecular masses (1000 and 2000 g/mol) as the flexible segments were synthesized employing polycondensation in the molten state. The study mainly focuses on comparing these two series in terms of the length of the flexible segment. The content of pTHF segments in the copolymer chains varied from 25 to 75 wt.%. The molecular structure and composition, phase structure, and thermal and mechanical properties were characterized by nuclear magnetic resonance (1H NMR) and Fourier‐transformed infrared (FTIR) spectroscopies, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and positron annihilation lifetime spectroscopy (PALS). In addition, mechanical performance and thermo‐oxidative and thermal stability have been investigated. Moreover, cyclic tensile properties were studied to evaluate the elastic properties. 1H NMR and FTIR spectroscopies demonstrate that the syntheses were correctly carried out, which made it possible to obtain the desired compositions of the block copolymers with high molecular masses. The decrease in Tm1, Tc1, and XcPHF values was visible, along with the increase in the flexible segment content. Moreover, the characteristic properties measured by PALS and the values of temperatures designated from TGA (inert and oxidizing atmosphere) did not vary between copolymer series PHF‐b‐F‐pTHF1000 and PHF‐b‐F‐pTHF2000. In turn, along with an increase in flexible segment content and the length of the pTHF, the values of tensile modulus, stress at break, and hardness decrease, while the value of elongation at break increases.

Influence of graphene nanoplatelets (GnPs) and titanium dioxide (TiO2) hybrid fillers on the mechanical, thermal, and morphological performance of polypropylene (PP) based hybrid composites

The main objective of the present study was to investigate the influence of graphene nanoplatelets (GnPs), Titanium dioxide (TiO2), and its hybrid filler on the mechanical, thermal, and morphological characteristics of polypropylene (PP) based hybrid composites for structural applications. The PP-based hybrid composites were prepared using a twin-screw extruder for different filler compositions and then molded into tensile specimens with a mini-jet injection molding setup. Tensile, thermal, and morphological analyses were performed to determine the hybrid capability of the PP-based composites. The results showed that the values of tensile modulus and tensile yield strength show significant improvement at about ∼24% and ∼17%, while the values of elongation at break show a slightly decreasing trend for the hybrid composites compared to PP composites. The thermal stability analysis shows that the higher the hybrid filler content, the higher the temperature. Further, the SEM micrographs for the hybrid fillers show good dispersion onto the PP matrix, which may increase the interfacial adhesion between PP and fillers, thus enhancing the mechanical and thermal properties of PP-based hybrid composites.

Assessing sustainability and green chemistry in synthesis of a Vanillin-based vitrimer at scale: Enabling sustainable manufacturing of recyclable carbon fiber composites

Sustainable manufacturing of carbon fibre (CFs) reinforced polymer (CFRP) composites featured technically by low-cost and rapid manufacturing techniques, use of renewable materials, and non-destructive recycling process. By developing an inherently recyclable thermoset, this research bridges between these three components of sustainable manufacturing by focusing on a fast cured vanillin-based Schiff base polyimide network in all-solid state. In this study, a multifunctional vanillin-based monomer was synthesised at scale in water which can be cured using a diamine without requiring any organic solvent. A CFRP was fabricated using this newly developed Schiff base polymer using compression moulding technique, and its mechanical and thermal/fire performance were compared to a CFRP made of a commercially available automotive grade epoxy resin. The resulting Schiff base CFRP composite demonstrated exceptional fire retardancy, complemented by remarkable tensile strength and modulus values of 427 MPa and 45 GPa, respectively. These characteristics meet the criteria for a broad spectrum of high-performance applications. In contrast to conventional CF reclaiming processes, a novel and efficient chemical recycling approach was introduced, enabling the delamination of CF layers containing the Schiff base network without requiring the separation and purification of the polymer matrix. This approach facilitates the low-cost remanufacturing of new CFRP composites with mechanical performance comparable to the original composite. Finally, green chemistry matrices as well as simplified life cycle assessment (LCA)-like approaches, including the EcoScale and GREEN MOTION rates, were employed to evaluate the efficiency and environmental impact of the CFRP manufacturing process.

Thermal and Mechanical Properties of Polymeric Films Based on PLA / PBAT and Corn Starch and Babassu Mesocarp Starch by Flat Extrusion for Packaging

The influence of different amounts (1, 3 and 5%) of commercial corn starch and of babassu mesocarp starch on a (polylactic acid)/poly (butylene co-terephthalate adipate) (PLA/PBAT) based blend obtained by flat extrusion was ascertained. The thermal and mechanical properties were determined and the results obtained are independent of the type of starch employed but are dependent on its concentration, the nucleating effect of the different starches and on the mobility of the polymer chains that make up the blend. Thermogravimetric analysis indicated the presence of two defined stages of mass loss for all films under investigation. Tensile testing shows that films containing starch had similar behavior to that of PLA in the PLA/PBAT blend, presenting high values of tensile strength, elastic modulus and tensile strength and low values of strain at break. The results suggest that babassu mesocarp starch is viable alternatives to the production of packaging films.