Study on Mechanical Properties of Banana Fiber-Reinforced Materials Poly (Lactic Acid) Composites

Synthetic materials reinforced with natural fibers are attracting great attention of scientists and researchers. Sustainability and eco-friendly nature along with easy availability and low cost are the key reasons. In this work, a natural fiber such as a banana fiber was investigated to create bioavailable materials while enhancing mechanical properties. The banana fiber was extracted from banana sheath by the mechanical method combined with chemical treatment with NaOH 1, 2, 3, 4, and 5%. Treatment of the banana fiber with NaOH effectively removes other impurities from the fiber surface and the fiber surface becomes rough, increasing the compatibility and bonding between banana fiber and PLA. The reported optimum NaOH concentration was 5% banana fiber used for the material polylactic acid (PLA) composite/banana fiber. The composites (BF) were prepared by the hot melt mixing method. The results showed that 20% by weight of banana fiber gave good results and the mechanical strength values kept at the specified level (tensile strength: 52.57 MPa, flexural strength: 70.35 MPa, impact strength: 155.45 J/m and hardness: 23.8 Hv). SEM observations showed visual evidence that surface impurities were removed from the fiber by NaOH treatment.

Biocomposites Developed with Litchi Peel Based on Epoxy Resin: Mechanical Properties and Flame Retardant

Bio-based composites are reinforced polymeric materials, which include one or two bio-based components. Biocomposites have recently attracted great attention for applications ranging from home appliances to the automotive industry. The outstanding advantages are low cost, biodegradability, lightness, availability, and solving environmental problems. In recent days, biodegradable natural fibers are attracting a great deal of interest from researchers to work on and develop a new type of composite material for diverse applications. The objective of this work is to evaluate fire resistance and mechanical properties of epoxy polymer composites reinforced with lychee peel (Vietnam), at 10 wt%, 20 wt%, and 30 wt% mass%. The study showed that the mechanical properties and flame retardancy tended to increase in the presence of lychee peel reinforcement. In the combined ratios, 20 wt% lychee rind gave a limiting oxygen index of 21.5%, with a burning rate of 23.45 mm/min. In terms of mechanical strength, in which the Izod impact strength increased by 26.46%, the compressive strength increased by 25.20% and the tensile strength increased by 20.62%. The microscopic images (SEM images) show that the particle distribution is quite good and the adhesion and wetting compatibility on the two-phase interface of lychee peel-epoxy resin are strong.

Banana Fiber-Reinforced Epoxy Composites: Mechanical Properties and Fire Retardancy

Currently, the growing field of technology has paved the way for using environmental friendly resources; in particular, plant origin holds ecological concern and renewable aspects. Currently, natural fiber composites have widening attention, thanks to their eco-friendly properties. In the present work, the composite material is reinforced with natural fibers from the bark of banana trees (banana fibers), a material available in Vietnam. Banana fibers are extracted from banana peels, pretreated with NaOH 5%, and then cut to an average length of 30 mm. Banana fiber is reinforced for epoxy resin Epikote 240 with mass percents: 10 wt.%, 15 wt.%, 20 wt.%, and 25 wt.%. The results were evaluated through structural morphology (SEM), mechanical properties, fire resistance, and thermal properties. Experimental results show that the tensile, compressive, and impact strengths of biosynthetic materials up to 20% by weight have increased compared to epoxy neat. Flame retardant and thermal properties are kept stable; 20 wt.% banana fiber gives a limiting oxygen index of 20.8% and satisfactory thermal stability.

Hybrid Biocomposites Based on Used Coffee Grounds and Epoxy Resin: Mechanical Properties and Fire Resistance

Studies on using biomaterials hybridized with other materials to produce biomaterials have been paid more attention due to their low cost, abundance, renewability, and degradability. Therefore, these materials are ecofriendly and nontoxic to humans. A large number of used coffee grounds (SCGs) are often discarded and replacements are necessary for dealing with environmental problems. This work developed sustainable materials by reusing SCGs. Used coffee grounds were mixed with epoxy resin at different amounts: 30 wt %, 40 wt %, 50 wt %, and 60 wt %. SCGs were treated with 0.5 N NaOH, at SCGs/NaOH ratio of 1 : 2. SEM images showed that the material with 30 wt % SCGs has good compatibility without phase division on the SCGs-epoxy interface. Results of mechanical properties of epoxy composites with 30 wt % SCGs are as follows: tensile strength of 44.81 ± 10 MPa, flexural strength of 80.07 ± 0.16 MPa, compressive strength of 112.56 ± 0.11 MPa, and Izod strength and impact of 8.21 ± 0.19 kJ/m2. In terms of flame-retardant properties, the oxygen index is limited to 20.8% ± 0.20 and the burning rate according to UL94HB is 27.02 ± 0.29 mm/min. The obtained results indicate that it is possible to produce biohybrid composites from epoxy resin and SCGs. This work offers an ecofriendly alternative method to use the waste of the coffee industry. It contributes to improvements of the general characteristics of composites such as mechanical, thermal, and flame-retardant properties. This work proved that SCGs have a high potential to be used in a wide range of composite materials for civil engineering applications.

Research on Fabrication of Flame Retardant Nanocomposite Coating to Protect Steel Structures on Epikote 240 Epoxy Resin Base with the Synergy of MWCNTs and Fly Ash

The use of industrial wastes such as thermal power plant fly ash can reduce the environmental risk. The fly ash properties are useful and can contribute to organic coatings. This paper examines a new strategy for coatings that protect steel structures from the effects of fire while enhancing mechanical properties. The aim of this study was to show that the fly ash additive can be a partial replacement for other conventional additives while also having a flame retardant effect. To study the effectiveness of the use of fly ash additives, we have sought to combine them with nanoadditives. Specifically, we study the synergy of fly ash with multi-wall carbon nanotube additives to reinforce the coating on the system: epoxy Epikote 240/ammonium polyphosphate (APP)/pentaerythritol (PER), and melamine. Content of fly ash was studied: 10 wt.% with 0.5, 1, and 1.5 wt.% of multi-wall carbon nanotubes (MWCNTs). The results prove that the synergies between fly ash and multi-wall carbon nanotubes increase the fire resistance to increase the protection of steel structures of the building. When using 10 wt.% fly ash and 1 wt.% MWCNTS, the coating can be considered as a flame retardant material with UL 94V-0 fire resistance and the limiting oxygen index of 27.2%..

Study on the Properties of Epoxy Composites Using Fly Ash as an Additive in the Presence of Nanoclay: Mechanical Properties, Flame Retardants, and Dielectric Properties

Small and light fly ash is a by-product of thermal power plants, in which oxides mainly present in fly ash are suitable to reinforce composite materials. Its content accounts for 10, 20, 30, 40, and 50% of those materials. However, due to the smooth surface, it cannot stick completely in plastics. Therefore, in this work, it was studied to combine nanoclay additive (I.30 E) with 1, 3, and 5% by weight to synergize to improve mechanical strength, fire retardation, and electrical properties. Mechanical properties and flame retardant properties have improved markedly. At the combined ratio of 40% by weight of fly ash and 3% nanoclay, nanocomposites have tensile strength values of 64.12 MPa, flexural strength of 89.27 MPa, compressive strength of 215.23 MPa, and impact resistance of Izod 14.45 kJ/m2, oxygen index limited to 26.8% of fire retardant material. In terms of dielectric strength, the electric strength of pure epoxy is 17.5 kV/mm, higher than that before adding nanoclay (12.7 kV/mm). The presence of nanoclays in the material creates a tortuous electric path, slowing the propagation of the power plant, which is the main factor that improves the breaking strength of the nanocomposite.

Study on Synergies of Fly Ash with Multiwall Carbon Nanotubes in Manufacturing Fire Retardant Epoxy Nanocomposite

In this study, fly ash (FA) and multiwalled carbon nanotubes (MWCNTs) were used to make environmentally friendly nanocomposites, which have high fire retardant properties and high mechanical properties. Industrial waste such as fly ash has become a major concern during the treatment of environmental pollution. MWCNTs were used in this experiment to enhance the flame retardant properties and mechanical properties of materials with fly ash additives. MWCNTs content (0.03, 0.04, and 0.05 wt.%) and fly ash content (30, 40, and 50 wt.%) were studied for three different levels. The flame retardancy of the material is significantly improved by the addition of fly ash/MWCNTs at different rates, especially at 0.04 wt. % MWCNTs and 40 wt. % fly ash with LOI at 26.8%. Regarding mechanical properties, tensile strength increases as fly ash/MWCNTs increase, up to a critical point. On the other hand, the compressive strength of composite increases continuously as fly ash/MWCNTs increase. Scanning electron microscopy (SEM) was used to observe the morphology of fly ash and MWCNTs as well as its distribution in the matrix. This will help analyze the influence of the effectiveness of the combination of fly ash and MWCNTs to the flame retardancy and mechanical properties of fly ash/MWCNTs/epoxy nanocomposites.

Mechanical and Flame-Retardant Properties of Nanocomposite Based on Epoxy Resin Combined with Epoxidized Linseed Oil, Which Has the Presence of Nanoclay and MWCNTs

One of the main disadvantages of epoxy resins is brittleness and flammability, which is one of the biggest threats and the reason for limiting advanced applications. In this study, Epikote 240 (EP) epoxy resin was plasticized with epoxidized flaxseed oil (ELO) at different concentrations (EP/ELO ratios 95/5; 90/10; 85/15; 80/20; 75/25). Then, nanoclay additives and MWCNTs are simultaneously dispersed into the EP/ELO blend by using ultrasonic vibration. The dispersion of ELO and nanoclay additives (nanoclay and MWCNTs) in epoxy resin is observed by using the scanning electron microscope in combination with the XRD method. The effect of ELO, nanoadditives on mechanical properties, and flame retardants is assessed by tensile strength, flexural strength, compressive strength, impact resistance, UL 94HB method, and limiting oxygen index. Experimental results have shown that the mixing ratio of 90/10 w/w is the ratio for good compatibility, high mechanical properties, and fire retardation compared with other ratios. When adding MWCNTs as well as nanoclay I.30E to Epikote 240 epoxy, the mechanical strength and fire resistance have changed greatly: tensile strength of 85.45 MPa, flexural strength of 116.32 MPa, compressive strength of 189.25 MPa, impact resistance Izod of 24.37 kJ/m2, and fire resistance reached at V1.