Characterisation of cassava biopolymers and the determination of their optimum processing temperatures

This work reports the characterisation of cassava biopolymers. Moreover, the effects of processing temperature on the tensile properties and phase morphology of cassava biopolymers were investigated. Eight diff erent temperatures were selected as processing temperatures in sample preparation of the cassava biopolymers. Variance analysis justifies that 165 and 170°C are the optimum processing temperatures in producing maximum tensile properties. The present study reveals that the range of processing temperatures for cassava biopolymer was relatively lower as compared to the majority of the petroleum-based polymer. However, its low processing temperature makes this biopolymer has enormous potential in the development of fully biodegradable composites

Making Polyurethanes from castor oil with addition of bentonite and chitosan as coating paints on eco-friendly medical device applications

Polyurethane-based vegetable oil coatings have been used in the past few decades considering the use of petrochemical-based raw materials is a non-renewable material. Vegetable oils used such as soybean oil, palm oil, and castor oil. They have lower environmental impacts, easy availability and biodegradation. In this study, polyurethane synthesis was carried out using the prepolymer method using the reaction of TDI with polyols based on castor oil. To provide anti-microbial properties of polyurethane, a composite method of polyurethane with chitosan was carried out. Whereas to provide heat resistance properties in polyurethane bentonite is added to polyurethane. Polyurethane/bentonite/nanocomposite chitosan was analyzed using the Fourier Transform Infrared Spectra (FTIR) to determine the microstructure of chemical compounds, Thermal Gravimetric Analysis (TGA) for viewing polyurethane/bentonite/chitosan heat resistance, and Scanning Electron Microscope (SEM) to see the morphology of polyurethane/bentonite/chitosan. FTIR analysis have shown the formation of hydroxyl groups in the compound epoxide castor oil, the reaction lasts for 2.5 hours at 50 °C as evidenced by the absorption of OH wave numbers which widens at 3500 cm−1, the hydroxy group formed is the hydroxy group on C atoms secondary, and bentonite NH 3450 cm−1, chitosan cluster C = O urethane widened at 1772 cm−1. TGA analysis have pure polyurethane begins to decrease in mass at 246 °C, while polyurethane with the addition of filler decreases mass at 342 °C

Bio-Nanocomposite Polyurethane / Clay / Chitosan Paints that have thermal resistance and antibacterial properties for biomedical applications

The coating material used for the manufacture of polyurethane paints is a coating of hybrid organic-inorganic materials based on palm oil (oleic acid). Polyols are produced from the synthesis of oleic acid by adding organic and inorganic ingredients. Chitosan and bentonite are organic and inorganic elements, which are used to improve thermal capability and antibacterial properties of polyurethane paint produced. Hybrid bentonite-chitosan is then synthesized with polyols and isocyanate is added, namely TDI (Toluene Diisocyanate) to form polyurethane. In the FTIR spectrum of the polyol on O-H bond at Wavelength 3210.25 cm-1, C-H bond at Wavelength 2856.87 cm-1 and C = O bond at Wavelength 1610.86 cm-1, and hybrid bentonitechitosan of FTIR Analysis Chitosan: -OH group at Wavelength 3250 cm-1, N-H at 3545 cm-1, C = O at wavelength 1681 cm-1, C-H group at Wavelength 2810 cm-1. Bentonite: -OH group at Wavelength 3435 cm-1, Si-O group at Wavelength of 1161 cm-1 and Al-O and Si-O groups at Wavelength 820 cm-1. Aliphatic C-H Cluster at 2815 cm-1 Wavelength and 1125 cm-1 Wavelength indicates the presence of a C-O group. While the results of SEM (Scanning Electron Microscope) from polyurethane products and with the addition of hybrid bentonite-chitosan namely polyurethane paints produced mixed with chemicals and the main ingredients are polyols from palm oil (oleic acid) while small white clumps greyish namely hybrid bentonite-chitosan which has been mixed into polyurethane paint. This study produced a hybrid material of benthicchitosan as a filler in the manufacture of polyurethane paint

Experimental investigation on performance of short pineapple leaf fiber reinforced tapioca biopolymer composites

The performance of short pineapple leaf fiber (PALF) reinforced tapioca biopolymer (TBP) composites were investigated, specifically the effect of fiber length and fiber composition on mechanical properties (tensile properties, flexural strength, and impact strength). Composite samples with different fiber lengths (< 0.50 mm, 0.51 mm to 1.00 mm, and 1.01 mm to 2.00 mm) and different fiber compositions (10%, 20%, 30%, and 40%) were prepared through crushing, sieving, internal mixing, compression molding, and machining processes. The combination of PALF and TBP enhanced the mechanical properties of composites with 30% as the optimum fiber content. However, the influence of different fiber lengths up to 2.00 mm provided no significant effect on producing maximum tensile properties. Good interfacial adhesion between PALF and TBP was evident from scanning electron microscopy analysis. Therefore, the combination of PALF and TBP has great potential as a renewable and biodegradable polymer. Moreover, PALF-TBP composites are expected to become alternatives to petroleum-based polymers

Influence of dammar gum application on the mechanical properties of pineapple leaf fiber reinforced tapioca biopolymer composites

The objective of this work is to investigate the influence of the utilization of dammar gum (DG), which is a biodegradable and renewable binder, on the mechanical properties of short pineapple leaf fiber (PALF) reinforced tapioca biopolymer (TBP). Samples with variable DG concentrations (10%, 20%, 30%, and 40% by weight) and a constant 30% PALF composition were created with varying TBP percentages using an internal mixing process and compression molding. The results showed that PALF-TBP with 10% DG had the highest mechanical properties with tensile, flexural, and impact strength of 19.49 MPa, 18.53 MPa and 13.79 KJ/m2, respectively. Scanning electron microscopy (SEM) images prove the enhanced mechanical characteristics. In addition, Fourier transform infrared spectroscopy (FTIR) analysis showed that the DG improves the matrix and PALF interface. The results show that the utilization of DG significantly enhanced the mechanical characteristics of composites. In addition, it is anticipated that it will be able to create PALF-TBP-DG composites as a potential alternative for conventional polymers in various applications, especially in engineering applications such as automotive and packaging industries. Therefore, it is expected to be capable of contributing to sustainable development goals (SDGs)

Enhancement of flexural modulus and strength of epoxy nanocomposites with the inclusion of functionalized GNPs using Tween 80

In this work, epoxy nanocomposite was prepared with the inclusion of unfunctionalized as-received GNPs (ARGNPs) and functionalized GNPs using surfactant Tween 80 (T80GNPs) in the epoxy resin using a mechanical stirrer. ARGNPs were used as it is, while T80GNPs were prepared through the adsorption of surfactant onto GNPs’ surface using a sonication procedure in an ultrasonic bath. Characterization of nanoparticles using SEM shows that ARGNPs indicated a softer image representing a thinner layer of graphene stacks compared to T80GNP which has a tangible solid-looking image resulting from the sedimentation during the process of filtration. Elementally, both ARGNPs and T80GNPs were found to contain carbon, oxygen, and sulfur, as indicated by the EDX spectrum, with the C/O ratio for T80GNPs being 34.7% higher than that for ARGNPs, suggesting the adsorption of Tween 80 molecules on the GNPs after functionalization. FTIR spectroscopy confirms the attachment of Tween 80 molecules on GNPs surface with T80GNPs spectrum indicated higher peak intensity than ARGNPs. Flexural testing demonstrated that the addition of 0.9 wt.% ARGNPs and 0.9 wt.% T80GNPs to the epoxy increased the modulus of the nanocomposites to 72.1% and 82.6%, respectively, relative to neat epoxy. With the same amount of particle content, both nanocomposites showed increased strength, with ARGNPs and T80GNPs exhibiting strengths of 70.5% and 87.8%, respectively, relative to neat epoxy

Influence of Post-Heat Treatment on the Characteristics of FeCrBMnSi Coating on Stainless Steel 304 Substrate Prepared by Twin Wire Arc Spray (TWAS) Method at Various Stand-off Distance

Twin wire arc spray (TWAS) is a type of thermal spray coating technology that has been extensively researched to improve the service life and overcome wear, cavitation and corrosion in pump impellers. This study aims to investigate the effect of post-heat treatment on the properties of FeCrBMnSi coatings fabricated by the Twin Wire Arc Spray (TWAS) method on 304 stainless steel substrates with varying stand-off distances. NiAl and FeCrBMnSi were employed as bond coats and top coats in this study. The substrate material was sandblasted before the coating process to achieve a surface roughness of 75–100 µm. The TAFA 9000 Electrical Wire-Arc Spraying machine's voltage (V), current (A), and compressed air pressure (Bar) were set to 28.4; 150; and 5, respectively. The coating operation was performed at 100, 200, and 300 mm stand-off distances. The specimens were then post-heated for 3 hours at 500°C and 700°C in a Thermolyne F6010 Furnace Chamber. The quality of the coating produced in this study was evaluated using thickness, hardness, wear, bond strength, micrography, and SEM (Scanning Electron Microscope) testing. According to the findings of this study, specimens with a stand-off distance of 100 mm and a post-heat treatment temperature of 700oC produce the best coating qualities when compared to other specimens. This specimen resulted in a percentage of porosity and unmelted material, thickness, hardness, adhesive strength, and total wear rate of 7.1%, 5.53 x 10-1 mm, 1460 HV, 24.86 MPa, and 3.8 x10-4 mm3/s, respectively

Characterization of cassava biopolymers and the determination of their optimum processing temperatures

This work reports the characterisation of cassava biopolymers. Moreover, the effects of processing temperature on the tensile properties and phase morphology of cassava biopolymers were investigated. Eight different temperatures were selected as processing temperatures in sample preparation of the cassava biopolymers. Variance analysis justifies that 165 and 170°C are the optimum processing temperatures in producing maximum tensile properties. The present study reveals that the range of processing temperatures for cassava biopolymer was relatively lower as compared to the majority of the petroleum-based polymer. However, its low processing temperature makes this biopolymer has enormous potential in the development of fully biodegradable composites

A brief review on the utilization of biopolymers in the manufacturing of natural fiber composites

The study briefly reviews the potential of biopolymers such as polylactic acid (PLA) and Polyhydroxyalkanoate (PHA) to become a green matrix in developing entirely biodegradable composites. The suitability of PLA and PHA in the production of entirely biodegradable natural fibre composites is discussed in this paper. The thermal properties investigation reveals that PLA and PHA are compatible with natural fibre for biocomposite fabrication. Furthermore, this study investigates the effect and performance of mechanical properties, predominantly tensile properties of combination between different natural fibres with biopolymers. In Addition, all essential elements affecting the mechanical characteristics of biocomposites are highlighted. Therefore, the current study's findings are expected capable to provide a clear picture of the biopolymer's position in producing biocomposites. It is also expected that the findings from this study will help further improve the performance of natural fibre reinforced biopolymer composites

The effect of hybridisation on mechanical properties and water absorption behaviour of woven jute/ramie reinforced epoxy composites

Recently, the most critical issue related to the use of natural fibre-reinforced polymer composites (NFRPC) is the degradation properties of composites exposed to the environment. NFRPC’s moisture absorption behaviour has adverse effects on the composite’s mechanical properties and dimensional stability. The purpose of this study is to analyse the mechanical properties of epoxy composites reinforced by jute–ramie hybridisation. This study also analysed the effect of stacking sequence hybridisation of the jute–ramie composite on water absorption behaviour. A five-layer different type of stacking sequence of single and hybrid jute–ramie is produced with the hand lay-up method. The results obtained from this study found that the mechanical properties and water absorption behaviour of a single jute fibre are lower compared to a single ramie fibre. The hybrid of jute–ramie has been able to increase the performance of composite compared to pure jute composites. The mechanical properties of the hybrid jute–ramie composite show a reduction effect after exposure to an aqueous environment due to the breakdown of fibre matrix interfacial bonding. However, after 28 days of immersion, all types of the stacking sequence’s mechanical properties are still higher than that of pure epoxy resin. In conclusion, the appropriate sequence of stacking and selecting the material used are two factors that predominantly affect the mechanical properties and water absorption behaviour. The hybrid composites with the desired and preferable properties can be manufactured using a hand-lay-up technique and used in the various industrial applications