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

Study on properties of tapioca resin polymer

Environmental, global warming, renewability, recyclability, and biodegradability issues have encouraged scientists and engineers to partially substitute petrochemical-based polymers with green polymers such as natural fibre polymer composites. A major drawback in the development of natural fiber polymer composites is the incompatibility between the matrix and fibre processing temperature, given the high temperature of the matrix based on petroleum and the low degradation temperature for natural fibre. The creation of poly lactic acid as a “green matrix” provides an alternative and a solution for the development of natural fiber polymer composites. In this work, the physical, thermal and mechanical properties of PLA tapioca resin biopolymer derived from industrial grade tapioca were reported in order to determine the optimum processing temperature. A drying process, injection moulding and hot press process are involved in sample preparation. A density test, hardness test, thermogravimetric analysis, and differential scanning calorimetry have been conducted. Afterwards, a tensile test was performed with samples at five different injection temperatures of 160°C, 165°C, 170°C, 175°C and 180°C in order to determine the optimum processing temperature. The sample at 165°C shows the highest result of ultimate tensile strength with 14.904 MPa, and 320.564 MPa for the elastic modulus result. As a conclusion, 165°C was finalized as the optimum processing temperature of PLA tapioca resin biopolymer for future application in the research and development of natural fibre reinforced tapioca resin biopolymer composite

Effect of surface modification on mechanical properties of buri palm (corypha utan) fibre composite reinforcement

Natural fibre materials are replacing synthetic fibre materials since they are considered as a low-cost, lightweight, and biodegradability engineering materials with a good specific strength. However, the effects of some process and geometrical parameters (such as fibre type, size, and concentration, and chemical modification) on the strength of the final natural composite product are not well documented. The purpose of the research is to analyse the physical and mechanical properties of single-strand buri palm fibre under different conditions and surface modification. The buri palm fibre was treated using 5 wt.% and 10 wt.% sodium hydroxide (NaOH) with a duration of 1 and 24 h immersion throughout the whole process. For a single-strand test, the samples were carefully extracted from the corresponding woven fibre by hand. While the woven buri palm fibre composite was fabricated by employing 4 and 5-layering sequences in the hand lay�up technique followed by the compression method. The buri palm fibre showed that a higher concentration of NaOH solution and immersion period led to a lower density. The effectiveness of the alkali treatment in the removal of cellulose and hemicellulose from the fibre strands was verified by chemical composition in FTIR investigation. The highest tensile strength of 159.16 MPa was indicated from the result of single-strand treated with 5 wt.% NaOH for 24 h immersion. This treatment was found as the most appropriate treatment and is employed to fabricate both 4-layer and 5-layer stacking sequence composite. The 5-layer treated composite gives the highest tensile strength and flexural strength of 33.51 MPa and 56.72 MPa, respectively. In conclusion, the mechanical properties increased with the addition of each sequence layering treated fibres in the composite. The obtained results indicate that the utilisation of buri palm fibre as a reinforcement in the epoxy composite can be used in the lightweight and moderate load applications, such as the interior parts in the automotive industry

The effect of fibre treatment on water absorption and mechanical properties of buri palm (Corypha utan) fibre reinforced epoxy composites

Over the past century, there has been a dramatic increase in natural fibre composites in which natural fibre has served as reinforcement in polymer. However, the existence of moisture and defects in natural fibres has impacted the mechanical and physical properties of natural fibre polymer composites. The main objective of this study is to fabricate the buri palm fibre reinforced epoxy composite and evaluate the effects of fibre treatment on water absorption and tensile properties. The buri palm fibre were treated by using 5 wt.% NaOH for 24 h and the laminated composite of untreated and treated four-layer and five layer fibres were fabricated via hand lay-up process. The tensile specimens are prepared according to the ASTM D638 standard and the water absorption experiment was conducted by immersing the specimen in distilled water at room temperature until it reached the saturated moisture absorption. The results revealed that the percentage of moisture uptake was reduced to 69% and 95% in treated four-layer and five�layer sequences. It is observed that the thickness swelling of the composite increased with the increase of sequence layering, while the thickness swelling decreased with treated fibre. Alkali treatment affected the properties of buri palm fibre which improved the interfacial bonding between the fibre and epoxy matrix for better tensile properties and reduced water absorption. Finally, morphology examinations were carried out to analyse the fracture behaviour and fibre failure on the tensile test specimen by using microscope analysis

Water absorption behaviour and mechanical performance of pineapple leaf fibre reinforced polylactic acid composites

Fast-growing scientific work is focusing on alternative sources to replace modern synthetic fibre materials due to the adverse effects caused by petroleum-based materials. Natural fibre possesses high potential as a replacement for synthetic fibre and petroleum�based products. These materials are not only greener and environmental-friendly, but also safe for human health. As such, this study investigated the influence of compatibilising agent of maleated anhydride polyethylene (MAPE) on mechanical performance of pineapple leaf fibre (PALF) reinforced polylactic acid (PLA). The raw materials, such as PALF, PLA, and MAPE, were mixed by using a hot roller mixer machine and hot compression moulding at 190ºC. The specimens were then tested for water absorption and flexibility. The specimens were submerged in water for 0, 7, 14, and 21 days. Three types of tests were conducted, namely water absorption, tensile, and flexural assessments. The results of water absorption, tensile, and flexural tests for the untreated PALF composite (UPALF) and treated PLAF composite (TPALF) were recorded and explained. As a conclusion, composite materials based on hydrophilic natural fibre may reduce the tensile and flexural properties of the composite

Synthesis and characterization of PLA-Chitosan-ZnO composite for packaging biofilms

This research was conducted to improve the characteristics of PLA-Chitosan-ZnO composites. Composites are synthesized from the matrix of Poly lactic acid by modifying Chitosan and Zinc oxide (ZnO) fillers. The purpose of this study was to look at the mechanical, thermal and morphological characteristics seen from the composite. Basically, the bond between PLA and CS is very weak, so to increase the strength of the bond by entering ZnO; thus advancing overall quality (mechanical, thermal and water absorption) of composites (PLA / CS / ZnO). The mechanical properties of composites are enhanced by the addition of ZnO NP into the PLA / CS matrix. However, the tensile strength, modulus, and breakout extension increased to 2wt% of ZnO NP loading but decreased when ZnO NP content increased by 3wt%. This is consistent with the dispersion of homogeneous ZnO particles in the PLA matrix. Combining ZnO particles increases PLA thermal stability. Thus, ZnO has been shown to have potential as an amplifier in biocomposite synthesis with better integrity, although other approaches, such as the use of compatibilizers in ZnO surface modification, will be needed to improve PLA properties simultaneously. The results obtained in this work can be used on environmentally friendly films

Characterisation of the woven fabric of jute, ramie and roselle for reinforcement material for polymer composite

The current research aims to describe the natural woven of jute, ramie and roselle as a reinforcement material for the future applications. On the woven jute, ramie and roselle, four (4) forms of mechanical testing were conducted consisting of grab strength, tearing strength, puncture strength, and fibre pull-out testing. Additionally, the unsaturated polyester resin (UPE) was reinforced with all the woven fabric to determine its effect on the properties of the tensile. The test result for jute and ramie is 103.5N and 137.9N from multiple fiber pull-out, so more force is required in the warp direction to pull the fiber out than in the weft direction which is 102.5N and 124.3N. The result of grab test is opposite from multiple fibre pull-out test. Woven fabric in weft direct required more force which is about 1.4-29.2%. Less than 115N needed for splitting ramie in warp and weft direction compared jute and roselle fabric. The different energy provided by rosselle compared to jute and ramie fabric is 1-1.5Nm based on the puncture resistance test. Result of fibre reinforced UPE is obtained are in range of 21.4 - 27.9MPa which analogous to yarn and textile testing

Effect of water absorption behaviour on tensile properties of hybrid jute-roselle woven fibre reinforced polyester composites

Incorporating natural fibre as reinforcement in the polymer matrix has shown a negative effect since the natural fibre is hydrophilic. The natural fibre easily absorbs water which causes an effect on the mechanical properties of the composites. The objective of this paper is to investigate the water absorption behaviour of hybrid jute-roselle woven fibre reinforced unsaturated polyester composite and the effect of water absorption in terms of tensile strength and tensile modulus. The effect of hybrid composite on the thickness swelling will be tested. The fabrication method used in this study is the hand lay-up technique to fabricate 2-layer and 3-layer composites with layering sequences of woven jute (J)/roselle (Ro) fibre. The results of the study showed that pure roselle fibres for 2 and 3-layer composites have the highest water absorption behaviour 3.86% and 5.51%, respectively, in 28 days) as well as thickness swelling effect, whereas hybrid J-Ro and J-J-Ro composites showed the least water absorption (2.65% and 3.76%, respectively) in 28 days) in both the tests. The hybridisation between jute and roselle fibres reduced water absorption behaviour and improved the fibres dimensional stability. The entire composites showed a decreasing trend for both tensile strength and tensile modulus strength after five weeks of water immersion. Jute fibre composite hybridised with roselle fibre can be used to reduce the total reduction of both tensile strength and tensile modulus throughout the whole immersion period. Moreover, the tensile testing showed that jute fibre composite hybridised with roselle fibre have produced the strongest composite with the highest tensile and modulus strength compared to other types of composites. The hybridisation of diverse fibre reinforcements aids in minimising the composite water absorption and thickness swelling, hence reducing the effect of tensile characteristics

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