MATERIAL PROPERTIES CHARACTERIZATION OF COIR

VOL. 10, NO 20, NOVEMBER, 2015ISSN 1819-6608ARPN Journal of Engineering and Applied Sciences 2006-2015 Asian Research Publishing Network (ARPN). All rights reserved.www.arpnjournals.comMATERIAL PROPERTIES CHARACTERIZATION OF COIR CARDBOARDAbdul Rahim Bahari1, Mohamad Salmi Mohd Fudzi2, Nurul ‘Uyun Ahmad2 and Haizuan Abd Rahman11Facultyof Mechanical Engineering, Universiti Teknologi MARA, Bukit Besi Campus, Dungun, Terengganu, Malaysiaof Chemical Engineering, Universiti Teknologi MARA, Bukit Besi Campus, Dungun, Terengganu, MalaysiaE-Mail: Material property is an important element to be considered during the design and engineering application ofcardboard to avoid any failure. This study involves the development method for producing the cardboard by using naturalwaste which is a combination of coir fiber and recycled box. Experimental procedures have been conducted to analyze themechanical properties and chemical properties of the cardboard. The two parameters in producing cardboard are timesoaking coir fiber in sodium hydroxide and the ratio mixing between two materials. For mechanical property, the impulsiveexcitation test has been performed by tapping a specimen elastically by using an impactor. This experiment is to obtaindynamic Young’s modulus property of the cardboard based on its fundamental longitudinal resonant frequency ofvibration. In chemical analyzation property, it was performed by using the Fourier transform infrared spectroscopy (FTIR),a technique to obtain an infrared spectrum of absorption, emission, photoconductivity or Raman scattering of a solidspecimen. The experimental results show that a higher ratio of coir fiber and longer time treated with sodium hydroxideproduces higher dynamic Young’ modulus property of cardboard.Keywords: natural waste, coir, soaking time, mechanical properties, chemical properties.INTRODUCTIONCoir is a natural fiber extracted from the husk ofthe coconut and used in products such as floor mats, doormats, brushes and mattresses. Technically, coir is thefibrous material found between the hard, internal shell andthe outer coat of a coconut. To date, relatively littleattention has been given to the use of this coconut wastewhich can create environmental problem if not disposedproperly. The utilization of coir can create economic andenvironmental advantages because the fibers arerenewable, non-abrasive, cheaper, and available inabundance and show less health and safety concern duringhandling and processing. These advantages can be of greatpotential in converting the coir fibers into pulp and paperproducts.Natural waste such as coconut coir fiber can beeasily found in Indonesia and Malaysia. These fibers areconsidered as environment friendly materials owing totheir biodegradability and renewable characteristics. Thisfiber can be found in almost all of the country in Asia. Thecoconut plantation in Malaysia is in a declining trendcompared to other coconut plantation such as in Philippineand Indonesia. In many island economies, it is a majorsource of revenue and is an integral part of the livelihoodof the population. In searching for such new material, astudy has been made where coconut fiber (also known ascoir fiber) is compounded with composite material. Coir isextracted from the tissues surrounding the seed of thecoconut palm (Cocos nucifera). Coir is the natural fiber ofthe coconut husk where it is a thick and coarse but durablefiber. The husk contains 20% to 30% fiber of varyinglength.Elastic properties are fundamental for thecomplete characterization of materials [1] and importantfor design applications. A well-known technique is animpulsive excitation test by analyzing their dynamicresponse which consists of setting a sample by impact [2]into mechanical vibration in vibrational modes at one ormore frequency at which the vibration displacements areat a maximum (resonance). This method results the timedomain and frequency domain of the impulse signal. Thedecay time of the vibration response due to impactexcitation is characterized by its mass, width, thicknessand length of the sample [3]. Dynamic Young’s modulus[4] can be calculated by using Equation. (1):E 0.9465mff2bL3t3T(1)where E is dynamic Young's modulus, m is mass,ff is natural frequency in flexure dimension, b is width, Lis length and t is the thickness of the cardboard.The purpose of this research is to producecardboard which is contained coir fiber and reused boxesand determine the material properties characterization ofthe coir cardboard. The impulse excitation test will beperformed on the sample to measure dynamic Young’smodulus while Fourier transform infrared spectroscopy(FTIR) test to determine chemical properties.9521

VOL. 10, NO 20, NOVEMBER, 2015ISSN 1819-6608ARPN Journal of Engineering and Applied Sciences 2006-2015 Asian Research Publishing Network (ARPN). All rights reserved.www.arpnjournals.comMATERIALS AND METHODSMaterialsCoir fiber is one of the natural wastes used formaking the cardboard and as a raw material besides therecycled box. Coconut belts can be easily found aroundwith a low cost price. The brown husk fiber from maturedcoconut was collected to obtain the fiber which present atthe outer shell of coconut [5]. Coir fiber was grinded byusing a grinder machine to produce smaller size. Sodiumhydroxide (NaOH), coir fiber, recycled boxes and distilledwater were used in this experiment.Preparation for sodium hydroxideFor chemical treatment of the natural waste, 1Lof 1M sodium hydroxide was prepared. About 40 grams ofsodium hydroxide in forms of solid (pellets) wereweighted by using a weighing scale. The amount ofsodium hydroxide required (40W/g) is weighed out asquickly as possible from a fresh bottle of sodiumhydroxide pellets to minimize the exposure to theenvironmental air. Then, distilled water was added into 1Lbeaker together with the sodium hydroxide pellets until thequantity of 1L. The solution was stirred until it dissolvedcompletely.Soaking processThe concentration of sodium hydroxide andsoaking time were the key factor affecting the treatment.The scope of concentration is 1M. The reasons for theimproved mechanical properties were the removal ofimpurities on the fibers during alkali treatment. In general,high concentration of alkali solution and shorter soakingtime provides better impact strength whereas low andmedium concentration of the alkali solution for longershorter time provides improved flexural and tensileproperties respectively [6]. Immediately after the sodiumhydroxide is prepared, the pulverized coconut belt hasbeen inserted in the beaker. A soaking process takes placein a closed beaker to avoid being exposed to the outsideenvironmental air, causing an inaccurate immersion effectby parameter soaking days.Washing fiberAfter completion of soaking, the material iswashed with distilled water to remove any dirt orchemicals stuck on the fiber. A filter was used during thewashing process. Fiber is washed with distilled waterflows to ensure all fiber cleaned properly. Then the fiberwas put into the ‘loyang aluminium’ for the drying processin the oven. This process was carried out to ensure all dirtor water that is still attached to the fiber to be removed.This process does so easily to a belt weighing sessionsduring mixing between the fiber and the box by apredetermined ratio. This is to ensure the formationprocess is done effectively.Preparation of pulpThe next step is to prepare the pulp by mixing thecoir fiber and recycled box. The desired weight of therecycled box and fiber was prepared. The total mixture ofa combination of both raw materials is 60 grams. For thecoir fiber to be soaked in 1 day sodium hydroxide, theratio taken (fiber to box) were 1:3, 1:1 and 3:1. The ratiotaken is still same for the fiber that was to be soaked for 3days and 5 days.Forming cardboardThe mixing was put into the mold to shape of thecardboard. The method used was manually, which need topress the mixing hardly to ensure the products in tightcondition. Next, the cardboard was transferred to thefabric for drying process. The drying process wasperformed under natural sun about 5 hours to make surethe remaining water is removed. The approximatestemperature of the direct heat sun is about 28-35 C.Impulsive excitation testThe experimental set-up consists of rectangularbars of sample 8cm x 2cm (length x width), an impactor,a microphone and a signal pickup system to measure theacoustic signal. The experiment was conducted in a lownoise level room and the procedure is in accordance with[4]. The microphone was located over an antinode pointand closes enough to the test specimen to measure theacoustic waveform. The specimen was impacted by usingan impactor at the center of the sample and the acousticreading was recorded simultaneously. The procedure hasbeen repeated for five times to obtain the average acousticsignal. Fast Fourier Transform (FFT) signal analysis wasperformed to obtain fundamental longitudinal resonantfrequency. This frequency was then used to calculate thedynamic Young’s modulus of the sample from thementioned equation.FTIR analysisThe sample of each cardboard was cut into smallsize of 2cm x 2cm (length x width). The backgroundspectra were collected to subtract from the test spectra toensure the actual sample is analyzed. Then, the samplewas analyzed by fully-computerized FTIR system whichgenerates the absorbance spectra showing the uniquechemical bonds and the molecular structure of the samplematerial. This profile is in the form of an absorptionspectrum which shows peaks representing components inhigher concentration. Absorbance peaks on the spectrumindicate functional groups (e.g. alcohols, ketones, acidchlorides). Different types of bonds, and thus differentfunctional groups, absorb infrared radiation of differentwavelengths. Although the analysis was performed inabsorbance, it can be converted to transmittance, sincethey are simply the inversions of each other. Theanalytical spectrum was then compared with a reference9522