The Effects of Ukam Plant Fiber Variation on the Properties of Polyester Matrix

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

The Effects of Ukam (Cochlospermum Planchonii) Plant Fiber Variation on the Properties of Polyester Matrix Fiber Reinforced Composite Ihom, A.P.1, a, Dennis .O. Onah1 1

Department of Mechanical Engineering, University of Uyo, Uyo, PMB 1017 Uyo-Nigeria

a

ihomaondona@gmail.com, draondonaphilip@gmail.com DOI 10.13140/RG.2.2.35903.92320

Keywords: Cochlospermum planchonii fiber, polyester, composite; matrix, reinforcement, properties.

ABSTRACT. Cochlospermum Planchonii) Plant Fiber Variation on the Properties of Polyester Matrix Fiber Reinforced Composite has been undertaken. The work delved into the production of the composites, this was accomplished by the separate activities of fiber production, mould production and matrix preparation. The fiber was from cochlospermum planchonii (Ukam) plant and the matrix was from polyester. Samples of the produced composites were used in preparing standard test specimens, which were subjected to various tests in order to characterize the composite. In all the properties tested, it was observed that Ukam fiber content had a major role in determining the properties of the composite. The variation of the fiber weight fraction affected all the tested properties of the composite. The results showed that to produce a polyester composite with optimized properties using Ukam fiber, which is biodegradable, the fiber content should be 40%.

Introduction. There are very many situations in engineering where no single material will be suitable to meet a particular design requirement. However, two materials in combination may possess a feasible solution to the materials selection problem. The principle of composite materials is not new.

The use of straw in the manufacture of dried mud bricks, and the use of hair and other bers date back to ancient civilizations [1]. A typical composite material is a system of materials comprising of two or more materials mixed and bonded together. For example, concrete is made up of cement, sand, stones and water. If the composition occurs on a microscopic scale (molecular level), the new material is called an alloy for metals or a polymer for plastics [15]. Types of composites are fiber reinforced composites, metal matrix composites, polymer matrix composites, and ceramic matrix composites [16].

Generally, a composite material is composed of reinforcements. These reinforcements are generally classified into two; synthetic and natural. Synthetic reinforcements include glass, carbon and aramid fibers. Mass production of glass strands was discovered in 1932 when Games Slayter, a researcher at Owens-Illinois accidentally directed a jet of compressed air at a stream of molten glass and produced fibers [16].

Nowadays, natural fibers are an interesting option for the most widely applied fibers in the composite technology. Examples of Natural fibers are jute, hemp, flax, kenaf, coconut, Ukam, sisal, and banana, pineapple fibers from the leaf; cotton and kapok from seed; coir and coconut from the fruit; oil palm and bamboo fibers. The components of natural fibers are cellulose, hemicellulose, lignin, pectin, waxes and water soluble substances. The cellulose, hemicellulose and lignin are the basic components of natural fibers, governing the physical properties of the fibers. In order to fully utilize the natural fibers, understanding their physical and mechanical properties is vital. A unique characteristic of natural fibers reinforced plastic is dependent on the variations in the characteristics and amount of these components, as well as difference in its cellular structure. Therefore, to use natural fibers to its best advantages and most effectively in automotive and industrial application, physical and mechanical properties of natural fibers composite must be considered [2, 3, 4, 5].

MMSE Journal. Open Access www.mmse.xyz

46

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Fibers are made to exist in many forms such as; chopped strand mat, chopped strands, woven roving, surface tissues and continuous strand mat. The matrix holds the reinforcements to form the desired shape of a composite. In the case of polymer based composites, matrix materials are resins. A suitable in 1936 by du Pont [6]. The matrix binds the bres together, protect them against damages and transmit load from bre to fiber. Examples of Matrix materials are Polyester, Epoxy, Vinyl ester, etc.

-chain polymers chemically composed of at least 85% by weight of an ester, a dihydric alcohol and a terephthalic acid. It is a category of polymers that contain the ester functional group in their main chain. Polyester also refers to the various polymers in which [1, 16, 7, 8 9].

The fabrication and properties of composites are strongly influenced by the proportions and properties of the matrix and the reinforcement. The impact strength of fiber reinforced composite increases as the bre volume fraction increases [23]. The strength also improves with increase in bre volume fractions, bre treatment, bre length, bre orientation and the addition of additives [10, 11, 13].

Rasheed et al [20] found that the tensile strength of the composite increases with the fiber volume fraction up to 40% and after which it decreases slightly. Experimental analysis of coir-fiber reinforced polymer composite materials have shown that the mechanical properties of the composite are dependent on the content or the volume fraction of fibers [14]. Based on the experiments, it was found particular value of fiber content. It was also seen that the failure strain increases with the increase in the fiber content. The fiber length is another parameter affecting the mechanical properties of the composite. The fiber length also has an impact on the tensile property, flexural property and impact strength of the composite. Homogeneity is an important characteristic that determines the extent to which a representative volume of the material may differ in physical and mechanical properties from the average properties of the material. The amount of reinforcement that can be incorporated in a given matrix is limited by a number of factors. For example with particulate reinforced metals the reinforcement content is usually kept to less than 40 vol. % (0.4 volume fraction) because of processing difficulties and increasing brittleness at higher contents. On the other hand, the processing methods for fiber reinforced polymers are capable of producing composites with a high proportion of fibers, and the upper limit of about 70 vol. % (0.7 volume fraction) is set by the need to avoid fiberfiber contact which results in fiber damage [12, 16, 17, 18, 19, 21, 22].

Cochlospermum Planchonii known locally as Ukam plants grow in savannah and forest savannah mosaic in West Africa. The plant is a perennial plant with a woody subterranean rootstock, from which, in the rainy season, annual leafy shoots growing around 2 metres tall are produced. The height of the plant depends on the particular habitat and the age. The people of the area where these plants are found use their fibers as sponge and also to reinforce clay with which they produced intricate earthen pots and silos [2, 3, 4, 5]. The objective of this research work is to investigate the effect of Ukam fiber variation on the properties of the composites produced using the fibers.

Materials and Method.

Materials.

The materials used for this work were: polyester resin, Ukam fiber (Cochlospermum Planchonii fibers), sodium hydroxide, acetic acid, releasing agent, methyl ethyl ketone peroxide, calcium carbonate, cobalt naphthenate and water.

Equipment.

The equipment used for the study were as follows: rule, digital weighing balace, Moulds, Tensile Strength Tester, Scanning Electron Microscope, Universal Testing Machine, Flexural Testing Machine, Compression Testing Machine, Rockwell B scale, and Impact Testing Machine MMSE Journal. Open Access www.mmse.xyz

47

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Method.

The work commenced with the production of the composite using polyester as the matrix and cochlospermum planchonii as the fibers. Cut stems of the plants were soaked inside flowing water for thirty days. This enhanced the decay and removal of the thin back of the plant leaving behind, white fibrous stems (see Plate I). The fibers were removed from the fibrous stems with hands (see Plate II). The density, tensile strength, SEM analysis, and water absorption characteristics of the produced fibers were all determined. The produced fibers were then used in the development of polyester composite using various weight fractions of the fiber which were randomly oriented in the matrix (see table 1). The produced composites were allowed to cure for 24 hours before the commencement of their processing into standard test specimens which were used for characterization of the produced composites. Plates III-VIII show some equipment, the developed composites, and some specimens which were used for the characterization of the produced composites.

Plate I: Cut Stems of Cochlospermum Planchonii Fibers

Plate II: Treated and Dried Cochlospermum Planchonii Fibers

Plate III: Scanning Electron Microscope

Plate IV: Developed Samples of Cochlospermum Planchonii Reinforced Polyester Composites

Plate V: Test Specimens of Cochlospermum Plate VI: Universal Strength Testing Machine Planconii Reinforced Composite for tensile test (Testometric)

MMSE Journal. Open Access www.mmse.xyz

48

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Plate VII: Test Specimen of Cochlospermum Plate VIII: Flexural Test Machine Planconii Fiber Reinforced Polyester Composite for Flexural Test

Results and Discussion.

Results.

The results of the work are as presented in Fig.s 1-10 and Plates IX-X

Fig. 1. Ultimate tensile strength variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 2. Extension variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

MMSE Journal. Open Access www.mmse.xyz

49

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Fig. 3. Flexural strength variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 4. Deflection variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 5. Compressive strength variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

MMSE Journal. Open Access www.mmse.xyz

50

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Fig. 6. Maximum load variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 7. Hardness in HRB of the composites with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 8. Toughness variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

MMSE Journal. Open Access www.mmse.xyz

51

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Fig. 9. Density variation with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Fig. 10. Water absorption capacity with % reinforcement of cochlospermum planchonii (Ukam) fiber in polyester composites.

Plate IX: Scanning electron micrograph of 30% fiber content, the clusters in the plate show how the fibers were arranged.

MMSE Journal. Open Access www.mmse.xyz

52

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

Plate X: Scanning electron micrograph of 40% fiber content. The arrangement of the fibers in the polyester show higher volume of fiber than in 30% fiber content above.

Discussion.

Figs. 1-6 show the variation of ultimate tensile strength, extension, flexural strength, deflection, compressive strength, and maximum load properties with % reinforcement of cochlospermum planchonii (Ukam) fibers in polyester ccomposites. All the properties of the developed composites show a steady increase as the Ukam fiber content was increased. This is depicted by the curve which rises steadily, peaking at 40% Ukam fiber content and then falling gradually after 40% Ukam fiber content. All the six properties of the composite are optimized at 40% reinforcement in the polyester composite.

Figs. 7-10 show the variation of hardness, toughness, density, and water absorption capacity properties with % reinforcement of cochlospermum planchonii (Ukam) fibers in polyester composite.

The plot of the hardness against % reinforcement in polyester show the hardness of the composite decreasing as the fiber reinforcement was increased. The hardness property has an inverse relationship with % fiber reinforcement and this is depicted by the curve which falls gradually from left to right. Fig. 8 shows that the toughness of the composites has a direct proportion relationship with % Ukam fiber content. As the fiber content was increased, the toughness property kept increasing up to 40% fiber content, not much significant increase was noticed after 40% fiber content. The same trend is seen in fig. 9. The only difference is that significant reduction in the density property after 40% fiber content can be sighted after 52% Ukam fiber content down. Fig. 10 shows that water absorption capacity property has a direct proportionality relationship with % fiber content. As the fiber content is increasing, so is the water absorption capacity increasing. This is depicted by the continuous rising of the curve from left to right.

Too much water in the composite has degrading effects on the composite which includes swelling and weakening of the strength property. This may call for the selection of an optimum fiber content which will optimize other properties and minimize the amount of Ukam fiber in the composite and from the above results 40% fiber content is the best. The result of the work has shown that the variation of Ukam fiber content in polyester has a major influence on the tested properties of the composite. This is in agreement with previous work by several authors [20, 23, 10, 11, 13].

Matthews and Rawlings [12] argued that the fabrication and properties of composites are strongly influenced by the proportions and properties of the matrix and the reinforcement. Other properties which may significantly affect the properties of a composite are the shape, size, orientation, and distribution of the reinforcement and various features of the matrix such as grain size for polycrystalline matrices. These, together with volume fraction, constitute what is called the microstructure of the composite. It should be noted that even for properties which are microstructure dependent, and which do not obey the law of mixtures, the volume fraction still plays a major role in MMSE Journal. Open Access www.mmse.xyz

53

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

determining properties. The volume fraction is generally regarded as the single most important parameter influencing the composite properties. Also, it is an easily controllable manufacturing variable by which the properties of a composite may be altered to set the application [20, 23, 10, 11].

Plates xi-xii show the Scanning Electron Microscope (SEM) micrograph of the produced polyester composite with 30% and 40% Ukam fiber content. Looking at the two plates it can be seen that the plate with 40% Ukam fiber has more fiber content than the one with 30% fiber content and the distribution is more uniform in the plate with 40% fiber content. Homogeneity in the distribution of the fibers in composite promotes uniform properties. According to these researchers [12, 16, 17, 18, 19, 21, 22], Homogeneity is an important characteristic that determines the extent to which a representative volume of the material may differ in physical and mechanical properties from the average properties of the material. Non- uniformity of the system should be avoided as much as possible because it reduces those properties that are governed by the weakest part of the composite.

The plate also shows the orientation of the fibers. The orientation of the reinforcement within the matrix affects the isotropy of the system [12, 16]. The microstructure as earlier mentioned contributes to the overall properties of the composite.

Summary.

f Ukam (Cochlospermum Planchonii) Plant Fiber Variation

following conclusions drawn from the work: 1. A set of polyester composites were produced by varying the reinforcement with cochlospermum planchonii (Ukam) fiber which is a natural fiber and biodegradable. This makes it environmentally friendly.

2. The work has succeeded in proving that Ukam fiber content in polyester plays a major role in determining the properties of the developed polyester composite reinforced with Ukam fibers.

3. The work has established that using Ukam fiber to produce polyester composite, the amount of Ukam fiber to use in order to optimize the properties of the produced composite is 40% fiber, i.e. a volume fraction of 60 vol.% matrix (polyester) 40 vol.% reinforcement (Ukam fiber) References [1] John, 1972. Introduction to Engineering materials. London: Max Pub., pp 234-250.

[2] Balarami, R. (2013). Mechanical performance of green coconut fiber/HDPE Composites. Int. Journal of Engineering Research and Applications 3: 1262-1270.

[3] Bascom, W.D. (1987). Fiber sizing. Engineered Materials Handbook Metals Park, OH: American Society of Metals, pp 34 35.

Volume 1: Composites.

[4] Benjamin, C. and Tobias (1990) Fabrication and Performance of Natural Fiber-Reinforced Composite Material. 35th International SAMPLE Symposium and Exhibition, Anaheim, pp. 970978.

[5] Burkill, H.M., (1985). The useful plants of West Tropical Africa. United Kingdom: Families A D. Royal Botanic Gardens, Kew Richmond, 2nd Edition, Vol. 1, pp. 960.

[6] Ferguson, A.: In Onah, D.O. (2016) Development and Characterisation of Cochlospermum Planchonii, Fiber Reinforced Polyester Composite, M.Eng Degree Dissertation submitted to the Department of Mechanical and Aerospace Engineering, University of Uyo, Uyo- Nigeria [7] Giuseppe, C., Alberta, G. Latteri, and Gianluca, C. (2011). Composites Based on Natural Fiber Fabrics, Woven Fabric Engineering, Polona Donik Dubrovski (Ed.), ISBN:978-953-307-194-7, pp.

317 342 [8] Hull, D and Clyne, T.W. (1996) An Introduction to Composite Materials (2nd edition)Cambridge: University Press, p 65.

MMSE Journal. Open Access www.mmse.xyz

54

Mechanics, Materials Science & Engineering, September 2016

ISSN 2412-5954

[9] Irawan, A.P., Soemardi, T.P., Widjajalaksmi, K and Reksoprodjo, A.H.S. (2011) Tensile and flexural strength of ramie fiber reinforced epoxy composites for socket prosthesis application.

International Journal of Mechanical and Materials Engineering, Vol. 6 (1): 46-50.

[10] Ku, H., Wang, H., Pattarachaiyakoop, N. and Trada, M. (2009) A review on the tensile properties of natural fiber reinforced polymer composites. Journal of Reinforced Plastics and Composites 28:1169-1189.

[11] Kumar, D. (2014) Mechanical characterization of treated bamboo natural fiber composite.

International Journal of Advanced Mechanical Engineering. Vol. 4( 5):551-556.

[12] Matthews, F.L. and Rawlings, R. D. (2005) Composite Materials: Engineering and Science, 5th Edition London: WoodHead Publishing Limited, pp 1- 300.

[13] Munikenche, T. G., Naidu, A.C.B., Rajput, C. (1999). Some mechanical properties of untreated jute fabric-reinforced polyester composites. Science Direct Journals 30:227 -284.

[14] Naveen, P. N. E. and Yasaswi, M. (2013) Experimental analysis of coir-fiber reinforced polymer composite materials. International Journal Of Mechanical Engineering & Robotics Research, 2( 1): 10-18.

[15] Nick, I. and Mark, J. (2004). Low environ-mental impact polymers. Int. Automotive Research Center, University of Warwick, Vol. 2, No. 30, pp. 99-108.

[16] Onah, D.O. (2016) Development and Characterisation of Cochlospermum Planchonii Fiber Reinforced Polyester Composite, M.Eng Degree Dissertation submitted to the Department of Mechanical and Aerospace Engineering, University of Uyo, Uyo- Nigeria.

[17] Onuegbu, T.U., Umoh, E.T. and Okoroh, N.C. (2013) Tensile behaviour and hardness of coconut fiber-ortho unsaturated polyester composites. Global Journal of Science Frontier Research Chemistry, Vol.13( 1): 1.

[18] Olusegun, D. S., Agbo, S. and Adekanye, T.A. (2012) Assessing mechanical properties of natural fiber reinforced composites for engineering application. Journal of Minerals and Materials Characterization and Engineering 11: 780-784.

[19] Osman, E., Vakhguelt, A., Sbarski, I. and Mutasher, S. (2012) Water absorption behavior and its effect on the mechanical properties of kenaf natural fiber unsaturated polyester composites. 18th International Conference on Composite Materials International Conference on Composite Materials.

2pp.

[20] Rasheed, H. M. M.A., Islam, M. A. and Rizvi, F. B. (2006) Effects of process parameters on tensile strength of jute fiber reinforced thermoplastic composites. Journal of Naval Architecture and Marine Engineering ( 3) 1: 105 117.

[21] Senthiil, P.V. and Sirshti, A. (2014) Studies on Material and Mechanical Properties of Natural Fiber Reinforced Composites. The International Journal of Engineering and Science. Volume 3, pp 18-27.

[22] Tuttle, M. (2004) Introduction. In: Structural analysis of Polymeric Composite Materials University of Washington, USA, ISBN 0-8247-4717-8, pp. 1-40.

[23] Ugoamadi, C.C. (2011) factors that improve the impact responses of Ukam plant fiber reinforced composite. Nigerian Journal of Technology, Vol. 30( 3) : 111-117.

Cite the paper Ihom A.P. & Dennis O. Onah. (2016). The Effects of Ukam (Cochlospermum Planchonii) Plant Fiber Variation on the Properties of Polyester Matrix Fiber Reinforced Composite. Mechanics, Materials Science & EngineeringVol.6, doi: 10.13140/RG.2.2.35903.923202 MMSE Journal. Open Access www.mmse.xyz

55