Effect of Alkali Treatment on Mechanical and Morphological Properties of Pineapple Leaf Fibre/Polyester Composites

  • K. Senthilkumar
  • N. Rajini
  • N. Saba
  • M. Chandrasekar
  • M. JawaidEmail author
  • Suchart Siengchin
Original paper


In this study, our aim is to analyze the influence of fibre treatments and different fibre loading on mechanical, physical and chemical properties of pineapple leaf fibre reinforced polyester composites (PALF/PE). Fibre treatments were carried out with 1 N NaOH and KOH for 1 h. The untreated and treated PALF/PE composites were fabricated with 25 wt%, 35 wt% and 45 wt% fibre loadings by compression molding technique. Fourier Transform Infrared Spectroscopy (FTIR) was used to understand the effects of chemical treatment on PALF mechanical test results revealed that 45 wt% of PALF/PE composites treated with NaOH showed a 35% increase in tensile strength compared to untreated PALF/PE composites. The tensile modulus and the flexural module are also the highest at 45 wt% of KOH treated composites. The highest impact strength of 70 J/m was obtained for PALF/PE composites with NaOH treated fibres at 25% fibre loading. The results show that the fibre treatments in terms of the flexural and inter-laminar shear strength of composites were not effective. SEM of the tensile fractured specimen of PALF/PE composites revealed the changes in fibre characteristics due to the alkali treatment and less fibre pull-out at higher fibre loading. Overall we conclude that 1 N NaOH, 45 wt% treated PALF/PE composites satisfactorily and effectively improved both the mechanical and morphological properties. Obtained composites would be promising for construction materials, furniture and automotive components due to their superior strength and modulus at higher fibre loading.


Pineapple leaf fibre Polyester composites Alkali treatment Mechanical properties Morphological properties Inter-laminar shear strength 



The authors extend their gratitude to the “Kalasalingam Academy of Research and Education, Tamilnadu, India and Institute of Tropical Forestry and Forest Products (INTROP), Universiti Putra Malaysia” for their collaborations and financial support from HiCOE Grant No. 6963108. This research was partly supported by the King Mongkut’s University of Technology North Bangkok through the Post-Doc Program (Grant No. KMUTNB-61-Post-003 and KMUTNB-62-KNOW-13).


  1. 1.
    Sikdar S, Ostachowicz W (2019) Nondestructive analysis of core-junction and joint-debond effects in advanced composite structure. Polym Test 73:31–38. CrossRefGoogle Scholar
  2. 2.
    Sikdar S, Ostachowicz W (2018) Ultrasonic lamb wave-based debonding monitoring of advanced honeycomb sandwich composite structures. Strain 1–15. Google Scholar
  3. 3.
    Rokbi M, Osmani H, Imad A, Benseddiq N (2011) Effect of chemical treatment on flexure properties of natural fiber-reinforced polyester composite. Procedia Eng 10:2092–2097. CrossRefGoogle Scholar
  4. 4.
    Annie Paul S, Boudenne A, Ibos L et al (2008) Effect of fiber loading and chemical treatments on thermophysical properties of banana fiber/polypropylene commingled composite materials. Compos Part A Appl Sci Manuf 39:1582–1588. CrossRefGoogle Scholar
  5. 5.
    Lee S-Y, Chun S-J, Doh G-H et al (2009) Influence of chemical modification and filler loading on fundamental properties of bamboo fibers reinforced polypropylene composites. J Compos Mater 43:1639–1657. CrossRefGoogle Scholar
  6. 6.
    Senthilkumar K, Saba N, Rajini N et al (2018) Mechanical properties evaluation of sisal fibre reinforced polymer composites: a review. Constr Build Mater 174:713–729. CrossRefGoogle Scholar
  7. 7.
    Santosha PVCRK, Gowda ASSS, Manikanth V (2018) Effect of fiber loading on thermal properties of banana and pineapple leaf fiber reinforced polyester composites. Mater Today Proc 5:5631–5635CrossRefGoogle Scholar
  8. 8.
    Chandrasekar M, Ishak MR, Sapuan SM et al (2017) A review on the characterisation of natural fibres and their composites after alkali treatment and water absorption. Plast Rubber Compos. Google Scholar
  9. 9.
    Indra Reddy M, Anil Kumar M, Rama Bhadri Raju C (2018) Tensile and flexural properties of jute, pineapple leaf and glass fiber reinforced polymer matrix hybrid composites. In: Materials today: proceedings 5:458–462.
  10. 10.
    Shahroze RM, Ishak MR, Sapuan M et al (2018) Effect of organo-modified nanoclay on the mechanical properties of sugar palm fiber-reinforced polyester composites. BioResources 13:7430–7444. CrossRefGoogle Scholar
  11. 11.
    Glória GO, Teles MCA, Lopes FPD et al (2017) Tensile strength of polyester composites reinforced with PALF. J Mater Res Technol. Google Scholar
  12. 12.
    Pavithran C, Mukherjee PS, Brahmakumar M, Damodaran AD (1987) Impact properties of natural fibre composites. J Mater Sci Lett 6:882–884. CrossRefGoogle Scholar
  13. 13.
    George J, Bhagawan SS, Thomas S (1996) Thermogravimetric and dynamic mechanical thermal analysis of pineapple fibre reinforced polyethylene composites. J Therm Anal 47:1121–1140. CrossRefGoogle Scholar
  14. 14.
    Vinod B, Sudev LJ (2013) Effect of fiber length on the tensile properties of PALF reinforced bisphenol composites. Int J Eng Bus Enterp Appl 2:158–162Google Scholar
  15. 15.
    Mohd Salit S, Abdan K (2010) Selected properties of hand-laid and compression molded pineapple leaf fiber (PALF)-reinforced vinyl ester composites. Int J Mech Mater Eng 5:68–73Google Scholar
  16. 16.
    Gloria GO, Altoé GR, Moraes YM et al (2015) Tensile properties of epoxy composites reinforced with continuous PALF fibers. In: Characterization of minerals, metals, and materials. Springer, Berlin, pp 139–144.
  17. 17.
    Glória GO, Teles MCA, Neves ACC et al (2017) Bending test in epoxy composites reinforced with continuous and aligned PALF fibers. J Mater Res Technol 6:411–416. CrossRefGoogle Scholar
  18. 18.
    Lopattananon N, Payae Y, Seadan M (2008) Influence of fiber modification on interfacial adhesion and mechanical properties of pineapple leaf fiber-epoxy composites. J Appl Polym Sci 110:433–443CrossRefGoogle Scholar
  19. 19.
    Ray D, Sarkar BK, Rana AK, Bose NR (2001) Effect of alkali treated jute fibres on composite properties. Bull Mater Sci 24:129–135CrossRefGoogle Scholar
  20. 20.
    Mishra S, Misra M, Tripathy SS et al (2001) Graft copolymerization of acrylonitrile on chemically modified sisal fibers. Macromol Mater Eng 286:107–113CrossRefGoogle Scholar
  21. 21.
    Joseph K, Thomast S (1996) Effect of chemical treatment on the tensile properties of short sisal fibre-reinforced polyethylene composites. Polymer 37:5139–5149. CrossRefGoogle Scholar
  22. 22.
    Sreekumar P, Thomas SP, Saiter JM et al (2009) Effect of fiber surface modification on the mechanical and water absorption characteristics of sisal/polyester composites fabricated by resin transfer molding. Compos Part A Appl Sci Manuf 40:1777–1784. CrossRefGoogle Scholar
  23. 23.
    Haque R, Saxena M, Shit SC, Asokan P (2015) Fibre-matrix adhesion and properties evaluation of sisal polymer composite. Fibers Polym 16:146–152CrossRefGoogle Scholar
  24. 24.
    Manalo AC, Wani E, Zukarnain NA et al (2015) Effects of alkali treatment and elevated temperature on the mechanical properties of bamboo fibre-polyester composites. Compos Part B Eng 80:73–83. CrossRefGoogle Scholar
  25. 25.
    Rajesh G, Siripurapu G, Lella A (2018) Evaluating tensile properties of successive alkali treated continuous pineapple leaf fiber reinforced polyester composites. Mater Today Proc 5:13146–13151CrossRefGoogle Scholar
  26. 26.
    Prasad GLE, Gowda BSK, Velmurugan R (2017) Comparative study of impact strength characteristics of treated and untreated sisal polyester composites. Procedia Eng 173:778–785. CrossRefGoogle Scholar
  27. 27.
    Devi LU, Bhagawan SS, Thomas S (1997) Mechanical properties of pineapple leaf fiber-reinforced polyester composites. J Appl Polym Sci 64:1739–1748.;2-T CrossRefGoogle Scholar
  28. 28.
    Senthilkumar K, Saba N, Chandrasekar M et al (2019) Evaluation of mechanical and free vibration properties of the pineapple leaf fibre reinforced polyester composites. Constr Build Mater. Google Scholar
  29. 29.
    Lopattananon N, Panawarangkul K, Sahakaro K, Ellis B (2006) Performance of pineapple leaf fiber-natural rubber composites: the effect of fiber surface treatments. J Appl Polym Sci 102:1974–1984. CrossRefGoogle Scholar
  30. 30.
    Dai D, Fan M (2010) Characteristic and performance of elementary hemp fibre. Mater Sci Appl 1:336Google Scholar
  31. 31.
    Huda MS, Drzal LT, Mohanty AK, Misra M (2008) Effect of chemical modifications of the pineapple leaf fiber surfaces on the interfacial and mechanical properties of laminated biocomposites. Compos Interfaces 15:169–191. CrossRefGoogle Scholar
  32. 32.
    Asim M, Jawaid M, Abdan K, Ishak MR (2016) Effect of alkali and silane treatments on mechanical and fibre-matrix bond strength of kenaf and pineapple leaf fibres. J Bionic Eng 13:426–435. CrossRefGoogle Scholar
  33. 33.
    Abraham E, Deepa B, Pothan LA et al (2011) Extraction of nanocellulose fibrils from lignocellulosic fibres: a novel approach. Carbohydr Polym. Google Scholar
  34. 34.
    Mwaikambo LY, Tucker N, Clark AJ (2007) Mechanical properties of hemp-fibre-reinforced euphorbia composites. Macromol Mater Eng 292:993–1000CrossRefGoogle Scholar
  35. 35.
    Kumar K, Senthil I, Siva P, Jeyaraj JT, Winowlin Jappes SC, Amico and NR (2014) Synergy of fiber length and content on free vibration and damping behavior of natural fiber reinforced polyester composite beams. Mater Des 56:379–386CrossRefGoogle Scholar
  36. 36.
    Rojo E, Alonso MV, Oliet M et al (2015) Effect of fiber loading on the properties of treated cellulose fiber-reinforced phenolic composites. Compos Part B Eng 68:185–192. CrossRefGoogle Scholar
  37. 37.
    Sepe R, Bollino F, Boccarusso L, Caputo F (2018) Influence of chemical treatments on mechanical properties of hemp fiber reinforced composites. Compos Part B Eng 133:210–217. CrossRefGoogle Scholar
  38. 38.
    Asumani OML, Reid RG, Paskaramoorthy R (2012) Author’ s personal copy Composites: Part A The effects of alkali–silane treatment on the tensile and flexural properties of short fibre non-woven kenaf reinforced polypropylene composites. Compos Part A Appl Sci Manuf 43:1431–1440CrossRefGoogle Scholar
  39. 39.
    Herrera-Franco PJ, Valadez-González A (2004) Mechanical properties of continuous natural fibre-reinforced polymer composites. Compos Part A Appl Sci Manuf 35:339–345. CrossRefGoogle Scholar
  40. 40.
    Li X, Tabil LG, Panigrahi S (2007) Chemical treatments of natural fiber for use in natural fiber-reinforced composites: a review. J Polym Environ 15:25–33. CrossRefGoogle Scholar
  41. 41.
    Harish S, Michael DP, Bensely A (2009) Mechanical property evaluation of natural fiber coir composite. Mater Charact 60:44–49. CrossRefGoogle Scholar
  42. 42.
    Mwaikambo LY, Ansell MP (2002) Chemical modification of hemp, sisal, jute, and kapok fibers by alkalization. J Appl Polym Sci 84:2222–2234CrossRefGoogle Scholar
  43. 43.
    Hossain KaH, Khan M, Khan M R a (2009) Mechanical properties of the coir fiber-reinforced polypropylene composites: effect of the incorporation of jute fiber. J Compos Mater 44:401–416. Google Scholar
  44. 44.
    Punyamurthy R, Sampathkumar D, Ranganagowda RPG et al (2017) Mechanical properties of abaca fiber reinforced polypropylene composites: effect of chemical treatment by benzenediazonium chloride. J King Saud Univ Eng Sci 29:289–294. Google Scholar
  45. 45.
    Ozturk S (2010) Effect of fiber loading on the mechanical properties of kenaf and fiberfrax fiber-reinforced phenol-formaldehyde composites. J Compos Mater 44:2265–2288. CrossRefGoogle Scholar
  46. 46.
    Murali Mohan Rao K, Mohana Rao K, Ratna Prasad AV (2010) Fabrication and testing of natural fibre composites: vakka, sisal, bamboo and banana. Mater Des 31:508–513. CrossRefGoogle Scholar
  47. 47.
    Mahato K, Goswami S, Ambarkar A (2014) Morphology and mechanical properties of sisal fibre/vinyl ester composites. Fibers Polym 15:1310–1320CrossRefGoogle Scholar
  48. 48.
    Pappu A, Saxena M, Thakur VK et al (2016) Facile extraction, processing and characterization of biorenewable sisal fibers for multifunctional applications. J Macromol Sci Part A 53:424–432CrossRefGoogle Scholar
  49. 49.
    Sathishkumar T, Navaneethakrishnan P, Shankar S, Kumar J (2012) Mechanical properties of randomly oriented snake grass fiber with banana and coir fiber-reinforced hybrid composites. J Compos Mater. Google Scholar
  50. 50.
    Zhu J, Zhu H, Immonen K et al (2015) Improving mechanical properties of novel flax/tannin composites through different chemical treatments. Ind Crops Prod 67:346–354CrossRefGoogle Scholar
  51. 51.
    Ahmed KS, Vijayarangan S (2008) Tensile, flexural and interlaminar shear properties of woven jute and jute-glass fabric reinforced polyester composites. J Mater Process Technol 207:330–335CrossRefGoogle Scholar
  52. 52.
    Mishra S, Mohanty a K, Drzal LT et al (2003) Studies on mechanical performance of biofibre/glass reinforced polyester hybrid composites. Compos Sci Technol 63:1377–1385. CrossRefGoogle Scholar
  53. 53.
    Goud G, Rao RN (2011) Effect of fibre content and alkali treatment on mechanical properties of Roystonea regia-reinforced epoxy partially biodegradable composites. Bull Mater Sci 34:1575–1581CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Centre for Composite Materials, Department of Mechanical EngineeringKalasalingam Academy of Research and EducationSrivilliputturIndia
  2. 2.Department of Mechanical and Process Engineering, The Sirindhorn International ThaiGerman, Graduate School of Engineering (TGGS)King Mongkut’s University of Technology North BangkokBangkokThailand
  3. 3.Laboratory of Biocomposite Technology, Institute of Tropical Forestry and Forest Products (INTROP)Universiti Putra MalaysiaUPM SerdangMalaysia
  4. 4.Department of Aerospace Engineering, Faculty of EngineeringUniversiti Putra MalaysiaUPM SerdangMalaysia

Personalised recommendations