Sains Malaysiana 52(5)(2023): 1435-1451


Effect of Alkali Treatment and Fibre Composition on the Performance of Pineapple Leaf Fibre-Polyvinyl Alcohol Composites

(Kesan Rawatan Alkali dan Komposisi Serat terhadap Prestasi Komposit Alkohol Serat-Polivinil Daun Nanas)




1Department of Chemistry, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Federal Territory, Malaysia

2Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Federal Territory, Malaysia


Diserahkan: 18 Oktober 2022/Diterima: 7 April 2023



This paper studied the properties of composites based on polyvinyl alcohol reinforced with pineapple leaf fibres (PALF/PVA). The surface of pineapple leaf fibres (PALF) has been previously treated with 6% sodium hydroxide solution. The influence of fibre loading and fibre surface treatment were examined. Analysis by Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) displayed physico-chemical changes on treated PALF/PVA composites compared to untreated PALF/PVA composites. The results from thermogravimetric analysis (TGA) showed that the introduction of untreated PALF into the composites enhanced the thermal stability of the composites. Progressive improvement of thermal stability was discovered by associating treated PALF with the composites. The treated PALF composites produced also improved mechanical properties with increasing fibre content. Differential scanning calorimetric (DSC) analyses showed no significant changes in melting temperatures upon incorporating untreated PALF into the PALF/PVA composites. The best improvement in tensile strength value was obtained for treated PALF composite having 3 wt% of fibre loading, with enhancements of about 11% and 54%, compared to untreated PALF composites and plain PVA matrix, respectively.


Keywords: Alkali treatment; interfacial adhesion; MD2-pineapple leaf fibres; polymer composites; polyvinyl alcohol



Kertas ini mengkaji sifat komposit berdasarkan polivinil alkohol yang diperkuat dengan serat daun nanas (PALF/PVA). Permukaan serat daun nanas (PALF) sebelum ini telah dirawat dengan larutan natrium hidroksida 6%. Pengaruh komposisi serat dan rawatan permukaan serat telah dikaji. Analisis oleh Fourier-transformasi infra merah (FTIR) dan pembelauan sinar-X (XRD) memaparkan perubahan fiziko-kimia pada komposit PALF/PVA yang dirawat berbanding komposit PALF/PVA yang tidak dirawat. Keputusan daripada analisis termogravimetri (TGA) menunjukkan bahawa kehadiran PALF yang tidak dirawat ke dalam komposit meningkatkan kestabilan terma komposit. Peningkatan progresif kestabilan terma ditemui dengan kehadiran PALF yang dirawat di dalam komposit. Peningkatan kandungan serat yang dirawat di dalam komposit juga didapati menyebabkan peningkatan dalam sifat mekanikal. Analisis kalorimetrik pengimbasan pembezaan (DSC) menunjukkan tiada perubahan ketara dalam suhu lebur apabila PALF yang tidak dirawat digabungkan ke dalam komposit PALF/PVA. Penambahbaikan paling terbaik dalam nilai kekuatan tegangan diperoleh oleh komposit dengan PALF yang dirawat pada kandungan serat 3 wt% dengan peningkatan sebanyak 11% dan 54%, berbanding komposit PALF yang tidak dirawat dan matriks PVA.


Kata kunci: Komposit polimer; lekatan antara muka; polivinil alkohol; rawatan alkali; serat daun nanas MD-2



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