Sains Malaysiana 40(7)(2011): 749–756

Effect of Rice Husk Surface Modification by LENR the on Mechanical Properties of NR/HDPE Reinforced Rice Husk Composite

(Kesan Rawatan Permukaan Sekam Padi dengan LENR ke Atas Sifat Mekanik

Komposit NR/HDPE diperkuat Sekam Padi)

Rahmadini Syafri, Ishak Ahmad & Ibrahim Abdullah*

Pusat Pengajian Sains Kimia dan Teknologi Makanan, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

Received: 23 October 2009 / Accepted: 20 August 2010

ABSTRACT

Surface modification of rice husk (RH) with alkali pre-treatment (NaOH solution 5% w/v) was carried out at the initial state to investigate the effect of surface treatment of fibre on the surface interaction between fibre and rubber. Further modification of RH surfaces after alkali treatment was using Liquid Epoxidized Natural Rubber (LENR) coating at three concentrations, 5%, 10%, and 20% wt LENR solution in toluene. Interfacial morphology and chemical reactions between RH fibre and rubber were analyzed by FTIR and Scanning Electron Microscope (SEM). It was found that 10% wt LENR solution gave the optimum interaction between fibre and rubber. Matrix and composite blends derived from 60% natural rubber (NR), 40% high density polyethylene (HDPE) reinforced with RH fibre were prepared using an internal mixer (Brabender Plasticoder). Result showed that pre-treatment of RH treated with 5% NaOH followed by treatment with 10% LENR solution given the maximum interaction between fibre and matrix that gave rise to better mechanical properties of the composites.

Keywords: High density polyethylene; liquid epoxidized natural rubber; mechanical properties; rice husks; sodium hydroxide

ABSTRAK

Modifikasi permukaan sekam padi (SP) dengan pra-rawatan alkali (larutan NaOH 5% w/v) telah dijalankan untuk mengkaji keberkesanan rawatan permukaan SP ke atas interaksi permukaan antara serabut dan getah. Modifikasi permukaan SP seterusnya adalah dengan penyalutan getah asli terepoksida cecair (LENR) pada tiga kepekatan yang berbeza iaitu 5%, 10% dan 20% w/w LENR dalam larutan toluena. Morfologi antaramuka dan reaksi kimia antara SP dan getah (LENR) dikaji melalui analisis FTIR dan mikroskop elektron imbasan (SEM). Didapati bahawa larutan LENR 10% memberikan interaksi yang optimum antara serabut dan getah (LENR). Adunan matriks dan komposit disediakan daripada 60% getah asli (NR), 40% polietilena berketumpatan tinggi (HDPE) diperkuat dengan pengisi SP di jalankan dengan menggunakan pengadun dalaman (Brabender Plasticoder). Keputusan kajian menunjukkan bahawa pra-rawatan SP dengan larutan NaOH 5% diikuti dengan rawatan LENR 10% memberikan interaksi maksimum antara pengisi dan matriks seterusnya meningkatkan sifat mekanik kommposit

Kata kunci: Getah asli terepoksida cecair; natrium hidroksida (NaOH); polietilena berketumpatan tinggi; sekam padi; sifat mekanik

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*Corresponding author; email: dia@ukm.my