Sains Malaysiana 40(7)(2011): 719–724

Influence of Compounding Methods on Poly(vinyl) Alcohol/Sago Pith Waste Biocomposites: Mechanical and Water Absorption Properties

(Kesan Kaedah Pencampuran ke atas Biokomposit Polivinil Alkohol/Bahan

Buangan Empulur Sagu: Sifat-sifat Mekanik dan Penyerapan Air)

W.Y. Toh*, J.C. Lai & W.A.R. Wan Aizan

Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia

81310 UTM Skudai, Johor, Malaysia

Received: 23 October 2009 / Accepted: 4 August 2010

ABSTRACT

Several methods of incorporating sago pith waste (SPW) into poly(vinyl alcohol) (PVA) had been conducted: (i) dry blending (PVA/SPW/G), (ii) blending of SPW and pre-plasticized PVA (pPVA/SPW/G) and (iii) blending of pre-plasticized of both PVA and SPW (pPVA/pSPW). The effect of the compounding method on the mechanical and water absorption properties were investigated. The addition of SPW into PVA greatly reduced the tensile strength and elongation at break. The tensile strength and elongation at break of PVA/SPW composites with identical geometry during compounding stage (powder/powder and pellet/pellet), which were PVA/SPW/G and pPVA/pSPW yielded the highest value. The percentage of water absorbed by PVA/SPW/G (without pre-plasticization) was the highest, followed by pPVA/pSPW and pPVA/SPW/G.

Keywords: Mechanical properties; polyvinyl alcohol; sago pith waste; water absorption

ABSTRAK

Beberapa cara untuk mengadunkan bahan buangan empulur sagu (SPW) ke polivinil alkohol (PVA) telah dilakukan: i) pengadunan secara kering (PVA/SPW/G), (ii) pengadunan SPW dan pra-pemplastikan PVA (pPVA/SPW/G) dan (iii) pengadunan pra-pemplastikan SPW dan pra-pemplastikan PVA (pSPW/pPVA). Kesan kaedah pengadunan ke atas sifat-sifat mekanik dan penyerapan air telah dikaji. Penambahan SPW ke dalam PVA banyak mengurangkan tegasan tegangan dan terikan pada patah. Tegasan tegangan dan terikan pada patah bagi komposit PVA/SPW dengan geometri yang serupa (tepung/tepung dan resin/resin) semasa peringkat pengadunan, iaitu PVA/SPW/G dan pPVA/pSPW menghasilkan nilai tertinggi. Peratus air diserap oleh PVA/SPW/G (tanpa pra-pemplastikan) adalah tertinggi, ini diikuti oleh pPVA/pSPW dan pPVA/SPW/G.

Kata kunci: Alkohol polivinil; bahan buangan empulur sagu; penyerapan air; sifat mekanik

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*Corresponding author; email: tohwenyee@yahoo.co.uk