Sains Malaysiana 42(6)(2013): 811–818

Fire-retardant Polyester Composites from Recycled Polyethylene Terephthalate (PET)

Wastes Reinforced with Coconut Fibre

(Komposit Poliester Perencat Api Berasaskan Bahan Buangan PET Kitar Semula Diperkuat Serabut Kelapa)

Nurul Munirah Abdullah & IshakAhmad*

School of Chemical Sciences and Food Technology, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

Received: 28 May 2012/Accepted: 2 October 2012

ABSTRACT

Coconut fibre reinforced composite was prepared by blending unsaturated polyester resin (UPR) from waste PET with 0.3 v% of coconut fibre. The coconut fibres were pre-treated with sodium hydroxide followed by silane prior to inclusion into the UPR. The untreated coconut fibres reinforced composite were used as a control. Dricon® as a phosphate type of flame retardant was then added to the composite to reduce the flammability of the composite. The amount of Dricon® was varied from 0 to 10 wt% of the overall mass of resin. The burning properties and limiting oxygen index (LOI) of the treated and untreated composites increased with the addition of Dricon®. The tensile strength and modulus of both composites were also increased with the addition of Dricon®. The treated fibre composite with 5 wt% Dricon® showed the highest burning time and LOI with the values of 101.5 s and 34 s, respectively. The optimum tensile strength and modulus for treated fibre composite was at 5 wt% Dricon® whereas the untreated fibre composite was at 2.5 wt% loading of Dricon®. Thermogravimetry (TGA) analysis indicated that the degradation temperature increased with the addition of Dricon® up to 5 wt% into UPR/coconut fibre composites. Morphological observations indicated better distribution of Dricon® for treated fibre composite resulted in enhancement of the tensile properties of the treated fibre composite.

Keywords: Coconut fiber; flame retardant; polyester; polyethylene terephthalate

ABSTRAK

Komposit diperkuat serabut kelapa disediakan dengan mengadunkan resin poliester tak tepu (UPR) daripada bahan buangan PET pada komposisi 0.3% isi padu serabut kelapa. Pra-rawatan serabut kelapa telah dilakukan menggunakan natrium hidroksida diikuti oleh silana sebelum dicampurkan ke dalam UPR. Komposit diperkuat serabut kelapa tanpa rawatan telah digunakan sebagai kawalan. Dricon® iaitu sejenis perencat api fosfat kemudiannya ditambah kepada komposit untuk mengurangkan kebolehbakaran komposit. Komposisi Dricon® telah divariasi antara 0-10% berat jisim keseluruhan resin. Sifat pembakaran dan indeks pengehadan oksigen (LOI) bagi komposit terawat dan tanpa rawatan didapati telah meningkat dengan penambahan Dricon®. Kekuatan regangan dan modulus kedua-dua komposit juga telah meningkat dengan penambahan Dricon®. Komposit yang diperkuat serabut terawat dengan 5% berat Dricon® menunjukkan masa pembakaran dan LOI yang tertinggi dengan nilai 101.5 s dan 34 s masing-masing. Kekuatan regangan dan modulus yang optimum bagi komposit dengan serabut terawat adalah pada 5% berat Dricon® manakala komposit dengan serabut tidak terawat adalah pada 2.5% berat Dricon®. Analisis termogravimetri (TGA) menunjukkan bahawa suhu degradasi meningkat dengan penambahan Dricon® sehingga 5% berat yang ditambah ke dalam komposit UPR/serabut kelapa. Pemerhatian morfologi menunjukkan penyebaran Dricon® yang lebih baik bagi komposit dengan serabut yang dirawat menyebabkan peningkatan sifat regangan komposit.

Kata kunci: Kerintangan api; poliester; polietilena tereftalat; serabut kelapa

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*Corresponding author; email: gading@ukm.my