Sains Malaysiana 42(4)(2013): 429–434

Flame Retardancy and Mechanical Properties of Kenaf Filled Polypropylene (PP) Containing Ammonium Polyphosphate (APP)

(Kerencatan Nyalaan dan Sifat Mekanikal Kenaf Berpengisi Polipropilena yang Mengandungi Ammonia Polifosfat (APP))

Atikah Ismail, Azman Hassan* & Aznizam Abu Bakar

Enhanced Polymer Research group (EnPRO), Department of Polymer Engineering

Faculty of Chemical Engineering, Universiti Teknologi Malaysia

81310 Skudai, Johor Darul Takzim, Malaysia

M. Jawaid

Department of Biocomposite Technology, Institute of Tropical Forestry and Forest Products, Universiti Putra Malaysia, 43400 Serddang, Selangor, Malaysia

Diserahkan: 3 Jun 2011 / Diterima: 20 Januari 2012

ABSTRACT

The effects of ammonium polyphosphate (APP) as flame retardant and kenaf as fillers on flammability, thermal and mechanical properties of polypropylene (PP) composites were determined. Test specimens were prepared by using a co-rotating twin screw extruder for the compounding process followed by injection molding. The flame retardancy of the composites was determined by using limiting oxygen index (LOI) test. Addition of flame retardant into kenaf-PP composites significantly increased the LOI values that indicated the improvement of flame retardancy. Thermogravimetric analysis was done to examine the thermal stability of the composites. The addition of kenaf fiber in PP composites decreased the thermal stability significantly but the influence of APP on thermal properties of the kenaf-filled PP composites was not significant. The flexural strength and modulus of composites increased with the addition of APP into kenaf filled PP composite. The addition of APP into kenaf filled PP causes increase in the impact strength while increasing the APP content in the kenaf filled PP composite show decrease in impact strength.

Keywords: Flame retardancy; mechanical properties; natural fiber polymer composites

ABSTRAK

Kesan ammonia polifosfat (APP) sebagai rencatan nyalaan dan kenaf sebagai pengisi ke atas sifat-sifat kebolehupayaan nyalaan, terma dan mekanikal bagi komposit polipropilena (PP) telah dikaji. Spesimen ujian telah disediakan dengan menggunakan alat penyemprit skru berkembar untuk proses penyebatian dan diikuti dengan alat acuan suntikan. Kerencatan nyalaan bagi komposit juga telah ditentukan dengan menggunakan alat ujian pengehad indeks oksigen (LOI). Penambahan perencat kebakaran ke dalam komposit kenaf-PP meningkatkan nilai LOI yang menunjukkan kemajuan dalam keupayaan rencatan nyalaan. Analisis termogravimetri dilakukan untuk memeriksa kestabilan terma bagi komposit. Penambahan serat kenaf ke dalam komposit PP menurunkan kestabilan terma secara ketara tetapi sebaliknya, kesan APP ke atas sifat-sifat terma bagi kenaf berpengisi komposit PP tidak mempunyai perubahan yang ketara. Kekuatan dan modulus lenturan bagi komposit meningkat dengan penambahan APP ke dalam kenaf yang berpengisi komposit PP. Penambahan APP ke dalam kenaf berpengisi PP juga menyebabkan peningkatan dalam kekuatan hentaman manakala peningkatan kandungan APP di dalam kenaf berpengisi komposit PP menunjukkan penurunan di dalam kekuatan hentaman.

Kata kunci: Rencatan nyalaan; serat semula jadi komposit polimer; sifat-sifat mekanikal

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*Pengarang untuk surat-menyurat; email: azmanh@cheme.utm.my