Sains Malaysiana 44(11)(2015): 1615–1623

 

Mechanical, Thermal and Chemical Resistance of Epoxidized Natural Rubber Toughened Polylactic Acid Blends

(Rintangan Mekanikal, Termal dan Kimia Adunan Asid Polilaktik Diperkukuhkan dengan Getah Asli Terepoksida)

 

MAT UZIR WAHIT1*, AZMAN HASSAN2, AKOS NOEL IBRAHIM2, NURHAYATI AHMAD ZAWAWI2 & KAYATHRE KUNASEGERAN2

 

1Center for Composites (CfC), Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim

Malaysia

 

2Enhanced Polymer Research Group (EnPRO), Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim

Malaysia

 

Received: 28 March 2015 /Accepted: 12 June 2015

 

ABSTRACT

Polylactic acid (PLA)/Epoxidized natural rubber (ENR-50) blends were prepared by melt extrusion followed by injection molding to fabricate the test samples. The effect of ENR-50 loadings on the morphological, mechanical, chemical resistance and water absorption properties of the blends were studied using standard methods. The toughness of the blend improved with ENR loading up to 20 wt. % but flexural and tensile strength decreased. The balanced mechanical properties were obtained at 20 wt. % ENR-50 loading. SEM showed good distribution and increased ENR particle size as ENR content increased from 10 to 30 wt. %. The differential scanning calorimeter (DSC) showed a steady drop in crystallization temperature (Tc) as ENR content increases while the glass transition temperature (Tg) remained unchanged. Water absorption was observed to increase with ENR loadings. Increase in ENR content was also observed to reduce the chemical resistance of the blends.

 

Keywords: Blend; epoxidized natural rubber; extrusion; mechanical properties; polylactic acids

 

ABSTRAK

Adunan asid polilaktik (PLA)/getah asli terepoksida (ENR 50) disediakan dengan menggunakan kaedah penyemperitan leburan dan diikuti dengan kaedah pengacuan suntikan untuk menghasilkan sampel untuk pengujian. Kesan kandungan ENR 50 terhadap ciri morfologi, mekanik, rintangan kimia dan penyerapan air dikaji dengan menggunakan kaedah piawai. Kadar keliatan adunan tersebut meningkat dengan peningkatan kandungan ENR sehingga 20% tetapi kadar kelenturan dan tegangan menurun. Ciri mekanik yang seimbang diperoleh dengan 20% kandungan ENR 50. Imej SEM menunjukkan penyerakan ENR 50 yang baik dan peningkatan saiz partikel selari dengan peningkatan ENR daripada 10% ke 30%. Kalorimeter imbasan pembezaan (DSC) menunjukkan penurunan suhu penghabluran kristal yang stabil dengan peningkatan kandungan ENR 50, manakala suhu peralihan kaca kekal tidak berubah. Kadar penyerapan air didapati meningkat dengan peningkatan kandungan ENR 50. Peningkatan kandungan ENR juga dilihat dapat mengurangkan rintangan kimia adunan tersebut.

 

Kata kunci: Adunan; asid polilaktik; getah asli terepoksida; penyemperitan; sifat mekanik

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*Corresponding author; email: mat.uzir@cheme.utm.my

 

 

 

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