Malaysian Journal of Analytical Sciences Vol 18 No 2 (2014): 466 - 477

 

 

 

THERMAL PROPERTIES, STRUCTURE AND MORPHOLOGY OF GRAPHENE REINFORCED POLYETHYLENE TEREPHTHALATE/POLYPROPYLENE NANOCOMPOSITES

 

(Sifat Termal, Struktur dan Morfologi Graphene Bertetulang Polietilena Tereftalat /Polipropilena)

 

I. M. Inuwa, A.  Hassan*, S. A. Shamsudin

 

Department of Polymer Engineering,

Faculty of Chemical and Natural Resources Engineering,

Universiti Teknologi Malaysia, UTM 81310, Skudai, Johor Darul Takzim, Malaysia

 

*Corresponding author: azmanh@cheme.utm.my

 

 

Abstract

In this work the thermal properties, structure and morphology of a blend of polyethylene terephthalate (PET) and polypropylene (PP) reinforced with graphene nanoplatelets (GNP) were investigated. A blend of PET/PP (70/30 weight percent) compatibilized with styrene-ethylene-butylene-styrene grafted maleic anhydride triblock copolymer (10 phr) were fabricated by melt extrusion process in a twin screw extruder. The effective thermal conductivity of the nanocomposites increased as a function of the GNP concentration. More than 80% increase in effective thermal conductivity was observed for the 7 phr reinforced sample compared to the neat blend. This observation was attributed to the development interconnected GNP sheets which formed heat conductive bridges that are suitable for maximum heat transfer. However, in the case of thermal stability which is a function of dispersibility of GNP in polymer matrix, the maximum increase was observed at 3 phr GNP loading which could be attributed to the uniform dispersion of GNPs in the matrix... It is explained that the GNP nanofillers migrated to the surface of matrix forming an effective oxygen barrier due to char formation. Morphological studies revealed uniform dispersion graphene in the polymer matrix at 3 phr GNP loading along with isolated instances of exfoliation of the graphene layers.

 

Keywords: Thermal conductivity, thermal stability, polyethylene terephthalate, polypropylene, graphene nanoplatelets

 

Abstrak

Dalam kajian ini, sifat haba, struktur dan morfologi adunan polietilena tereftalat (PET) dan polipropilena (PP)  diperkukuhkan dengan nanoplatlet grafit berkelupasan (GNP) telah dikaji.  Adunan PET / PP (70/30 peratus berat) diserasikan dengan kopolimer triblok maleat anhidrida tercangkuk stirena-etilena-butilena-stirena (10 phr) telah dipalsukan oleh proses penyemperitan mencairkan dalam ekstruder skru berkembar. Keberaliran haba berkesan daripada nanokomposit meningkat sebagai fungsi kepekatan GNP. Peningkatan lebih daripada 80% dalam kekonduksian terma berkesan diperhatikan untuk sampel diperkukuhkan 7 phr berbanding dengan gabungan kemas. Pemerhatian ini disebabkan oleh pembangunan saling kunci GNP yang membentuk jambatan haba konduktif yang sesuai untuk pemindahan haba maksimum. Walau bagaimanapun, dalam kes kestabilan terma yang merupakan fungsi penyerakan GNP dalam matriks polimer, peningkatan maksimum diperhatikan pada kandungan 3 phr GNP  yang boleh dikaitkan dengan penyebaran seragam GNPs dalam matriks.  Ia menjelaskan bahawa yang pengisi nano GNP berhijrah ke permukaan matriks membentuk halangan oksigen yang berkesan kerana pembentukan char. Kajian morfologi mendedahkan penyebaran seragam graphene dalam matriks polimer pada kandungan 3 phr GNP  bersama-sama dengan kes terpencil pengelupasan lapisan graphene.

 

Kata kunci: kekonduksian terma, kestabilan terma, polietilena tereftalat, polipropilena, nanoplatlet graphene

 

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