Sains Malaysiana 43(8)(2014): 1231-1237

Penyediaan dan Pencirian Nanokomposit Epoksi Berpenguat Getah Asli Terepoksida

(Preparation and Characterisation of Epoxidized Natural Rubber Reinforced Epoxy Nanocomposites)

Se Yong Eh Noum*, Sahrim Ahmad, Rozaidi Rasid, Yew Chin Hock,

Lee Yip Seng & Mou'ad A. Tarawneh

School of Applied Physic, Faculty of Science and Technology, Universiti Kebangsaan Malaysia

43600 Bangi, Selangor, Malaysia

Received: 19 December 2011/Accepted: 4 October 2013

ABSTRAK

Komposit epoksi berpengisi hibrid OMMT (organo-monmorilonit) dan getah asli terepoksida (ENR) telah dihasilkan dengan menggunakan kaedah penyemperitan berskru kembar pusingan searah. Ujian regangan ke atas sistem epoksi yang dihasilkan menunjukkan modulus Young bagi komposit hibrid epoksi adalah lebih tinggi daripada resin tanpa pengisi dan nilai modulus didapati meningkat dengan peningkatan komposisi OMMT dalam matriks (setinggi 40% peningkatan). Hal ini dipercayai adalah disebabkan oleh sifat tegar lapisan MMT. Sementara itu, peningkatan luas permukaan kawasan antara fasa ekoran kehadiran fasa penambah didapati telah mengurangkan tegasan alah dan terikan akhir komposit hibrid yang dihasilkan. Pemeriksaan mikrostruktur komposit hibrid epoksi melalui TEM dan XRD mendedahkan taburan OMMT dalam matriks epoksi dengan susunan interkalasi dan pengelupasan. Analisis DSC ke atas sampel yang termatang menunjukkan bahawa T_g­ sistem komposit hibrid adalah rendah berbanding dengan sistem perduaan (E5B dan E5LE). Pengurangan ketumpatan taut silang disyaki merupakan punca penyusutan T_g ini.

Kata kunci: Getah asli terepoksida; komposit epoksi; organo-monmorilonit; penyemperitan berskru kembar

ABSTRACT

OMMT (organo-montmorillonite) and epoxidized natural rubber (ENR) filled epoxy hybrid composites were produced via co-rotating twin-screw extrusion technique. Tensile test on the epoxy composites systems shows that the Young's modulus of the epoxy hybrid composites were higher than the Young's modulus of unfilled epoxy and the value of the modulus were found to be increasing with the increase of OMMT composition in the matrix (exceeding 40% increment). This finding is believed to be attributed to the stiff characteristic of MMT. Meanwhile, the presence of fillers resulted in the decrement of yeild stress and strain at break of the hybrid composites. Microstructure examination on the hybrid composites via TEM and XRD techniques showed that the distribution of OMMT in the matrix consist of intercalation and exfoliation. DSC analysis on the cured sample showed that the T_g of the hybrid system is lower than the binary system (E5B and E5LE). It was suggested that the decrement of the cross link density is the reason for the decline in T_g.

Keywords: Epoxidized natural rubber; epoxy composites; organo-monmorillonite; twin screw extruder

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*Corresponding author; email: seyong01my@yahoo.co.uk