Malaysian Journal of Analytical Sciences Vol 22 No 6 (2018): 1014 - 1022

DOI: 10.17576/mjas-2018-2206-11

 

 

 

EFFECT OF EPOXIDISED NATURAL RUBBERS ON CALCIUM CARBONATE-FILLED NATURAL RUBBER COMPOUNDS

 

(Kesan Getah Asli Terepoksida Terhadap Sebatian Getah Asli Terisi Kalsium Karbonat)

 

Indra Surya¹*, Seri Maulina¹, Hanafi Ismail²

 

¹Department of Chemical Engineering,

Universitas Sumatera Utara, Medan, 20155, Indonesia

²School of Materials and Mineral Resources Engineering,

Universiti Sains Malaysia, Engineering Campus, Nibong Tebal, 14300, Penang, Malaysia

 

*Corresponding author:  indradanas@yahoo.com

 

 

Received: 27 July 2017; Accepted: 28 April 2018

 

 

Abstract

By using a semi-efficient vulcanisation system, two grades of epoxidised natural rubbers (ENR 25 and ENR 50) were incorporated separately into calcium carbonate (CaCO₃) filled natural rubber (NR) compounds at 5.0, 10.0, 15.0, 20.0 and 25.0 phr. An investigation was carried out to examine the effects of the ENRs on cure characteristics, rubber - filler interaction and crosslink density of the CaCO₃ filled NR compounds. Results revealed that both ENR 25 and ENR 50 functioned as curatives and compatibilizers. They decreased the scorch time, cure time and minimum torque; increased torque difference, crosslink density and degree of rubber - filler interaction. The higher the ENRs loadings; the lower were the scorch and cure times and the higher were the torque difference, crosslink density and degree of rubber - filler interaction. At a similar loading, ENR 50 exhibited a more pronounced curative and compatibilization effects than ENR 25.

 

Keywords:  epoxidised natural rubber, calcium carbonate, cure characteristics, natural rubber, rubber - filler interaction

 

Abstrak

Dua gred getah asli terepoksida (ENR 25 dan ENR 50) dimasukkan secara berasingan ke dalam sebatian getah asli terisi kalsium karbonat pada 5.0, 10.0, 15.0, 20.0 dan 25.0 phr dengan menggunakan kaedah pemvulkanan separa cekap (semi-EV). Kajian terhadap sebatian untuk mengkaji kesan ENR terhadap ciri-ciri pematangan, interaksi getah-pengisi dan ketumpatan sambung-silang telah dijalankan. Hasil kajian menunjukkan kedua-dua gred ENR berfungsi sebagai kuratif dan pengserasi. ENR 25 dan ENR 50 memberikan kesan penurunan terhadap masa pembakaran, masa pematangan dan tork minima; peningkatan perbezaan tork, ketumpatan sambung-silang dan darjah interaksi pengisi-getah. Semakin meningkat jumlah kedua-dua ENR, semakin rendah nilai masa pembakaran dan pematangan dan semakin tinggi nilai perbezaan tork, ketumpatan sambung-silang dan darjah interaksi pengisi-getah. Pada nilai muatan yang sama, ENR 50 menunjukkan kesan yang lebih baik sebagai kuratif dan pengserasi berbanding ENR 25.

 

Kata kunci:  getah asli terepoksida, kalsium karbonat, ciri-ciri pematangan, getah asli, interaksi getah-pengisi

 

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