Malaysian Journal of Analytical Sciences Vol 19 No 6 (2015): 1309 - 1317

 

 

 

DETERMINATION OF CROSSLINK CONCENTRATION BY MOONEY-RIVLIN EQUATION FOR VULCANIZED NR/SBR BLEND AND ITS INFLUENCE ON MECHANICAL PROPERTIES

 

(Menentukan Kepekatan Hubung Silang Menggunakan Persamaan Mooney-Rivlin untuk Campuran Getah Tervulkan NR/SBR dan Pengaruhnya Terhadap Sifat Mekanikal)

 

Azreen Izzati Dzulkifli^*, Che Mohd Som Said, Chan Chin Han

 

Faculty of Applied Sciences,

 Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia

 

*Corresponding author: izzati_dzulana@yahoo.com

 

 

Received: 23 November 2014; Accepted: 3 September 2015

 

 

Abstract

Crosslink concentration is an important property affecting the major characteristic of cured rubber. The crosslink concentration was determined using Mooney-Rivlin equation due to its simple and reliable method. Cured natural rubber and styrene butadiene rubber blend (NR/SBR) with different crosslink concentrations were obtained with different blend ratios of 100/0, 80/20, 70/30, 60/40, 50/50, 40/60 and 0/100. The crosslink concentrations were determined using Mooney-Rivlin Equation and its influence on International Rubber Hardness Tester (IRHD), tensile strength and rebound resilience of NR/SBR blend vulcanizates was investigated. The results showed different blend ratios had an influence on the crosslink concentration of the NR/SBR blend vulcanizates. Obtained data showed that high NR content in NR/SBR blend increased the crosslink concentration. The highest crosslink concentration recorded was for 100/0 blend ratio which was 0.0498 mol kg^-1 RH while the lowest was 0.0295 mol kg^-1 RH for 0/100 blend ratio. The study on the influence of crosslink concentration on IRHD, tensile strength and rebound resilience of NR/SBR blend vulcanizates showed that the mechanical properties increased linearly with the crosslink concentration. High NR content in NR/SBR blends resulted in higher crosslink concentration which improved the performance of mechanical properties for NR/SBR blend.

 

Keywords: crosslink concentration, Mooney-Rivlin equation, natural rubber, styrene butadiene rubber

 

Abstrak

Kepekatan hubung silang adalah perkara penting yang mempengaruhi ciri-ciri utama getah tervulkan. Kepekatan hubung silang telah ditentukan dengan menggunakan persamaan Mooney-Rivlin kerana ia merupakan kaedah yang mudah dan telah diperakui. Campuran getah asli dan stirena butadiena (NR/SBR) dengan kepekatan hubung silang yang berbeza telah diperolehi oleh penggunaan nisbah campuran yang berbeza iaitu 100/0, 80/20, 70/30, 60/40, 50/50, 40/60 dan 0 / 100. Kepekatan hubung silang telah ditentukan menggunakan persamaan Mooney-Rivlin dan pengaruhnya ke atas Ujian Kekerasan Getah Antarabangsa (IRHD), kekuatan tegangan dan pemulihan daya tahan campuran getah NR/SBR telah dikaji. Hasil kajian menunjukkan nisbah campuran yang berbeza mempengaruhi kepekatan hubung silang getah tervulkan NR/SBR. Data yang diperolehi menunjukkan bahawa kandungan getah asli (NR) yang tinggi dalam campuran NR / SBR memberikan peningkatan terhadap kepekatan hubung silang. Kepekatan hubung silang tertinggi dicatatkan adalah untuk nisbah campuran 100/0 iaitu 0.0498 mol kg^-1 RH, manakala yang terendah adalah 0.0295 mol kg^-1 RH untuk nisbah campuran  0/100. Kajian ke atas pengaruh kepekatan hubung silang terhadap ujian IRHD, kekuatan tegangan dan pemulihan daya tahan  campuran getah masak NR/SBR menunjukkan bahawa sifat-sifat mekanikal meningkat secara selari dengan kepekatan hubung silang. Kandungan getah asli (NR) yang tinggi dalam campuran getah NR/SBR menyebabkan kepekatan hubung silang yang lebih tinggi dan sekaligus meningkatkan prestasi sifat mekanik campuran getah NR/SBR.

 

Kata kunci: kepekatan hubung silang, persamaan Mooney Rivlin, getah asli, getah stirena butadiena

 

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