Malaysian Journal of Analytical Sciences Vol 20 No 5 (2016): 1145 - 1152

DOI: http://dx.doi.org/10.17576/mjas-2016-2005-21

 

 

 

NEW PROCESS DEPROTENISED NATURAL RUBBER (PUREPRENAÔ): RAW RUBBER, PROCESSABILITY AND BASIC PHYSICAL PROPERTIES

 

(Proses Baru Getah Asli Nyah Protein (Pureprena™): Getah Mentah, Kebolehprosesan dan

Sifat Fizikal)

 

Rohaidah Abd Rahim*, Teku Zakwan Zaeimoedin, Ahmad Khairul Muhamad and Siti Salina Sarkawi

 

Engineering & Technology Division,

Malaysian Rubber Board,

 RRIM Research Station Sg. Buloh, 47000 Sungai Buloh, Selangor, Malaysia

 

*Corresponding author: rohaidah@lgm.gov.my

 

 

Received: 10 June 2015; Accepted: 21 July 2016

 

 

Abstract

Malaysian Rubber Board has developed a new process deprotenised natural rubber (Pureprena™) by treating fresh natural latex with an industrial enzyme which hydrolyses all naturally-occuring proteins in the latex into water-soluble forms.  Further research is carried out to determine the processability performance of Pureprena™ by Mooney viscometer, rubber process analyser and capillary rheometer. The Pureprena™ in bale form has low nitrogen, low ash and volatile matter contents as well as being lighter in color compared to commercial Standard Malaysian Rubber. The rheological results indicate that the Pureprena™ has a comparable rheological behavior with synthetic polyisoprene at low shear rate as determined by RPA and capillary rheometer curves. The measurement by viscometer confirms the rheological behavior at low shear rate. However, Pureprena™ has a faster mill breakdown rate compared to synthetic polyisoprene and SMR at 60 °C. All rubbers were compounded using the soluble efficient vulcanisation system especially for manufacturing engineering rubber products. It was found that Pureprena™ vulcanisate has comparable tensile strength, modulus, resilience and volume swelling in water compared to synthetic polyisoprene vulcanisate.

 

Keywords:    deprotenised natural rubber, soluble efficient vulcanisation cure system, tangent delta, capillary rheometer, rubber process analyser

 

Abstrak

Lembaga Getah Malaysia telah membangunkan proses baru getah asli nyah protein (Pureprena™) dengan merawat getah asli segar menggunakan enzim perindustrian yang akan menghidrolisis semua protein semulajadi di dalam susu getah kepada bentuk larut-air. Penyelidikan lanjut dijalankan bagi menentukan prestasi kebolehprosesan Pureprena™ menggunakan viskometer Mooney, penganalisa proses getah dan reometer kapilari. Bandela Pureprena™ mempunyai kandungan nitrogen yang rendah, kandungan abu yang rendah dan kandungan jirim meruap serta warna yang lebih cerah berbanding getah komersial Getah Standard Malaysia. Keputusan reologi menunjukkan bahawa Pureprena™ mempunyai kelakuan reologi setanding dengan poliisoprena pada kadar ricih yang rendah dari ujian RPA dan keluk kapilari reometer. Pengukuran dari viskometer mengesahkan kelakuan reologi pada kadar ricih yang rendah ini. Walau bagaimanapun, Pureprena™ mempunyai kadar pecahan yang lebih pantas berbanding sintetik poliisoprena dan SMR pada suhu 60 °C. Penyebatian getah adalah menggunakan sistem pemvulkanan cekap larut khas bagi produk-produk getah kejuruteraan. Ia didapati bahawa Pureprena™ vulkanisat mempunyai kekuatan tensil, modulus, daya tahan dan pembengkakan dalam air yang setanding dengan vulkanisat sintetik poliisoprena.

 

Kata kunci:    getah asli nyah protein, sistem pemvulkanan larut EV, tangen delta, reometer kapilari, penganalisis proses getah

 

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